From Waste to Dermocosmetic Value: A Narrative Review of Agro-Industrial Residues in Skincare Innovation

Abstract

The environmental burden from cosmetic production has intensified interest in sustainable and scientifically robust raw materials. Among the emerging alternatives, agro-industrial residues are gaining attention as chemically rich sources of bioactive compounds with potential for dermocosmetic applications. However, research on their molecular activity, formulation performance, and industrial feasibility remains fragmented across the fields of sustainability, dermatology, and engineering. This narrative review synthesizes current knowledge on the phytochemical composition of extracts from agro-residues. It also critically examines their effects on key skin-related pathways, including oxidative stress modulation, extracellular matrix regulation, inflammation, senescence, and barrier function. Compounds such as polyphenols, carotenoids, peptides, and polysaccharides have been reported to influence signaling networks, including Nrf2/ARE, NF-κB, TGF-β/Smad, and PI3K/AKT/mTOR. Importantly, most of this evidence originates from in vitro and ex vivo studies on animal models, while controlled human and clinical studies remain limited; thus, mechanistic findings should not be equated with proven dermocosmetic efficacy. Nevertheless, challenges remain, such as compositional variability, safety-validation requirements, limited skin bioavailability and stability of bioactives in finished formulations, and limitations in scalable green extraction. Economic modeling and life-cycle assessment also highlight the need to verify both financial and environmental viability. Advancing agro-residue-derived bioactives toward mainstream cosmetic use will require strategies that integrate molecular characterization, regulatory alignment, rigorous claims substantiation and sustainable process optimization.

1. Introduction: From Waste to Functional Bioeconomy

Human activity is a major driver of climate change, biodiversity loss, and ecosystem degradation, generating environmental pressures that increasingly exceed adaptation capacities [1]. Industrial sectors characterized by high consumption patterns, including cosmetics, contribute significantly to resource depletion through intensive raw material extraction, energy demand, water consumption, and waste generation [2]. The global cosmetic market, valued at over 300 billion USD, reflects not only economic expansion but also intensified production chains and consumer usage dynamics involving multiple daily products and hundreds of raw materials [3]. This consumption model is associated with packaging waste, microplastic release, and manufacturing-related emissions, reinforcing the need for more sustainable alternatives [4].

In response, circular economy and bioeconomy frameworks have emerged as strategic models to reconcile industrial productivity with environmental stewardship [5]. Within this context, agro-industrial residues represent an underexploited yet highly promising resource. Agricultural and food processing residues include fruit peels, seeds, pomace, stems, marine biomass, and agro-polymers, are often discarded despite containing concentrated pools of bioactive compounds [6]. Their valorization addresses two interconnected challenges: reducing organic waste accumulation and decreasing reliance on non-renewable or synthetic cosmetic ingredients [6].

The integration of agro-residues into cosmetic and dermatological formulations goes beyond sustainability rhetoric. Many of these by-products are rich in polyphenols, carotenoids, flavonoids, peptides, polysaccharides, and structural biopolymers. These compounds can modulate key biological pathways involved in oxidative stress, inflammation, pigmentation, and extracellular matrix (ECM) degradation [7]. For instance, oxidative stress from reactive oxygen species (ROS) activates enzymes such as collagenase, elastase, and hyaluronidase. This contributes to extracellular matrix breakdown and premature skin aging. Agro-residue-derived bioactives have shown potential to modulate these processes in preclinical models, although formulation- and clinical-level confirmation remains limited [7,8].

Furthermore, the valorization of agricultural waste aligns with the United Nations Sustainable Development Goals, particularly Goal 9 (industry, innovation, and infrastructure) and Goal 12 (responsible consumption and production) [9] by promoting resource efficiency and waste-to-value conversion [9]. Beyond environmental benefits, this approach also offers economic advantages by reducing waste management costs and generating new high-value cosmetic ingredients from previously discarded biomass [6].

Thus, the transition from waste management to a functional bioeconomy represents not merely an ecological adjustment but a paradigm shift in cosmetic science [5]. Agro-residue-derived bioactives may link sustainability objectives with dermocosmetic functionality, supporting circular innovation as a central driver of next-generation cosmetic development. However, despite growing interest in agro-residue valorization, the literature remains fragmented. Circular bioeconomy research often focuses on waste conversion and green processing technologies, with limited attention to molecular or clinical efficacy. In contrast, dermatological studies emphasize bioactivity while frequently overlooking phytochemical variability, regulatory requirements, and industrial reproducibility [5]. Consequently, the transition from sustainable biomass to cosmetic applications with translational relevance is rarely addressed in an integrated manner.

This narrative review uniquely integrates phytochemical, mechanistic, formulation, and regulatory dimensions surrounding agro-residue valorization in cosmetology. Several earlier reviews have addressed this topic from complementary perspectives, focusing on specific raw materials (e.g., grape, olive, citrus, coffee), specific compound classes (poly-phenols, lipids, peptides), or specific processing strategies (green extraction, encapsulation).

Table 1. Representative review articles on agro-residue valorization in cosmetics and dermatology.

Scope/Focus	Main Classes of Compounds Covered	Coverage of Formulation/Clinical Aspects	Reference
Fruit industrial by-products and circular economy	Polyphenols, fibers, pectin, carotenoids	Limited; focus on valorization routes	[8]
Olive oil industry by-products in skin health	Phenolics (oleuropein, hydroxytyrosol), squalene, tocopherols	Partial; topical formulations discussed	[14]
Olive oil industry by-products for functional foods/cosmetics	Phenolics, lipids, fibers	Partial	[15]
Natural cosmetics: safety and EU legislation	Plant extracts in general	Strong on regulation; weak on mechanisms	[12,16]
Polyphenols as active ingredients in cosmetics	Polyphenols and delivery systems	Strong on penetration/formulation	[12]
Natural antioxidants in cosmeceuticals	Polyphenols, carotenoids, vitamins	Strong on extraction and aging applications	[13]
Skin microbiome: prebiotics, probiotics, postbiotics	Biotic ingredients (some derived from agro-residues)	Strong on regulation and clinical evidence	[17]

summarizes representative review articles published in the last decade, highlighting their thematic scope and identifying gaps that the present review aims to bridge [8,10,11,12,13].

