Cofermentation with D-glucose and D-xylose mixture by a recombinant industrial strain Saccharomyces cerevisiae

摘要

A previously constructed recombinant Saccharomyces cerevisiae industrial strain NAN-127 containing the xylose metabolic pathway (Ying Wang, et al., 2004) was used for cofermentation with D-glucose and D-xylose. The results showed that the oxygen supply was the most important factor for xylose utilization. Under a charily controlled oxygen-limited condition, the xylose utilization ratio reached 0.655 with 50 g·L~(-1) initial xylose or 0.901 with 20g·L~(-1) initial xylose. The most favorable fermentation condition was obtained with pH kept at 4.5, ventilation rate kept at 0.04 L·L~(-1)·min~(-1).Feed addition of furfural after lag phase with a rate of 0.125 g·L~(-1)·h~(-1) diminished the xylitol yield by 26% under micro-aeration condition without inhibiting the growth of strain NAN-127.