Chemical Constituents From The Leaves Of Hovenia Acerba Lindl. And Their Inhibitory Activity Against ?-glucosidase

Hovenia acerba Lindl.?Rhamnaceae?is widely distrib?ted in most area of China.As a medicinal plant,traditional Chinese medicine believes that it has the functions of relieving wine,protecting liver,clearing heat,diuresis and so on.It is mainly used for hangover,fever,thirst,and urination.In recent years,the researchers of both at home and abroad study the chemical constituents and pharmacological activities of H.acerba Lindl..they report lots of chemical constituents such as terpenoids,flavonoids,alkaloids,as well as its oxidation resistance,protecting liver,activity,anticancer therapy,etc.In order to elucidate its pharmacodynamics furtherly,we study on the chemical constituents of the leaves of H.acerba Lindl..By using organic solvent extraction,normal phase silica gel column,reversed-phase column silica gel?RP-18?column,Sephadex LH-20 gel column,polyamide column chromatography,high performance liquid chromatography?HPLC?methods,we conducted the separation of 85%ethanol extracts of H.acerba and afforded 19 compounds,16 of them were identified as ?-Linolenic acid?1?,linoleic acid?2?,stearic acid?3?,kaemperol?4?,quercetin?5?,daucosterol?6?,caffeic acid?7?,2-methylenesuccinic acid?8?,Itaconic acid 4-methyl ester?9?,trans-aconitic acid?10?,trans-aconitic acid 5-methyl ester?11?,trans-Aconitic acid a-ethyl ester?12?,trans-aconitic acid 6-methyl ester?13?,trans-aconitic acid 6-methyl ester?14?,trans-aconitic acid 1-methyl ester?15?,trans-aconitic acid 1-ethyl ester?16?by spectral analysis?NMR?and comparing the spectral data.Among them,chemical compounds8¹0,12¹6 was separated from this plant for the first time.We introduced a high through screening bioassay on ?-glucosidase inhibition which adopts PNPG as the substrate,use the ?-glucosidase from yeast,and a positive control of acarbose.The screening bioassay model was validated by testing its enzyme activity,enzyme concentration,substrate concentration,temperature and inhibitory activity of positive control.Most of the compounds were tested for their ?-glucosidase inhibitory activities,and most of them exhibits certain inhibitory activity at the concentration level of25?g/mL.Among them,compound 4?JHA 04?showed a better activity with an IC₅₀ value of 3.10?g/mL?10.83?M?.Positive control acarbose showed an IC₅₀ value of 0.008?g/ml?0.012?M?.We conducted the chemical constituents research on the leaves of H.acerba and tested the obtained compounds through an ?-glucosidase inhibition activity screening.The results enriched the chemical constituents of the genus of Hovenia,and indicated the flavonoids were the active antidiabetic materials,and laid a foundation for the further research and application for the leaves of H.acerba Lindl..