Following this introduction, this narrative review is structured into four thematic sections. The first section explores the phytochemical composition of agro-industrial residues and the principal classes of bioactive molecules they contain. The second section examines the biological mechanisms through which these compounds influence skin physiology and aging-related pathways. The third section discusses the key industrial and regulatory barriers to their practical implementation, including issues of standardization, safety evaluation, and techno-economic feasibility. The final section highlights emerging research directions and technological strategies that may enable the future integration of agro-residue-derived bioactives into dermocosmetic innovation.

2. Phytochemical Composition of Agro-Residues and Their Bioactive Potential

The dermal efficacy of agro-residue-derived bioactives is ultimately determined by their chemical composition and structural features [18]. Agro-industrial residues contain structurally diverse compounds capable of modulating oxidative stress, enzymatic activity, and extracellular matrix integrity processes central to skin homeostasis and aging [7,19]. Structural motifs such as conjugated aromatic systems and phenolic hydroxyl groups confer redox reactivity, enabling electron donation and radical stabilization [7,20]. Through these mechanisms, residue-derived compounds influence oxidative signaling and matrix-degrading enzymes [7]. Among the major phytochemical families present, polyphenols stand out as particularly significant, underpinning many of the antioxidant and dermoprotective effects attributed to agro-residue extracts in cosmetic applications [21].

2.1. Polyphenols

Polyphenols represent one of the most extensively studied classes of bioactives derived from agro-residues [8,22]. Sweet cherry stems, grape pomace, citrus peels, blackcurrant skins, pomegranate residues, tomato by-products, coffee waste, and yerba mate contain flavonoids, catechins, anthocyanins, hydroxycinnamic acids, and phenylpropanoids with demonstrated dermocosmetic potential [8]. Phenolic compounds from agro-residues show promising skin-related bioactivities; however, their performance in finished formulations depends critically on extraction methods, purification strategies, and downstream handling, which influence chemical stability, concentration, and bioavailability. Variability in raw material composition and processing conditions can significantly affect phenolic profiles, thereby impacting reproducibility and functional performance in cosmetic systems [21,23].

As highlighted by Gullón et al. (2020), catechin, commonly present in agri-food by-products such as sweet cherry pomace, cocoa bean shells, apple pomace, and grape seeds, can inhibit elastase and hyaluronidase while moderately inhibiting tyrosinase activity [15]. Since elastase and hyaluronidase break down collagen and hyaluronic acid, and tyrosinase regulates melanin synthesis, the inhibition of these enzymes in in vitro enzymatic assays suggests potential protective effects against extracellular matrix degradation and hyperpigmentation [24,25].

However, no controlled human clinical data are available to confirm corresponding cosmetic outcomes for these specific by-products. Similarly, studies on berry-processing residues show that anthocyanins recovered from blackcurrant by-products exhibit strong antioxidant properties in chemical and cellular assays. They also have potential as renewable semi-permanent hair dyes, supported by laboratory-scale wash-resistance testing rather than by clinical trials [25].

Recent investigations report that their chromophoric structure, characterized by conjugated aromatic systems, enable stable color deposition with limited washout after repeated shampoo cycles, offering a promising alternative to synthetic dyes while avoiding hazardous intermediates [19,20].

Citrus by-products, especially from grapefruits, oranges, and lemons, are rich in naringenin, a flavanone with well-characterized (largely in vitro) antioxidant and photobiological activity. Its conjugated aromatic system and hydroxyl substitutions enable absorption within the UVA–UVB range and provide an electron-donating capacity that facilitates radical stabilization. In cellular models, naringenin reduces lipid peroxidation and neutralizes reactive oxygen species (ROS), including hydroxyl radicals, superoxide anions, hydrogen peroxide, and nitric oxide. By limiting oxidative damage to membrane lipids and intracellular macromolecules, it may mitigate early photochemical injury. Moreover, naringenin has been shown to enhance keratinocyte survival following UVB exposure by attenuating apoptosis associated with pyrimidine dimer formation, thereby contributing to preserving epidermal integrity under photostress [26,27]. Clinical confirmation of these in vitro effects in human skin remains limited [28].

Complementary mechanisms are observed in other agro-residue-derived compounds. Lycopene from tomato processing waste, a highly conjugated carotenoid, has been shown to quench singlet oxygen and to reduce UV-induced erythema in controlled human studies of oral supplementation [23,24], whereas evidence specifically for topical lycopene from tomato by-products is more limited [29]. Punicalagin from pomegranate peel modulates MAPK signaling and inflammatory mediators implicated in photoaging in keratinocyte models [23,30]. Together, these findings indicate that phenolics and carotenoids recovered from agro-industrial residues act at multiple levels of the photodamage cascade, targeting both oxidative and inflammatory pathways [24], although the strength of evidence varies markedly across compounds and ranges from in vitro mechanistic data to a small number of randomized clinical trials.

However, antioxidant-based photoprotection should not be equated with the photoprotective performance of regulated UV filters. Most phenolic compounds have limited UV absorption capacity compared to conventional broad spectrum sunscreen agents. Improvements in cellular oxidative markers do not necessarily lead to measurable increases in sun protection factor (SPF) or UVA protection metrics [31].

Accordingly, agro-residue-derived antioxidants primarily function as biological photoprotective modulators, helping to protect cells by influencing cellular responses to UV exposure. Unlike direct UV-blocking agents that physically absorb or reflect UV radiation, these antioxidants act by mitigating oxidative and inflammatory damage. However, due to their limited UV absorption and concentration constraints, they can not provide the same protective effectiveness as regulated sunscreen filters [31]. Robust formulation testing and clinical validation are therefore required to confirm their real-world dermocosmetic performance.

2.2. Bioactive Lipids and Fatty Acid Derivatives

Beyond phenolic compounds, agro-industrial residues also contain lipid fractions with direct structural and functional relevance to skin physiology [14]. These lipidic components, primarily triglycerides, free fatty acids, phospholipids, sterols, and lipophilic antioxidants, contribute to barrier organization, oxidative stability, and modulation of cutaneous inflammation [10]. Factors like fatty acid composition, degree of unsaturation, and minor lipophilic constituents such as tocopherols and phytosterols largely determine the biological importance of these fractions [10]. Olive pomace, a major by-product of olive oil production, retains a residual lipid fraction enriched in monounsaturated fatty acids, particularly oleic acid (C18:1), alongside linoleic acid (C18:2), palmitic acid, squalene, tocopherols, and phytosterols [15,32]. The predominance of unsaturated fatty acids confers fluidizing properties relevant to stratum corneum lipid organization, while tocopherols contribute lipophilic antioxidant capacity within the intercellular lipid matrix [10]. Most mechanistic studies on oleuropein focus on phenolic antioxidant activity; however, the lipid fraction of olive pomace itself represents a structurally relevant emollient system with potential barrier-supportive applications in dermocosmetic formulations [15].

