The anthocyanin composition of a red grape pomace in relation with the wine industry by- products valorization in animal feed

Abstract

Grape pomace (GP), by-product of wine making, contains a large part of antioxidant polyphenols originating from the input material, the grapes. High production volumes, environmental impact and nutritional content of grape pomace makes it an important subject for careful valorisation. In order to valorize it, it is necessary to determine its chemical composition in bioactive molecules. In this study the anthocyanins were determined by LC-MS from a dried red grape pomace from Valea Călugărească, Romania. Based on their retention times, UV-VIS and MS spectra using standard compounds one anthocyan and three anthocyanidins were identified and quantified from GP acetone extract: peonidin 3-O-glucoside, delphinidin, cyanidin and malvidin. The most abundant anthocyanidin is delphinidin (23.93 ±0.12 μg/mL acetone extract) followed by malvidin (10.01 ±0.06 μg/mL acetone extract), the anthocyan peonidin 3-O-glucoside (4.78 ±0.04 μg/mL acetone extract) and cyanidin (2.63 ±0.06 μg/mL acetone extract). The results show that GP contains anthocyans and anthocyanidins, which possess anti-inflammatory and anti- carcinogenic activity, cardiovascular disease prevention, obesity control, and diabetes alleviation properties, all of which are more or less associated with their potent antioxidant property.