Abstract: Microbial oil obtained from a yeast strain (Rhodosporidum toruloides Y4#) by acid-heating extraction was characterized, including fatty acid analysis by gas chromatography. The oil was further explored for biodiesel production by lipase-catalyzed methanolysis. Two processes were studied, namely, three-step methanol loading in solvent-free system and all-in-one methanol loading in tert-butanol system. It was demonstrated that the microbial oil could be converted to biodiesel effectively. The biodiesel yield of about 90% could be obtained under the optimized conditions, which was slightly lower than that of refined soybean oil as the raw material.

Key words: microbial oil, biodiesel, lipase, enzymatic transesferification

摘要： 以一株高产油脂圆红冬孢酵母菌(Rhodosporidum toruloides Y4#)干菌粉为原料，利用酸热法提取了该酵母油脂，并对所得油脂进行了分析. 进一步利用该酵母油脂为原料分别研究了无溶剂体系中三步甲醇法及在叔丁醇介质体系中脂肪酶催化合成生物柴油，发现脂肪酶可以有效转化该酵母油脂制备生物柴油. 在优化反应条件下，生物柴油得率可达90%左右，略低于相同条件下利用精制大豆油合成生物柴油的得率.

关键词: 微生物油脂, 生物柴油, 脂肪酶, 生物酶转化