Psoriasis is far more than a cosmetic nuisance. It affects roughly two percent of people in Europe and North America and arises from a self-reinforcing conversation between immune cells and keratinocytes, the workhorse cells that form the epidermis. In the prevailing model, dendritic cells activate T cells that flood the skin with interleukin-17 and interleukin-22, driving keratinocytes into hyperproliferation and stabilizing thick, scaly plaques. Modern biologics that block the IL-23/IL-17 axis can transform outcomes, but they are injectable, costly, and reserved for moderate-to-severe disease. Meanwhile, oxidative stress is increasingly recognized as an amplifier of the disease loop: reactive oxygen species promote DNA damage and switch on pro-inflammatory signaling cascades such as NF-κB, MAPK, and JAK/STAT in epidermal cells. The burden is enormous—inflammatory skin diseases as a group generated an estimated 4.86 billion incident cases and 42.9 million disability-adjusted life years in 2019, prompting the WHO Executive Board in 2025 to declare skin diseases a global public-health priority. Plant-derived (poly)phenols—quercetin, resveratrol, curcumin, green tea catechins—have long shown multi-targeted antioxidant and immunomodulatory potential in preclinical models, but poor bioavailability and formulation headaches have kept most of them at the margins of dermatology.

The new work began with a formulation problem rather than a molecule discovery. Years earlier, the same research group had characterized Aliophen®, a patented extract rich in natural (poly)phenols derived from malts and hops, and showed that it could inhibit the oxidation of low-density lipoprotein and protect red blood cells from hemolysis. But the formulation carried a hidden weakness: its total (poly)phenol content was only about 0.3 percent by weight, because sugars, proteins, and other non-phenolic co-extractives bulked up the mass and diluted the bioactive punch per gram. The team hypothesized that stripping away these passengers would concentrate the activity. They first precipitated proteins with trichloroacetic acid, then passed the material through reversed-phase solid-phase extraction cartridges and eluted it stepwise with a water–acetonitrile gradient. The fraction released at 35 percent acetonitrile—Aliophen-XP—proved the most biologically active. Chemical assays confirmed the strategy had worked: total (poly)phenols jumped roughly twelvefold, from 3.23 to 36.30 milligrams of quercetin equivalents per gram of dry weight, and ferric-reducing antioxidant power rose in parallel, from 6.73 to 81.92 milligrams of Fe2+ equivalents per gram.

What exactly is inside Aliophen-XP? To find out, the researchers deployed high-performance liquid chromatography coupled to ultraviolet and fluorescence detectors and to an electrospray-ionization quadrupole time-of-flight tandem mass spectrometer, then added a nanoflow HPLC-Orbitrap pass to catch low-abundance peptides. The chemical portrait that emerged was dominated not by hop flavonoids but by barley phenolamides—above all hordatines A, B, and C, dehydrodimeric compounds assembled from hydroxycinnamic acids and agmatine—alongside a remarkable diversity of their mono-, di-, and tri-hexosylated and hydroxylated derivatives. Their monomeric precursors, p-coumaroylagmatine and feruloylagmatine, appeared at high intensity, as did free hydroxycinnamic acids such as ferulic, p-coumaric, and sinapic acid. The team also catalogued flavonoid C-glycosides including schaftoside and isovitexin-O-hexoside (meloside A), spermidine-based phenolamides, and numerous peptides derived from barley B-hordeins and serpin Z4, the likely handiwork of endogenous proteases activated during malting. Strikingly, the fraction contained no detectable xanthohumol, the much-studied prenylated chalcone of hops. That absence matters analytically: it rules xanthohumol out as the active principle and points the finger squarely at barley-derived hordatines and related phenolamides as the probable engines of the extract’s effects.