Similarly, oil recovered from spent coffee grounds is characterized by a high content of linoleic and palmitic acids, with minor amounts of oleic acid and tocopherols [15,33]. Linoleic acid, an essential fatty acid involved in ceramide synthesis, plays a recognized role in maintaining epidermal barrier integrity and regulating transepidermal water loss [11]. Given its fatty acid profile of coffee oil presents strong potential as a barrier-supportive lipid ingredient, though confirmationin clinical context is still needed [33].

Besides olive and coffee residues, berry fruits pressing and wine industry by-products constitute important sources of fatty acids, lipophilic vitamins, and phytosterols. Cold-pressed grape seed oil, recovered from grape pomace generated by the wine industry, is dominated by polyunsaturated fatty acids (mainly linoleic acid, typically 65–75% of total), with smaller amounts of oleic, palmitic, and stearic acids [34,35]. The unsaponifiable fraction is rich in tocopherols and tocotrienols (with γ-tocotrienol and α-tocopherol as predominant isomers), β-sitosterol as the main phytosterol, and small amounts of squalene and some residual phenolics such as catechin and epicatechin [34,36]. This composition supports its use as a lightweight, low-comedogenic emollient in topical formulations and as a vehicle for lipophilic actives. A split-face, blinded, placebo-controlled clinical study by Shawahna (2022) reported that a dermo-cosmetic nanoemulgel containing grape seed oil improved several facial skin biophysical parameters (hydration, elasticity), providing one of the few human studies focused on this winery by-product [37].

Berry by-products, such as blackcurrant, raspberry, cranberry, and sea buckthorn seeds, are generated after juice or pulp pressing. These seeds retain oils enriched in essential fatty acids (α-linolenic and linoleic acids), tocopherols, carotenoids, and phytosterols [38]. The high levels of ω-3 and ω-6 fatty acids in these oils are mechanistically relevant for epidermal lipid synthesis and the modulation of cutaneous inflammation, while their tocopherol and carotenoid content provides additional oxidative stability [33,34]. These lipid fractions, therefore, complement phenolic-rich extracts from the same residues and broaden the range of structurally relevant emollients available from agro-industrial side streams.

Complementing these structural fatty acid effects, lipid-soluble carotenoids recovered from agro-aquaculture matrices, such as β-carotene and astaxanthin, provide antioxidant protection within lipid environments [39]. Their conjugated double-bond systems quench reactive oxygen species in lipid membranes efficiently, thereby reinforcing oxidative stability and supporting membrane lipid functions.

Overall, lipid fractions from agro-industrial residues show barrier-relevant features and a generally favorable safety profile. Several plant-derived fatty acid oils are already classified as safe for current uses by the Cosmetic Ingredient Review Expert Panel [40]. However, their clinical performance ultimately depends on stability, formulation design, and rigorous efficacy validation [41].

2.3. Peptides and Protein Hydrolysates

Agro-industrial residues also represent valuable protein-rich sources that can be converted into bioactive peptides and protein hydrolysates through enzymatic or chemical processing [42]. These peptides, typically characterized by low molecular weight and improved bioavailability, have attracted growing interest for their effect on skin health, including antioxidant activity, support for the ECM, and anti-inflammatory properties [43].

Protein hydrolysates from food industry by-products are particularly valuable due to their high protein content, which typically ranges from 5.5% to over 40%, depending on the source [44]. Brewer’s spent grain (BSG), the main solid by-product of beer brewing, consisting of the residual barley grain after wort extraction, for example, contains approximately 15.9–35% proteins alongside cellulose, hemicellulose, lignin, sugars, and lipids, making BSG a suitable substrate for enzymatic bioconversion [45].

Controlled enzymatic hydrolysis generates polypeptides, oligopeptides, and low-molecular-weight peptides (<3500 Da), which have been reported, mainly in in vitro studies, to exhibit improved dermal penetration compared to intact proteins. These peptides act as multifunctional bioactives capable of inhibiting skin-aging enzymes (elastase, collagenase, hyaluronidase, tyrosinase) [46], although clinical confirmation of these effects through standardized dermo-cosmetic endpoints is still scarce.

Hydrolysates from soy, rice, corn, and wheat proteins have been evaluated by regulatory bodies such as the Cosmetic Ingredient Review Expert Panel and are considered safe for cosmetic use under defined molecular weight specifications [40]. Soy-derived peptides, in particular, have demonstrated antioxidant and anti-inflammatory effects, while BSG-derived peptides have been reported to exhibit wound-healing and barrier-supportive properties in cellular and ex vivo models [47].

Enzymatic hydrolysis not only releases bioactive peptides, but it can also facilitate the recovery of phenolic acids such as ferulic and p-coumaric acid from plant residues, further enriching extract functionality [47]. The major molecular classes recovered from agro-industrial residues, together with their representative sources and reported dermocosmetic relevance, are summarized in

Table 2. Major classes of bioactive compounds recovered from agro-industrial residues and their dermocosmetic relevance.

Molecular Class	Major Compounds	Agro-Industrial Source	Biological Effects on Skin (Level of Evidence)	References
Polyphenols	Catechin, quercetin, epicatechin, anthocyanins, naringenin, hesperidin	Fruit pomace, grape residues, citrus peel	Elastase inhibition, antioxidant activity, photoprotection (in vitro and limited in vivo)	[17,18,21,48]
Carotenoids	Lycopene, β-carotene, astaxanthin	Tomato residues, aquaculture by-products	Singlet oxygen quenching, photoprotection (in vitro and human clinical for oral lycopene)	[23,35]
Peptide hydrolysates	Bioactive oligopeptides	Brewer’s spent grain (BSG), soy residues	ECM stimulation, anti-inflammatory activity (in vitro, limited clinical)	[40,44]
Polysaccharides	β-glucans, arabinoxylans	Cereal bran, BSG	Barrier support, microbiome modulation (mostly in vitro)	[49]
Lipid fractions/fatty-acid oils	Linoleic, oleic, palmitic acids; tocopherols; phytosterols; squalene	Grape seeds (winery), berry seeds, olive pomace, spent coffee grounds	Emollient/barrier support, antioxidant activity (in vitro, limited clinical)	[15,34,39,50]

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3. Functional Translation: Skin Biology and Mechanistic Effects

Having outlined the molecular diversity of agro-residue-derived compounds, their functional significance must now be considered. These compounds must be examined in relation to the biological pathways that govern cutaneous aging. The progression of skin aging reflects cumulative oxidative, inflammatory, and senescence-associated alterations. These changes are tightly regulated by interconnected signaling networks [19].

