| Brown rice was made of paddy through removing husk, consisting of pericarp, seed coat, aleuronic layer, embryo, endosperm, rich in many vitamins, mineral elements and functional substances good for human health. It can germinate under proper environmental conditions. Some researches indicated the nutritional value of germinated brown rice was better than brown rice, much better than polished rice. Japan take the leading position in the research on brown rice germination, and a series of germinated brown rice products have been launched on the markets, In China, research on brown rice germination had scarcely carried out. With the increase of people's life level and health awareness, nutritive and functional food would be pay substantial attention. As Chinese main meal, the research and development of nutritive and functional rice and its products would get interest. Therefore, in this paper, the research of the effect of temperature, gibberellic acid (GA3) and Ca2+ on amylase activities, main composition and physiological indexes in brown rice germinating was carried out. The results were as fellows:Nutritive compositions and their changes of brown rice from japonica rice variety "liao jing 294"during germination were investigated. It was showed that the contents of total amino acid and reducing sugar in brown rice were higher than polished rice (Chinese main meal), but lower than the germinated brown rice; Amylase activity in brown rice in the process of germination at 16 ~28 were investigated, -amylase and total starch enzymatic activities in brown rice germination at given temperature range were increased. The peak of amylase activity in the plot of amylase activity over time came up earlier at 28 than at 22 and 16 , but the highest amylase activity could be observed at 22 . Compared to -amylase, - amylase activity in brown rice was less dependent on temperature. During the period of brown rice germination, starch content in germinated brown rice decreased as amylase activity increased, however, reducing sugar content increased at the beginning, and then decreased at the end period.Brown rice treated with GA3 at 0.02, 0.2and 2.0mg. L-1, the same indexes described above of brown rice were investigated. It was showed that at the range of 0.02 to2.0mg. L-1, GA3 could improve germinating energy, germination percentage, germination index, vigor index, shoot length and amylase activity of brown rice significantly (p < 0.05), comparedwith untreated control group. The increase of these indexes above was strong positive correlation with GA3 concentration. In the meantime, starch and storage protein hydrolysis was accelerated, consequently the contents of reducing sugar, soluble protein and free amino acid in germinating brown rice increased. The optimum GA3 concentration was 0.2 mg. L-1Effect of exogenous Ca2+on the germination activity and several physiological and biochemical indexes of brown rice were determined. The respiration rate of brown rice rose with the increase of Ca2+concentration at the range of 0 to 15mmol. L-1. Low Ca2+ concentration (0.05-0.5mmol. L-1) could not only enhance the germination potential, germination rate, germination index and vigor index, but also enable storage substances (e.g. starch, protein) to degrade. Those indexes mentioned above would decrease with the increase of Ca 2+ concentration. When Ca2+concentration was up 5.0 m mol. L-1, inhibition effects were observed. The optimum Ca 2+ concentration was 0.5mmol.L-1.The role of exogenous Ca2++GA3 played in the induction of amylase activity was investigated during brown rice germination. Treating the brown rice with 0.5mmol. L-1 Ca2+ in combination of GA3 (0.02mg. L -1~2.0mg. L-1), amylase activity, the velocity of starch degradation and the content of reducing sugar increased. Of which, the combination of 0.5mmol. L-1 Ca2+ with 0.02mg. L-1 was optimum. Reducing sugar content had strongcorrelation with the amylase activity.
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