The cellular experiments were built around HaCaT cells, a spontaneously immortalized human keratinocyte line that preserves the proliferation, differentiation, and inflammatory responses of primary skin cells. First came safety: across 24- and 48-hour exposures at concentrations up to 0.8 milligrams per milliliter, viability measured by crystal violet staining stayed essentially at control levels, with a maximum dip of only about 14 percent. Then came the oxidative stress test. Cells were pre-incubated with Aliophen-XP for 30 minutes, washed thoroughly, loaded with the oxidation-sensitive fluorescent probe DCFH-DA, and finally challenged with tert-butyl hydroperoxide. The washout design is analytically crucial: because the extract was gone before the probe and the oxidant were introduced, direct chemical quenching of the fluorescent signal by the extract itself is unlikely to explain the result. Even so, fluorescence—readout of intracellular oxidant activity—was significantly lower at every tested concentration, and the protection persisted from 30 to 120 minutes after the oxidant hit, suggesting the cells had been genuinely primed rather than merely buffered.

The anti-inflammatory results followed. Keratinocytes pretreated with Aliophen-XP at 0.4 milligrams per milliliter for two hours were stimulated with tumor necrosis factor-alpha, a cytokine central to psoriatic inflammation. Quantitative RT-PCR revealed a marked, concentration-dependent dampening of the messenger RNA for IL-1β, IL-6, and IL-8—three workhorse inflammatory genes of the epidermis—and immunoblotting confirmed that IL-6 protein accumulation fell in step. The extract also raised levels of NQO1, a multifunctional flavoprotein that detoxifies quinones and supports cellular redox control, in a concentration-dependent manner. The authors are careful about interpretation: NQO1 is often treated as a textbook target of the NRF2 transcription factor, but its promoter is a regulatory crossroads where the antioxidant response element, AP-1 sites, and aryl hydrocarbon receptor signaling intersect. NQO1 induction, they write, is solid evidence of reinforced cytoprotective defenses, but not yet proof of NRF2 activation—a question that will need nuclear-translocation assays, reporter constructs, and gene-silencing experiments to settle.

The decisive test came in living animals. The team used the imiquimod model, in which a TLR7/8-activating drug applied to the skin triggers a psoriasis-like dermatitis through the same IL-23/IL-17 axis that drives the human disease. Male C57BL/6J mice had imiquimod cream smeared on one ear for four consecutive days; 30 minutes before each application, researchers painted on Aliophen-XP at 0.8 or 1.6 milligrams per milliliter. Lesions, scored daily with a modified Psoriasis Area and Severity Index combining erythema, scaling, and thickening, typically peaked on day five. At the higher dose, the extract delayed the onset of lesions and significantly blunted that peak severity; at both doses it prevented the splenic enlargement that imiquimod provokes, a sign of systemic inflammatory spread. Most telling, enzyme-linked immunosorbent assays of inflamed ear tissue showed reduced IL-17A—the signature cytokine of psoriatic pathology—hinting that topical pretreatment had functionally dented the very immune circuit that sustains plaques.

The star molecules here have a curious history. Hordatines are inducible phytoalexins—antimicrobial compounds that barley seedlings deploy against fungal attackers such as Fusarium and Blumeria graminis—and they double as radical scavengers and metal chelators. Yet their behavior in mammals remains largely uncharted, making this one of the first demonstrations that a hordatine-rich botanical fraction can attenuate psoriasiform inflammation. The formulation science underlying the result may prove as consequential as the biology: by raising phenolic content twelvefold, the enrichment step turned a dilute extract into a workable topical candidate. There is already a human signal downstream: in a separate exploratory 56-day study cited by the authors, a cream containing 4 percent of the parent Aliophen® formulation was well tolerated and improved objective measures of wrinkles, pigmentation, skin biomechanical properties, and dermal density. An adjunctive, barrier-friendly product that could be layered onto maintenance therapy for psoriasis—or for stressed, inflamed skin generally—is the obvious development direction.

