School of Life Science, Soochow University, Suzhou 215123, China.
Appl Biochem Biotechnol. 2010 Nov;162(5):1471-82. doi: 10.1007/s12010-010-8926-z. Epub 2010 Feb 25.
The production of fermentable sugars from rice hull was studied by dilute acid pretreatment and enzymatic saccharification. Rice hull (15%, w/v) was pretreated by 1% (v/v) sulfuric acid at high temperature (120 approximately 160 degrees C) for 15, 30, 45, and 60 min, respectively. The maximum sugar concentration from rice hull in the prehydrolysate was obtained at 140 degrees C for 30 min, but the enzymatic saccharification yield from the corresponding pretreated rice hull is not high. To another aspect, the maximum enzymatic saccharification yield was achieved at 160 degrees C for 60 min, while the recovery of fermentable sugars was the poorest. To take account of fermentable sugars from pretreatment and enzymatic saccharification, the maximum yield of sugars was obtained only when rice hull was treated at 140 degrees C for 30 min. Under this condition, 72.5% (w/w) of all sugars generated from the raw material can be recovered. The kinetic study on the enzymatic saccharification of dilute acid pretreated rice hull was also performed in this work by a modified Michaelis-Menten model and a diffusion-limited model. After calculation by a linear and a non-linear regression analysis, both models showed good relation with the experimental results.
采用稀酸预处理和酶解糖化的方法从稻壳中生产可发酵糖。将稻壳（15%，w/v）分别用 1%（v/v）硫酸在高温（120 至 160°C）下预处理 15、30、45 和 60 min。在 140°C 下预处理 30 min 时，稻壳预水解液中获得了最大的糖浓度，但相应预处理稻壳的酶糖化产率不高。另一方面，在 160°C 下预处理 60 min 时，可获得最大的酶糖化产率，而可发酵糖的回收率最差。考虑到预处理和酶解糖化过程中的可发酵糖，只有当稻壳在 140°C 下预处理 30 min 时，才能获得最大的糖产率。在此条件下，从原料中产生的所有糖的 72.5%（w/w）可以回收。本工作还通过改进的米氏方程和扩散限制模型对稀酸预处理稻壳的酶糖化动力学进行了研究。通过线性和非线性回归分析计算后，两个模型均与实验结果具有良好的相关性。
