Di Serio, Teresa (2025) Innovative active ingredients for skin health: from natural and upcycled sources to synthetic derivatives. [Tesi di dottorato]

Documento PDF diserio_teresa_38.pdf Download (6MB)

Abstract

Skin ageing is a complex and multifactorial biological process driven by interconnected molecular mechanisms, including oxidative stress, mitochondrial dysfunction, cellular senescence, chronic inflammation, and extracellular matrix (ECM) degradation. These alterations progressively compromise the structural and functional integrity of the skin, leading to decreased elasticity, uneven pigmentation, and impaired barrier function. From a physiological perspective, skin ageing represents a natural and unavoidable process. Nevertheless, a comprehensive understanding of the underlying molecular and cellular pathways is essential to identify strategic biological targets and to design interventions able to maintain skin functionality and homeostasis. Within this framework, the present doctoral project aimed to develop and characterise innovative active ingredients for modulating the biological mechanisms associated with skin ageing and skin alterations, with the ultimate goal of promoting skin longevity. Particular attention was given to natural bioactive compounds, whose intrinsic structural diversity and multifunctional profiles make them promising candidates for the development of safe, effective cosmetic topical formulations. In this scenario, my research work focused on the study of different natural sources, including botanical, fungal, microbial, and agri-food by-products. In particular, these matrixes were valorised through an up-cycling approach in line with models of sustainability. Specifically, I investigated the adaptogenic and anti-ageing potential of a Cordyceps sinensis mycelium extract, the skin-protective properties of exhausted Citrus limon (L.) peels derived from Limoncello liqueur production and the properties of humic substances extracted from composted fennel residues for their potential role in restoring skin balance. However, aware of the intrinsic limitations of natural molecules - such as volatility, instability, and unfavourable organoleptic properties - this project also extended to the evaluation of a synthetic molecule, phenylalanine butyramide (C₁₃H₁₈N₂O₂, FBA), a butyric acid derivative investigated as a potential skin-lightening and depigmenting agent. To achieve these objectives, a multidisciplinary approach was employed, combining chemical characterisation with in vitro cellular assays and in vivo clinical trials on healthy volunteers to assess the biocompatibility, biological functionality, and cosmetic efficacy of the investigated ingredients. Instrumental assessments of key skin parameters - such as skin hydration, elasticity, brightness, and wrinkle reduction - have further confirmed the cosmetic efficacy and skin tolerability of the ingredients investigated in this project. Overall, this doctoral research outlines a scientifically grounded strategy for the development of innovative cosmetic actives, combining sustainability, technological innovation, and biological efficacy. By bridging molecular understanding with ingredient design, this work contributes to the advancement of safe and functional cosmetic formulations aimed at supporting skin longevity and preserving skin health over time.

Downloads

Actions (login required)

Modifica documento