提高木糖和葡萄糖乙醇产率的菌种驯化

ACCLIMATIZATION OF STRAINS FOR INCREASING ETHANOL YIELD FROM GLUCOSE AND XYLOSE

为提高酵母菌代谢木糖和葡萄糖产乙醇的效率,以木糖为底物对利用木糖和葡萄糖的3株酵母菌进行驯化培养,通过对糖的利用率和乙醇产率的分析表明,经7个批次的驯化,3个菌株的木糖利用率和乙醇产率都得到了明显提高。驯化后的3个菌株经固定化细胞乙醇发酵,结果表明,ATCC 32728(P.tannoph ilis)的木糖利用率为87.90%(36h),葡萄糖利用率为99.99%(24h),混合糖(70g/L,木糖∶葡萄糖=2∶5,24h)利用率为93.95%,乙醇产率达到了99.99%。Pachysolen tannoph ilis ATCC 32728经驯化,并用固定化细胞进行乙醇发酵,使混合糖的利用率和乙醇产率达到了理想的效果。

Three strains of yeasts with xylose as the sole carbon source were domesticated for increasing the efficiency of ethanol conversion. The utilization rate of glucose and xylose of the 3 strains were increased significantly after acclimatizing 7 batches. The results of ethanol fermentation obtained by using immobilized cells indicated that xylose utilization rate (36 h), glucose utilization rate (24 h), and mixed sugar (70 g/L, xylose: glucose = 2:5 utilization rate) (36 h) was 87.9%, 99.99% and 93.95%, respectively with a ethanol yield of 99.99% by strain Pachysolen tannophilis ATCC 32728. The ideal utilization rate of mixed sugars and ethanol production rate were obtained by the adapted Pachysolen tannophilis ATCC 32728. with immobilized cells.