Polyphenols extracted from red grape pomace by a surfactant based method show enhanced collagenase and elastase inhibitory activity

BACKGROUND: The aim of this study is to separate polyphenols from grape pomace using a surfactant-based separation, Colloidal Gas Aphrons (CGA) and to investigate their inhibitory activity against skin relevant enzymes, collagenase and elastase. Ethanolic (EE) and hot water crude extracts (HWE) were produced first and then the CGA generated using TWEEN20 were applied resulting in polyphenols enriched fractions (CGA-EE and CGA-HWE, ethanol and hot water extracts derived fractions respectively). RESULTS: Both crude extracts inhibited the enzymes in a dose-dependent manner however, further extraction by CGA led to fractions with higher inhibitory efficiency against collagenase. Although gallic acid was the main component of the CGA-HWE, others such as kaempferol must have contributed to its potency which was over six times more than gallic acid's. The CGA-EE was found to be about four times more efficient than its crude extract and over six times more efficient than gallic acid in collagenase's inhibition; quercetin was the major polyphenol in this fraction. CONCLUSION: It is evident that ethanol and hot water extraction processes led to different polyphenols composition and thus different inhibitory activity against collagenase and elastase. Further separation with CGA increased the inhibitory potency of both extracts against collagenase. Overall the results here showed the potential application of the CGA fractions from grape extracts in cosmetics.