The team examined four desert-dwelling reptiles that occupy different ecological niches and differ in how deeply and reliably they brumate: the Egyptian spiny-tailed lizard Uromastyx aegyptia, the desert monitor Varanus griseus, Savigny’s agama Trapelus savignii, and the ringed wall gecko Tarentola annularis. For each species, kidney tissue was collected during the active season and again during brumation, allowing direct within-species comparison. This design matters because brumation is not a uniform state across reptiles. Some species are obligate brumators that reliably spend the entire cold season dormant, while others are more facultative, emerging during warm spells and adjusting their dormancy to prevailing conditions. The researchers hypothesized that this behavioral difference might be mirrored in the intensity of the physiological responses they measured.

Under the microscope, the brumating kidneys showed clear signs of degeneration. The authors report glomerulosclerosis, a scarring and hardening of the glomeruli, the tufts of capillaries where blood filtration begins, along with necrotic renal tubules and cytoplasmic vacuolization, in which the cells lining the tubules accumulate fluid-filled spaces. These changes echo earlier observations in hibernating mammals, where renal tissue undergoes structural remodeling during cold ischemia and then recovers on arousal. In mammals such as ground squirrels and bears, the kidney has become a natural model of organ preservation, because it tolerates months of reduced blood flow and low temperature without permanent injury. The Egyptian lizards appear to be running a comparable program, with structural changes that look damaging in a snapshot but are presumably reversible when the animals rewarm in spring.

Morphometric analysis, in which structures are measured and compared statistically, revealed that the direction of renal change was not uniform across species. Glomerular diameter decreased significantly during brumation in Uromastyx aegyptia and Tarentola annularis, but increased in Varanus griseus and Trapelus savignii. The proximal tubules, which reabsorb the bulk of the filtrate, widened in T. savignii but narrowed in U. aegyptia. The distal tubules, important for fine-tuning ion and water balance, followed the same split pattern, expanding significantly in T. savignii while contracting in U. aegyptia. In other words, two species shrank their filtration and transport machinery while the other two enlarged theirs, a divergence the authors interpret as species-specific renal adaptation rather than a single universal hibernation phenotype.

Why would closely related desert reptiles remodel the same organ in opposite directions? The answer likely lies in their different water economies and dormancy strategies. Uromastyx aegyptia, a large herbivorous agamid that spends long periods underground, may prioritize water conservation by reducing glomerular filtration, a strategy consistent with seasonal kidney studies in the related Saharan species Uromastyx acanthinura, where winter morphology shifts with body water economy. The desert monitor, an active predator with a wide thermal niche, and the smaller agama may maintain or even expand renal structures to handle intermittent arousal and feeding. Seasonal remodeling of visceral organs is well documented in squamates, including previous work on the same gecko species showing dramatic reshaping of internal organs between seasons, so the kidney appears to be one component of a whole-body seasonal reorganization.

The biochemical side of the story centers on reactive oxygen species. Even when metabolism is depressed, cells continue to leak electrons from mitochondria, and the reoxygenation events that accompany periodic arousal can generate bursts of superoxide and other radicals that damage lipids, proteins, and DNA. The study measured malondialdehyde, or MDA, a standard end product of lipid peroxidation, as an index of oxidative damage. In all four species, MDA rose significantly during brumation, confirming that winter dormancy imposes genuine oxidative stress on reptilian kidneys. This finding aligns with a growing body of literature on hibernating frogs, turtles, toads, and mammals, and with the preparation for oxidative stress hypothesis, which proposes that animals anticipating a stressor preemptively bolster their antioxidant arsenal.

The enzymatic defenses responded, but each species in its own way. Superoxide dismutase, or SOD, which converts superoxide radicals into hydrogen peroxide, and catalase, or CAT, which then splits hydrogen peroxide into water and oxygen, both showed increased activity during brumation, with distinct patterns in each species. At the level of gene expression, SOD transcript abundance increased by 0.77-fold in U. aegyptia, 1.79-fold in V. griseus, 0.12-fold in T. savignii, and 0.51-fold in T. annularis. Catalase expression told an even more divergent tale, rising 5.24-fold in U. aegyptia, 0.86-fold in V. griseus, and 0.35-fold in T. annularis, while actually falling by 0.90-fold in T. savignii. The five-fold catalase upregulation in the spiny-tailed lizard stands out as the strongest single transcriptional response in the dataset.

When the authors sorted the species by dormancy strategy, a pattern emerged. The two obligate brumators, Uromastyx aegyptia and Varanus griseus, showed more consistent upregulation of their antioxidant genes than the facultative species Trapelus savignii and Tarentola annularis. The researchers suggest that the intensity of antioxidant defense correlates with the depth and duration of winter dormancy. An animal that commits to months of uninterrupted cold torpor faces a prolonged oxidative challenge and must invest heavily in enzymatic protection, whereas a species that brumates intermittently may rely more on behavioral buffering, such as basking during warm spells, and less on constitutive molecular defenses. This framing connects the histology and biochemistry to ecology, turning a kidney study into a window on how life histories shape stress physiology.

The broader significance of the work reaches beyond herpetology. Hibernation and brumation are among the most extreme physiological states in the animal kingdom, and understanding how dormant animals protect organs like the kidney has long interested biomedical researchers, because mammalian kidneys suffer severe injury during cold ischemia in transplantation and surgery. Studies of hibernating ground squirrels, bears, and dormice have shown that dormant kidneys are natural models of organ preservation, and the lizard data extend that comparative framework to ectotherms, which experience body temperatures that track their surroundings rather than staying warm. Reptiles may therefore harbor additional, evolutionarily independent solutions to the problem of protecting filtration tissue through cold and hypoperfusion.

There are also conservation and climate dimensions. Desert reptiles already live at the edge of their thermal tolerances, and warming winters could shorten or destabilize brumation, forcing animals to balance energy budgets in new ways, as recent work on hibernating lizards exposed to insecticides and rising temperatures has suggested. If antioxidant capacity is tuned to a particular depth and duration of dormancy, then climate-driven changes in dormancy behavior could leave kidneys mismatched to their oxidative environment. The authors collected and handled all animals under the approval of the Institutional Animal Care and Use Committee of Kafrelsheikh University, and they note that the datasets are available from the corresponding author on reasonable request. For now, the study stands as a detailed demonstration that four lizards sleeping through the same Egyptian winter are, at the level of their kidneys, solving the problem in four different ways.

Subject of Research: Renal histological changes and antioxidant enzyme responses during brumation in four Egyptian desert lizard species

Article Title: Renal histological and antioxidant response in Egyptian desert lizards during brumation

Article References: Hammad, A. R., Mahfouz, M. E., Bakr, S. M., & Alm-Eldeen, A. A. (2026). Renal histological and antioxidant response in Egyptian desert lizards during brumation. Environmental Science and Pollution Research, 33(30), 15298-15309. https://doi.org/10.1007/s11356-026-38195-9

Image Credits: AI Generated

DOI: 10.1007/s11356-026-38195-9

Keywords: brumation, desert lizards, kidney histology, oxidative stress, antioxidant enzymes, superoxide dismutase, catalase, malondialdehyde, gene expression, Uromastyx aegyptia, Varanus griseus, hibernation

Black nightshade occupies an unusual position in agriculture. Its ripe berries feed birds, its leaves are eaten as a traditional vegetable across much of Africa, and its adaptability to varied light and soil conditions has made it a fixture of smallholder plots. Yet the crop remains what scientists call a neglected and underutilized species: a landrace with no formal breeding system, grown by few farmers using traditional methods. Its most persistent problem is low yield, driven largely by the depletion of soil nutrients. That vulnerability is precisely what made it an ideal test subject for the study’s central hypothesis—that growth markers and nutrient-limitation signaling molecules can be deliberately modulated by zinc oxide nanoparticles.

The team’s starting material was as unglamorous as it gets: bean husks collected from a vendor at Council Market in Egbe, Lagos. The husks were air-dried, milled, and sieved through a 100-mesh screen before fifty grams of powder were stirred in distilled water for three hours to yield a clear brown filtrate. That extract served as the biological engine of the synthesis. When zinc nitrate solution was added and the mixture acidified, heated to 80 degrees Celsius, and finally brought to pH 11 with sodium hydroxide, the phytochemicals in the husk extract acted as reducing and stabilizing agents, coaxing zinc ions into nanoparticles and capping them in place. The process, known as green synthesis, transforms an agricultural byproduct into a vehicle for nutrient delivery while avoiding the harsh reagents of conventional chemical routes.

Characterization revealed just how small and chemically rich the resulting particles were. Transmission electron microscopy placed the average zinc oxide nanoparticle at 5.64 nanometers, with the bean husk extract particles averaging 9.19 nanometers—dimensions that confer an enormous surface-area-to-volume ratio and, with it, efficient mass transfer and targeted nutrient release. The nanoparticles adopted a wurtzite hexagonal crystal structure, confirmed by X-ray diffraction, and appeared under scanning electron microscopy as small, spherical, uniformly distributed grains. Fourier-transform infrared spectroscopy told a subtler story: the particles were not bare zinc oxide but were surface-functionalized with hydroxyl, amino, azo, silicon-containing, and aliphatic nitro groups inherited from the husk phytochemicals. Energy-dispersive spectroscopy confirmed zinc as the dominant element at 70.56 percent by weight, while silica dominated the extract at 50.25 percent.

