Chemical Investigation Of Secondary Metabolites From A Fungus Cladosporium Sp.JNU17DTH12-9-01

Fungi are important sources of structural diversity and active natural products.Cladosporium sp.are widely distributed and one of the largest fungi.They can produce secondary metabolites with diverse structures,such as alkaloids,lactones,quinones and steroids.The secondary metabolites of Cladosporium sp.JNU17DTH12-9-01 were found to have abundant chemical constituents and structural diversity by chemical screening method of HPLC-DAD-MS.In this paper,large-scale fermentation of the strain was carried out.Twenty-four compounds were separated by chromatographic methods,such as silica gel column chromatography,ODS column chromatography,gel column chromatography and high performance liquid chromatography.Their structures were identified by UV,IR,MS,NMR and ECD.These compounds include two indole diterpenoids(1-2),six cladosporols(3-8),six naphthalopyranones(9-14),five sterols(15-19),and five other compounds(20-24),including one new compound,fifteen compounds isolated from Cladosporium for the first time.In addition,compounds 1-24 were evaluated for their antimicrobial activities against [Candida albicans FIM709,Aspergillus Niger R330,Staphylococcus aureus 209 P,Escherichia coli ATCC0111].The results showed that some compounds showed antimicrobial activities.Among them,compound 1 showed anti-Staphylococcus aureus activities(MIC: 4 μg/m L)and anti-Candida albicans activities(MIC: 16 μg/m L).Meanwhile,compounds 1-24 were tested for their activities of anti-acetylcholinesterase and DPPH radical scavenging.and they didn’t show activities.In this paper,indole diterpenoid alkaloids(1-2)were isolated from Cladosporium sp.for the first time.Compound 1 is a new compound named cladosporine A.