Plant waste enzymes and nanozymes team up to break down pesticides

A new review published in the journal Biotechnology for Sustainable Materials maps out how enzymes harvested from agricultural waste could be paired with artificial enzyme mimics called nanozymes to destroy persistent pesticides in water and soil. The paper, authored by Dravin Pratap Singh, Prem Kumar, Ekta Chauhan and Eepsita Priyadarshini and published on 6 October 2026, is a review of existing literature rather than a report of new laboratory experiments, and it proposes what the authors call a green-nano roadmap for sustainable pesticide remediation built on circular bioeconomy principles.

The review focuses on two of the most widely used classes of synthetic agrochemicals: organophosphates and neonicotinoids. According to the authors, organophosphates account for roughly 40 percent of the global pesticide market, and they act by irreversibly binding to the enzyme acetylcholinesterase, causing acetylcholine to accumulate and triggering sustained neural depolarization in target organisms. The review cites estimates that less than 10 percent of the applied volume of such agrochemicals reaches the target organism, while 80 to 90 percent disperses into the environment, where it can affect air quality, adhere to soil and clay particles, or seep into groundwater aquifers.

A substantial portion of the review is devoted to the trans-generational health concerns that motivate the search for better remediation technologies. The authors draw on toxicology studies in large human populations and in mammals indicating that exposure to certain endocrine-disrupting agrochemicals during particular developmental windows can produce permanent, inheritable changes in the epigenetics of germline cells. These changes, which involve alterations in DNA methylation, histone modification and microRNA expression, occur without any change in the DNA sequence itself. The review notes that epigenetic modifications caused by pesticides have been tracked across as many as 15 to 20 generations in certain laboratory animal models, in which maternal exposure was associated with inherited diseases in offspring, including kidney dysfunction, prostate disease, impaired sperm production and loss of reproductive capability. The authors also cite epidemiological studies in humans reporting that maternal pesticide exposure can affect reproductive hormone levels in grown children, with some findings including elevated Sex Hormone-Binding Globulin, increased occurrences of chemo-resistant conditions in certain molecular subtypes of breast cancer, and elevated endometriosis risk among occupationally exposed populations.

Conventional remediation approaches, the review argues, fall short of what is needed. Techniques such as advanced oxidation processes, activated carbon adsorption and high-temperature incineration are limited by high energy consumption, the continuous formation of highly toxic secondary chemical compounds, and poor effectiveness at removing trace-level pollutants over large areas. This is the backdrop against which the authors position bio-nano hybrid technology, which combines the high catalytic specificity of naturally derived bioenzymes with the stability and tunability of nanomaterials.

The first half of the proposed pairing comes from plant waste. The review describes how microbial fermentation of citrus peelings, vegetable waste and other high-volume agricultural residues can yield a reliable supply of biocatalysts. Global citrus production exceeds 102.6 million metric tons per year, and industrial juice extraction uses roughly 40 percent of all available citrus fruit, leaving peelings, seeds, fiber-rich pulp and pomace that constitute 55 to 60 percent of the fruit’s weight. This waste stream is rich in glucose, fructose, sucrose, pectin, cellulose and limonene, making it an inexpensive substrate for microbial cultivation. Through solid-state and submerged fermentation, optimized with water activity maintained between 0.6 and 0.8 and temperatures between 30 and 45 degrees Celsius, producers can obtain cellulases, lipases and peroxidases. Untreated citrus residues also induce ligninolytic fungi such as Pleurotus pulmonarius and Trametes hirsuta to secrete ligninases, manganese peroxidases and laccases, enzymes capable of breaking down the recalcitrant aromatic rings found in resistant pesticide formulations.

The second half of the pairing is the nanozyme: a nanomaterial with enzyme-like catalytic activity. The review catalogs three well-characterized activity types documented since 2018. Peroxidase-mimicking nanozymes, including iron, gold, cobalt and vanadium pentoxide nanowires and bimetallic nanostructures, use hydrogen peroxide to oxidize substrates. Oxidase-like nanozymes, exemplified by cerium oxide and platinum nanoparticles, catalyze oxidation using dissolved molecular oxygen without added peroxide. Catalase-mimicking nanozymes, with cerium oxide as the archetypal system, decompose hydrogen peroxide into water and oxygen, toggling between functions depending on the Ce3+/Ce4+ surface ratio. The review highlights the durability of these materials: iron oxide nanoparticles with peroxidase-like activity remained stable across temperatures from 4 to 80 degrees Celsius with only marginal variation in catalytic rate, platinum nanoparticles retained activity after autoclaving at 121 degrees Celsius, and nanozymes show a storage stability of around 12 months compared with a 4 to 8 week shelf life for natural enzymes.

