Blessings in disguise: Bio-functional benefits of grape seed extracts

Grapes (Vitis vinifera) are one of the largest fruit crops in the world, with an annual production of 69 million metric tons. They are a good source of polyphenolic compounds and 60-70% of these polyphenols, especially phenolic acids, ellagitannins, flavonols, flavan-3-ols such as catechins and their isomers, anthocyanins, proanthoojanidins and the stilbene derivative resveratrol exist in grape seeds. Grape seeds comprise 5% by-mass of grapes and are the major industrial by-products from grape processing industries such as grape juice and wine industries. Nowadays, grape seed extracts (GSEs) are receiving increased interest from scientists, nutritionists and consumers as a result of their reported potential health benefits for a variety of disorders. They are widely being consumed as a dietary supplement on the basis of their potent anti-oxidant, anti-cancer, antimicrobial, anti-aging, anti-hepatotoxic and anti-inflammatory activities and also have generally recognized as safe status approved by Food and Drug Administration. The beneficial activities of the grape seeds give them the possibility to be used in pharmaceutical and food industries, for medical treatments and health supplements. The review summarizes current knowledge on the bioactivities of grape seeds and provides tools for those intending to conduct research in this field as large quantities of grape seeds are discarded as waste from the wine making industry. Therefore, this by-product resulting from the grape industry could be utilized through results of diverse studies on their bioactivities. (C) 2015 Elsevier Ltd. All rights reserved.