OPTIMIZED EXTRACTION OF PHENOLIC COMPOUNDS FROM BARLEY (HORDEUM VULGARE L.) SEED AND THEIR RADICAL SCAVENGING PROPERTIES

Extraction of phenolic compounds from barley (Hordeum vulgare L.) seed was optimized by using a designed experiment including three process variables, i.e., temperature (45-60C), time (3-6 h) and ethanol concentration (65-80%). The extraction temperature and time were found significant (P < 0.05) process variables and maximum of 2.18 mg GAE/g dried seed powder of total phenolic compounds was obtained by extraction at 60C for 6 h using 65% ethanol. Regression analysis and response surface method were used for the prediction of optimum levels of process variables which were 58C temperature, 5.4 h time and 65% ethanol for the maximum amount of total phenolic compounds (2.31 mg GAE/g seed powder) from barley that showed a good experimental validation (2.28 mg GAE/g seed powder of phenolic compounds). All the extracts prepared from barley seed showed good antiradical activities that ranged between 52 and 65.24%; the highest was achieved by the optimized extract.