With the materials verified, the researchers turned to the plants. In a randomized complete block design with five replications, three-week-old black nightshade seedlings were transplanted into perforated buckets of silty loam topsoil and sprayed weekly for six weeks with either zinc oxide nanoparticles or bean husk extract at concentrations of 0.5, 1.0, 1.5, and 2.0 percent, alongside a distilled-water control. Plant height and leaf number were tracked weekly, and leaf and root tissues were harvested at midday for biochemical assays. The greenhouse conditions—temperatures of 19 to 25 degrees Celsius, humidity of 50 to 80 percent, and light intensity near 460 micromoles per square meter per second—kept environmental variables tightly controlled.

The growth results were striking. Neither treatment produced a measurable effect two weeks after application, but by weeks four through six the differences became unmistakable. Plants sprayed with 1.0 percent zinc oxide nanoparticles reached an average height of 62.33 centimeters and produced 64.67 leaves—the highest values recorded for either treatment. Bean husk extract alone also promoted growth, with 2.0 percent concentrations yielding 56.83 leaves, but the nanoparticles outperformed the raw extract across the board. The pattern points to a dose window: moderate concentrations of the nanomaterial appear to improve nutrient assimilation and metabolic activity, while the raw extract, lacking the concentrated zinc payload, delivers a gentler stimulus.

Perhaps the most intriguing results came from the stress biochemistry. Control plants grown in conventional, nutrient-limited soil accumulated the highest levels of malondialdehyde—a lipid peroxidation product that marks damage to cell membranes—and hydrogen peroxide, reaching 22.67 and 21.55 micromoles per gram fresh weight in leaves and roots respectively. As nanoparticle concentrations rose, both markers fell significantly. The enzymatic antioxidant system followed a parallel, seemingly paradoxical trajectory: superoxide dismutase, catalase, ascorbate peroxidase, and glutathione reductase activities were all highest in untreated plants and dropped to their lowest levels—around 1.44 to 1.92 micromoles per minute per milligram—in leaves treated with 2.0 percent formulations.

That decline in antioxidant enzyme activity is not a sign of harm, the authors argue, but of relief. Reactive oxygen species such as hydrogen peroxide are not merely destructive byproducts; they serve as signaling molecules that plants deploy when nutrients run short, reshaping root architecture in a desperate search for sustenance. Zinc deficiency in particular is known to trigger ROS accumulation, chlorophyll degradation, impaired flowering, and yield losses. When nanoparticles restore zinc availability, the plant no longer needs to keep its antioxidant defenses on high alert, so enzyme activities subside. The simultaneous fall in ROS markers and antioxidant activity thus reads as evidence that the nanoparticles alleviated the underlying nutritional stress rather than suppressing the plant’s warning system outright—a distinction the researchers are careful to emphasize, noting that nanoparticles more commonly modulate rather than simply suppress these enzymes.

The thermal and structural data add a practical dimension. Both materials remained stable at temperatures above 290 degrees Celsius, with major decomposition events at 305 degrees for the nanoparticles and 395 degrees for the extract—stability that matters in sun-baked agricultural soils. The crystalline nature confirmed by X-ray diffraction may further contribute to nutrient absorption, and the small particle size likely facilitates absorption, entry, and translocation within plant tissues. Zinc is known to enhance metabolic processes and hormone production, while the silica abundant in the husk extract can strengthen physical structure and improve stress tolerance, suggesting the two materials played complementary roles.

The broader implications extend well beyond one leafy vegetable. Green synthesis from agricultural waste is economically viable, recycles nutrients that would otherwise be discarded, and produces amendments whose surface chemistry may enhance nutrient bioavailability and soil physical structure. For a crop grown largely by resource-poor farmers on depleted land, a foliar spray derived from market refuse that boosts height, leaf production, and stress resilience represents an appealing proposition. The authors conclude that zinc oxide nanoparticles, particularly at 1.0 percent, hold promise as sustainable soil amendments capable of enhancing growth and regulating nutrient-limitation signals. Field trials across seasons and soils will be needed to confirm that greenhouse promise translates to open-air reality, but the study offers a compelling proof of concept: the future of crop nutrition may be written in particles measured in nanometers, brewed from the leftovers of last night’s beans.

Subject of Research: Effects of green-synthesized zinc oxide nanoparticles on growth and nutrient-limitation stress signaling in black nightshade

Article Title: Differential modulation of growth markers and nutrient limitation signaling molecules mediated by zinc oxide nanoparticles in black nightshade (Solanum nigrum L.)

Article References: Ojewumi, A. W., Osifeko, O. L., Oke, O. S., Egonu, S. N., Danjumah, M. O., Solomon, F. O., Olawale, T. H., Onwordi, C. T., & Ojekale, A. B. (2026). Differential modulation of growth markers and nutrient limitation signaling molecules mediated by zinc oxide nanoparticles in black nightshade (Solanum nigrum L.). Discover Chemistry, 3(1), Article 486. https://doi.org/10.1007/s44371-026-00947-4

Image Credits: AI Generated

DOI: 10.1007/s44371-026-00947-4

Keywords: zinc oxide nanoparticles, black nightshade, Solanum nigrum, green synthesis, bean husk extract, reactive oxygen species, antioxidant enzymes, nanofertilizer, soil amendment, nutrient limitation, malondialdehyde, sustainable agriculture

The research team, led by Feng Zhang and Yanyan Wang of Guangdong Ocean University together with colleagues at South China Agricultural University and the Zhanjiang Academy of Agricultural Sciences, subjected peanut seedlings to high selenium stress and then interrogated the plants with two complementary high-throughput technologies. Transcriptome sequencing revealed which genes were switched on or off in roots and leaves, while metabolomic profiling catalogued the small molecules whose concentrations rose or fell in response. By overlaying the two datasets, the researchers could trace causal threads from gene activity through enzyme function to the chemical end products that ultimately determine whether a cell survives. The approach, known as integrated multi-omics, is rapidly becoming the gold standard for decoding stress responses in crops, because neither gene expression nor metabolite abundance alone tells the full story.

The physiological damage caused by excess selenium was unmistakable. Seedlings exposed to toxic concentrations showed significantly inhibited root growth, with measurable reductions in total root length and root surface area, the two parameters that govern how effectively a plant explores the soil for water and nutrients. Leaf area also shrank, curtailing the photosynthetic surface available to fuel growth. At the cellular level, the selenium treatment threw the antioxidant enzyme system out of balance in both organs. When the balance of enzymes such as superoxide dismutase and peroxidase is disrupted, reactive oxygen species accumulate unchecked, and one of the most reliable fingerprints of that damage is malondialdehyde, or MDA, a breakdown product of lipid peroxidation. MDA levels climbed in both roots and leaves, confirming that selenium stress was literally oxidizing the fatty membranes that enclose every cell.

Selenium also wreaked havoc on the plant’s mineral nutrition. The researchers documented disturbances in the absorption and transport of essential ions, including zinc, iron and boron, three micronutrients that peanut plants need for enzyme function, chlorophyll synthesis and cell wall construction. This kind of ionic interference is a classic feature of heavy metal and metalloid toxicity: the transporters that normally ferry beneficial ions across root membranes can be hijacked or competitively inhibited by chemically similar toxic elements, and once the ionome is destabilized, downstream metabolism begins to unravel. The finding has practical implications for selenium biofortification programs, because it suggests that simply adding more selenium to soil or irrigation water risks creating secondary deficiencies that could compromise both yield and nutritional quality.

Beneath these visible symptoms, the molecular data revealed the scale of the plant’s emergency response. Transcriptomic analysis identified 3,578 differentially expressed genes in roots and 1,331 in leaves, a striking asymmetry that makes sense given that roots are the first point of contact with selenium in the growth medium. The affected genes clustered around three major functional themes: antioxidant regulation, ion transport and secondary metabolism. Meanwhile, metabolomic analysis detected 582 differentially abundant metabolites in leaves and 846 in roots, spanning amino acids, fatty acids and phenolic compounds. The sheer number of coordinated changes underscores that selenium toxicity is not a single-hit injury but a systemic challenge that reorganizes a large fraction of the plant’s metabolic economy.

When the researchers ran enrichment analyses on both datasets, one pathway stood out in both roots and leaves: phenylpropanoid metabolism. This pathway is one of the most versatile chemical factories in the plant kingdom. It begins with the amino acid phenylalanine, which the enzyme phenylalanine ammonia-lyase, or PAL, converts into cinnamic acid by stripping off an ammonia group. That deamination step is widely regarded as the committed gateway into the pathway, and from cinnamic acid a cascade of hydroxylations, methylations, ligations and reductions branches outward to produce an astonishing diversity of compounds: lignin that stiffens cell walls, flavonoids that screen ultraviolet light, coumarins that deter herbivores, and a broad arsenal of phenolic acids that quench reactive oxygen species. In the selenium-stressed peanut seedlings, this assembly line was visibly revved up.

