不同前处理方法对微拟球藻脂肪酸组成的影响

Effect of Different Methods of Oil Extraction on Fatty Acid Composition of Nannochloropsis

采用直接甲酯化、乙醚抽提、正己烷提取等3种方法对微拟球藻进行前处理,用索氏法提取油脂,经气相色谱分析,对比前处理方法对微拟球藻油脂提取率及脂肪酸组分的影响。结果表明:乙醚提取藻粉油脂的提取率(微藻的油脂质量分数)为12.70%,正己烷提取藻粉油脂的提取率为11.00%,乙醚提取油脂的提取率大于正己烷的提取率;直接甲酯化后测得微拟球藻脂肪酸中多不饱和脂肪酸(Polyunsaturated Fatty Acids,PUFAs)质量分数为20.04%,多不饱和脂肪酸中二十碳五烯酸(Eicosapentaenoic Acid,EPA)含量最丰富,占总脂肪酸13.0%;经过乙醚和正己烷提取后的油脂,脂肪酸组成更加简单,PUFAs含量明显增加,乙醚提取油脂EPA含量是直接甲脂化法的2.3倍,正己烷提取所得油脂EPA含量是直接甲脂化法的2.08倍。

Fatty acids in nannochloropsis were extracted by three esterification, ethyl ether extraction and n-hexane extraction different methods, i.e., methyl After being detected by gas chromatography （GC）, the effect of different pretreatment methods on extraction effect and fatty acids composition were analyzed. Results show that the oil extraction ratio of nannochloropsis extracted by ethyl ether and n-hexane was 12.70% and 11.00%, respectively. Under methyl esterification, polyunsaturated fatty acids （PUFAs） content of 20.04% and eicosapentaenoic acid （EPA） content of 13.0% were obtained, while the fatty acid composition of oil extracted by ethyl ether and n-hexane were simpler than that extracted by methyl esterification method, and their PUFAs content increased significantly, and the content of EPA in PUFAs extracted by ethyl ether was 2.3 times as much as that by methyl esterification, and that extracted by n-hexane was 2.08 times as much as that by methyl esterification.