Isolation, Identification And Material Analysis Of Culturable Fungi From Forest Litter In Daxing'an Mountains

This study isolates culturable fungus from forest litter in the Great Khingan Range,as well as discover the biological activities and antimicrobial metabolites of those culturable fungus,in order to provide fungal stains for further development and utilization of litter fungal resources.This study isolated and cultured fungi from forest litter samples by dilution coating plate method.By the methods of molecular biology and morphology,this study was to find the culturable and undescribed fungi.Then their antimicrobial,antioxidant,and cellulose degradation activities were investigated and metabolites from fungi with the antimicrobial activities were separated and identified.This study isolated and cultured 70 fungal strains that were preliminarily identified by molecular biology as 3 phyla,9 classes,14 orders,22 families and 57 taxa.Twentyone fungal strains whose similarities of Internal Transcribed Spacer(ITS)sequences were less than 98.5%,which were identified as target fungi.In this study,it uses 4 type different medium for a little fermentation and prepare extract to screen the antimicrobial and antioxidant activities.It tested the antimicrobial activity 5 microorganisms by perforating agent diffusion method,and the antioxidant activities were tested by free radical scavenging method.Of them,17 strains showed antimicrobial activities and 8 strains showed antioxidant activities.Four fungal strains showed cellulose-degrading activity by Congo red staining method.SGSF409,SGSF450 and SGSF449 were selected for the further separation of metabolites as target fungal strains.SGSF449 was identified as a suspected new species by morphological and phylogenetic analysis.In this study,SGSF450,SGSF409 and SGSF449 were enlarged fermented volume.Four compounds were isolated and identified by different chromatography.Three compounds were determined as 6,9-epoxy-ergosta-7,22-diene-3-ol(SGSF409B),henicos-9-enoic acid(SGSF450A)and 4,6,8-trihydroxy-7-methoxy-3-methyldihydroisocoumarin(SGSF449A),respectively,there two compounds were tested minimal inhibitory concentration.There are abundant fungal resources in the forest litter in the Great Khingan Range.In this study,there were 17 fungal strains with antimicrobial activities,8 strains with antioxidant activities,4 strains with cellulase degradation activities and 3 monomeric compounds were separated and identified.It laid a foundation for the further development and utilization of forest-litter fungi from the Great Khingan Range.