The transcriptomic data pinpointed exactly which gears of the pathway were turning. Key biosynthetic genes, including PAL, cinnamyl alcohol dehydrogenase, known as CAD, and 4-coumarate-CoA ligase, or 4CL, were differentially expressed under high selenium stress. Each of these enzymes occupies a strategic position: PAL controls entry into the pathway, 4CL activates cinnamic acid derivatives by attaching coenzyme A, preparing them for downstream branching, and CAD catalyzes the final reduction steps that feed into lignin biosynthesis. The coordinated regulation of these genes translated into measurable shifts in pathway metabolites, with compounds such as cinnamic acid and coumaroylquinic acid changing in abundance in the stressed tissues. Coumaroylquinic acid, a phenolic acid ester, belongs to the class of antioxidants that plants mobilize to neutralize the reactive oxygen species generated by abiotic stress, and its accumulation alongside the upregulated biosynthetic genes suggests a direct defensive function.

The logic of this response is elegant. Selenium toxicity, like that of many excess metals, inflicts much of its damage indirectly through oxidative stress: the element disrupts electron transport chains and enzyme active sites, causing cells to overproduce reactive oxygen species that attack DNA, proteins and membranes. Rather than relying solely on its enzymatic antioxidant system, which the study showed had been thrown off balance, the plant appears to compensate by flooding its tissues with non-enzymatic phenolic antioxidants manufactured by the phenylpropanoid pathway. These molecules can donate electrons or hydrogen atoms to stabilize free radicals, and some can also chelate metal ions, potentially reducing the mobility of selenium itself within tissues. In parallel, increased flux toward lignin precursors may reinforce cell walls in roots, helping to seal off the point of entry and maintain structural integrity while growth slows.

For agricultural scientists, the study offers more than a mechanistic curiosity. Peanuts are a staple oilseed and food legume grown across vast areas of Asia and Africa, and they are one of the crops targeted for selenium biofortification because selenium-enriched peanut products could help address dietary selenium deficiency in human populations. Understanding which genes and metabolites confer tolerance to selenium excess gives breeders molecular markers they can use to select varieties that accumulate beneficial amounts of selenium in seeds without suffering toxicity in vegetative tissues. The authors explicitly frame their findings as a theoretical foundation for breeding selenium-tolerant peanut varieties, and the specific candidates they identified, from PAL and 4CL to the accumulating phenolic metabolites, provide a concrete starting point for marker-assisted selection or even gene editing approaches.

The work also adds to a growing body of evidence that the phenylpropanoid pathway functions as a universal stress hub in plants, recruited not only against pathogens and herbivores but against abiotic insults ranging from drought and salinity to heavy metal contamination. What makes this study particularly valuable is its tissue-resolved design: by analyzing roots and leaves separately, the researchers captured the division of labor within a single plant, where roots mount the larger transcriptional response while both organs converge on the same defensive chemistry. As climate variability and soil chemistry changes push crops into more marginal growing conditions, decoding these internal defense circuits will become ever more important, and the humble peanut, it turns out, has been running one of the most sophisticated chemical defense programs in biology all along.

Subject of Research: Molecular response of the phenylpropanoid biosynthesis pathway in peanut seedlings under high selenium stress

Article Title: The mechanism of the phenylpropanoid biosynthesis pathway in peanut seedlings responding to high Se stress

Article References: Zhang, F., Wang, Y., Liang, Z., Chen, T., Feng, E., Zhang, R., Xie, Q., Hu, H., Xue, Y., & Liu, Y. (2026). The mechanism of the phenylpropanoid biosynthesis pathway in peanut seedlings responding to high Se stress. BMC Plant Biology. https://doi.org/10.1186/s12870-026-10042-6

Image Credits: AI Generated

DOI: 10.1186/s12870-026-10042-6

Keywords: peanut, selenium toxicity, phenylpropanoid biosynthesis, transcriptomics, metabolomics, oxidative stress, antioxidant enzymes, Arachis hypogaea, plant stress responses, secondary metabolism, ion transport, malondialdehyde

The team focused on pak choi, a fast-growing leafy brassica that is both economically important across Asia and notoriously sensitive to salinity. Their experimental system applied food waste leachate to soil at a range of rates and then measured how the plants responded. The first and arguably most consequential finding was a clear threshold. Below 125 milliliters of leachate per kilogram of soil, pak choi grew reasonably well, drawing on the leachate’s nutrient load. Above that critical rate, growth collapsed. The researchers identified 125 mL/kg as the point beyond which severe growth suppression set in, a boundary that any future fertilization protocol built on food waste leachate would need to respect.

To rescue plants grown near or at this salinity limit, the team turned to two by-products of industrial fermentation. The first, labeled YM in the study, is corn steep liquor concentrate, a concentrated steeping water from corn wet milling that is loaded with amino acids, soluble nitrogen, vitamins and growth-promoting compounds. The second, labeled TM, is molasses fermentation liquid, a sugary, antioxidant-rich residue from fermentation processes that use molasses as feedstock. Both materials are produced in enormous volumes worldwide, and both are typically treated as low-value waste streams. The researchers hypothesized that their physiological effects on stressed plants would be complementary rather than redundant, and that combining them could produce benefits larger than either could deliver alone.

The hypothesis held up in striking detail. When applied individually, each agent helped, but in visibly different ways. Corn steep liquor concentrate proved to be a root architect: pak choi treated with YM expanded its root volume by 89.2 percent compared with salt-stressed controls. A larger, more voluminous root system is not merely cosmetic. It increases the surface area available for water and nutrient uptake, which directly counteracts the osmotic stress that salinity imposes, since salty soil effectively holds water away from plant roots. Molasses fermentation liquid, by contrast, acted as a cellular defense agent. Plants receiving TM showed a 35.1 percent reduction in malondialdehyde, a standard biomarker of lipid peroxidation. Lower malondialdehyde means that the membranes lining plant cells were being oxidized and damaged far less, indicating that TM bolstered the plant’s antioxidant machinery against the oxidative burst that salt stress triggers.

These distinct mechanisms set the stage for the study’s central experiment: dose-dependent combination trials. The researchers paired the two agents at low concentrations, a formulation designated YM0.1 plus TM0.1, and at higher concentrations, YM0.5 plus TM0.5, to test whether the complementary actions would compound. The low-dose combination delivered the study’s headline result. Pak choi grown with the paired low-dose treatment under food waste leachate stress produced 27.7 percent more shoot dry weight than stressed plants without the combination. Crucially, this figure exceeded the maximum benefit achievable by either agent applied alone at any dose tested. The combination also maximized the study’s comprehensive growth index, an integrated measure that folds together multiple growth parameters into a single score of plant performance.

The high-dose combination told a cautionary tale. When YM and TM were both applied at the higher rate, the collaborative advantage vanished. Root growth indices for the high-dose combination actually fell below those of plants receiving the high dose of corn steep liquor concentrate alone. The authors attribute this reversal to secondary osmotic stress: piling two organic amendments onto soil already carrying a heavy salt load from the leachate pushed the total osmotic pressure of the root zone past what pak choi could tolerate. In other words, the very materials meant to relieve stress became stressors themselves when overdosed. The lesson is that in saline systems, more of a good thing is not better, and the interactions between amendments are dose-dependent in a way that single-agent trials cannot reveal.

The physiological logic behind the low-dose synergy is worth unpacking. Salinity harms plants through two intertwined pathways. The first is osmotic: salt in the soil solution makes it harder for roots to extract water, slowing cell expansion and overall growth. The second is ion-specific and oxidative: excess sodium and chloride ions interfere with enzyme function and nutrient balance, prompting the accumulation of reactive oxygen species that attack membranes, proteins and DNA. Corn steep liquor concentrate, with its rich supply of organic nitrogen compounds and growth factors, appears to attack the first pathway by building a bigger, more efficient root system that can mine water from a hostile soil. Molasses fermentation liquid attacks the second, supplying sugars and antioxidant precursors that help the plant quench free radicals before they shred cell membranes. Applied together at low doses, the two agents cover both fronts of the salt assault simultaneously, which is why their combined effect on biomass outran either single treatment.

The broader significance of the work lies in waste circularity. Food waste leachate, corn steep liquor and molasses fermentation liquid are all by-products of urban and industrial systems, generated in quantities that often overwhelm disposal infrastructure. Converting them into a coordinated fertilization strategy would close a nutrient loop: nutrients harvested from food scraps and fermentation plants would flow back into food production instead of into waterways or landfills. The study’s identification of a precise threshold, 125 mL/kg of leachate, and a precise formulation, low-dose YM plus TM, transforms what has been a qualitative idea, that organic amendments can ease salt stress, into a quantitative protocol that farmers and waste managers could actually implement. The authors frame this as a viable theoretical and practical framework for turning hypersaline organic wastes into sustainable agricultural resources without triggering secondary metabolic imbalances.

