Study On The Isolation,Screening And Bioactivities Of Two Endophytic Fungus

Endophytic fungus refers to a type of fungus that lives normally inside the host and does not have an adverse effect on the host.Endophytic fungi can produce a large number of biologically active secondary metabolites,which are very important in the development and application of medicinal products.At present,there are many research reports on Areca catechu L,but there are few reports on the secondary generation products of its endophytic fungi.Therefore,in this paper,two endophytic fungi were selected through chemical screening to obtain target endophytic fungi with rich structural types and capable of large-scale fermentation.The secondary metabolites of endophytic fungi were separated and purified.Different spectral data and Mosher reaction were used to identify their structures,and the separation and identification The biological activity of the secondary metabolites is determined,and the active molecules are found,which provides a theoretical basis for analyzing its metabolic relationship with the host and mining its medicinal value.In this paper,a total of 17 compounds are classified from the secondary metabolites of the betel nut endophytic fungus G10（Trichoderma asperellum）,including 7 new acetal compounds and 1 new propionate（8）named Trichoasperellin A-D（5-8）;trichoasperellin E（11）;trichoasperellin F-G（14-15）;Trichoasperellin H（17）,and 9 known compounds,which are 4-hydroxysalicylin（1）;5-carboxyptterin（2）;4S,5S,6Z,8E-5-hydroxydeca-6,8-dien-4-olide（3）;2-（4-hydroxyphenyl）acetic acid 4-hydroxyphenyl ethyl ester（4）;monaspilosin（9）;2-（4-hydroxyphenyl）ethylacetate（10）;1-phenoxyheptane-3,5-dione（12）;2-phenyl phenethyl acetate（13）;pichiacin B（16）.Two new indole diterpenoids were isolated and identified from the endophytic fungus KFD 28（Penicillium sp.）,named epipaxilline（18）and penerpene J（19）.Bacteriostatic experiments,acetylcholinesterase inhibitory activity,α-glucosidase inhibitory activity and anti-inflammatory activity were performed on 18 compounds isolated from endophytic fungus G10.Compounds4/9/11 and 15 have anti-inflammatory activity,and the inhibition rate reached 76.23%、68.19%、85.08%and 69.13%,none of the others have the measured activity.The protein tyrosine phosphatase inhibitory activity（PTP1B,TCPTP,PTPsigma,VHR）and acetylcholinesterase inhibitory activity of the two compounds 18 and 19 isolated from the endophytic fungus KFD 28 were determined,and it was found that these two compounds have PTP1B/TCPTP/PTPsigma and VHR inhibitory activities,with an IC₅₀ value of 31.75μM/9.5μM（PTP1B）and>40μM/14.7μM（TCPTP）and>40μM/>40μM（PTPsigma）and>40μM/>40μM（VHR）,but do not have acetylcholinesterase inhibitory activity.