State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China.
Appl Biochem Biotechnol. 2013 Dec;171(8):2093-104. doi: 10.1007/s12010-013-0278-z. Epub 2013 Sep 12.
A new bioprocess for production of sorbitol and gluconic acid from two low-cost feedstocks, inulin and cassava starch, using a commercially available enzyme was proposed in this study. The commercial glucoamylase GA-L NEW from Genencor was found to demonstrate a high inulinase activity for hydrolysis of inulin into fructose and glucose. The glucoamylase was used to replace the expensive and not commercially available inulinase enzyme for simultaneous saccharification of inulin and starch into high titer glucose and fructose hydrolysate. The glucose and fructose in the hydrolysate were converted into sorbitol and gluconic acid using immobilized whole cells of the recombinant Zymomonas mobilis strain. The high gluconic acid concentration of 193 g/L and sorbitol concentration of 180 g/L with the overall yield of 97.3 % were obtained in the batch operations. The present study provided a practical production method of sorbitol and gluconic acid from low cost feedstocks and enzymes.
本研究提出了一种利用两种低成本原料（菊粉和木薯淀粉）和一种市售酶生产山梨醇和葡萄糖酸的新工艺。研究发现，商业用酶 Glucoamylase GA-L NEW（Genencor 公司生产）具有较高的菊粉酶活性，可将菊粉水解为果糖和葡萄糖。该酶可替代昂贵且无法商业化获得的菊粉酶，用于同时糖化菊粉和淀粉，得到高浓度的葡萄糖和果糖水解液。利用固定化重组运动发酵单胞菌全细胞，将水解液中的葡萄糖和果糖转化为山梨醇和葡萄糖酸。在分批操作中，获得了 193 g/L 的高葡萄糖酸浓度、180 g/L 的山梨醇浓度和 97.3%的总收率。本研究提供了一种从低成本原料和酶生产山梨醇和葡萄糖酸的实用方法。
