ANTIOXIDANT AND ANTIOBESITY ACTIVITIES OF SEED EXTRACT FROM CAMPBELL EARLY GRAPE AS A FUNCTIONAL INGREDIENT

ABSTRACT This study was an initial step to evaluate grape seeds from the waste products of the food industry as nutraceutical materials. Grape seeds of Campbell Early cultivar (Vitis labrusca × Vitis vinifera) were dried and pulverized followed by extraction with absolute methanol. The total phenolic content of grape seed extract (GSE) was 80.82 mg gallic acid equivalent/g seed. The amount of total flavonoids was 27.04 mg (+)‐catechin equivalents/g of grape seed. GSEs exhibited antioxidant activities of 60.13 mg ascorbic acid equivalent/g seed and 209.45 mg Trolox equivalent/g seed for 1,1‐diphenyl‐2‐picrylhydrazyl and 2,2′‐azino‐bis(3‐ethylbenzthiazoline‐6‐sulphonic acid), respectively. GSE inhibited lipid accumulation of C3H10T1/2 and 3T3‐L1 cells in a dose‐dependent manner. Inhibition was also associated with reduced expression of PPARγ, the master regulator of adipocyte differentiation. Further study is needed to identify specific molecules which attribute bioactivities of GSE. PRACTICAL APPLICATIONS Overall, the observed antioxidant and antiobesity activities of Campbell Early seeds suggest that they could be used as a functional and nutraceutical ingredient as well as preservative ingredient in foods. Results verified the efficacy of new value‐added material from agricultural by‐products. Eventually, we plan to develop a natural antioxidant additive using GSE in expectation of retarding lipid oxidation and providing other functionality.