Analysis Of Main Chemical Components Of Olive Leaf And Lipid-lowering Efficacy

In the middle of the last century,China began to promote the cultivation of olive trees in the northwest region.The main purpose was to process olive oil.With the expansion of the olive tree planting area,annual need to be trimmed,and the trimmed leaves are as much as600,000 tons.However,due to the lack of awareness of the potential value of olive leaf,and there is no ideological basis and relevant support for production and processing,the treatment of leaves in China is generally burning.Not only did not make full use of the potential value,but also caused waste and pollution.Therefore,it is necessary to carry out deep research on olive leaves.Plant polyphenols have a variety of health effects,and olive leaf is also rich in polyphenols,but its chemical composition research and biological activity research is not deep enough.In this paper,gas chromatography-mass spectrometry(GC-MS),ultra-high performance liquid chromatography(UPLC),and time-of-flight mass spectrometry(Q-TOF-MS)were used to analyze aroma components and non-volatile chemical components in olive leaves.At the same time,the lipid-lowering effects of olive leaf extracts on high-fat diet-induced hyperlipidemia animals were studied.The experimental results are as follows:1)Analysis of the aroma components of leaves and shoots of olives combine GC-MS with HS,SDE and SPME three sample preparation methods.The results showed that olive leaves and shoots contained a lot of aldehydes,esters and aromatic heterocycles.The relatively high content of aldehydes are Hexanal and Benzeneacetaldehyde;The relatively high content of esters are 5-vinyl-3-picolinic acid methyl ester and dibutyl phthalate;The relatively high content of aromatics and heterocyclics are Butylated Hydroxytoluene(BHT)and 3-vinylpyridine.In general,the higher aroma content in the leaves are dexacene,2,6-di-tert-butyl p-cresol and methyl 5-vinyl-3-picolinateand,The buds contained Hexanal,Butylated Hydroxytoluene(BHT)and 5-vinyl-3-picolinic acid methyl ester.2)UPLC analysis of the contents of hydroxytyrosol and oleuropein in the three places of olive leaf.The results showed that the contents of oleuropein in olive leaves were higher in Longnan City of Gansu Province,while the hydroxytyrosol content in Mianyang City of Sichuan Province was higher,and the contents of olive leaves in Qianjiang City of Wuhan Province were both low.3)The molecular ion peak and ion fragment of the compound represented by thechromatographic peak directly shown by the Q-TOF-MS total ion chromatogram.14 compounds were identified based on relevant literature and ion fragment information.The main compounds were Hydroxytyrosporol glucoside,oleoside,secologanoside,elenolic acid glucoside,2"-hydroxy oleuropein,Verbascoside,Oleuropein and Ligstroside.4)Through the construction of mouse high-fat model,the results of the intervention show that compared with the high-fat control group,the weight of mice fed with olive leaf extract(high dose p<0.001),abdominal Fat(high dose p<0.05)and liver weight(low dose p<0.01,high dose p<0.001)were significantly suppressed.5)Olive leaf extract has a certain hypolipidemic effect,due to a shorter intervention time,so compared with the high-fat control group,significant lipid-lowering efficacy(TG,TC,HDL-C)is only seen with high-dose interventions.TG(p<0.001),TC(p<0.05),HDL-C(p<0.001).6)Olea leaf active substance can inhibit the lipid peroxidation of the body.Compared with the high-fat control group,the serum MDA level is only significantly inhibited by high-dose intervention(p<0.05).However,GPX levels increased significantly with low and high doses(p<0.01,p<0.001).Hepatic Lipid Antioxidant Markers: Compared with the high-fat control group,MDA levels were significantly inhibited under low and high doses(p<0.05,p<0.001).However,SOD levels only increased significantly with high-dose interventions(p<0.05).7)Olive leaf extract does not lead to elevated levels of AST and ALT,suggesting that drinking it will not result in liver toxicity.Compared with the high-fat control group,the ALT levels in the high-dose group and the low-dose group are significantly lower(p<0.01,p<0.01).However,AST levels were significantly lower(p<0.05)only with high-dose interventions.