Colloidal gas aphrons (CGA) fractions of red grape (Vitis vinefera) pomace: potential applications in cosmetics

Degradation of extracellular matrix proteins by collagenase and elastase is the main contributing factor to skin aging. Inhibition of these enzymes by polyphenols from natural extracts might be promising approach but permeation into the skin is limited due to large molecular structure. Surfactants have been used in cosmetic products to help with the permeation. Here the application of a surfactant-based separation technique, Colloidal Gas Aphrons (CGA) to the extraction of polyphenols from grape pomace and their inhibitory activity against collagenase and elastase is investigated. The inhibitory activity of ethanolic (EE) and hot water extracts (HWE) of grape pomace and their CGA fractions  was measured. Both extracts inhibited both enzymes in dose-dependent manner with IC50 values of 78.8mg/L and 34.5mg/L for collagenase; 18.7mg/L and 35.5mg/L for elastase. CGA fractions from EE inhibited 66.7% of collagenase and 39% of elastase, while HWE fractions inhibited 54.9% and 6.3% collagenase and elastase, respectively. CGA fractions were enriched in epicatechin, resveratrol, caffeic acid and quercetin. In conclusion, HWE showed higher inhibition potency but CGA fraction from EE demonstrated higher inhibition against both enzymes. Overall, this study showed the potential of  the CGA fractions for application in cosmetics.