The researchers are equally clear about what the study does not show. Treatment was strictly preventive, applied before lesions developed, so therapeutic value against established plaques remains untested. No pharmacological positive control—no corticosteroid or calcineurin inhibitor—was run alongside, leaving the extract’s relative potency unknown. Only IL-17A was quantified in tissue; there was no histopathology, no multiplex cytokine profiling, and no cell-type-resolved immunophenotyping of the γδ T cells, innate lymphoid cells, and dendritic cells thought to orchestrate the response. And while the washout design strengthens the antioxidant interpretation, DCFH-DA remains an indirect, non-specific probe. The necessary-and-sufficient chemistry is also unresolved: targeted fractionation of hordatines, phenolamides, and minor flavonoids will be needed to untangle synergy from redundancy. Still, the convergence of rigorous mass-spectrometric chemistry, keratinocyte biology, and disease-modifying activity in mice is an unusually complete preclinical package for a botanical fraction. By simultaneously raising the redox threshold and quieting inflammatory transcription, Aliophen-XP offers a plausible way to disrupt the feed-forward loop that keeps psoriatic skin inflamed—and it does so with molecules sourced from what might otherwise be beer’s footnote ingredients.

The scientific community has historically approached Nymphaea spp. with a fragmented lens, resulting in sporadic findings and an absence of robust comparative analyses. This fragmentation critically limits the translational advancement of Nymphaea constituents from raw botanical extracts to efficacious cosmetic agents. Particularly, the lack of standardized cross-method evaluations of extraction technologies hinders the identification of optimal processes that maximize yield and preserve bioactivity. Furthermore, the intricate correlations between the phytochemical profiles of Nymphaea extracts and their corresponding pharmacodynamic effects in skin care remain inadequately elucidated, obfuscating targeted ingredient development.

A recent comprehensive systematic review, published in the Journal of Dermatologic Science and Cosmetic Technology, seeks to bridge these knowledge gaps by instituting a cohesive “constituent-target-mechanism-efficacy-application” framework. This translational schema meticulously deciphers the complex sequence from compound isolation to biological function and ultimately to cosmetic application, thereby fostering a holistic understanding of Nymphaea’s dermatological potential. The review rigorously assesses contemporary extraction and purification methodologies, evaluating parameters such as solvent polarity, temperature control, and green chemistry practices to propose fit-for-purpose techniques tailored for specific bioactive targets.

Critical phytoconstituents identified within Nymphaea spp. include phenolic compounds, flavonoids, alkaloids, and polysaccharides, each exhibiting distinct mechanisms of action upon cutaneous tissues. Phenolics and flavonoids primarily confer antioxidant properties, mitigating oxidative stress that accelerates skin aging by neutralizing reactive oxygen species (ROS). Alkaloids contribute antimicrobial and anti-inflammatory effects, essential for managing acne-prone and sensitive skin types. Polysaccharides demonstrate potent moisturizing and barrier-enhancing capacities, fostering skin hydration and structural integrity. Together, these multi-target effects underscore Nymphaea’s holistic utility in skincare formulations addressing aging, inflammation, and barrier dysfunction.

From an extraction technology perspective, the review compares conventional solvent extraction with innovative green methodologies such as supercritical fluid extraction (SFE), ultrasound-assisted extraction (UAE), and microwave-assisted extraction (MAE). SFE, leveraging supercritical CO₂ as a solvent, offers superior selectivity and environmental compatibility, minimizing solvent residue and thermal degradation of heat-sensitive constituents. UAE and MAE enhance mass transfer rates and extraction efficiency by disrupting plant matrices through acoustic cavitation and microwave-induced heating, respectively. Each technique’s operational parameters are meticulously calibrated to align with the physicochemical nature of Nymphaea’s bioactives, ensuring optimal yield without compromising compound integrity.