3.1. Anti-Aging and Cellular Senescence

Cutaneous aging is driven by the progressive oxidative damage, chronic low-grade inflammation, ECM degradation, and the persistence of senescent cells within dermal and epidermal compartments [48]. At the molecular level, interconnected signaling pathways orchestrate these processes. Core pathways include Nrf2/ARE, NF-κB/MAPK, TGF-β/Smad, and PI3K/AKT/mTOR [20]. Agro-industrial residues from viticulture, citrus processing, coffee production, and fruit waste contain secondary metabolites capable of modulating these pathways, thereby influencing skin aging mechanisms both structurally and functionally [51].

Beyond intracellular antioxidant signaling, several agro-industrial residues contribute to skin barrier integrity and hydration, two critical determinants of visible aging. Coffee-derived by-products, including silverskin and spent grounds, have been associated with improved barrier performance and modulation of epidermal gene expression [52]. Citrus processing residues, particularly orange and pummelo peels, provide bioactives such as hesperidin that support epidermal repair and enhance moisture retention [53]. Similarly, olive pomace extracts have been reported to increase skin elasticity and hydration while reducing transepidermal water loss (TEWL) [32]. In parallel, lipid fractions recovered from spent coffee grounds, notably those enriched in linoleic acid, contribute to reinforcement of the epidermal lipid matrix. Collectively, these findings indicate that agro-residue-derived compounds influence not only oxidative pathways but also structural and barrier-related mechanisms central to cutaneous aging [52].

Cellular senescence is marked by durable growth arrest, increased SA-β-gal activity, and secretion of pro-inflammatory senescence-associated secretory phenotype (SASP) factors. As they persist, senescent fibroblasts contribute to matrix disorganization and chronic inflammation [48].

Several agro-residue-derived compounds modulate senescence-associated pathways. Chahal et al. (2026) [54] demonstrated that fisetin, a flavonol recoverable from fruit processing residues such as strawberry and apple pomace, exhibits senolytic activity in multiple preclinical experimental systems, including cellular and animal models. It selectively induces apoptosis in senescent cells and reduces senescence markers [54]. Suppression of the PI3K/AKT/mTOR pathway has been proposed as a contributing mechanism underlying these effects; however, definitive pathway-specific validation in human dermal fibroblasts remains limited, and further mechanistic clarification is warranted [20].

Zhang et al. (2014) reported that baicalin reduces SA-β-gal-positive cells and downregulates p16, p21, and p53 expression in UVB-irradiated fibroblast (in vitro and in vivo murine models) [55]. Similarly, Lee et al. (2022) reported that galangin attenuates H₂O₂-induced senescence in human dermal fibroblasts through modulation of the SIRT1–PGC-1α/Nrf2 axis, accompanied by decreased p53, p21, and p16 levels [56].

These mechanistic findings indicate that flavonoids derived from agro-industrial residues may modulate key regulators of cellular aging and dermal homeostasis at the pathway level. Nevertheless, whether these molecular alterations result in clinically measurable dermocosmetic benefits remains uncertain. Although compounds such as fisetin and related flavonoids have demonstrated senolytic or senomorphic activity in cellular and animal models, their effects in mature human skin remain insufficiently characterized, and controlled clinical evidence supporting anti-aging outcomes is limited [57]. Moreover, senescent cell burden and responsiveness to modulators also differ by anatomical site, age, and phenotype. Additionally, pathway modulation observed in vitro does not necessarily predict effectiveness on skin without optimized delivery systems and proper dosing. Finally, extensive cutaneous metabolism of flavonoids may also reduce bioactivity unless strategies enhance skin retention and stability [57].

3.2. Photoprotection and Oxidative Stress Modulation

Beyond citrus flavanones, several agro-industrial residues yield bioactives that modulate ultraviolet-induced oxidative damage. These compounds work through complementary molecular mechanisms. Działo et al. (2016) reported that chlorogenic acid, abundant in coffee silverskin and spent grounds, attenuates UVB-induced ROS generation, while suppressing NF-κB activation and downstream matrix metalloproteinase (MMP) expression in keratinocytes (in vitro) [22]. Experimental models further suggest that chlorogenic acid activates the Nrf2/HO-1 axis, enhancing endogenous antioxidant defenses and limiting oxidative injury to cellular membranes and proteins [58].

Tomato processing residues provide lycopene, a lipophilic carotenoid with strong singlet oxygen–quenching capacity. Controlled human studies associate lycopene supplementation to reduced UV-induced erythema and decreased lipid peroxidation [59]. Lycopene acts by modulating AP-1 signaling and lowering MMP-1 expression, contributing to preserve extracellular matrix integrity when exposed to photostress [60]. Astaxanthin recovered from aquaculture by-products represents another highly conjugated carotenoid with strong membrane-protective antioxidant properties [39]. Its extended polyene structure facilitates stabilization of lipid radicals within biological membranes. Clinical investigations suggest astaxanthin supplementation can improve skin elasticity and lower photoaging biomarkers [61].

Similarly, punicalagin, derived from pomegranate peel waste, inhibits UV-mediated activation of the MAPK and COX-2 pathways while reducing oxidative DNA damage markers in keratinocyte models [30]. Ferulic acid recovered from cereal bran and brewer’s spent grain (BSG) contributes to photoprotection through dual mechanisms: partial ultraviolet absorption and stabilization of endogenous antioxidant systems. Notably, ferulic acid enhances the photostability of vitamins C and E in combined formulations, amplifying antioxidant persistence and limiting UV-induced collagen degradation [49].

The photoprotective contribution of these agro-residue-derived antioxidants differs fundamentally from that of regulated UV filters such as octocrylene, which are incorporated at substantially higher concentrations (typically 7–10%) to achieve measurable sun protection factor (SPF) values through direct photon absorption [31,62]. In contrast, phenolic acids and carotenoids are generally used at lower concentrations (often below 1%) and exert photoprotective effects primarily through attenuation of oxidative stress, modulation of redox-sensitive signaling pathways, and reinforcement of endogenous defense systems rather than through significant physical UV attenuation. Accordingly, these compounds should be conceptualized as complementary biological photoprotective agents that enhance skin resilience under photostress conditions rather than as standalone substitutes for conventional sunscreen filters [31].

