| The effects of different regulation methods on the growth and oil accumulation of Cryptococcus curvatus N-11 were investigated by shake flask fermentation experiment. The small molecular limiting factors (nitrogen, phosphorus and sulfur) in the medium composition were changed, and the enzyme activity of the key enzyme (malic enzyme) were regulated, and different fermentation modes (batch culture and fed culture) were adopted to study the factors that affected the accumulation of microbial oil and optimize these factors.The results showed that under the conditions of C/N 180.2∶?1, C/P 61∶?1 and C/S 2 413.4∶?1, the oil production and oil content in the yeast cells reached the highest, which were 5 g/L and 68.30%, 5 g/L and 65.99% and 5.53 g/L and 67.11% respectively. The addition of sesamol, a malic enzyme inhibitor, in the culture medium could significantly reduce the ability of yeast to accumulate oil. Fed culture could not only significantly improve the oil production from 4.25 g/L to 9.17 g/L, but also increase the oil content from 65.28% to 74.92%. |