The pharmacokinetic and pharmacodynamic profiles of Nymphaea extracts are further scrutinized, particularly in relation to skin absorption, bioavailability, and molecular target engagement. The review elucidates signaling pathways modulated by Nymphaea phytochemicals, including inhibition of matrix metalloproteinases (MMPs) involved in collagen degradation and activation of nuclear factor erythroid 2-related factor 2 (Nrf2) pathways promoting endogenous antioxidant defenses. Such mechanistic insights provide a scientific basis for claims of wrinkle reduction, skin brightening, and anti-inflammatory efficacy, substantiating Nymphaea’s position as a multifunctional botanical ingredient.

Safety and toxicological evaluations comprise another pivotal dimension of this systematic review, addressing the industry’s imperative for low-toxicity natural ingredients. The authors consolidate data from in vitro cytotoxicity assays, dermal irritation studies, and allergenicity tests, affirming the safety profile of optimized Nymphaea extracts within cosmetic concentration ranges. This evidence base supports regulatory compliance and risk assessment frameworks, facilitating the confident inclusion of Nymphaea derivatives in consumer-facing skin care products.

Importantly, the review goes beyond isolation and efficacy, contextualizing Nymphaea’s cosmetic applications within sustainability and green chemistry paradigms. By advocating for environmentally benign extraction methods and resource-efficient processes, the authors respond to the growing ethical demands of both consumers and manufacturers. This alignment with eco-conscious principles enhances the commercial appeal and market competitiveness of Nymphaea-based formulations, offering a compelling narrative that resonates within the clean beauty movement.

The integration of systematic efficacy data with mechanistic understanding propels Nymphaea from folklore to the forefront of evidence-based cosmetic science. The translational framework proposed not only delineates clear pathways for ingredient development but also suggests strategic directions for future research, including clinical trials and advanced formulation studies. Additionally, leveraging this framework could inform the discovery of synergistic botanical blends, optimizing multifaceted skincare solutions.

Such a structured and comprehensive approach addresses long-standing lacunae in botanical cosmetic research, fostering innovation grounded in rigorous scientific methodology. The review’s actionable guidelines for screening high-performance, low-toxicity phytochemicals streamline R&D workflows, expediting the pipeline from plant harvest to product roll-out. In doing so, it supports a paradigm wherein natural ingredient formulation transcends anecdotal use, achieving credibility through reproducibility and mechanistic clarity.

As the cosmetic industry evolves, the imperative for substantiated natural ingredients intensifies, positioning Nymphaea spp. as a strategic asset. The synthesis offered by this recent systematic review empowers formulators with the knowledge to harness Nymphaea’s diverse bioactivities while ensuring safety and sustainability. Ultimately, Nymphaea spp. epitomize the convergence of tradition, innovation, and ecological responsibility, embodying the future trajectory of cosmetic science in a clean beauty era.

The authors behind this pivotal review, with affiliations spanning Guangzhou Eggshell Network Technology Co., Ltd. and the South China Botanical Garden at the Chinese Academy of Sciences, exemplify collaborative expertise. Their interdisciplinary approach integrates phytochemistry, dermatology, and green extraction engineering, setting a benchmark for botanical ingredient research. Their absence of reported conflicts of interest further fortifies the impartiality and integrity of their findings.

In sum, the translation of Nymphaea spp. phytoconstituents into validated cosmetic ingredients holds transformative potential. Through methodical extraction optimization, mechanistic elucidation, and rigorous safety validation, Nymphaea emerges as a blueprint for future plant-based skincare innovations. This comprehensive review not only enriches scientific discourse but also energizes the cosmetic industry’s commitment to clean, effective, and sustainable beauty solutions.

Subject of Research: Not applicable

Article Title: Cosmetic applications of Nymphaea spp.: A review of extraction techniques, functional components, and efficacy mechanisms in skincare

Web References: http://dx.doi.org/10.1016/j.jdsct.2026.100152

Image Credits: Yongli Huo, Fangfang Duan, et al.

Keywords

Chemistry, Botanical Extracts, Cosmetic Science, Skincare Mechanisms, Green Extraction Technologies, Phytochemistry, Antioxidants, Natural Ingredients, Dermatology, Clean Beauty, Sustainable Formulation