3.3. Microbiome-Modulating Potential

Agro-industrial residues are increasingly being explored as microbiome-modulating ingredients within dermocosmetic innovation, particularly under circular economy frameworks. Fruit-processing by-products such as citrus peels and grape pomace provide polysaccharides and phenolic compounds that have demonstrated selective antimicrobial and anti-inflammatory effects relevant to microbial balance. Spigno et al. [63] reported, for example, that grape pomace rich in proanthocyanidins and resveratrol has been incorporated into topical formulations targeting acne-prone and sensitive skin, where in vitro studies report inhibition of Cutibacterium acnes growth and attenuation of NF-κB mediated inflammatory signaling [63].

Similarly, citrus peel-derived oligosaccharides are being investigated as prebiotic ingredients in moisturizers and barrier creams due to their potential to support commensal bacteria while reinforcing epidermal cohesion [17].

Cereal-based residues such as BSG and bran fractions have also attracted attention. BSG contains arabinoxylans, β-glucans, and phenolic acids like ferulic acid, which have been explored both for antioxidant photoprotection and for their capacity to modulate microbial ecology when applied topically. Fermented cereal extracts, often marketed as postbiotic complexes, generate organic acids and bioactive metabolites capable of lowering skin pH and influencing microbial homeostasis [49]. Coffee by-products, including silverskin and spent grounds, provide chlorogenic acid and related phenolics that exhibit antimicrobial activity against Staphylococcus aureus and may attenuate dysbiosis-associated inflammatory responses, supporting their integration into “anti-pollution” and microbiome-friendly serums [64].

A distinctive and increasingly relevant aspect of agro-residue valorization is the generation of postbiotic ingredients through microbial fermentation of plant by-products. Postbiotics, defined as non-viable microbial components or their metabolites, offer practical advantages over live probiotics in terms of stability, safety, and regulatory feasibility [37,65]. Fermented cereal and fruit extracts usually contain organic acids (e.g., lactic acid), short-chain fatty acids (SCFAs), and bioactive microbial metabolites capable of lowering skin surface pH and modulating microbial homeostasis. Mirabella et al. (2014) demonstrated that a postbiotic derived from fermented sugarcane straw (Saccharum officinarum L.), processed with Saccharomyces cerevisiae, significantly reduced the relative abundance of Cutibacterium acnes and Malassezia yeasts on human skin in a small in vivo study involving nine female volunteers, while having minimal impact on commensal species such as Staphylococcus epidermidis and Corynebacterium spp. [6]. These findings suggest that agro-residue-derived postbiotics may selectively reduce pathogenic microorganisms while preserving the commensal balance. Although, the small sample size and short study duration limit the strength of these conclusions.

More broadly, the clinical evidence base for postbiotic-based skincare is growing, although it is concentrated on commercial formulations rather than crude agro-residue extracts. A randomized split-face trial with Epidermibacterium keratini EPI-7 ferment filtrate reported increased hydration, reduced TEWL, and improved dermal density and elasticity, while enhancing microbial diversity without adverse effects [66]. A randomized split-face clinical trial demonstrated that the topical application of Epidermibacterium keratini EPI-7 ferment filtrate improved barrier function, skin elasticity, and dermal density while increasing the abundance of commensal microorganisms, providing preliminary clinical evidence for the dermocosmetic potential of postbiotic approaches [67]. A large-scale study involving 1317 participants evaluated a cream containing Aquaphilus dolomiae extract and reported high tolerability (98.5%) and user satisfaction for symptom relief, although the study relied on consumer self-assessment rather than objective biophysical measurements [68]. These clinical data illustrate the translational potential of postbiotic approaches in dermocosmetics, but also underscore that evidence specifically linking agro-residue-derived postbiotics to clinical microbiome modulation on human skin is still at an early stage.

Mechanistically, postbiotic metabolites have been reported to upregulate tight junction proteins (occludin, claudin-1, zonula occludens-1) via PI3K/Akt signaling, reinforce stratum corneum formation through phosphorylation of HspB1 and filaggrin synthesis, and suppress pro-inflammatory cytokines in models of atopic dermatitis [69,70]. In addition, SCFAs such as butyrate have been shown to reduce dermal inflammation and IL-33 expression caused by S. aureus colonization by inhibiting histone deacetylase activity [71]. These pathways are of direct relevance to agro-residue-derived bioactives, given that fermented cereal, grape, and coffee by-products generate similar metabolite classes (organic acids, phenolic acid derivatives, exopolysaccharides), and therefore constitute plausible candidate substrates for postbiotic production with dermocosmetic applications [49].

Despite this promising mechanistic and early clinical evidence, several key gaps remain. The majority of available in vitro data on agro-residue extracts are derived from antimicrobial assays against a limited set of model organisms (most often C. acnes and S. aureus), which do not capture the complex multi-species ecological networks of the human skin microbiota. Clinical studies incorporating shotgun metagenomic sequencing to evaluate the impact of topically applied agro-residue extracts on the skin microbiome are still scarce, and standardized protocols for skin microbiome sampling remain under development [17,65]. Emerging tools such as “SkinCom”, a synthetic skin microbial community enabling reproducible in vitro investigations that can be compared with human-subject shotgun metagenomics data [72], and novel co-culture systems for commensal skin bacteria are beginning to bridge the gap between bench assays and clinical validation [73]. However, these systems cannot substitute for properly designed, controlled human trials integrating metagenomic endpoints with validated dermatological assessments.

Taken together, the available evidence supports a plausible rationale for microbiome modulation by agro-residue-derived bioactives through prebiotic, antimicrobial, and postbiotic mechanisms [17]. However, the level of clinical substantiation remains insufficient for robust dermocosmetic claims under current regulatory frameworks. Future studies should systematically incorporate metagenomic profiling of the skin microbiome before and after topical application of standardized agro-residue extracts in adequately powered human cohorts, in order to move from promising preliminary data to validated, translatable outcomes [74]. Representative agro-food residue-derived bioactives, their formulation contexts, experimental models, and reported dermocosmetic effects are summarized in

Table 3. Selected bioactive compounds from agro-food residues and their reported dermocosmetic effects.

