Abstract

Physiological activities of hot water (BRW) and 80% ethanol (BRE) extracts from brown rice were investigated in this study. The highest activity (94.9%) of nitrite reductase was observed for BRE at 1 mg/ml at pH 1.2, while the activity for BRW was about 75.4% under the same conditions. The inhibitory effects of BRW and BRE on xanthine oxidase activity were about 39.0 and 72.9% at 10 mg/ml, respectively. The digestibility of starch was lower for brown rice than for milled rice and the highest inhibition (93.1%) of ${\alpha}$-glucosidase activity occurred with BRE. Superoxide dismutase (SOD)-like activities of BRW and BRE were weakly increased in a dose-dependent manner and were about 56.4 and 44.9% at 10 mg/ml, respectively. The influences of BRW and BRE on alcohol metabolizing activity were determined by measuring the generation of reduced nicotinamide adenine dinucleotide (NADH) by alcohol dehydrogenase (ADH) and acetaldehyde dehydrogenase (ALDH). Increases in ADH and ALDH activities were only detected with BRE.

현미의 기능성을 증명하기 위하여 열수, 에탄올 추출하여 여러 가지 생리활성에 대하여 조사하였다. 우선, 아 질산염 소거능 분석에서는 현미 열수와 에탄올 추출물 1 mg/ml 농도, pH 1.2에서 75.4와 94.9%을 나타내었고, xanthine oxidase 저해능은 현미 에탄올 추출물 10 mg/ml에서 72.9%로 같은 농도의 열수 추출물보다 높게 측정되었다. 현미의 소화율($44.46{\pm}6.09$%)은 백미의 소화율($62.71{\pm}4.18$%)보다 낮으며 ${\alpha}$-glucosidase 저해능은 현미 에탄올 추출물 10 mg/ml에서 93.1%로 같은 농도의 열수 추출물보다 높게 측정되었다. 현미 열수와 에탄올 추출물의 SOD 유사활성은 10 mg/ml에서 56.4와 44.9%로 유의적인 큰 차이는 없었다. 현미의 숙취해소 효능은 ADH와 ALDH 활성증진에 현미 열수와 에탄올 추출물이 미치는 영향을 조사함으로써 증명하고자 하였는데 그 결과, 현미 에탄올 추출물에서 알콜 분해능 증가율이 나타났다.

Keywords

• Brown rice;
• nitrite scavenging activity;
• xanthine oxidase;
• ${\alpha}$-glucosidase;
• alcohol metabolizing activity