The Hypoglycemic And Hypolipidemic Active Ingredients With Its Mechanism Research Of Hawthorn

In order to promote the development of hawthorn,the separation,purification,structure identification and mechanism of active substances in Hawthorn polyphenols and polysaccharides were studied in this paper.And the composition analysis and activity evaluation of Hawthorn extracts were also carried out.The main research methods and results are as follows:?1?The‘shanlihong'hawthorn was selected as material.The active components were separated by activity-directed isolation method,which combine with organic solvent sequential extraction,Thin layer chromatography,column chromatography and so on.The mechanism of the active constituents of Hawthorn polyphenols was studied by UV spectrophotometry and fluorescence chromatography.And the structure of the active constituents was identified by nuclear magnetic resonance spectroscopy combined with literature data.The results showed that the ethyl acetate fraction?AF?had the highest?-glycosidase and pancreatic lipase inhibition activity,and their IC₅₀ values were?98.26±0.21??g/mL and?6.37±0.61?mg/mL.The dichloromethane fraction?DF?had the highest cholesterol esterase inhibition activity and DPPH radical scavenging,and their IC₅₀ values were?6.88±0.26?mg/mL and?65.31±0.21??g/mL.Five compounds?A-E?were isolated from AF,and their structures were identified as ursolic acid?B?,kaempferol?D?,quercetin?E?.The structures of Compound A and Compound C are yet to be further characterized.The results of the activities of compound B,C,D,E show that this compounds exhibited different strengths of?-glucosidase,pancreatic lipase inhibitory activity,and DPPH?scavenging ability,of which E?quercetin?had the strongest inhibitory and scavenging ability.The inhibition mechanism of quercetin on?-glucosidase was studied.The results showed that the inhibition of?-glucosidase by quercetin was reversible and non-competitive inhibition,and the inhibition constant Ki was calculated to be 0.08 mmol/L.Further studies have shown that the reason for quercetin can inhibit the activity of?-glucosidase is it can change?-glucosidase conformation.?2?Taking‘shanlihong'hawthorn as materials,the active components of hawthorn polysaccharide were separated by activity-directed isolation method,which combine with organic solvent degreasing,ultrasonic assisted hot water extraction,ethanol precipitation,Sevage,membrane separation,column chromatography and so on.The mechanism of the active constituents of hawthorn polysaccharides was studied by ultraviolet spectrophotometry and fluorescence chromatography.The primary structure of the active homopolysaccharide was identified by infrared spectroscopy,GPC and pre-column derivatization-HPLC.The results showed that the six polysaccharide fractions?PCF1-PCF6?were isolated from blueberry leaf polysaccharides.PCF1 had the highest?-glycosidase and pancreatic lipase inhibition activity.The uniform polysaccharide PCF1-1 was obtained by further purified.The inhibition mechanism of PCF1-1 on?-glucosidase was studied.The results showed that the inhibition of?-glucosidase by PCF1-1 was reversible and mixed-type inhibition,and the inhibition constant Ki was calculated to be 0.66 mg/mL.The primary structure of PCF1-1 was determined.The results showed that the weight average molecular weight Mw was 26530 Da,the number average molecular weight Mn was8755 Da,and the Z average molecular weight Mz was 7.339×10⁴ Da.It consists of nine monosaccharides of sugar,glucuronic acid,galacturonic acid,glucose,galactose,arabinose and fucose.Its characteristic functional groups were analyzed by Infrared spectroscopy.?3?Using the‘shanlihong'hawthorn as material,the lipid extract was obtained by petroleum ether extraction method.The biological activity was determined by ultraviolet spectrophotometry.At the same time,the physicochemical properties were determined.The fatty acid composition of the lipid extract was analyzed by gas chromatography-mass spectrometry?GC-MS?.The results showed that the lipid extract has a certain inhibitory effect on?-glucosidase and pancreatic lipase,and also has a ability to scavenge DPPH?.The results also showed that acid value of the lipid extract was?62.73±0.92?mg/g,peroxide value was?12.98±0.35?mmol/mL,saponification value was?593.89±3.21?mg/g,iodine value was?102.82±0.91?g/100g.The lipid extract consists of 10 fatty acids,mainly unsaturated fatty acids,mainly linoleic acid?44.47%?,linolenic acid?24.76%?,palmitic acid?12.26%?,and myristic acid?6.23%?.