Increasing the bio-active compounds contents by optimizing the germination conditions of Southern Thai Brown Rice

Abstract

Three Thailand rice varieties (cv. Niaw Dam Peuak Dam, Sangyod Phatthalung and Chiang Phatthalung) were germinatedand their -aminobutyric acid (GABA) content was monitored. Optimum germination conditions to maximize GABAcontent in brown rice were determined. The brown rice was first soaked in various solutions (buffer solution pH 2, 3, 5, and 7and distilled water) at room temperature (30±2°C) for 5 hours, followed by germinating in either open or closed vessel for 12,24, 36, and 48 hours. Results indicated that the highest GABA content was obtained when the rice was soaked in a citratebuffer with pH 3 and germinated in closed vessel for 36 hours, Sangyod Phatthalung and Chiang Phatthalung, and for 48hours, Niaw Dam Peuak Dam. Compared to regular brown rice, the GABA content in germinated brown rice increased 9.43-16.74 times. Germination also increased the ferulic acid 1.12-1.43 times and significantly decreased the phytate content whilethe -oryzanol content was in the same level for both un-germinated and germinated brown rice.

Keywords

• germinated brown rice
• -aminobutyric acid
• ferulic acid
• phytate
• -oryzanol