Valorisation des coques de cacao par production d’extraits antioxydants, anti-inflammatoire et anti-mélanogénèse pour des essais de formulation de produits cosmétiques.

Abstract

Cocoa shells generate vast amounts of waste in the cocoa industry. This study focuses on valorizing these husks for the cosmetics industry. We developed various extraction processes through decoction, ethanolic maceration, and hydro-ethanolic maceration of cocoa husks from Trinitario and Forastero varieties, followed by a phytochemical screening. Subsequently, we evaluated the potential of the extracts to modulate oxidative stress by assessing lipid peroxidation inhibition and measuring their total antioxidant capacity. The anti-inflammatory activity was studied by examining the inhibition of nitric oxide (NOº) production and the inhibition of 5-lipoxygenase. Regarding anti-melanogenesis activity, it was determined by analyzing tyrosinase inhibition. The most active extract was then selected for the formulation testing of an exfoliating cream and an anti-acne soap. The results indicate that the extract obtained through hydro-ethanolic maceration of Forastero (FAE) exhibits the highest levels of phenolic compounds (39±0.16 mgEq AG/g of extract) and flavonoids (14.61±0.24 mgEq quercetin/g of extract). Furthermore, FAE demonstrates a more pronounced antioxidant activity with an IC50 of 6.7±0.07 µg/ml for lipid peroxidation inhibition compared to ascorbic acid (IC50=4.4±0.09 µg/ml), which was used as a reference compound. For anti-inflammatory activity, FAE showed superior effects with an IC50 of 4.31±1.43 µg/ml for NOº production inhibition and an IC50 of 0.41±0.02 µg/ml for 5-lipoxygenase inhibition, in comparison to baicalin (IC50 values of 0.12±0.02 µg/ml and 0.71±0.15 µg/ml, respectively). Additionally, FAE significantly inhibited tyrosinase (IC50=53.85±7.76 µg/ml) compared to ascorbic acid (IC50=43.23±6.46 µg/ml). A scoring calculation was subsequently employed, revealing that the FAE extract generally exhibited the best biological activities sought after in this study. Ultimately, this extract at a concentration of 100 µg/ml was selected for the formulation testing of an exfoliating cream and an anti-acne soap, which are currently undergoing efficacy tests. These findings contribute to the valorization of cocoa husks by producing active ingredients for dermocosmetics as a replacement for certain synthetic products. This approach not only creates a new source of income for cocoa farmers but also offers a sustainable waste management solution within this sector.