The Effect of Cultural Conditions on the Variations of SOD,CAT and GSH-Px Activities and LPO Levels in the Filamentous Fungus Fusarium equiseti

摘要

The changes in the activity of cellular detoxifying defence enzymes such as SOD,CAT and GSH-Px against superoxide anion radical and hydrogen peroxide,and in LPO levels in the filamentous fungus.Fusarium equiseti were measured under growth condition.Experiments were performed comparing changes in glycerol and saccharose(5-25 g/L)as carbon sources,and in glycine,peptone(5-35 g/L)as nitrogen sources in an AFM medium.While SOD activities correlate well with respect to the increase in the glycerol concentration(r = 0.437,p < 0.001),CAT activities showed negative correlation(r = -0.663,p < 0.001).The increase in SOD and CAT activities of F.eqmseti correlated with increases in saccharose concentration.When glycerol and saccharose were used as carbon sources,the maximum SOD,CAT and GSH-Px enzymes activities and the minimum LPO level were determined in the medium containing 15 g/L of saccharose on the 12~(th)day at 66.61,182.79,1.045 lU/mg and 1.41 nmol MDA/ gr wet weight,respectively.The effects of peptone and glycine as nitrogen sources were also investigated:53.4% and 48.03% decreases were observed in the SOD and CAT activities of F.equiseti in the presence of 10 g/L of peptone in the culture medium.The presence of 15 g/L of glycine caused 5.30% and 69.90% decreases in the SOD and CAT activities in comparison to the presence of 15 g/L of saccharose,respectively.On the other hand,LPO levels increased in proportion to the decrease in antioxidant enzyme activities in glycine and peptone supplemented media.