Establishment And Application Of Analytical Methods Of The Squlaene And Alkylglycerols In Shark Liver Oil

Squalene and alkylglycerols are two kinds of natural active substances in shark liver oil, which have a variety of physiological active functions and can be widely used in medicine, health products and cosmetics. In this paper, methods for the determination of squlaene and alkylglycerols in shark liver oil were developed.The effects of fish oil refining process on the contents of squlaene and alkylglycerols were also researched. The main research contents are as follows:A method for squlaene analysis in shark liver oil by gas chromatography-mass spectrometry (GC-MS) was researched.Using hexacosane as the internal standard, an internal standard method for squalene determination in shark liver oil by GC-MS was developed, and the impact caused by the different saponification conditions on the determination of squalene was also studied. The results showed that the best saponification conditions were as follows: The oil sample was saponified with 50 g/L methanol KOH, 80℃water bath heating, 0.5 h, then extraced with hexane/chloroform. The linear range of the method was 0.01～0.20 mg/mL(R2=0.9983). The detection limit of squlaene was 0.93 ng. The recoveries of squalene were 91.46%～100.37%. The RSD was 1.86% (n=6). The method has been successfully applied in the determination of squalene in 7 kinds of shark liver oils. It was a simple, rapid, accuracy and featuring high sensetivity method for the determination of squalene.A method for alkylglycerols analysis in shark liver oil by GC-MS was studied. Using hexacosane as the internal standard, an internal standard method for alkylglycerols determination in shark liver oil by GC-MS was developed, and the best saponification conditions were chosen by orthogonal experiments. The results showed that the best saponification conditions were as follows: The oil sample was saponified with 0.5 mol/L alcoholic KOH, 80℃water bath heating, 1.5 h, then extraced with hexane. The upper solution was dried and esterified with acetic anhydride. The linear range of the method was 0.02～0.10 mg/mL(R2=0.9991). The detection limit of alkylglycerols was 3.16 ng. The recoveries of alkylglycerols were 102.65%～106.62%. The RSD was 3.26% (n=6). This method was simple, rapid and high sensitivity.The effects of fish oil refining process on the contents of squlaene and alkylglycerols were researched. The results showed that squlaene and alkylglycerols in refined oils lost 47% and 39% respetively compared with crude oils. The loss of squlaene and alkylglycerols in the degumming process were rarely, in the bleaching and de-aciding process, the loss of squlaene and alkylglycerols were about 5%. However, the loss of squlaene and alkylglycerols in the deodorizing process were respectively 36% and 27%. As a result, this fish oil refining process should be optimized in order to retain more of the squlaene and alkylglycerols.