Studies On The Secondary Metabolites And Bioactivities Of Hypericum Japonicum Thunb.and Marine-derived Fungi Aspergillus Ochraceus

Hypericum japonicum Thunb.ex Murray,as a type of annual herb,belongs to the genus Hypericum（family Guttiferae）.It mainly distributed in Asia,Oceania and North America,as well as in parts of China.It is of great practical value in traditional medicine.The results of modern pharmacological studies indicated that Hypericum japonicum can be used in the treatment of bacterial diseases,infectious hepatitis,acute and chronic hepatitis,gastrointestinal diseases,internal bleeding and tumors,etc.According to the reported literature,there is not much study on Hypericum japonicum in foreign countries,and the research groups in China are also very few.The aim of this paper is to study the secondary metabolites and pharmacological activities of Hypericum japonicum in order to provide experimental and theoretical basis for the further development and utilization of this medicinal plant.A new compound Hyperjaponol H（1）and eight known compounds isojacareubin（2）、quercetin（3）、bijaponicaxanthone（4）、saroaspidin A（5）、saroaspidin B（6）、saroaspidin C（7）、sarolactone（8）、sarolactone C（9）,were isolated from petroleum extracts of Hypericum japonicum via silica gel column chromatography（silica gel CC）,reversed-phase（RP）C₁₈MPLC,sephadex LH-20column chromatography,and semi-preparative HPLC.Comprehensive spectra like HRESIMS,NMR,UV,and IR were performed to determine their planar structures.The absolute configuration was established via ECD spectrum.The bioactivity of the compound 1 showed a weak inhibition towards the DNA replication of EB virus in B95-8 cells with the CC₅₀value 25μM.Aspergillus ochraceus,a member of the genus Aspergillus,is rich in ochratoxin.Aspergillus ochraceus is a filamentous fungus with characteristic binary conidia.Traditionally a soil fungus,but it has been adapted to a variety of ecological environments,such as agricultural products,farmed animals and marine species.In our ongoing study,the compounds isolated from Aspergillus ochraceus including sesquiterpenes,alkaloids,sterols and lactones.In recent years,with the continuous development of terrestrial plants,human beings are faced with the contradiction between sustainable development and lack of resources,which makes the exploitation of marine resources into a new research hotspot.Marine microbial metabolites with novel structures and unique activities are one of the important sources of new drugs and lead compounds.In this paper,the secondary metabolites of marine-derived fungi Aspergillus ochraceus,which isolated from Pacific deep sea were studied,which provided an experimental basis for enriching the types of secondary metabolites of the fungus.Eight compounds were isolated from ethyl acetate extracts of Marine-derived fungi Aspergillus ochraceus（MCCC 3A00521）via silica gel column chromatography（silica gel CC）,reversed-phase（RP）C18 MPLC,sephadex LH-20 column chromatography,and semi-preparative HPLC.The structures of these compounds were determined by the analyses of extensive spectroscopic data and identified as nicotinamide（1）、2’-O-methyluridine（2）、cyclo（Ala-Tyr）（3）、Methyl p-hydroxyphenylacetate（4）、diaporthin（5）、2-hydroxy-benzaldehyde（6）、4-hydroxy-benzaldehyde（7）and dioctyl phthalate（8）.Some of these compounds showed weak antitumor activities.