从实验室保藏的15株酵母中筛选获得一株油脂产量相对较高的酵母菌KC 8，经96 h摇瓶发酵培养后，油脂产量为1.22 g/L。利用分子生物学鉴定，该菌株的26S rDNA序列与胶红酵母（Rhodotorula mucilaginosa）具有100%相似性；以KC 8为出发菌株，经ARTP诱变，最终从300株诱变存活菌株中筛选得到高产油脂突变菌株Y3，经96 h摇瓶发酵培养后，油脂产量为2.38 g/L；对菌株Y3的培养条件进行优化，菌株在葡萄糖为碳源，硫酸铵为氮源，碳氮比为90∶1，培养基初始pH为6.5时，在28℃恒温条件下摇瓶发酵培养96 h后，油脂产量最高达到了3.96 g/L；GC-MS对油脂组分进行分析结果表明，该脂肪酸主要由棕榈油酸、油酸、亚油酸、硬脂酸、二十碳烯酸和二十四烷酸组成，与植物油成分相似。%A high lipids producing strain, KC 8, was selected from 15 yeast strains which were stored in our lab. KC8 could produce 1.22 g/L lipids after 96 h flask fermentation. Analysis on the 26S rDNA sequence indi-cated that KC 8 had 100%identity with Rhodotorula mucilaginosa. Using KC 8 as a starting strain, atmospheric and room temperature plasma (ARTP) was used to induce mutation for screening strains of higher lipids pro-duction. Finally, Y 3 was obtained from 300 strains of screening. The yield of lipid was 2.38 g/L after 96 hours flask fermentation by Y 3. After optimized the fermentation conditions, the lipid productivity reached 3.96 g/L under the following conditions:glucose as carbon source, (NH4)2SO4 as nitrogen source , ratio of carbon to ni-trogen at 90∶1, initial pH 6.5, incubated at 28℃for 96 h shaking fermentation. Gas chromatography-mass spectrometer(GC-MS) analysis indicated that the fatty acids were mainly composed of palmic acid, oleic acid, linoleic acid, stearic acid, eicosenoic acid and tetracosanoic acid. The compositions of fatty acids were similar to those of vegetable oil.
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