气相色谱法同时测定保健食品中的5种 不饱和脂肪酸

Determination of 5 kinds of polyunsaturated fatty acids in dietary supplements by gas chromatography

中文关键词:  气相色谱法  亚油酸  α-亚麻酸  二十碳五烯酸  二十二碳六烯酸  二十二碳五烯酸  保健食品

英文关键词:gas chromatography  linoleic acid  alpha-linolenic acid  eicosapentaenoic acid  docosahexaenoic acid  docosapentaenoic acid  health food

中文摘要:

      目的 建立气相色谱法同时测定保健食品中亚油酸、α-亚麻酸、二十碳五烯酸(eicosapentaenoic acid, EPA)、二十二碳六烯酸(docosahexaenoic acid, DHA)和二十二碳五烯酸(docosapentaenoic acid, DPA)的含量。 方法 样品先采用氢氧化钾甲醇溶液进行皂化处理, 再用三氟化硼甲醇溶液甲酯化, 经HP-FFAP色谱柱(30 m×0.53 mm, 1.0 μm)分离测定。结果 EPA甲酯、DHA甲酯、DPA甲酯、亚油酸甲酯、α-亚麻酸甲酯分别在0.03927~1.178、0.04200~1.260、0.03449~1.035、0.08368~1.255、0.08482~4.241 mg/mL的浓度范围内线性关系良好, 相关系数r均大于0.999; 检出限分别为0.0039、0.0042、0.0034、0.0042、0.0042 mg/mL; 加标回收率在91.1%~109.3%之间, 相对标准偏差均小于5%。结论 该方法操作简单快捷, 适用于保健食品中亚油酸、α-亚麻酸、EPA、DPA和DHA的测定。

英文摘要:

      Objective To establish a method for the determination of linoleic acid, alpha-linolenicacid, eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and docosapentaenoic acid (DPA) in dietary supplements by gas chromatography. Methods The samples were treated by KOH-methanol solution, and methyl esterified using boron trifluoride-methanol complex. Linoleic acid, alpha-linolenic acid, EPA, DHA, and DPA in dietary supplements were separated and detected by HP-FFAP (30 m×0.53 mm, 1.0 μm) column. Results This method showed a good linearity in the range of 0.03927~1.178 mg/mL for methyl EPA, 0.04200~1.260 mg/mL for methyl DHA, 0.03449~1.035 mg/mL for methyl DPA, 0.08368~1.255 mg/mL for methyllinoleic acid, and 0.08482~4.241 mg/mL for methylalpha-linolenic acid with the correlation coefficients higher than 0.999. The limit of detection of methyllinoleic acid, methylalpha-linolenic acid, methyl EPA, methyl DPA and methyl DHA were 0.0042 mg/mL, 0.0042 mg/mL, 0.0039 mg/mL, 0.0034 mg/mL, and 0.0042 mg/mL, respectively, with recovery rates of 91.1%~109.3% and RSD less than 5%. Conclusion This method is simple and rapid, and can be used to determine the content of linoleic acid, alpha-linolenic acid, EPA, DPA, and DHA in dietary supplements.