Inhibition Mechanism of Ethyl Acetate Extract of Schizophyllum commune on Fusarium oxysporum
Fusarium oxysporum is a major pathogen causing root rot of Panax ginseng.To investigate the antifungal mechanism of ethyl acetate extract from Schizophyllum commune against Fusarium oxysporum,the pathogen was cultured with the extract,and then observed for hyphal growth,spore germination,and microscopic hyphal morphology;determined for cell membrane permeability by measuring electrical conductivity and nucleic acid content;and also determined for the degree of membrane lipid peroxidation by measuring malondialdehyde(MDA)content,hydrogen peroxide content,superoxide dismutase activity,peroxidase activity and catalase activity.The results showed that the S.commune ethyl acetate extract significantly inhibited the hyphal growth and spore germination of F.oxysporum,with an inhibition rate of 56.75％ after cultivation at the minimum inhibitory mass concentration(5.00 mg·mL-1)for 7 d,and an inhibition rate of 100％ after cultivation at the minimum bactericidal mass concentration(20.00 mg·mL-1)for 7 d.The ethyl acetate extract caused F.oxysporum hyphae to shrivel,and increased cell membrane permeability and leakage of cellular contents.Compared with the blank control,5.00 mg·mL-1(minimum inhibitory mass concentration)of the ethyl acetate extract significantly increased the conductivity and nucleic acid content of F.oxysporum at 10 h,and the contents of MDA and H2O2 in hyphae after 24 h.The activities of POD,CAT and SOD initially increased and then decreased,peaking at 12 h.In summary,the ethyl acetate extract of S.commune induced production of excessive reactive oxygen species and exacerbated membrane lipid peroxidation to cause membrane damage and loss of cellular contents,which destroyed the fungal defense system and reduced the content of protective enzymes,and thus significantly inhibited the hyphal growth and spore germination of F.oxysporum.
NETL
NSTL
万方数据
