GC法同时测定鸦胆子油中4种脂肪酸的含量

目的建立同时测定鸦胆子油中棕榈酸、硬脂酸、油酸和亚油酸4种成分含量的方法。方法采用毛细管气相色谱法,甲酯化后测定鸦胆子油中棕榈酸、硬脂酸、油酸和亚油酸的含量。色谱柱:DB-17弹性石英毛细管柱(30 m×0.25 mm×0.25μm),检测器:氢火焰离子化检测器(FID),柱温恒温:200℃(保持11 min),进样口温度:250℃,检测器温度:250℃,流速:1.0 mL.min-1,分流比:20∶1,内标物:苯甲酸苯酯。结果棕榈酸、硬脂酸、油酸和亚油酸的线性分别为74～738 mg.L-1(r=0.999 6)、51～509 mg.L-1(r=0.999 1)、741～7 410 mg.L-1(r=0.999 1)和265～2 650 mg.L-1(r=0.999 1);各成分的平均回收率(n=9)分别为94.6%、94.2%、94.2%和95.3%。结论此方法可为鸦胆子油的质量评价提供依据。

GC determination of four fatty acids in Brucea javanica (L.) Merr. oil simultaneously

Objective To establish a method for the determination of palmitic acid, octadecanoic acid,oleic acid and linoleic acid in Brucea javanica (L.) Merr. oil simultaneously. Methods The sample was determined with capillary column DB-17 (30 m × 0.25 mm × 0.25 mm) by GC coupled with flame ionization detector. Temperature was maintained at 200 ℃ for 11 min. The injector temperature was 250 ℃. The detector temperature was 250 ℃. The flow rate was 1.0 mL·min^-1. Split injection was conducted with split ratio of 20: 1. Nitrogen was used as carrier gas. Results The calibration curve was linear within the range of 74-738 mg·L^-1 ( r = 0.999 6), 51-509 mg·L^-1 ( r = 0.999 1), 741-7410 mg·L^-1 ( r = 0.999 1) and 265-2650 mg·L^-1 (r = 0.999 1) for palmitic acid, octadecanoic acid, oleic acid and linoleic acid, respectively. The average recoveries (n = 3) were 94.6 %, 94.2 %, 94.2 % and 95.3 % for palmitic acid, octadecanoic acid, oleic acid and linoleic acid, respectively. Conclusions This method is convenient, accurate and reproducible for the determination of palmitic acid, octadecanoic acid, oleic acid and linoleic acid in Brucea javanica (L.) Merr. oil.