Citrus peel wastes as functional materials for cosmeceuticals

Abstract

The suitability of CPWs, by-products of the juice industry, was investigated as a source for the production of cosmeceuticals. Four kinds of CPWs, CW, CWE, CWER, and CWEA, were examined for their antioxidant potentials in terms of DPPH radical-scavenging ability for anti-wrinkle applications, inhibition of tyrosinase or melanin production for whitening products, and anti-inflammatory effects to treat various skin diseases such as atopic dermatitis and acne as well as for anti-bacterial activity against acne-inducing pathogens. Of the four extracts, CWER was the most potent tyrosinase inhibitor (IC50 value: 109 μg/mL), and CWEA (ICO50: 167 μg/mL) showed good antioxidative effects. CWE and CWEA samples had dose-dependent inhibitory effects on the melanin production. The cytotoxic effects of the four CPWs were determined by colorimetric MTT assays using human keratinocyte HaCaT cells. Most extracts exhibited low cytotoxicity at 100 μg/mL. These results suggest CPWs are attractive candidates for topical applications on the human skin.