Isolation And Identification Of The Antifungal Activity Compounds From The Metabolites Of Endophytic Fungi G4 In Camptotheca Acuminata

The natural active products are important treasure-house source to develop biopesticide and lead compound.As the particular living environment of plant endophytic fungi,they could product novel structure and well biological activity secondary metabolites,these metabolites have great potentialities become biopesticide and already gaining attention for more and more researchers.Hence,the paper utilized a strain of Chaetomium globosum G4 that isolated from camptotheca acuminata in previous study,use pathogenic fungi of Cytospora mandshurica to evaluate it's antifungal activity to explore it's secondary metabolites,obtained 3 compounds in total,and then evaluated the antifungal activity of them.as follew are major studies:Researched different days'fermentation liquor's antifungal rate for Cytospora mandshurica of G4,and confirmed 12 days is the best fermentation period.Compared different extractions extract fermentation liquor and mycelium,the result confirmed that the antifungal activity compounds were mainly exist in fermentation liquor and the trichloromethane is the best extraction.Determination the antifungal rate of fermentation liquor and extractum from fermentation liquor that was extracted by trichloromethane,the EC₅₀0 of antifungal rate were 14169.35?g/mLand 0.1928?g/mL.In addition,we attermpted to use fermentation tank to ferment the endophytic fungi of G4,the result is the antifungal rate of fermentation tank's fermentation only resch the antifungal rate of flask fermentation's 67.8%.We had fermentation 115L G4 in total,and obtained 2.669 g extractum.Through slica column chromatography preliminary extractum,combined the technology of HPLC with TLC,and evaluated the antifungal rate of each fraction,then co collect the similarity fraction to further purified by p-HPLC,isolated three indole alkiods,Chaetoglobosin C,Chaetoglobosin U and Chaetoglobosin V.All of them are belong to chaetoglobosins family,evaluated their antifungal rate to Cytospora mandshurica,Chaetoglobosin C and U have the inhibiting activity were 19.81%and 37.11%in 5?g/mL,and Chaetoglobosin V was12.79%in 10?g/mL.The datas show that 3 compounds'antifungal rate to Cytospora mandshurica not as good as mixed component's activity,the antifungal activity appeared lose phenomenon.We found that the coumpounds exist structure change druing the prosess in p-HPLC after analyze it's high performance liquid chromatography figure.Combine already obtained 3 compounds'structure,we suspected that the target activity compounds may chaetoglobosins,and it can prone to structure transformation.In summay,there alkiods isolated from the C.Globosum in camptotheca acuminata and they had antimicrobial bioactivity on pathogenic fungi of Cytospora mandshurica.