Studies On The Chemical Constituents And Their Bioactivities Of Hypericum Seniawinii Maxim.

Hypericum seniawinii Maxim.is a perennial herb of the genus Hypericum in the family Guttiferae,widely distributed in temperate regions,growing in grasslands and ridges on mountain slopes.It has been widely used in China as a folk medicine for the treatment of inflammatory and infectious diseases,and is often taken as a whole herb to regulate menstruation and activate blood circulation,clear heat and dampness,and detoxify and reduce swelling.In recent years,flavonoids,flavonoid glycosides and sugars have been isolated from the plant,but the chemical composition and biological activity of this plant have been little investigated.In order to further investigate the material basis of the activity of the herb,the present work was carried out to isolate and identify the chemical constituents and their in vitro cytotoxic,neuroprotective and antiinflammatory activities using the whole plant from Yuexi,Anqing,Anhui Province..Objective: In this study,monomeric compounds were obtained from the aboveground part of Hypericum seniawinii Maxim.by means of systematic isolation and structural identification,and the monomeric compounds were screened for cytotoxic,neuroprotective and anti-inflammatory activities in vitro.Methods: Various chromatographic techniques,such as silica gel column chromatography,thin layer chromatography,C18 reverse column,Sephadex LH-20 gel column,semi-preparative high performance liquid chromatography and high performance liquid chromatography,were used for the separation and purification of the chemical components from Hypericum seniawinii Maxim..The compounds isolated were structurally characterized by means of physicochemical and spectroscopic analysis,and the absolute conformation of the compounds was determined by validation methods such as calculation of ECD and hydrolysed sugars.For the pharmacological activity,the compounds were screened for acetylcholinesterase inhibition,in vitro cytotoxic activity using the Cell Counting Kit-8(CCK-8)colourimetric assay(three common humanderived tumour cell lines: human breast cancer cells MDA-MB-231,human non-small cell lung cancer A549 and human liver cancer cells Hep G2),and the effect of compounds 1-6 on corticosteroids was determined.The compounds were screened for their protective effects against corticosterone-induced PC12 cell damage and for their anti-inflammatory activity against LPS(lipopolysaccharide)induced RAW264.7macrophages.Results: A total of 13 compounds,including two novel benzophenone glycosides,were isolated and identified from the dichloromethane extracts of the plant,and were recorded as hypersens A(1)and B(2)and 11 known compounds,compared with the data reported in literatures,they were identified as(S)-(+)-5,7-dihydroxy-2-(1-methylpropyl)chromone(3),5,7-dihydroxy-2-isopropylchromone(4),urachromone B(5),3-8’’ bisapigenin(6),luteolin(7),quercetin(8),kaempferol(9),farrerol(10),ethyl chlorogenate(11),5,9-dihydroxy-2,2-dimethyl-2H,6H-pyrano[3,2-b]xanthen-6-one(12),petiolin G(13).In summary,a systematic study of the chemical composition of the plant produced in Yuexi,Anhui Province was carried out,and 13 compounds,were isolated,10 of them were found in the plant for the first time,which enriches the study of the plant and deepens the understanding of the chemical composition of the plant of the genus Hypericum.Through multiple activity screening,only compound 6 showed weak acetylcholinesterase activity at a concentration of 50 μM with an inhibitory rate of 16.62± 1.04 %.In addition,the inhibitory rate of compound 6 at 10 μM concentration was35.51 ± 6.13 % in the screening of LPS-induced RAW264.7 cells.Compound 6(3-8’bisapigenin)was found to exhibit potential anti-inflammatory activity,and the possible mechanism of its anti-inflammatory action was tentatively explored,which is of great significance for the further development and utilization of medicinal plants of the genus Hypericum.