THE EFFECT OF DIFFERENT FACTORS ON MICROBIAL OIL PRODUCTION BY TRICHOSPORON FERMENTANS ON RICE STRAW ACID HYDROLYSATE

Microbial oil production by Trichosporon fermentans was carried out on the rice straw acid hydrolysate in this work. In order to reduce the detoxification cost, activated carbon was used as absorbent. The effect of peptone concentration, inoculum size, cultural temperature, and initial pH on the lipid fermentation of T. fermentans was evaluated that initial pH showed more significant influence than other three factors. The optimal peptone concentration, inoculum size, cultural temperature, and initial pH for the lipid production were 0.6 g/L, 10%, 25 degrees C, and 7.0, respectively. Under the optimal condition, the highest lipid yield of T. fermentans was 12.1 g/L (corresponding to 31.0 g/L biomass and 39.0% lipid content) after 10 days' fermentation. This work showed that low-cost activated carbon could be utilized for detoxification of rice straw acid hydrolysate, and T. fermentans is a promising strain for microbial oil and thus biodiesel production from lignocellulosic biomass.