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

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.