Bioactive Class (Representative Compound)	Agro-Food Source	Formulation Type	Experimental Model (Level of Evidence)	Physiological Effect	Reference
Flavonoids (Naringenin)	Citrus peel	Topical antioxidant formulation	Keratinocyte culture (in vitro)	ROS reduction, UV protection	[21,22]
Carotenoids (Lycopene)	Tomato residues	Dietary supplementation/topical formulation	Human study (randomized controlled trials, oral)	Reduced UV-induced erythema	[23,24]
Ellagitannins (Punicalagin)	Pomegranate peel	Antioxidant extract	Keratinocyte model (in vitro)	MAPK inhibition, anti-inflammatory activity	[61]
Phenolic acids (Chlorogenic acid)	Coffee silverskin	Topical antioxidant extract	Keratinocyte model (in vitro)	Reduction in oxidative stress	[57]
Phenolic acids (Ferulic acid)	Cereal bran, BSG	Topical antioxidant formulation	Cellular and formulation studies (in vitro)	Photoprotection, antioxidant stabilization	[49]

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4. Industrial and Regulatory Challenges

Despite agro-residue-derived bioactives demonstrating promising biological effects, their integration into industrial dermocosmetic products is limited by technical, toxicological, regulatory, formulation, and economic challenges.

4.1. Standardization and Phytochemical Variability

One of the principal barriers to the industrial valorization of agro-residues lies in their intrinsic qualitative and quantitative variability. Unlike synthetic raw materials, plant-derived residues exhibit significant plasticity, as their phytochemical composition is strongly influenced by genetic background, environmental stressors, agronomic practices, and harvest timing. Abiotic factors such as ultraviolet radiation, temperature fluctuations, water availability, and soil composition dynamically modulate secondary metabolite biosynthesis, leading to marked differences in bioactive profiles across seasons and geographic origins [75]. Consequently, the same residue may exhibit substantial variability in antioxidant capacity, phenolic content, or specific metabolite ratios throughout the year, complicating efforts to ensure product consistency at scale [75].

Seasonal fluctuations can be particularly pronounced. For instance, agro-industrial by-products may display shifts in carbohydrate, ash, protein, or fiber content depending on harvest period, while antioxidant activity and phenolic concentration often peak under stress conditions. In macroalgal residues, protein and bioactive compound levels can vary significantly between winter and summer months. Such variability directly affects extraction yield, bioactivity reproducibility, and downstream formulation performance [75].

To address these challenges, the industry is progressively transitioning from single-marker or total phenolic assays to comprehensive chemical fingerprinting approaches. High-performance liquid chromatography coupled with diode array detection (HPLC-DAD) and tandem mass spectrometry (LC-MS/MS) are increasingly utilized to generate characteristic chromatographic profiles. The integration of chemometric tools, such as Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA), allows manufacturers to define acceptable variability ranges, quantify inter-batch differences, and compare new production lots with validated reference standards. This multivariate approach supports the establishment of defined critical quality attributes (CQAs) and enables the concept of phytoequivalence, which is essential for regulatory approval and industrial reproducibility [76]. In the absence of robust standardization frameworks based on advanced analytical platforms and statistical validation, large-scale implementation of agro-residue-derived ingredients remains technically fragile and commercially uncertain.

4.2. Safety and Toxicological Assessment

Toxicological evaluation and the regulatory framework that governs market access are sometimes presented together, but they address different questions: toxicology asks whether a given material is intrinsically safe under the intended conditions of use, while regulation defines the legal obligations and procedural standards that must be met before that material reaches the consumer. These two dimensions are treated separately in this section [16].

Designating a material as “natural” does not guarantee safety. Agro-residues may contain bioactive compounds that can cause irritation, sensitization, or phototoxic reactions. They are also frequently exposed to contaminants during cultivation, processing, and storage. The extraction process can concentrate both desirable metabolites and impurities, amplifying toxicological risks if not properly controlled [77].

Agricultural raw materials are often subjected to pesticides and herbicides, which may persist as trace residues in biomass and become co-extracted with target compounds [71]. Inadequate storage conditions may further promote microbial growth and mycotoxin production, including aflatoxins and other heat-stable toxins [72]. Additionally, bacterial endotoxins can be introduced during wet processing or handling and are particularly critical for applications involving medical devices or implantable materials, where even low endotoxin levels may trigger severe immunogenic responses [78].

Several well-documented examples illustrate that botanical and agro-residue-derived extracts can raise specific safety concerns. Citrus by-products containing furocoumarins (e.g., bergapten in cold-pressed bergamot oil) have been associated with phototoxic and photogenotoxic reactions, and their use in leave-on cosmetic products has been restricted by the EU Scientific Committee on Consumer Safety [35,36]. Essential oils and extracts from Lavandula spp. and tea tree (Melaleuca alternifolia) have been linked to allergic contact dermatitis, with linalool and limonene oxidation products acting as common skin sensitizers [79,80]. Plant-derived ingredients from species containing pyrrolizidine alkaloids (e.g., comfrey, Symphytum spp.), raise concerns of hepatotoxicity following repeated topical exposure [81]. Herbal raw materials may also carry mycotoxin contamination, including aflatoxins and ochratoxin A, when storage conditions are inadequate [82]. These examples demonstrate that case-by-case risk assessment is requires for agro-residue extracts, since their natural origin neither guarantees safety nor exempts them from the toxicological scrutiny applied to synthetic raw materials.

For cosmetic and dermatological applications, a comprehensive toxicological evaluation is mandatory. Extracts that absorb within the UV-visible range, such as those from citrus peels or pigment-rich residues, require phototoxicity assessment using validated in vitro methods [83,84]. Skin sensitization, irritation, and allergenicity must also be addressed through tiered testing strategies consistent with regulatory frameworks. Advanced analytical control is therefore indispensable. Techniques such as LC-MS/MS are required for multi-residue pesticide screening, ICP-MS for heavy metal quantification, and limulus amebocyte lysate (LAL) assays for endotoxin detection when relevant. The development of a standardized technical dossier for waste-derived feedstocks is a crucial step toward regulatory approval and industrial trust. This dossier should detail impurity profiles, validated analytical methods, and defined acceptance criteria [77].

