富含EPA微藻油超声波辅助溶剂法提取工艺优化及脂肪酸成分分析

Optimization of the solvent extraction with ultrasonic assistance and fatty acid analysis of the microalgae oil enriched EPA

目的以富含EPA的微拟球藻(Nannochloropsis sp.)为原料,优化超声波辅助溶剂萃取法提取EPA微藻油的提取方法,并对提取出的藻油脂肪酸组成进行分析研究。方法将样品按一定料液比加入提取溶剂,充分混合后在水温一定的超声设备中超声浸提一定时间。浸提后置于3000 r/min转速下离心5 min,取上清液旋转蒸发后于105℃下烘干至恒重得藻油。将提取出的藻油甲酯化后利用气相色谱分析其脂肪酸组成。结果提取微藻油的最佳工艺为:50℃,超声30 min,液料比15:1(m L/g),提取3次,在该条件下微藻油得率为37.6%。气相色谱分析显示,所得EPA占总微藻油脂肪酸的39.0%。结论该方法简便、溶剂环保、藻油得率高、脂肪酸组成中EPA含量高,适合微拟球藻油提取。该工艺为EPA微藻油产业化提取提供了科学依据。

Objective To optimize the extraction method of eicosapentaenoic acid microalgae oil by solvent extraction with ultrasonic assistance, with Nannochloropsis sp. riched in EPA as raw materials, and analyze the composition of fatty acid of the extracted microalgae oil. Methods Samples were added at a certain ratio of liquid extraction solvent, and extracted for a certain time with ultrasonic assistance after thorough mixing. Then the mixed samples were centrifuged at speed of 3000 r/min with 5 min. At last, the supernatant were dried via rotary evaporation method and then were dried at 105 ℃. The extracted microalgae oil＇s fatty acid compositions were analyzed by gas chromatography after methyl esterification. Results The optimal extraction conditions were as follows： temperature 50 ℃, extraction time 30 min, liquid-solid ratio 15：1, 3 times of extraction. The extraction rate of microalgae oil reached 37.6% under the optimal extraction conditions. Gas chromatography analysis showed that EPA, the main component of the microalgae oil was 39.0% in total fatty acids. Conclusion The proposed method is simple, and can get high extraction rate of microalgae oil and high content of EPA, which is suitable for extracting microalgae oil from Nannochloropsis sp. The technology will provide a scientific basis for industrialization of microalgae oil of EPA.