Akdeniz University, Faculty of Engineering, Department of Food Engineering, Antalya 07058, Turkey.
Bioresour Technol. 2013 May;135:365-71. doi: 10.1016/j.biortech.2012.09.006. Epub 2012 Sep 10.
In this study, optimization of ethanol production from carob pod extract was carried out by immobilized Saccharomyces cerevisiae. Results showed that Ca-alginate concentration and the amount of immobilized cells had significant effects on yield. Optimum conditions for ethanol fermentation were determined to be 2% Ca-alginate concentration, 150 rpm agitation rate, 5% yeast cells entrapped in beads and pH 5.5. After validation experiments; ethanol concentration, yield, production rate and sugar utilization rate were respectively 40.10 g/L, 46.32%, 3.19 g/L/h and 90.66%; and the fermentation time was decreased to 24 h. In addition, the immobilized cells were shown to be reusable for five cycles, though a decrease in yield was observed. Finally, carob pod extract was used for ethanol fermentation by controlled and uncontrolled pH without any enrichment, and the results suggest that carob extract can be utilized effectively by immobilized-cell fermentation without the use of enrichments to facilitate yeast growth.
本研究采用固定化酿酒酵母对角豆荚提取物进行乙醇生产的优化。结果表明，海藻酸钠浓度和固定化细胞的添加量对角豆荚乙醇产量有显著影响。确定乙醇发酵的最佳条件为：2%海藻酸钠浓度、150rpm 搅拌速率、5%包埋在珠中的酵母细胞和 pH5.5。经过验证实验，乙醇浓度、产率、生产速率和糖利用率分别为 40.10g/L、46.32%、3.19g/L/h 和 90.66%，发酵时间缩短至 24 小时。此外，固定化细胞可重复使用五轮，但产率有所下降。最后，通过控制和不控制 pH 值对角豆荚提取物进行乙醇发酵，无需任何富集，结果表明，固定化细胞发酵可有效利用角豆荚提取物，无需使用富集物来促进酵母生长。