There are, of course, caveats that temper immediate field application. The experiments were conducted under controlled conditions with defined leachate and amendment compositions, and real food waste leachate varies enormously in salinity, nutrient content and organic load depending on its source and season. The dose thresholds established here would need recalibration for different soils, climates and crops, and long-term trials would need to confirm that repeated applications do not gradually accumulate salts or alter soil microbial communities in undesirable ways. The study’s own demonstration that high-dose combinations backfire underscores how carefully any scaling effort must tread. Still, the dose-dependent framework the researchers built, mapping where benefit peaks and where it collapses, is exactly the kind of quantitative scaffolding that turns a promising laboratory observation into an agronomic tool.

What makes the finding resonate beyond agronomy is its demonstration of a general principle: the value of a waste-derived biostimulant is not fixed but emergent, depending on what it is paired with and how much is applied. Two industrial residues, each individually modest in its benefit, became more than the sum of their parts when combined at the right dose, and less than useless when combined at the wrong one. As climate change drives soil salinization across agricultural regions and as food systems search for ways to recycle their own effluents, studies like this one suggest that the answer may lie not in any single miracle amendment but in the deliberate, dose-calibrated orchestration of the wastes we already produce. For pak choi growers wrestling with saline irrigation water or leachate-based fertilizers, the message is concrete: pair your corn steep liquor with your molasses liquid, keep both doses low, and stay under the salt threshold.

Subject of Research: Mitigating salinity stress in pak choi using combined industrial fermentation wastes and food waste leachate

Article Title: Alleviating salinity-induced growth inhibition in pak choi through the complementary effects of industrial fermentation wastes and food waste leachate in soil–plant interactions

Article References: Wu, M., Yan, Y., Han, G., Fiore, L., Ahmed, W., Chen, Q., & Mu, K. (2026). Alleviating salinity-induced growth inhibition in pak choi through the complementary effects of industrial fermentation wastes and food waste leachate in soil–plant interactions. Plant and Soil. https://doi.org/10.1007/s11104-026-09163-6

Image Credits: AI Generated

DOI: 10.1007/s11104-026-09163-6

Keywords: pak choi, soil salinity, food waste leachate, corn steep liquor, molasses fermentation liquid, plant biostimulants, oxidative stress, malondialdehyde, root architecture, waste valorization, sustainable agriculture, dose threshold

Arbuscular mycorrhizal fungi, or AMF, are among the most successful symbionts on Earth, forming associations with roughly 80 percent of plant species, including most agricultural crops. These fungi penetrate or envelop plant roots and extend a web of filaments, called extraradical mycelium, far into the surrounding soil. Through this network they draw in water and hard-to-reach nutrients, particularly phosphorus, whose poor mobility in soil often limits crop growth. In exchange, the plant supplies the fungus with carbon derived from photosynthesis. For decades, agronomists have exploited this partnership to improve crop tolerance to drought, salinity, and nutrient poverty, but the consequences for the wider rhizosphere microbiome, the teaming bacterial ecosystem hugging the root surface, have remained poorly resolved, especially under low-nutrient conditions.

To probe this question, the research team grew tobacco, Nicotiana tabacum, in pots filled with a low-fertility loess-derived soil collected near the university in Anhui Province. The soil was deliberately lean: ammonium nitrogen measured just 3.37 milligrams per kilogram and nitrate nitrogen 2.16 milligrams per kilogram, with modest organic matter of 15.3 grams per kilogram. Before planting, the soil was autoclaved at 121 degrees Celsius for two hours to eliminate native fungi and other microbes, creating a clean slate. Half the pots received 30 grams of an inoculum containing C. etunicatum spores, mycelia, and colonized root fragments at a density of five spores per gram; the control pots received an equal amount of sterilized inoculum to keep background conditions identical. The plants then grew for 60 days in a greenhouse cycling between 28 and 18 degrees Celsius, with three biological replicates per treatment.

The growth results were unambiguous. Compared with uninoculated controls, AMF-colonized tobacco showed significantly greater aboveground and belowground fresh weight and taller plants, with root biomass increasing by 12.90 percent and spore density in the soil rising by 4.51 percent. More striking were the changes inside the plant’s stress-response machinery. Activities of the antioxidant enzymes catalase and superoxide dismutase rose significantly, while levels of malondialdehyde, a molecular marker of lipid peroxidation and membrane damage, fell. Because malondialdehyde accumulates when reactive oxygen species assault cell membranes under stress, its decline indicates that the fungal partnership had measurably blunted the oxidative injury that nutrient scarcity inflicts on tobacco tissue.

To see whether these physiological gains were mirrored in the root-zone microbiome, the team sequenced the V4 region of the bacterial 16S rRNA gene from rhizosphere soil using the Illumina MiSeq platform, processing the reads through the Deblur pipeline to generate amplicon sequence variants. Phylogenetic analysis of the 100 most abundant genera identified twelve core bacterial phyla, dominated by Proteobacteria with 28 genera, Chloroflexi with 16, Actinobacteriota with 14, and Myxococcota with 12. Fungal inoculation significantly reshaped the community structure, enriching beneficial groups across these phyla. Among the genera that shifted most dramatically, the AMF-treated soils favored unclassified members of the Xanthomonadaceae along with Agromyces, Phenylobacterium, and Solimonas, whereas the control soils were dominated by Arenimonas, Sphingoaurantiacus, and Azohydromonas.

Each enriched phylum brings a distinct ecological skill set. Proteobacteria, among the most diverse bacterial phyla known, act as central regulators of global carbon, nitrogen, and sulfur cycling, and their nitrogen-fixing members can enhance soil fertility through nitrification-related processes. Actinobacteriota solubilize phosphorus and mineralize organic nutrients while producing extracellular metabolites that suppress pathogens and sometimes function as growth regulators. Chloroflexi, filament-forming anaerobes that degrade complex carbohydrates and peptides, likely metabolize the organic deposits left by fungal hyphae, explaining their rise in the mycorrhizal rhizosphere. Myxococcota, meanwhile, are predators within the mycelial food web, consuming the carbon-rich compounds that AMF transport from the plant. Together, these groups form a functional support crew whose presence correlates with improved nutrient acquisition and stress tolerance in the host.

Perhaps the most visually compelling evidence came from co-occurrence network analysis, which maps which bacterial taxa tend to appear together and infers cooperative or competitive relationships. The networks differed sharply between treatments. Although the control network contained slightly more nodes and edges, the AMF network showed a higher average clustering coefficient, 0.713 versus 0.705, and, critically, far fewer negative correlations between species. In the control network, 96.13 percent of nodes were peripheral with little topological significance, while the AMF network pushed that proportion to 97.31 percent but concentrated its interactions more centrally, with node-level measures of degree, betweenness, and modularity all significantly higher. The researchers interpret this architecture as evidence that fungal inoculation drives the community toward greater microbial synergy, with more positive, mutualistic links replacing antagonistic ones.

Functional profiling reinforced the picture. Using STAMP statistical comparisons, the team found that seven representative microbial functions differed significantly between treatments, with AMF-treated soils showing enhanced abundance of genes associated with signal transduction and prokaryotic cell communities. Mantel tests revealed that bacterial alpha diversity was tightly linked to cell motility, signal transduction, and prokaryotic community functions, with correlation coefficients exceeding 0.20 at statistical significance. The strongest positive functional correlations appeared among amino acid metabolism, carbohydrate metabolism, and cofactor and vitamin metabolism, suggesting that the enriched community was not merely more diverse but metabolically more capable.

To tie these threads together causally, the researchers built a structural equation model linking the fungus, bacterial network structure, soil and plant enzyme activity, community diversity, community function, and plant antioxidant capacity. The model showed that AMF exerted strong positive effects on bacterial network structure, with a standardized path coefficient of 0.840, and on soil enzyme activity, at 0.573, both highly significant. Plant enzyme activity positively influenced both bacterial community function and the plant’s antioxidant capacity, while bacterial community diversity and function in turn boosted antioxidant defenses. Notably, bacterial community diversity exerted a stronger total effect on antioxidant capacity than the fungus itself, implying that the fungus works largely through its microbial intermediaries rather than on the plant directly.

The implications extend well beyond tobacco, a crop of substantial economic importance in China and one of the most intensively studied mycorrhizal hosts. As agriculture confronts the twin pressures of rising fertilizer costs and the environmental toll of over-application, biological strategies that coax more productivity from lean soils are increasingly attractive. This study demonstrates that a mycorrhizal inoculant does not simply feed the plant; it curates a bacterial entourage, recruiting nutrient cyclers, pathogen suppressors, and carbon scavengers while knitting them into a stabler, more cooperative network. The finding that community diversity, not the fungus alone, is the strongest driver of antioxidant protection suggests that future biofertilizers may need to be designed as ecosystems rather than single strains. For now, the humble threads of a soil fungus have been shown to conduct an entire underground orchestra, and the plant, quite literally, reaps the benefits.

