圆红冬孢酵母利用生物柴油副产物粗甘油产油脂的影响因素分析

以餐饮废油制备生物柴油的副产物粗甘油为碳源，采用圆红冬孢酵母发酵生产微生物油脂。通过对发酵影响因素的优化，确定了最适发酵条件为:种子复苏时长24 h、富集时长10 h、接种量为6%、初始粗甘油浓度为60 g/L、C/N为60、有机氮占总氮比例为75%、发酵体积为100 mL、发酵温度为30 ℃、发酵时间为6 d，在此条件下，获得总产油量为10.56 g/L，油脂产率为0.229。与无机氮源硫酸铵相比，有机氮源蛋白胨的添加显著提高了油脂含量和总产油量。通过测定油脂的脂肪酸成分并利用Hoekman方程估算所得生物柴油的性能指标，表明其符合中国、美国及欧盟标准。该方法既为粗甘油的再利用提供了一条新途径，又为生物柴油的生产提供了廉价的原材料。

INFLUENCING FACTORS ANALYSIS OF LIPID PRODUCTION BY RHODOSPORIDIUM TORULOIDES USING CRUDE GLYCEROL,A BY-PRODUCT FROM BIODIESEL PREPARATION FROM WASTE COOKING OIL

In this study, crude glycerol, a by-product in the process of biodiesel preparation from waste cooking oil, was used as carbon source to produce microbial lipid by Rhodosporidium toruloides. Through the optimization, the optimized fermentation conditions were determined as follows: seed resuscitation time of 24 h, enrichment time of 10 h, inoculation rate of 6%, initial crude glycerin concentration of 60 g/L, ratio of carbon to nitrogen of 60, organic nitrogen ratio to total nitrogen of 75%, fermentation volume of 100 mL, fermentation temperature of 30 ℃ and fermentation time of 6 d. Under the optimal condition, lipid production and lipid yield rate reached 10.56 g/L and 0.229, respectively. Compared with inorganic ammonium sulfate, the addition of organic peptone significantly increased the lipid content and lipid production. The performance of biodiesel was estimated by measuring the fatty acid composition of lipid and using Hoekman equation, which met all of the standards of China, the United States and the European Union. This study can not only provide a new strategy for the reutilization of crude glycerol, but also provide a economical raw material for the production of biodiesel.