4.3. Regulatory Framework and Substantiation of Cosmetic Claim

Although the European Commission (EC) Regulation 1223/2009 on cosmetic products, one of the strictest worldwide, does not technically define a “natural product”, it establishes rules that affect this claim [66]. Cosmetic companies often use private standards from independent certification bodies to validate natural claims, which must be truthful, supported by verifiable evidence, and not unclear to consumers [85]. The Regulation restricts or bans certain substances, regardless of whether they are natural or synthetic, based only on their safety for human health. A “natural” product must meet the same strict safety standards as any cosmetic product [66]. However, designing a material as “natural” does not guarantee safety [16]. Agro-residues may contain bioactive compounds that can cause irritation, sensitization, or phototoxic reactions. They are also frequently exposed to contaminants during cultivation, processing, and storage. The extraction process can concentrate both desirable metabolites and impurities, amplifying toxicological risks if not properly controlled [16].

Techniques such as LC-MS/MS are required for multi-residue pesticide screening, ICP-MS for heavy metal quantification, and limulus amebocyte lysate (LAL) assays for endotoxin detection when relevant. The development of standardized technical dossiers or “master files” for waste-derived feedstocks detailing impurity profiles, validated analytical methods, and defined acceptance criteria represents a crucial step toward regulatory approval and industrial trust [86].

Beyond the general safety obligation, the use of efficacy-related cosmetic claims in the European Union is harmonized by Commission Regulation (EU) No 655/2013, which sets six common criteria that all cosmetic claims must meet: legal compliance, truthfulness, evidential support, honesty, fairness, and informed decision-making [40]. The accompanying technical guidance issued by the European Commission in 2017 further specifies that ingredient-related claims, including those referring to “natural” or “upcycled” origin, may not be extrapolated to the finished product unless adequately substantiated [66].

For agro-residue-derived bioactives, this regulatory framework has direct practical consequences. Mechanistic data obtained in vitro, such as enzymatic inhibition, ROS scavenging, or modulation of redox-sensitive transcription factors, are generally insufficient on their own to support a claim of dermocosmetic efficacy on the finished product. According to the technical document on cosmetic claims, ex vivo/in vitro tests must follow standardized protocols. They must be predictive of an in vivo effect and be confirmed in human studies before such effects can be transferred to the product [87]. Therefore, the level of evidence required scales with the type of claim. Descriptive claims about the presence of an ingredient may be supported by analytical data. Performance claims, such as “anti-aging”, “protects against pollution”, “microbiome-friendly”, require properly designed clinical or instrumental studies on the finished product. Such studies need an adequate sample size, controls, and statistical analysis [87].

In addition, claims must not denigrate competitors or mislead consumers, in particular by suggesting that a finished product possesses the properties of one of its ingredients when it does not. Recent guidance and case law have reinforced scrutiny of “green” and “free-from” claims due to the risk of greenwashing in the natural and circular-cosmetics segment [21]. Robust substantiation of agro-residue-based claims, therefore, requires three elements. First, a chemically characterized, batch-controlled extract is needed. Second, there should be a hierarchy of evidence linking molecular composition to mechanistic, ex vivo, and clinical outcomes. Third, a documented product information file must integrate safety, efficacy, and manufacturing data, in line with Articles 11 and 20 of Regulation (EC) No. 1223/2009 [21,38,40,88].

4.4. Skin Bioavailability, Formulation Stability and Realistic Concentration Ranges

A consistent limitation of the literature on agro-residue-derived bioactives is that mechanistic activity demonstrated in cellular models is often discussed without sufficient consideration of skin bioavailability, stability of the active in the final formulation, and realistic concentration ranges achievable in commercial products [12].

With respect to skin bioavailability, most polyphenols possess physicochemical properties that limit their passive permeation through the stratum corneum [12,13]. These properties inlcude high molecular weight (relative to the 500 Da empirical “penetration cut-off” for passive diffusion), multiple hydroxyl groups and moderate to high polarity. Comparative ex vivo studies on excised human skin show several trends. Quercetin penetrates poorly under most conditions, whereas more lipophilic flavanones, such as naringenin and hesperetin, can permeate the epidermis when formulated with penetration enhancers (e.g., D-limonene, lecithin). Hydrophilic phenolic acids such as chlorogenic acid require optimized vehicles (oleogels, O/W microemulsions) to reach measurable concentrations in the dermis [12,13,58]. EGCG from green tea was shown to penetrate excised human skin from a hydrophilic ointment, but the active was highly unstable unless stored cold or co-formulated with antioxidants such as BHT [89]. Encapsulation in nanocarriers (nanoemulsions, solid lipid nanoparticles, nanostructured lipid carriers, chitosan nanoparticles) has been shown to improve cutaneous deposition of polyphenols and carotenoids. This also limits systemic exposure and currently represents one of the most promising strategies to bridge the gap between mechanistic and clinical efficacy [12,13,90].

Regarding formulation stability, many agro-residue-derived bioactives are intrinsically labile. Anthocyanins are sensitive to pH, light, and oxygen. Carotenoids and astaxanthin undergo photodegradation, while tocopherols and unsaturated fatty acids in seed oils are susceptible to autoxidation. Polyphenols can react with metal ions, oxidizing agents, and other reactive ingredients in complex emulsions, leading to color drift and loss of antioxidant capacity over the product’s shelf life [12,13,36]. Stability must therefore be evaluated under realistic storage conditions (long-term and accelerated stability protocols). Interactions with the full vehicle and packaging should be considered, rather than being inferred from antioxidant data on the pure compound.

Finally, realistic concentration ranges in commercial products are often markedly lower than those used in mechanistic experiments. Most plant extracts and extract-derived actives are incorporated in finished cosmetic formulations at concentrations of approximately 0.1–1%, frequently 0.5% or less, which is one to several orders of magnitude below the concentrations used in many in vitro assays [91]. Limited skin penetration and partial degradation in the formulation further reduce effective doses. These means that local epidermal and dermal concentrations of the active compound are typically a small fraction of the doses required for the strongest in vitro effects. This consideration is critical when interpreting any extrapolation of mechanistic findings to claimed cosmetic benefits and reinforces the need to systematically report formulation composition, in-use concentration, and stability data alongside biological activity [91].

4.5. Scalability, Techno-Economic Feasibility and Life Cycle Impact

Although laboratory-scale studies consistently demonstrate promising bioactivity, the translation of agro-residue-derived compounds into industrial cosmetic ingredients requires multidimensional optimization [21]. Demonstration of efficacy under controlled experimental conditions does not automatically ensure manufacturing feasibility. The transition from bench-scale extraction to full-scale production demands coordinated engineering refinement, economic modeling, and environmental validation to balance the interdependent triad of standardization, safety, and scalability [76].

