罗氏海盘车性腺脂质的微波提取及其成分分析

Microwave-assisted extraction of Asterias rollestoni gonad lipids and its component analysis

为优化罗氏海盘车性腺脂质的微波提取工艺并分析其脂质成分和脂肪酸组成,该研究采用微波辅助提取技术对罗氏海盘车性腺脂质的提取工艺进行优化,同时通过核磁共振和气相色谱-质谱分别对其脂质成分和脂肪酸组成进行分析。试验结果表明,罗氏海盘车性腺脂质的最佳提取工艺条件:以乙酸乙酯为提取溶剂、液料比7 mL/g、提取时间12 min、提取温度60℃,在此优化条件下,罗氏海盘车性腺脂质的提取率为33.82%。罗氏海盘车性腺脂质的主要成分为甘油三酯和磷脂,胆固醇和游离脂肪酸含量较低;脂肪酸以C14:0、C16:0、C18:1n-7、C20:1n-11、C20:5n-3(eicosapentaenoic acid,EPA)和C22:6n-3(docosahexaenoic acid,DHA)为主,C20:5n-3和C22:6n-3总质量分数为21.56%,且n-3型与n-6型多不饱和脂肪酸的比值高达8.72;同时罗氏海盘车性腺脂质的脂肪酸致动脉粥样硬化指数(atherogenic index,AI)和血栓形成指数(thrombogenic index,TI)分别为0.81和0.29,表明罗氏海盘车性腺脂质能有效预防动脉粥样硬化和血栓形成,具有很高营养价值和脂质开发潜力,可作为C20:5n-3和C22:6n-3等功能性脂肪酸的重要膳食来源。该研究为罗氏海盘车性腺脂质的微波提取、成分分析和综合开发利用提供了一定的理论依据。

Asterias rollestoni is the starfish belonging to the phylum Echinodermata, class Asteroidea. Asterias rollestoni is widely distributed in Chinese waters. The resource of Asterias rollestoni is abundant, and the amount is up to hundreds of thousands of tons every year. Moreover, Asterias rollestoni is rich source of valuable bioactive components, such as lipids, proteins, asterosaponin and polysaccharides. Therefore, Asterias rollestoni has high nutritional values and development potentials as raw materials for marine drugs and functional foods. Extensive investigations of Asterias rollestoni on chemistry and pharmacology have been published in ample literatures at present, but no literature has been reported on Asterias rollestoni gonad lipids, especially on lipid extraction and component analysis. In order to optimize the lipid extraction technology and analyze the lipid and fatty acid compositions of Asterias rollestoni gonads, the extraction process of Asterias rollestoni gonad lipids was performed by microwave-assisted extraction, and the lipid and fatty acid compositions were also studied by nuclear magnetic resonance（NMR） and gas chromatography-mass spectrometry（GC-MS） respectively in this paper. Taking extraction rate as an index, the effects of extraction solvent, liquid-solid ratio, extraction time and extraction temperature were studied through the single-factor experiment and the orthogonal experimental design. The experimental results indicated that the optimal extraction process of Asterias rollestoni gonad lipids was as follows： ethyl acetate as solvent, liquid-solid ratio of 7 mL/g, extracting time of 10 min, and extracting temperature of 60 ℃. On the optimized conditions, the extraction yield was up to 33.82%, showing that microwave-assisted extraction method had the advantages of high efficiency and low energy consumption, and had a great application prospect for lipid extraction of Asterias rollestoni gonads. The predominant components of Asterias rollestoni gonad lipids were triglycerides and phospholipids, while the contents of cholesterol and free fatty acids were relatively low. Meanwhile, C14：0, C16：0, C18：1 n-7, C20：1 n-11, C20：5 n-3（eicosapentaenoic acid, EPA） and C22：6 n-3（docosahexaenoic acid, DHA） were the main fatty acids, and the content of C20：5 n-3 and C22：6 n-3 accounted for 21.56% of total fatty acids. Moreover, the contents of n-3 and n-6 polyunsaturated fatty acid（PUFA） were respectively 23.62% and 2.71%, and the ratio of n-3 to n-6 polyunsaturated fatty acids was up to 8.72, which was significantly higher than the daily dietary ratio of n-3 to n-6 polyunsaturated fatty acids recommended by Food and Agriculture Organization of the United Nations（FAO） and the World Health Organization（WHO）. Polyunsaturated fatty acids, especially C20：5 n-3 and C22：6 n-3 had positive effects on promoting the development of the nervous system and curative effects on preventing cardiovascular disease and anti-inflammatory. Additionally, the atherogenic index（AI） and thrombogenic index（TI） of Asterias rollestoni gonad lipids were 0.81 and 0.29, respectively. In conclusion, Asterias rollestoni gonad lipids have high nutritional values and great exploitation prospects, and can prevent effectively atherosclerosis and thrombosis, and also can be the important dietary sources of C20：5 n-3 and C22：6 n-3. The experimental results provide the theoretical basis for microwave-extraction, component analysis and comprehensive utilization of Asterias rollestoni gonad lipids.