Studies On The Chemical Constituents And Bioactivities Of One Plant And Three Higher Fungi

The dissertation comprises five chapters.The studies on the chemical constituents and their bioactivities of one plant species Melodinus henryi,and three higher fungi species,including Tricholoma imbricatum,Fomes fomentarius,and Hericium erinaceus,were introduced in the first four chapters.The last chapter summarized the research progress of diterpenoids peculiar to fungi.A total of 105 compounds,including 20 new ones,were isolated from the above four materials.The classes of these compounds include indole alkaloids,terpenoids,steroids,and so on.Their structures were elucidated on the basis of extensive spectroscopic methods,quantum chemical calculations,and X-ray diffraction analysis.In addition,some compounds were evaluated for their cytotoxicity against human cancer cell lines,and found a series of bioactive compounds.1.Chemical and Bioactive Constituents from M.henryiPlants of the genus Melodinus(Apocynaceae)have been proven to be good sources of monoterpenoid indole alkaloids(MIAs).M.henryi Craib is one species of Apocynaceae existing in Yunnan,China,and its fruits are used in traditional medicine to treat children meningitis and bone fracture.Currently,the chemical investigation on the bark of M.henryi obtained eight new MIAs,together with twenty-seven known ones.Many compounds showed certain cytotoxicities to five human cancer cell lines with IC50 values comparable to those of the positive control.2.Chemical Constituents and Their Cytotoxicities from Mushroom T.imbricatumT.imbricatum(Fr.)P.Kumm.is an ectomycorrhizal fungus with a wide distribution in Sichuan,Shanxi,Gansu,and Qinghai provinces of China.A phytochemical study on the fruiting bodies of T.imbricatum led to the isolation of six new compounds together with 27 known ones.All compounds were evaluated for their cytotoxicities against six human cancer cell lines.3.Chemical Constituents and Their Biological Activities from Mushroom P.fomentariusP.fomentarius(L.ex Fr.)Teng,also called Fomes fomentarius,is an edible macro fungus of the Polyporaceae family.It is a wood-inhabiting fungus usually growing on the side of beech and birch trees,which can cause a white rot by degrading lignin,hemi cellulose,and cellulose of wood.In addition,it has a long history of medicinal usage.For instance,it was applied as hemostatic dressings and bandages during the 18 th and 19 th centuries.In China,this mushroom has been used as a Traditional Chinese Medicine for centuries to treat various diseases such as gastroenteric disorder,hepatocirrhosis,oral ulcer,inflammation,and various cancers.In order to comprehensively understand the chemical constituents of the fungus P.fomentarius,a phytochemical study on its fruiting bodies led to the isolation of four new compounds along with twenty known ones.4.Chemical Constituents and Their Biological Activities from H.erinaceusH.erinaceus(Bull.)Pers.is a mushroom belonging to the family Hericiaceae.It is known as medicine or food in China and Japan.Recently,the chemical investigations on this mushroom resulted in the isolation of novel molecules with versatile bioactivities,among which isoindolinones and cyathane-type diterpenoids were conspicuous constituents.In the current study,two new compounds and eleven known ones were obtained from the rice fermentation culture of H.erinaceus.5.Diterpenes Peculiar to Fungi: Chemistry,Bioactivities,Synthesis(2010–2020)Fungi have traditionally been a very rewarding source of biologically active natural products,while diterpenoids from fungi,often represent unique carbon skeletons and diverse bio-functions.The abundance of novel skeletons,biological activities,and biosynthetic pathways presents new opportunities for drug discovery,genome mining,and enzymology.In addition,diterpenoids peculiar to fungi also reveal the possibility of different biological evolution,although they have similar biosynthetic pathways.This review gives an overview of the isolation,structure,biological activities,evolution,chemical,and biosynthesis of diterpenoids peculiar to fungi in recent ten years.