Subject of Research: Effects of arbuscular mycorrhizal fungal inoculation on the rhizosphere bacterial community and antioxidant capacity of tobacco under low-nutrient conditions

Article Title: Effect of Claroideoglomous etunicatums on rhizosphere bacterial community of tobacco under low nutrient conditions

Article References: Chen, J., Geng, X., Zhang, Q., Lin, K., Li, Z., Wang, B., Xiao, Q., & Li, X. (2025). Effect of Claroideoglomous etunicatums on rhizosphere bacterial community of tobacco under low nutrient conditions. Advanced Biotechnology, 3(3), Article 22. https://doi.org/10.1007/s44307-025-00071-x

Image Credits: AI Generated

DOI: 10.1007/s44307-025-00071-x

Keywords: arbuscular mycorrhizal fungi, Claroideoglomus etunicatum, tobacco, rhizosphere, bacterial community, 16S rRNA sequencing, co-occurrence network, antioxidant enzymes, malondialdehyde, soil microbiome, low nutrient stress, structural equation modeling

Fluoride occupies an unusual position in public health. Deliberately added to drinking water in controlled amounts to protect teeth, it also enters the environment through industrial processes ranging from phosphate fertilizer production to aluminum smelting, coal combustion, and the manufacture of glass, ceramics, and bricks. In regions with fluoride-rich minerals, well water can contain concentrations approaching 10 milligrams per liter, far above levels considered desirable. Food contributes as well: vegetables grown in contaminated fields, fish, and especially tea can carry appreciable fluoride loads, with dry tea leaves averaging around 100 milligrams per kilogram. Because the element is non-biodegradable, exposure is essentially continuous for many populations, making the search for practical protective strategies a matter of genuine urgency.

The biological problem with excess fluoride is that it behaves as a pro-oxidant. When fluoride intake overwhelms the body’s antioxidant defenses, free radicals accumulate faster than they can be neutralized, a state known as oxidative stress. This stress attacks the macromolecules of the cell, peroxidizing membrane lipids, damaging proteins, and breaking DNA strands. Previous studies in mice given sodium fluoride in drinking water showed depleted glutathione in the liver, along with DNA strand breaks, micronucleus formation, and the appearance of oxidized DNA adducts such as 8-hydroxy-2-deoxyguanosine. Such damage can push cells toward genotoxicity, somatic mutation, and apoptosis, the controlled self-destruction that follows irreparable injury. The liver, as the body’s principal detoxification organ, and the kidney, which receives roughly a fifth of cardiac output and concentrates circulating toxins, are particularly vulnerable targets.

To test whether Phyllanthus amarus could intervene, the team harvested leaves from Umuosele community in Amai, Nigeria, dried and powdered them, and extracted 500 grams of the material in methanol over 48 hours. The crude extract was then separated by liquid-liquid partitioning into fractions of differing polarity, using n-hexane, diethyl ether, n-butanol, methanol, and water. Yields varied considerably, with the methanol crude extract giving 37.62 percent, the methanol fraction 28.40 percent, and the aqueous fraction only 7.30 percent. The researchers selected the crude extract, the highest-yielding methanol fraction, and the lowest-yielding aqueous fraction for animal testing, dissolving each in 5 percent Tween 80 to a working concentration of 0.11 grams per milliliter.

Safety came first. In a preliminary lethal dose assessment involving sixty rats, no deaths occurred at oral doses from 100 to 1600 milligrams per kilogram of body weight across the fractions and crude extract. Rats receiving the higher doses showed reduced locomotion, but the 400 milligram per kilogram dose was well tolerated and even associated with normal hair growth, so the team adopted it for the main experiment. Thirty male Wistar rats, aged seven to nine weeks, were then divided into six groups of five. One group served as an untreated control, two groups received sodium fluoride alone or with the Tween 80 vehicle, and three groups received sodium fluoride alongside either the aqueous fraction, the methanol fraction, or the crude extract. Sodium fluoride was dosed orally at 25 milligrams per kilogram per day, and all treatments ran concurrently for 28 days before the animals were sacrificed and their tissues analyzed.

The results were striking. Rats exposed to sodium fluoride alone showed significant decreases in the activities of the antioxidant enzymes superoxide dismutase, catalase, glutathione peroxidase, and glutathione-S-transferase, along with depleted levels of reduced glutathione, in both liver and kidney tissue. At the same time, malondialdehyde, the standard chemical marker of lipid peroxidation and membrane damage, rose significantly. Histological examination confirmed the biochemical picture: livers of fluoride-exposed rats showed necrosis, while kidneys displayed detachment of the glomerulus from Bowman’s capsule, clear signs of structural injury consistent with fluoride-induced oxidative stress.

Co-treatment with Phyllanthus amarus reversed much of this damage. In the groups receiving the aqueous fraction, the methanol fraction, or the crude extract, glutathione levels and the activities of all four antioxidant enzymes rose significantly compared with the fluoride-only animals, while malondialdehyde concentrations fell. The authors attribute this rescue effect to the plant’s rich polyphenol content, which can scavenge free radicals and thereby preserve the metal-dependent antioxidant enzymes that fluoride disrupts. Superoxide dismutase converts the superoxide anion into hydrogen peroxide, which catalase and glutathione peroxidase then eliminate, while glutathione-S-transferase conjugates electrophilic toxins for excretion. By keeping this enzymatic chain intact, the extracts appear to have restored the oxidative balance that fluoride had tipped.

Perhaps the most consequential finding concerned DNA. Using a diphenylamine-based fragmentation assay, the researchers measured how much DNA in liver and kidney tissue had been broken into pieces, a sensitive indicator of genotoxic injury. Fluoride-exposed rats showed markedly elevated DNA fragmentation in both organs, but the three treatment groups showed significant reductions. Notably, the crude extract outperformed the methanol fraction, a difference the authors suggest reflects the higher concentration of bioactive compounds present in the unfractionated preparation. The team proposes that the plant’s antioxidants reduce the electrophilic chemicals that would otherwise attack DNA, preventing the multiple lesions that fluoride toxicity can produce.

The study is not without limitations, which the authors acknowledge candidly. Financial constraints prevented characterization of the specific active constituents in the crude extract and fractions, so the precise molecules responsible for the protective effect remain unidentified. The work was also conducted in a small number of animals over a single 28-day window, and findings in rats do not automatically translate to humans. Nevertheless, the researchers argue that Phyllanthus amarus leaves merit further investigation as an affordable and accessible alternative for managing renal and hepatic disorders linked to fluoride and other oxidative stressors, particularly in regions where fluoride contamination of water and food is endemic.

For a plant that traditional healers have long prescribed for ailments ranging from hepatitis and malaria to diarrhea and skin disease, the new data provide a mechanistic footing for at least one of its claimed benefits. If subsequent studies can identify the active compounds and confirm protective effects at realistic exposure levels, a weed that grows freely across the tropics could become a low-cost ally against an environmental toxin that no one can entirely avoid. For now, the message from the Nigerian laboratory is clear: in rats at least, the chemistry of Phyllanthus amarus stands between fluoride and the fragile DNA of the liver and kidney.

Subject of Research: Protective effects of Phyllanthus amarus extracts against sodium fluoride-induced oxidative stress and DNA damage in rat liver and kidney

Article Title: Impact of Phyllanthus amarus on fragmented DNA and antioxidant activity of rats exposed to sodium fluoride

Article References: Ibobo, G. O., Okpoghono, J., & Onyesom, I. (2025). Impact of Phyllanthus amarus on fragmented DNA and antioxidant activity of rats exposed to sodium fluoride. Discover Toxicology, 2(1), Article 2. https://doi.org/10.1007/s44339-025-00017-x

Image Credits: AI Generated

DOI: 10.1007/s44339-025-00017-x

Keywords: Phyllanthus amarus, sodium fluoride, oxidative stress, DNA fragmentation, antioxidant enzymes, lipid peroxidation, malondialdehyde, glutathione, hepatotoxicity, nephrotoxicity, polyphenols, toxicology

Allelopathy, the phenomenon in which plants release biochemicals that suppress or stimulate their neighbors, has fascinated ecologists for decades and is increasingly viewed as a source of environmentally benign herbicides. Allelochemicals, which include phenolic acids, flavonoids and other secondary metabolites, interfere with germination, photosynthesis, respiration and nitrogen assimilation in susceptible species. What distinguishes the new study is its effort to connect the full chain of events, from the first burst of reactive oxygen species to the activities of specific enzymes of nitrogen metabolism and the phenylpropanoid pathway, in two weed species that had never previously been analyzed together under lupin allelopathy. The authors argue that this integrated view is essential if allelopathic plants are ever to be deployed deliberately as bioherbicides rather than admired as botanical curiosities.

The team grew seedlings of both weeds and treated them with aqueous leaf extract of Lupinus termis at a range of concentrations, then measured a battery of indicators spanning seed germination, oxidative stress markers, antioxidant defenses and metabolic enzyme activities. The earliest and most striking signal was oxidative. Levels of malondialdehyde, the standard fingerprint of lipid peroxidation, rose markedly in the leaves of both species, as did the concentrations of superoxide radicals and hydrogen peroxide. These reactive oxygen species are normal byproducts of a working metabolism, but when their production outpaces their removal they attack membranes, proteins and nucleic acids. The accumulation of all three markers after extract treatment indicated that the allelochemicals in lupin leaves had pushed the weeds’ cellular chemistry into a state of genuine oxidative stress rather than a transient, easily buffered fluctuation.