The core of the roadmap is the synergistic cascade. Free bioenzymes are highly selective and can rapidly cleave complex pesticide molecules, but they do not always completely mineralize small aliphatic chains or aromatic rings, leaving toxic by-products behind. Metallic nanozymes generate intense reactive oxygen species but cannot target specific substrates, wasting oxidative capacity on non-target organic matter. In a hybrid system confined within a shared protective matrix, the bioenzyme first performs a specific deconstruction of the parent pesticide, rendering it toxicologically inactive and structurally unstable, and the nanozyme then attacks the resulting intermediates with ROS, driving them toward mineralization into carbon dioxide, water and inorganic phosphates. The review illustrates this with two case studies. In chlorpyrifos degradation, bacterial bioenzymes such as those from Bacillus cereus AKAD 3-1 cleave the phosphorothioate ester bond, producing the persistent intermediates 3,5,6-trichloro pyridin-2-ol and O,O-diethyl O-hydrogen phosphorothioate; a cerium-based metal-organic framework nanocatalyst then oxidizes these intermediates immediately, preventing accumulation. In glyphosate degradation, bio-catalyzed cleavage of the carbon-nitrogen bond yields 2-(methylamino) acetic acid and amino-oxyphosphonic acid, which transition-metal nanozymes then oxidize so that no toxic phosphorus-containing side products remain. The authors report that hybrid chlorpyrifos elimination models optimized with artificial neural networks and response surface methodology have achieved R² values exceeding 0.99.

Practical deployment is envisioned through bio-hydrogel filtration platforms. The review describes hydrogels built from chitosan and carboxymethyl cellulose, saturated with gold-palladium nanozymes synthesized on porous diatomite and immobilized organophosphate hydrolase enzymes. In this architecture, the organophosphate hydrolase converts methyl parathion into p-nitrophenol, which the Au-Pd nanozyme cascade then mineralizes. The review also reports a pilot-scale example: modular bio-hydrogel cartridges deployed at flow rates of 50 liters per hour in decentralized agricultural wastewater treatment achieved more than 95 percent initial degradation of chlorpyrifos, though field operation revealed severe biofouling from dissolved natural organic matter competing for adsorption sites, requiring periodic alkaline backwashing to regenerate the active sites. Sensing is integrated into the same framework. Nanozyme-based biosensors, including acetylcholinesterase inhibition assays and colorimetric and electrochemical platforms, have reported detection limits ranging from 0.1 to 10 nanograms per milliliter for standard colorimetric assays down to below 0.001 nanograms per milliliter for advanced photoelectrochemical and molecularly imprinted hybrid systems, and paper-based microfluidic devices with Fe3O4/Au nanozymes have detected three organophosphate pesticides in tomato and pepper extracts at limits of detection between 0.005 and 0.05 nanograms per milliliter.

The review is candid about the obstacles between laboratory promise and field reality. Scaling green phyto-fabrication from batch to continuous industrial processing is complicated by geographic and climatic variability in plant extract chemistry, which can alter nanoparticle size, crystalline shape and catalytic activity. Enzyme robustness under field conditions involving temperature swings, ultraviolet radiation and varying soil alkalinity still requires improvement, and the authors point to directed evolution and computational protein engineering as possible solutions. Nanoparticle leaching into soil remains an unresolved environmental risk, and the authors call for extensive ecotoxicity profiling and rigorous life cycle assessments before commercial deployment. On the regulatory side, the paper discusses the REACH regulation’s proposed category of persistent, mobile and toxic compounds, the ZeroPM initiative, and OECD Test Guideline 318 for nanomaterial dispersal stability, warning against what the authors term regrettable remediation, in which a remediation technology itself releases dangerous heavy metals from unstable nanozymes or converts one hazardous pesticide into an even more toxic metabolite.

The authors also state the scope limitations of their proposed framework explicitly: at present it applies to aqueous-phase applications and point-of-use water filtering for agriculture, and extending bio-hydrogels into soil dynamics, where phosphates and neonicotinoids can be strongly sequestered, remains an important area for future study. They identify priorities including artificial-intelligence-assisted protein engineering, self-healing nanozymes with defect-filled surface doping, multi-enzyme cascade systems, continuous-flow bioreactors, and techno-economic and life cycle assessment of industrial scalability. As a forward-looking synthesis rather than a demonstration of a finished technology, the review’s central message is that agricultural residues could simultaneously supply the enzymes, the scaffolds and the nanomaterials needed to dismantle the very pesticides that farming releases into the environment, provided that stability, biodegradability and standardized performance evaluation are convincingly addressed.

Subject of Research: Synergistic use of plant-waste derived bioenzymes and nanozymes for sustainable pesticide remediation

Article Title: Synergistic integration of plant-waste derived bioenzymes and nanozymes for advanced pesticide remediation: a green-nano roadmap

Article References: Singh, D. P., Kumar, P., Chauhan, E., & Priyadarshini, E. (2026). Synergistic integration of plant-waste derived bioenzymes and nanozymes for advanced pesticide remediation: a green-nano roadmap. Biotechnology for Sustainable Materials, 3(1), Article 15. https://doi.org/10.1186/s44316-026-00066-1

Image Credits: AI Generated

DOI: 10.1186/s44316-026-00066-1

Keywords: pesticide remediation, nanozymes, bioenzymes, agricultural waste, organophosphates, chlorpyrifos, glyphosate, circular bioeconomy, bio-hydrogels, reactive oxygen species, epigenetics, biosensors