利用气相色谱法分析不同萃取方法对鱼油中EPA、DHA含量的影响

Effect of Different Extraction Methods on the Content of EPA and DHA in Fish Oil by Gas Chromatography

本文利用气相色谱法(GC)对鱼油中的二十碳五烯酸(EPA)和二十二碳六烯酸(DHA)进行了定量分析,探究了快速检测EPA、DHA的分析条件,并以黄鲛鱼鱼胃为原料,利用建立的色谱分析方法分别测定了超声强化亚临界水萃取法、超声波辅助溶剂萃取法、酶解提取法和超临界CO_2萃取法获得的鱼油样品中的EPA和DHA的含量。结果显示:EPA的出峰时间是10.015 min,DHA的出峰时间是16.500 min。升温程序和分流比会显著影响目标峰(EPA、DHA)与其相邻峰的分离度R_1和R_2(p<0.01)。该法与国标GB5009.168-2016中的脂肪酸色谱分析方法相比,具有针对性强(可快速检测EPA、DHA)、准确性高、重现性好和快速高效的特点,样品分析时间由82 min缩短至18 min。在最佳分析条件下,上前述四种萃取方法获得鱼油中含有的EPA的检出量依次是54.67、35.23、40.13、33.40 mg/g,DHA的检出量依次是134.01、77.50、102.30、67.31 mg/g。

EPA and DHA in fish oil were quantitatively analyzed by gas chromatography（ GC ） , and the analysis conditions for rapid detection of EPA and DHA were explored.The content of EPA and DHA in fish oil from stomach of spanish mackerel fish by ultrasound enhanced subcritical water, ultrasound assisted organic solvent, enzyme hydrolysis and supercritical CO2 extraction were determined using the rapid GC analysis method.The results showed the peak time of EPA was 10.015 rain,and DHA was 16.500 min. The heating program and shunt ratio could significantly affect the separation degree of the target peak （EPA, DHA）and its adjacent peak R1 and R2 （p 〈 0.01 ）. Compared with the chromatography analysis method of fatty acids recommended in GB5009.168-2016,the method had advantages of strong pertinence（ fast detection of EPA and DHA）, high accuracy, good reproducibility and high efficiency. The analysis time was shortened from 82 min to 18 min. Under the best analysis conditions,the content of EPA in fish oil were 54.67,35.23,40.13 and 33.40 mg/g, respectively, DHA were 134.01, 77.50,102.30 and 67.31 mg/g,respectively.