College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816, China.
Appl Biochem Biotechnol. 2021 Jan;193(1):205-217. doi: 10.1007/s12010-020-03412-9. Epub 2020 Aug 26.
Corncob is an abundant agricultural residue containing high content of hemicellulose. In this paper, the hemicellulosic hydrolysate was prepared from the hydrolysis of corncob using the solid acid sulfated zirconia as a catalyst. According to response surface analysis experiments, the optimum conditions for preparing hemicellulosic hydrolysate catalyzed by sulfated zirconia were determined as follows: solid (sulfated zirconia)-solid (corncob) ratio was 0.33, solid (corncob)-liquid (water) ratio was 0.09, temperature was 153 °C, and time was 5.3 h. Under the optimized conditions, the soluble sugar concentration was 30.12 g/L with a yield of 033 g/g corncob. Subsequently, xylitol production from the resulting hemicellulosic hydrolysate was demonstrated by Candida tropicalis, and results showed that the yield of xylitol from the hemicellulosic hydrolysate could be significantly improved on a basis of decolorization and detoxification before fermentation. The maximum yield of xylitol from the hemicellulosic hydrolysate fermented by C. tropicalis was 0.76 g/g. This study provides a new attempt for xylitol production from the hemicellulosic hydrolysate.
玉米芯是一种丰富的农业残余物，含有丰富的半纤维素。本文采用固体酸硫酸化锆作为催化剂，从玉米芯水解制备半纤维素水解液。根据响应面分析实验，确定了硫酸化锆催化制备半纤维素水解液的最佳条件如下：固（硫酸化锆）-固（玉米芯）比为 0.33，固（玉米芯）-液（水）比为 0.09，温度为 153°C，时间为 5.3 h。在优化条件下，可溶性糖浓度为 30.12 g/L，产率为 033 g/g 玉米芯。随后，通过热带假丝酵母（Candida tropicalis）将得到的半纤维素水解液用于生产木糖醇，结果表明，发酵前进行脱色和解毒处理可以显著提高半纤维素水解液生产木糖醇的产率。由热带假丝酵母发酵半纤维素水解液生产木糖醇的最大产率为 0.76 g/g。本研究为从半纤维素水解液生产木糖醇提供了新的尝试。