Plants are not defenseless against such assaults, and the study documented the weeds’ countermeasures in detail. Total phenolic and flavonoid contents increased pronouncedly in both species following exposure to the lupin extract, a defensive metabolic adjustment that reflects activation of the phenylpropanoid pathway, the assembly line that converts phenylalanine into a diverse arsenal of protective compounds. Phenolics can directly scavenge radicals, chelate metal catalysts of oxidation and reinforce cell walls, so their accumulation is a classic sign that a plant perceives chemical stress and is investing resources in containment. The researchers also tracked the four central enzymes of the antioxidant system: superoxide dismutase, which converts superoxide radicals into hydrogen peroxide; ascorbate peroxidase, which uses ascorbate to reduce that peroxide inside chloroplasts; catalase, which decomposes peroxide in peroxisomes; and glutathione reductase, which regenerates the reduced glutathione that feeds the ascorbate-glutathione cycle.

The behavior of these enzymes turned out to be sharply concentration-dependent, and this is where the study delivers its most instructive twist. At lower concentrations of the lupin extract, the activities of superoxide dismutase, ascorbate peroxidase, catalase and glutathione reductase were markedly stimulated in both weed species, suggesting an adaptive response to moderate oxidative stress in which the antioxidant machinery is upregulated to match the increased radical burden. At higher concentrations, however, the same enzymes were significantly suppressed, indicating direct inactivation or structural damage under excessive allelochemical pressure. In other words, a modest dose of lupin chemistry acts like a training exercise that the weeds can withstand, while a heavy dose disables the very enzymes that would otherwise save them. This biphasic pattern mirrors findings from other allelopathy systems and underscores why concentration control matters enormously in any practical application.

Photosynthetic pigments provided a second window into the damage. The study assessed chlorophylls and carotenoids in the treated leaves, following the established understanding that allelopathic phenolics can inhibit chlorophyll accumulation both by suppressing its synthesis and by accelerating its degradation through enzymes such as chlorophyllase. Pigment loss compounds the oxidative problem, because chloroplasts are simultaneously the main source of reactive oxygen species under stress and a primary victim of them. When the photosynthetic apparatus is compromised, energy interception becomes inefficient, excitation pressure builds in the light-harvesting complexes, and the resulting electron leakage generates still more superoxide. The combination of declining pigments and rising lipid peroxidation in the treated weeds paints a coherent picture of a photosynthetic system under escalating, self-amplifying stress.

Beyond the antioxidant story, the researchers extended their analysis to nitrogen metabolism, an angle that gives the work much of its originality. Nitrogen assimilation depends on a chain of enzymes including nitrate reductase, glutamine synthetase and glutamate synthase, which together convert soil nitrate into the amino acids from which proteins, nucleic acids and chlorophyll are built. Perturbing this chain starves a plant of the building blocks needed to repair stress damage, creating a second front of vulnerability. The study’s novelty, according to the authors, lies precisely in linking the concentration-dependent oxidative stress responses with alterations in nitrogen metabolism and in the enzymes of the phenylpropanoid pathway, thereby showing how a single allelochemical insult reverberates through several biochemical networks at once rather than hitting one target in isolation.

The implications for weed management are considerable. Synthetic herbicides face mounting problems of resistance, residues and regulatory restriction, and allelopathy is repeatedly proposed as a source of bioherbicides and of crop rotations that naturally suppress weeds. Lupinus termis is already cultivated as a grain and forage legume, so its residues are abundantly available as mulch, extract or soil amendment. If the concentration-dependent pattern observed here holds in field settings, lupin-derived preparations could be tuned to push target weeds past the threshold where their antioxidant defenses fail, while the same chemistry at lower intensity might even prime neighboring crops. The authors are careful to frame the work as a foundation: the study is the first to examine lupin leaf extract against these two species together, and translating the greenhouse biochemistry into agronomic practice will require dose calibration, soil chemistry considerations and validation against non-target organisms.

The research also contributes to a broader mechanistic debate about how allelochemicals actually work. Recent reviews have emphasized that perturbation of reactive oxygen species metabolism is a recurring element in the mode of action of many allelochemicals, and the lupin study fits that framework neatly while adding metabolic depth. The biphasic enzyme response suggests that hormesis, the phenomenon in which low doses of a stressor stimulate and high doses inhibit, may govern not only growth but the antioxidant apparatus itself. For biochemists, that makes the four antioxidant enzymes a sensitive dosimeter of allelochemical pressure; for agronomists, it means the difference between a stimulatory and a lethal application may be narrow and must be measured rather than assumed.

What remains to be seen is whether the same signatures appear under natural soil conditions, where microbial degradation, adsorption and leaching continuously reshape the effective dose of allelochemicals. The authors report that the underlying data are available from the corresponding author upon reasonable request, and they declare no competing interests and no external funding for the work. As a piece of basic plant physiology, however, the study stands on its own: it demonstrates that a common Mediterranean lupin carries leaf chemistry strong enough to flood two tenacious weeds with reactive oxygen species, provoke a costly phenolic counterattack, and ultimately break the enzymatic shield that keeps their metabolism running. In the quiet chemical warfare waged between plants, the lupin has just been shown to hold a formidable arsenal.

Subject of Research: Allelopathic effects of Lupinus termis leaf extract on oxidative stress, antioxidant defenses and metabolism of two weed species

Article Title: Allelopathic influence of Lupinus termis leaf extract on photosynthetic pigments, antioxidants and metabolic activities in Euphorbia helioscopia and Chenopodium murale

Article References: El-Shora, H. M., Tawfik, M. M., El-Hosary, E. G., El-Sayyad, G. S., Elkelish, A., & Abdulhakim, K. N. (2026). Allelopathic influence of Lupinus termis leaf extract on photosynthetic pigments, antioxidants and metabolic activities in Euphorbia helioscopia and Chenopodium murale. Plant Biosystems, 160(4), Article 233. https://doi.org/10.1007/s44473-026-00217-2

Image Credits: AI Generated

DOI: 10.1007/s44473-026-00217-2

Keywords: allelopathy, Lupinus termis, Euphorbia helioscopia, Chenopodium murale, oxidative stress, antioxidant enzymes, reactive oxygen species, malondialdehyde, phenylpropanoid pathway, nitrogen metabolism, bioherbicides, photosynthetic pigments

Lipid oxidation is one of the chief enemies of food quality. When unsaturated fatty acids react with oxygen, they form hydroperoxides, aldehydes, and a cascade of secondary products that ruin flavor, erode nutritional value, and raise safety concerns. Two measurements dominate the monitoring of this decay: the peroxide value, which tracks the early stage of peroxidation, and malondialdehyde, or MDA, a hallmark of advanced oxidative chain-scission. Photooxidation, in which light energizes the process, is among the most damaging pathways, yet the precise role of heme proteins in accelerating it has remained surprisingly underexplored.

The research team, led by Mahdi Hajimohammadi of Kharazmi University in collaboration with colleagues in Iran and Iraq, set out to close that gap. Rather than isolating purified hemoglobin, they used intact erythrocyte suspensions derived from commercially supplied sheep blood, preserving the protein’s native structure and redox environment. This choice made the system biologically realistic: hemoglobin remained embedded in the matrix it normally occupies, at the boundary between an aqueous phase and the oil droplets of a commercial canola oil emulsion. The mixture was illuminated by a solar simulator, an array of 276 LED lamps spanning 380 to 780 nanometers and delivering an intensity of roughly 59,660 lux, closely matching the spectrum of natural sunlight.

The results were striking. After 2.5 hours of irradiation in the presence of air, the peroxide value of the oil climbed to 9.7 milliequivalents of oxygen per kilogram, while control experiments kept in the dark, lacking hemoglobin, or starved of oxygen showed only trace oxidation. The conclusion was unambiguous: hemoglobin, oxygen, and light must all be present simultaneously for the reaction to proceed efficiently. Under true sunlight, the peroxide value reached an even higher 10.5, confirming that the laboratory simulator faithfully reproduces the outdoor process. Spectroscopic monitoring of the heme’s characteristic Soret absorption band at 407 nanometers revealed a 69.8 percent decline over extended irradiation, evidence that the photosensitizer itself is progressively degraded as it works.

To dissect the mechanism, the researchers deployed chemical scavengers as molecular interrogators. Adding butylated hydroxytoluene, a potent free-radical quencher, cut the peroxide value to 3.8, implicating carbon-centered radicals generated by hydrogen abstraction. Adding sodium azide, a classic singlet oxygen scavenger, suppressed oxidation even further, to 3.1, demonstrating that singlet oxygen, an excited and highly reactive form of molecular oxygen, is a major player. Both pathways operate at once, which helps explain why hemoglobin outperformed two benchmark oxidants: the dye Rose Bengal, a selective singlet oxygen generator that achieved a peroxide value of only 6.8, and potassium permanganate, a classical chemical oxidant that managed just 2.1 under comparable conditions.

