Determination Of Volatile Substances And Fatty Acids In Elymus Elm L.by GC-EI/NCI-MS

In this paper,the volatile substances and fatty acids of Elaeagnus angustifolia were detected and analyzed by gas chromatography-mass spectrometry(GC-MS),and the methodology of gas chromatography-negative chemical ionization mass spectrometry(GC-NCI-MS)was evaluated.The results are as follows:The volatile compounds of Elaeagnus angustifolia were detected after three different rough processing,which were unprocessed,fried and cooked by microwave,among which microwave ripening showed advantages in the detection of volatile substances.A total of 25 components were detected in the detection of volatile substances,and 16 kinds of substances were detected by microwave cooking.The fatty acid part is also divided into three rough processing methods: unprocessed,fried and microwave cooked,and the fatty acids are derived from potassium hydroxide and methanol solution.It is found that there are eight kinds of fatty acids in elm pod kernel.Microwave ripening method detected the most kinds of substances,up to 8 kinds.In the part of methodological evaluation,the fatty acids of elm pod kernel cooked by microwave were detected by GC-NCI-MS,and the derivatization results of potassium hydroxide methanol solution and propyl chloroformate(PCF)were compared.The negative chemical ionization mass spectrometry of 8 kinds of methyl ester and 8 kinds of propyl ester were obtained,which provided reliable data for the establishment of negative chemical ionization mass spectrometry library.Finally,the methodological index was detected with PCF as derivative.the results showed that the method was linear and correlated well.According to the detection of the two standard products,the detection limit and quantitative limit of the method were as follows: n-octanoic acid,and the detection limit was 0.08mmol/L.The quantitative limit was 0.27 mmol/L,the detection limit was 0.01 mmol/L,the quantitative limit was 0.04mmol/L,and the corresponding values were 0.35% and 0.03%,respectively.The reproducibility of n-octanic acid and n-decanoic acid was 1.81% and 0.41%,respectively,and the recovery of n-octanic acid and n-decanoic acid was 80%-120%,and the coefficient of variation was 0%-5%.It can be used as a feasible method for the detection of fatty acids in the same crop.Its significance lies in the use of the GC-MS method,which combines the separation ability of GC and the structural analysis advantages of MS,and the unique advantages of GC-NCI-MS method in some fields.Two main nutrients of Elaeagnus angustifolia,a new food raw material,were detected.It also plays a role in perfecting the data in the establishment of negative chemical source ionization spectrum database,which lays a foundation for future research.In the aspect of methodology,the indexes were tested and the effective data were obtained,and a new fatty acid detection method was established.