Identification And Primary Study On Antimicrobial Activity Of Fungal Endophytes Of Glycyrrhiza Uralensis From Inner Mongolia

Fifty-four endophytic fungus stains were isolated from roots,stems of Glycyrrhiza uralensis,44 from roots and 10 from stems.Cultured at 28℃,the number of strain were 24,18 from roots and 6from stems.Cultured at 20℃,26from roots and 4 from stems.Twenty active strains were obtained by the inhibitory activity screening,which ratio in total stains was 37.07%.One of the strains,dG9-1 showed the best wide-spectrum which have the activity against gram-positive bacteria,Staphylococcus aureus,Bacillus subtilis and fungus,and was only stain against gram-negative bacteria.The cultrue of dG9-1 also had the activity against TMVand HepG2 cancer cells.The endophytic fungus was classified by morphological traits and internal transcribed spacer(ITS) rRNA gene sequence analysis.Its ITS rDNA sequences was 99.46%identical to Penicillium griseofulvum.The culture of dG9-1still had antimicrobial activities at 121℃for 30 min and pH1.0-9.0.The activty products in culutre could not dissolved in petroleum ether,aether, chlorofor and little dissolved in n-butanol but completely dissolved in acetic ether.The saponin reaction and a-naphthol reaction of the culture of dG9-1 was active which proved that it contained saponin or triterpenoid saponin.There was flavonoids in the zymotic fluid by flavonoids color reaction.When the developing agent was n-butanol: glacial acetic acid:H₂O(4:1:2,V/V/V),the glycyrrhizic acid could be detected existing in the culture of dG9-1 though the method of TLC(Rf=0.497) and be further proved by HPLC.