Proton nuclear magnetic resonance spectroscopy provided product-level confirmation of the damage. Signals from vinylic protons on the oil’s carbon-carbon double bonds, at chemical shifts of 5.2 to 5.4 parts per million, fell by 31.2 percent, consistent with singlet oxygen attacking double bonds through ene reactions. Bis-allylic protons, at 2.7 to 2.8 parts per million, declined even more sharply, by 36.9 percent, a signature of radical-mediated hydrogen abstraction at the most vulnerable positions of polyunsaturated fatty acids. A new aldehydic resonance near 9.5 parts per million announced the formation of MDA, the definitive marker of advanced peroxidation and chain scission. Perturbations in the glycerol proton region around 4.1 parts per million suggested that radical-driven beta-scission was even cleaving the ester bonds of the triglyceride backbone, fragmenting the oil into smaller, more polar molecules.

An independent probe sealed the case for singlet oxygen. Anthracene, a compound that reacts selectively with singlet oxygen to form a colorless endoperoxide, lost roughly 33 percent of its absorbance at 375 nanometers after four hours of irradiation in the hemoglobin-oil system, and sodium azide largely halted the bleaching. The solvent experiments added a subtle layer of physical chemistry: oxidation efficiency followed the order acetonitrile, ethanol, acetone, methanol, then dimethyl sulfoxide, mirroring the known lifetimes of singlet oxygen in these media, which range from about 65 microseconds in acetonitrile down to 19 microseconds in DMSO. Highly coordinating solvents like DMSO may also interfere with the formation of ferryl heme intermediates, the high-valent iron-oxo species suspected of driving the radical pathway.

That ferryl pathway remains the tentative half of the mechanism. The authors are careful to note that they did not directly observe the ferryl species, hemoglobin iron in the +4 oxidation state bound to oxygen. Its involvement is inferred from indirect evidence: the suppressive effect of the radical scavenger BHT, the preferential depletion of bis-allylic protons, and the damping effect of DMSO. Previous work on related metalloporphyrin and hemoglobin systems has detected ferryl intermediates spectroscopically, lending plausibility to the interpretation, but direct confirmation in this food system awaits future study. Even so, the combined evidence supports a dual oxidative engine: singlet oxygen generated by energy transfer from the light-excited heme, working in parallel with a heme-iron radical chemistry that abstracts hydrogen from the lipid chains.

The implications stretch well beyond the shelf life of bottled oil. Hemoglobin is abundant, biodegradable, and essentially free, recovered as a by-product of meat processing that would otherwise be discarded. The study’s preliminary results suggest that this waste protein could be harnessed as a low-cost photosensitizer for sunlight-driven degradation of lipid-rich effluents from edible oil processing, replacing ozonation and Fenton treatments that demand harsh chemical oxidants and energy-intensive conditions. The authors caution that real industrial wastewater, long-term protein stability under continuous illumination, light penetration, oxygen transfer, and reactor scale-up all remain to be tested. Still, the vision is compelling: a circular food system in which blood from the slaughterhouse becomes a solar-powered catalyst for cleaning the oil industry’s dirtiest water, while simultaneously teaching food scientists exactly how to keep light and heme apart to protect the products on our shelves.

Subject of Research: Hemoglobin-mediated sunlight-induced lipid oxidation in edible oils and its potential for sustainable wastewater treatment

Article Title: Sunlight‐Induced Lipid Oxidation and Degradation of Edible Oil Mediated by Hemoglobin: Implications for Food System Sustainability

Article References: Hajimohammadi, M., Faraj, F. H., Boghdachi, M., Alwasiti, A. A., & Shnain, Z. Y. (2026). Sunlight‐Induced Lipid Oxidation and Degradation of Edible Oil Mediated by Hemoglobin: Implications for Food System Sustainability. Food Science & Nutrition, 14(10), Article e72423. https://doi.org/10.1002/fsn3.72423

Image Credits: AI Generated

DOI: 10.1002/fsn3.72423

Keywords: hemoglobin, lipid oxidation, singlet oxygen, edible oil, photosensitizer, photooxidation, malondialdehyde, ferryl heme, food science, wastewater treatment, circular economy, sunlight

The trial involved 300 one-day-old male Cobb 500 broiler chicks, randomly assigned to five dietary treatments with four replicate pens of 15 birds each. One group received a standard corn–soybean meal control diet, while the others were fed diets supplemented with either 0.75 percent or 1.5 percent Prangos ferulacea powder, or with 750 or 1500 milligrams per kilogram of the plant’s aqueous extract. All diets were formulated to be isocaloric and isonitrogenous, meaning they delivered equivalent levels of energy and protein, so any differences between groups could be attributed to the plant material itself rather than to nutritional imbalances. The birds were monitored over a full 43-day production cycle spanning starter, grower, and finisher phases.

The plant material itself carried considerable biochemical promise. Prangos ferulacea is native to West Asia and is rich in monoterpenes, coumarins, and phenolic compounds — classes of molecules frequently associated with antioxidant, antimicrobial, and smooth-muscle-modulating activity. The researchers harvested mature aerial parts of the plant from the rangelands of Divandareh County in Kurdistan Province, shade-dried them, and milled them into powder. To prepare the aqueous extract, ten kilograms of powder were macerated in thirty liters of distilled water for twenty-four hours, filtered, and concentrated at sixty to seventy degrees Celsius, yielding roughly 10.8 percent of the starting weight as dried extract. Botanical identity was confirmed by a qualified botanist, and a voucher specimen was deposited in the university herbarium, lending the study a level of taxonomic rigor that is not always present in phytogenic feed research.

When it came to the bottom line of broiler production — body weight gain and feed conversion ratio — the results were sobering. Across the entire 43-day period, cumulative body weight gain and feed efficiency did not differ significantly among the five dietary groups. Body weights at eleven, twenty-three, and forty-three days of age were statistically indistinguishable. There was, however, a phase-specific wrinkle: during the finisher period from days twenty-four to forty-three, body weight gain was significantly reduced in the supplemented groups compared with the control, a pattern the authors suggest could relate to effects on feed intake or palatability, though the underlying cause was not directly measured. Feed intake during the grower phase was actually higher in all supplemented groups, yet this did not translate into better growth, and overall feed intake across the trial was unaffected.

Carcass characteristics told a similarly restrained story. Carcass yield and the relative weights of the heart, liver, spleen, pancreas, and bursa of Fabricius were comparable across treatments. One exception stood out: birds fed the lower dose of the powder, 0.75 percent of the diet, showed a significantly heavier gizzard relative to their body weight than both extract-fed groups and the control. The authors speculate that the fibrous, structural nature of the powdered plant material may have stimulated gizzard development, a phenomenon previously reported with coarse or fiber-rich feed components, but they caution that because particle size was not measured, this interpretation remains speculative.

Blood chemistry offered a few more points of interest. Serum triglycerides were significantly lower in birds receiving 0.75 percent powder, while very-low-density lipoprotein levels were unchanged, suggesting the plant does not exert a broad effect on lipid metabolism. Serum cholesterol was significantly lower in birds receiving both forms of supplementation compared with controls, and markers of kidney function — urea, creatinine, and uric acid — were unaffected, indicating the treatments were not harming the birds. Total protein, albumin, and globulin concentrations also remained stable, painting a picture of animals whose basic metabolic health was intact regardless of diet.

The most intriguing and, frankly, most puzzling findings emerged from the antioxidant measurements. Birds receiving the highest dose of aqueous extract, 1500 milligrams per kilogram, showed a significant increase in serum total antioxidant capacity, a measure of the blood’s non-enzymatic antioxidant potential. That might sound like a win for the plant. But the same group also exhibited significantly elevated serum malondialdehyde, a well-established marker of lipid peroxidation and oxidative damage, alongside significantly reduced glutathione peroxidase activity in the liver, one of the body’s key antioxidant enzymes. In fact, all four supplemented groups showed reduced hepatic glutathione peroxidase activity compared with controls, while liver superoxide dismutase showed only a trend toward reduction and red blood cell enzyme activities were unchanged.

This pattern — higher total antioxidant capacity coexisting with more lipid damage and less enzymatic defense — does not add up to an unequivocal antioxidant benefit, and the authors are careful to say so. Rather, they argue, it points to a complex and potentially pro-oxidant response at the highest extract dose, consistent with the dose-dependent or biphasic effects that phytochemicals sometimes display. It also underscores a broader lesson for the field: antioxidant biomarkers should be interpreted collectively rather than in isolation, and a shift in any single indicator does not necessarily signal improved health. Notably, none of the biochemical changes translated into better growth, feed efficiency, or carcass yield, reinforcing a growing consensus that modulating redox biomarkers under low-stress conditions may not produce tangible production benefits.

The study has honest limitations that shape how its findings should be read. With only four replicate pens per treatment and one bird per pen sampled for biochemical analyses, statistical power to detect subtle effects was limited. The experimental diets were formulated on calculated rather than chemically analyzed nutrient values, and the phytochemical characterization relied on spectrophotometric assays of total phenolics, flavonoids, and coumarins rather than chromatographic identification of individual compounds — meaning the differences between powder and extract cannot be tied to specific active constituents or their bioavailability. The authors also note that under the non-stressed conditions of a well-managed research facility, the birds’ endogenous antioxidant systems may already have been operating near optimal levels, leaving little room for a phytogenic additive to demonstrate measurable gains.

