硫元素限制对粘性丝孢酵母油脂积累的影响

Effect of Sulfur Limitation on Lipid Accumulation of Trichosporon fermentans

本论文研究粘性丝孢酵母(CICC1368)在硫元素限制情况下的油脂积累。通过采用低场核磁共振技术监测菌体终点油脂含量;对其生物量、油脂量及脂肪酸组成进行测定;最后,观察了最适碳硫比[n(C)/n(S)]下油脂积累规律。结果显示,低场核磁共振是一种可快速分析微生物中油脂含量的手段。随着碳硫比的改变,可有效调控粘性丝孢酵母中油脂积累,油脂量及油脂得率呈先上升后下降的趋势,因此可将硫元素限制控制在一个合适范围内。适当硫元素限制有利于总不饱和脂肪酸积累,在最适碳硫比为3310时,油酸含量最高可达54.9%,且生物量、油脂产量、干菌体油脂含量可高达21.1g/L,9.0g/L,42.3%。

The effect of sulfur limitation on lipid accumulation of Trichosporon fermentans CICC 1368 were investigated.Firstly,lipid content in microbial cells at the end of fermentation was determined using low field nuclear magnetic resonance (LF-NMR).Then the cell biomass,lipid concentration and fatty acids compositions were assessed.Finally,the lipid accumulation was monitored at the optimum C/S molar ratio.Results showed that LF-NMR can be used as a rapid and effective method to analyze lipid content in microbial cells.Sulfur could effectively control the accumulation of lipids.Lipid content and yield increased first and then decreased as the C/S molar ratio raised,and this indicated that limitation of sulfur should be controlled in an appropriate range.The proper limitation of sulfur would promote the accumulation of the total unsaturated fatty acids,and oleic acid content was up to a maximum of 54.9%.The biomass,lipid concentration,lipid content at a C/S molar ratio of 3310 were 21.1 g/L,9.0 g/L,42.3%,respectively.