One of the primary constraints arises from phytochemical variability. Seasonal fluctuations, agronomic conditions, and geographic origin can significantly alter metabolite profiles, directly influencing extraction yield, bioactive concentration, and functional reproducibility. To mitigate these inconsistencies, chemical fingerprinting, analytical validation, and robust quality control frameworks are essential to ensure batch-to-batch reliability and regulatory compliance [77].

Green extraction technologies, including ultrasound-assisted extraction (UAE) and supercritical fluid extraction (SFE), offer promising routes for sustainable valorization. However, successful scale-up requires preservation of critical process invariants rather than simple geometric enlargement [76]. In UAE systems, maintaining constant energy density per unit volume is more relevant than amplitude alone, while SFE processes demand strict control of solvent-to-feed ratios, pressure stability, and mass transfer kinetics to replicate laboratory selectivity and yield at an industrial scale. Failure to maintain these parameters may compromise reproducibility and economic viability [21,92].

Beyond technical optimization, financial sustainability must be assessed through techno-economic analysis (TEA). Metrics such as Net Present Value (NPV), Internal Rate of Return (IRR), and Payback Period (PBP) provide quantitative insight into project resilience under fluctuating energy costs, solvent recovery efficiency, and market pricing. Multi-product cascade biorefinery models, where high-value bioactives are extracted first, and residual biomass is subsequently valorized for materials or energy, have demonstrated improved profitability and risk mitigation [93].

Environmental validation is equally critical. Life Cycle Assessment (LCA) enables quantification of environmental burdens across the production chain and frequently identifies electrical energy consumption, particularly for drying, freeze-drying, and solvent evaporation, as a dominant hotspot. Thus, processes labeled as “green” may still impose substantial carbon footprints if energy intensity is not minimized or renewable sources are not integrated. Comprehensive LCA is therefore indispensable to confirm genuine environmental benefit rather than burden displacement [77].

Taken together, phytochemical standardization, rigorous safety evaluation, regulatory compliance, claim substantiation, bioavailability and formulation stability, techno-economic feasibility, and life cycle validation represent interdependent pillars of industrial translation. Only through integrated analytical, regulatory, engineering, and sustainability strategies can agro-industrial residues evolve from promising laboratory resources into reliable, scalable cosmetic ingredients. The principal translational bottlenecks limiting the industrial implementation of agro-residue-derived dermocosmetic bioactives, together with potential mitigation strategies, are summarized in

Table 4. Key translational bottlenecks affecting industrial implementation of agro-residue-derived dermocosmetic bioactives [12,39,46].

Bioactive Class	Main Cosmetic Function	Major Translational Bottlenecks	Industrial Mitigation Strategies
Polyphenols	Antioxidant, anti-aging	Oxidation, extract variability, low skin penetration	Encapsulation, standardized extraction
Carotenoids	Photoprotection	Photodegradation, formulation instability	Lipid carriers, nanoemulsions
Peptide hydrolysates	ECM stimulation	Molecular weight variability, limited dermal penetration	Controlled enzymatic hydrolysis
Polysaccharides	Barrier support	Extraction variability, rheological inconsistency	Standardized purification protocols

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5. Future Directions in Agro Residue-Based Cosmetic Innovation

The advancement of agro-residue-derived bioactives into mainstream cosmetic innovation will depend on integrating digital technologies, systems biology, and industrial optimization frameworks. Beyond overcoming current challenges in standardization and scalability, future progress requires predictive and data-driven approaches that enhance reproducibility and translational precision [94].

Artificial intelligence and machine learning offer promising tools for phytochemical fingerprinting, extraction optimization, and in silico screening of bioactive target interactions. By correlating environmental variables, chromatographic profiles, and biological outcomes, AI-guided systems may improve batch consistency and accelerate candidate selection [89].

The incorporation of multi-omics technologies, including metabolomics and transcriptomics, can further strengthen the link between molecular composition and dermatological mechanisms, enabling more robust claim substantiation and regulatory confidence [95]. These approaches support the emergence of precision dermocosmetics, where bioactives are selected based on pathway-specific modulation tailored to skin phenotype or aging signature [96].

Simultaneously, microbiome-oriented research and biorefinery-based production models represent strategic frontiers. Designing formulations that balance host oxidative pathways and microbial ecology, while integrating cascade valorization processes, may enhance both efficacy and economic resilience [96]. In particular, the systematic integration of shotgun metagenomics, metatranscriptomics, and clinical dermatological endpoints into well-powered controlled studies is required to translate the promising in vitro microbiome-modulating activities of agro-residue extracts into substantiated, regulator-acceptable claims [65,85].

Ultimately, the convergence of circular bioeconomy principles, digital modeling, regulatory harmonization, and systems-level innovation will determine whether agro-industrial residues evolve from sustainable alternatives into scientifically optimized, precision-engineered cosmetic ingredients.

6. Conclusions

Agro-industrial residues represent a structurally diverse and functionally promising source of bioactive compounds with potential dermocosmetic applications. Polyphenols, carotenoids, peptides, and biopolymers derived from food processing by-products have been reported to modulate oxidative stress, extracellular matrix degradation, photodamage, barrier dysfunction, and senescence-associated pathways, supporting their relevance in anti-aging and protective formulations, although the strength of evidence varies considerably across compounds and is dominated by in vitro and animal models, with more limited controlled human data. However, mechanistic efficacy observed at the laboratory scale does not automatically translate into industrial feasibility nor into substantiated cosmetic claims under existing regulatory frameworks. Phytochemical variability, challenges in standardization and safety validation, limited skin bioavailability, formulation stability constraints and the need for proper claim substantiation under EU Regulations 1223/2009 and 655/2013, formulation constraints, and the need for techno-economic and life cycle assessment underscore the complexity of large-scale implementation. The successful integration of agro-residue-derived ingredients into mainstream cosmetics will therefore require coordinated advances in analytical standardization, regulatory harmonization, scalable green extraction, rigorous claim substantiation through ex vivo and clinical studies on finished products, and data-driven formulation design. Through such integrated strategies, agro-residue valorization can evolve from a sustainability concept into a scientifically robust and industrially viable platform for next-generation cosmetic innovation.