Where does this leave Prangos ferulacea on the crowded shelf of candidate antibiotic alternatives? The study contributes to mounting evidence that phytogenic feed additives can shift oxidative status without necessarily improving performance, particularly in animals that are not under environmental or metabolic stress. The authors chart a clear path forward: comprehensive phytochemical profiling of the plant, formal dose–response studies, investigation of molecular mechanisms such as redox-sensitive signaling pathways like Nrf2, and — perhaps most importantly — testing under oxidative-stress challenge models that better mirror the realities of commercial poultry production. Until then, the mountain herb remains a biochemical curiosity with demonstrated biological activity but, at the doses and conditions tested, no proven ticket to faster-growing, healthier chickens. For an industry under pressure to eliminate antibiotics, that distinction between biochemical activity and production benefit is exactly the kind of hard evidence that keeps the search honest.

Subject of Research: Effects of dietary Prangos ferulacea powder and aqueous extract on growth performance, carcass traits, and antioxidant status in broiler chickens

Article Title: Effects of different levels of Prangos ferulacea (L.) Lindl. (Apiaceae) powder and extract on performance, carcass characteristics, and antioxidant status in broiler chickens

Article References: Janfadah, A., Sadeghi, A. A., & Karimi, A. (2026). Effects of different levels of Prangos ferulacea (L.) Lindl. (Apiaceae) powder and extract on performance, carcass characteristics, and antioxidant status in broiler chickens. Discover Animals, 3(1), Article 98. https://doi.org/10.1007/s44338-026-00250-7

Image Credits: AI Generated

DOI: 10.1007/s44338-026-00250-7

Keywords: Prangos ferulacea, broiler chickens, phytogenic feed additives, antioxidant status, total antioxidant capacity, malondialdehyde, glutathione peroxidase, feed conversion ratio, carcass characteristics, poultry nutrition, antibiotic alternatives, oxidative stress

The research team, led by Chairat Techavuthiporn and Hataitip Nimitkeatkai and their colleagues at universities in Thailand, focused on immature fruiting bodies of A. odoratus purchased from a local market in Phayao Province. These young specimens, measuring just two to two and a half centimeters across and weighing around seven grams, are spherical, firm, and white inside, with a smooth whitish mycelial covering on the outside. Like many wild ectomycorrhizal fungi, the species cannot be reliably cultivated; its fruiting depends on rainfall and soil moisture, so supply is seasonal and unpredictable. That scarcity, combined with a shelf life of only one to two days at ambient conditions, has long confined sales to local markets near where the mushrooms are foraged.

The vulnerability of A. odoratus is shared by mushrooms generally. Their tissues are packed with moisture, they lack the waxy cuticle that protects fruits and leaves from water loss, and their high respiration rates burn through energy reserves rapidly. Postharvest deterioration is driven largely by oxidative processes: reactive oxygen species such as hydrogen peroxide attack cell membranes, triggering lipid peroxidation, electrolyte leakage, and the enzymatic browning reactions that turn once-pristine flesh an unappetizing brown. Because senescence is fundamentally an oxidative phenomenon, the researchers reasoned that briefly starving the mushroom of oxygen might reset its metabolic clock, a strategy that has already shown promise in asparagus, pineapple, broccoli, litchi, banana, and another mushroom species, Stropharia rugosoannulata.

In the experiment, mushrooms were divided into two groups. One group was placed in sealed five-liter containers and flushed continuously with humidified pure nitrogen at 100 milliliters per minute for nine hours, until the residual oxygen concentration inside dropped below 0.05 percent. The control group received the same treatment with ambient air. Preliminary trials had shown that nine hours was the sweet spot, long enough to suppress deterioration but short enough to avoid the pitfalls of prolonged anaerobic metabolism, which can cause off-odors and tissue damage from accumulating fermentative byproducts such as ethanol and acetaldehyde. After treatment, all mushrooms were stored at 10 degrees Celsius and 80 to 85 percent relative humidity for nine days, with samples taken every three days for physical, chemical, and biochemical analysis.

The results were striking on several fronts. Weight loss, a key driver of mushroom quality decline, reached 12.72 percent in the control group by the end of storage but only 10.93 percent in the anoxia-treated mushrooms, a statistically significant difference. The interior flesh of treated mushrooms also stayed significantly lighter on days six and nine, and browning pigment measurements trended lower, consistent with the visual impression that treated specimens retained their fresh appearance longer. The authors attribute the reduced weight loss to suppressed respiratory activity and to better preservation of cellular structure, since intact plasma membranes and organelles limit the diffusion of water out of the tissue.

Beneath the surface, the treatment appeared to protect the mushroom’s cellular machinery from oxidative assault. Electrolyte leakage, a proxy for membrane damage, climbed from roughly 19 to 60 percent in control mushrooms over the storage period, while anoxia-treated samples rose more slowly, from about 12 to 49 percent. Malondialdehyde, the classic chemical fingerprint of lipid peroxidation, soared to 15.60 micromoles per liter in controls but reached only 10.20 in treated samples. Hydrogen peroxide accumulation was consistently lower under anoxia as well. Together, these indicators point to delayed membrane deterioration, which matters because membrane breakdown and enzymatic browning are tightly intertwined: once membranes fail, phenolic substrates and oxidizing enzymes mix freely, accelerating discoloration.

The enzymes themselves told a clear story. Polyphenol oxidase, or PPO, the principal culprit in mushroom browning, rose steadily in both groups but remained significantly lower in the anoxia-treated mushrooms throughout storage, with the gap widening in the later days. Peroxidase, or POD, another browning-associated enzyme that oxidizes phenolics into colored compounds in hydrogen peroxide-dependent reactions, followed the same pattern. The authors suggest two mechanisms: PPO requires molecular oxygen to function, so lingering oxygen scarcity after treatment constrains it, and the reduced hydrogen peroxide burden in treated tissue may have starved POD of one of its key substrates. Lower activity of both enzymes aligns neatly with the reduced browning observed visually and chemically.

Not every measured parameter responded dramatically. Total phenolic content dipped in treated mushrooms immediately after the nitrogen flush but showed no consistent differences from controls during subsequent storage, leading the authors to conclude that the treatment did not reliably preserve phenolic compounds over time. Antioxidant capacity, however, told a more encouraging story: DPPH radical scavenging activity was consistently higher in anoxia-treated samples, and ferric reducing antioxidant power trended higher as well, though the latter difference was not statistically significant. The researchers interpret this as evidence that low-oxygen exposure modulates oxidative metabolism and bolsters the mushroom’s internal antioxidant defenses rather than simply locking phenolics in place.

To tie the threads together, the team applied Pearson correlation analysis and principal component analysis to the full dataset. The correlations revealed a tight cluster linking PPO activity, brown pigment, malondialdehyde, and electrolyte leakage, confirming that enzymatic browning, lipid peroxidation, and membrane disruption proceed hand in hand. Respiration rate, measured as carbon dioxide production, was negatively associated with that cluster, indicating that lower metabolic intensity accompanied delayed browning and better membrane stability. The first principal component, explaining 65.5 percent of the variance, captured this quality deterioration axis, while the second, at 12.9 percent, was dominated by total phenolic content, suggesting phenolics contribute mainly to antioxidant buffering rather than directly controlling browning. In the score plot, anoxia-treated samples separated cleanly from controls in later storage, sitting closer to the low-metabolism, high-antioxidant end of the spectrum.

The practical implications are considerable. The treatment requires nothing more than nitrogen gas, a sealed container, and modest refrigeration, making it a low-cost, non-chemical pre-treatment that could be deployed at collection points or regional packing facilities before distribution. Because A. odoratus already fetches premium prices, even modest extensions of marketable life could meaningfully expand the economic reach of foragers and traders in rural Thailand. The authors caution that anoxic conditions must be tailored to each commodity, since excessive anaerobic exposure risks fermentative spoilage, and they note that fermentative metabolites were not directly measured in this study, leaving some biochemical questions open. Still, the findings extend a growing body of evidence that brief, controlled oxygen deprivation is a versatile and environmentally friendly tool for postharvest preservation, and they offer, for the first time, a scientifically grounded way to keep one of Southeast Asia’s most beloved wild mushrooms looking as good as the day it emerged from the forest floor.

Subject of Research: Short-term anoxic treatment to extend the postharvest shelf life of the wild edible mushroom Astraeus odoratus

Article Title: Short-term anoxia improves postharvest quality and reduces browning-related enzyme activity in edible Astraeus odoratus mushroom

Article References: Techavuthiporn, C., Jarerat, A., Julian, H., & Nimitkeatkai, H. (2026). Short-term anoxia improves postharvest quality and reduces browning-related enzyme activity in edible Astraeus odoratus mushroom. Food Chemistry: X, 39, Article 104519. https://doi.org/10.1016/j.fochx.2026.104519

Image Credits: AI Generated

DOI: Not provided

Keywords: Astraeus odoratus, postharvest quality, short-term anoxia, browning, polyphenol oxidase, peroxidase, antioxidant activity, malondialdehyde, electrolyte leakage, wild edible mushrooms, nitrogen treatment, shelf life