Lipidomics Study Of Yak Butter And Yak Butter Phospholipid

Lipidomics has quickly become a research hotspot since it was proposed in 2003.Based on local characteristics,this study uses yak butter as a starting point and extracts phospholipids from yak butter using solvent extraction to determine the optimal extraction process;to investigate the effects of yak butter and yak butter phospholipids on lipid metabolism of SPF C57 BL / 6J mice;to investigate the effects of yak butter and yak butter phospholipids on lipid metabolism of SPF C57 BL / 6J mice;carry out lipidomics research on yak butter phospholipids and mouse liver;detect the expression levels of lipid metabolism-related genes by Real-time PCR Provide theoretical basis for the functional characteristics of yak butter.The main findings are as follows:(1)Through single factor test and orthogonal test,it was determined that the optimal process for extracting phospholipids from yellow yak butter were determined as follows: liquid-solid ratio 6 m L/g,extraction time 60 min,acetone precipitation time 25 h,extraction temperature 55?.The white yak butter extraction temperature was 45?,the yield was 4.97%,and the purity was 58.09%.Through GC-MS analysis,36 kinds of fatty acids were detected in yak butter,including 26 kinds of SFAs,accounting for more than 73.73% of the total fatty acids,and 10 kinds of UFAs,accounting for more than 24.12% of the total fatty acids;29 kinds of fatty acids were detected in yak butter phospholipids,including 24 kinds of SFAs,accounting for more than 94.28% of the total fatty acids,and 5 kinds of UFAs,accounting for more than 5% of the total fatty acids.(2)Using different extraction solvents(ethanol,isopropanol,ethyl acetate,isohexane,n-hexane)to extract lipids and phospholipids from white and yellow yak butter,the results showed that the yield of lipid and phospholipid extracted from n-hexane in white and yellow yak butter was highest,the lipid yields were 84.32%and 88.86%,respectively;the phospholipid yields were 11.28%and 12.27%,respectively.In addition,fatty acid analysis found that the PUFA and MUFA content of phospholipids extracted from positive hexane was relatively high.Through lipidomics analysis,Six kinds of lipids were detected in negative ion mode in white butter,yellow butter,white butter phospholipids and yellow butter phospholipids:30kinds of PE,17 kinds of PCs,3 kinds of PG,6 kinds of Hex2Cer,5 kinds of PS,7kinds of P1.(3)Yak ghee and phospholipids were fed to the mice and found that the addition of 10% yak ghee to the diet can cause obesity in mice,significantly increasing the levels of TC,TG,LDL and HDL.The effect is similar,but the effect of yak butter phospholipids is relatively small.From the results of HE staining and oil red staining pathological sections,there was basically no significant pathological change in each group after one month of feeding,but after five months of long-term feeding,the yellow butter group,white butter group,yellow butter group phospholipid group,white Different degrees of inflammatory cell infiltration and lipid deposition were seen in the ghee phospholipid group.(4)Real-time PCR was used to detect the expression level of fat metabolism-related m RNAs.After one month of feeding,compared with the blank control group,each experimental group can promote mouse liver tissue FAS,FADS2,FADS1,SCD1,ACSS1,DGAT-1.GPAM,THRSP,HMGCR,CPT1,A-FABP,FABP1 expression(white butter phospholipid group significantly downregulated SCD1,ACSS1,GPAM,HMGCR,A-FABP,FABP1).After five months of feeding,compared with the blank control group,each experimental group can promote the expression of FAS,ACSS1,THRSP,HMGCR in liver tissues of mice,and down-regulate FADS2,FADS1,SCD1,DGAT-1,GPAM,CPT1,A-The expression levels of FABP and FABP1(yellow butter group phospholipid group promotes SCD1 expression,yellow butter group promotes DGAT-1 expression,white butter group promotes FABP1 expression).(5)Lipidomics analysis was performed on the liver tissues of mice after one month of feeding and five months of feeding by UHPLC-QTOFMS.After feeding for one month,9 kinds of lipids were detected in the liver tissues of mice in the blank control group,the yellow butter group,the white butter group,the yellow butter phospholipid group and the white butter phospholipid group,which were PE,PC,PG,Sphingosine,Cer,SM,Hex Cer,DG and TG,respectively.A total of 14 kinds of lipids were detected in the liver tissues of mice in the blank control group,the yellow butter group,and the yellow butter phospholipid group after feeding for five months,which resulted in four glycerophospholipids(PS,PI,PA,CL)and one spongolipid(Hex2Cer).The detected lipids were screened for differential metabolites,and then hierarchical cluster analysis and metabolic pathway analysis were performed for differential metabolites.