VICTORIA DONAT*, ANNA MARTÍ
*Corresponding author
Textron Técnica (Grupo Plimon), Barcelona, Spain

Abstract

We aimed to develop a novel lipid-based skin whitener and personal care product to replace syntethic bioactives. Additional qualities were intended as safety, naturalness, preservative absence and thermal stability. To this purpose, a broad study was performed to identify vegetable oils and botanical extracts, in order to produce a lipid solution showing skin whitening, hydrating and nourishing activities. The product obtained using selected ingredients was subsequently submitted to performance assessment, safety assays and physico-chemical characterization. Efficacy trials evaluated the whitening activity of the product under ex-vivo conditions after 4 doses, at 100% concentration, using reconstructed human epidermis and displaying a 47% reduction of melanin quantity versus the negative control. Safety was proved by dermatological assays. Key parameters as density, viscosity, acidity, peroxide and saponification values were determined, fatty composition analyzed by gas chromatography, and oxidative stability tested by Rancimat method, revealing full suitability for cosmetic use.

INTRODUCTION

Melanin is the natural pigment of human skin. Tyrosinase is responsible for melanization in plants and animals, which leads to – sometimes undesirable – browning. Tyrosinase is a melanogenic copper-containing enzyme that catalyzes the transformation of tyrosine to dopaquinone, eventually leading to melanin secretion and subsequent accumulation in skin cells (1, 2).

Effects of UV radiation on the skin are both beneficial and harmful. It induces synthesis of vitamin D, killing of pathogens and treating the disorders like psoriasis. On the other hand, they cause photoaging and skin cancer by making alterations in the cellular levels (3). The exposure of UV radiation on the skin generates oxidative stress resulting in structural and functional changes in the epidermis and biomolecules present within the cell.

Various dermatological disorders, such as melasma, age spots, and sites of actinic damage arise from the accumulation of an excessive level of epidermal pigmentation (1, 4-6). Although melanin has mainly a photoprotective function in human skin, the accumulation of an abnormal amount of melanin in different specific parts of the s ...