THE EFFECT OF SOME FUNGICIDES AND TOTAL SAPONIN ON SELECTED CHEMICAL COMPONENTS OF CERTAIN FUNGI

Abstract

The present study aimed to evaluate the effect of total saponin (TS) extracted from mulberry root bark and some fungicides using EC50 for each on the chemical components (total soluble sugars, free amino acids or total protein) and some enzymes (amylase, peroxidase, catalase, polyphenol oxidase (PPO), protease, polygalacturonase (PG), polymethyl esterase (PME) and cellulase of certain fungi i.e. Al. alternata, B. cinerea, F. oxysporum, R. solani and S. rolfsii. Electrophoresis studies were carried out on selected fungi grown in liquid media treated with total saponin at EC50 comparing with untreated media. Results concluded that, TS and carboxin fungicide decreased the biochemical components F. oxysporum, R. solani and S. rolfsii. Thiophanate-methyl and TS decreased total soluble sugars, free amino acids and total protein. The inhibition percentage of free amino acids and total protein in B. cinerea treated with thiophanate-methyl were 37.0 and 43.1, respectively, compared with the untreated controls. Amylase activity produced by B. cinerea treated with TS or thiophanate-methyl was decreased comparing with the untreated control. PPO activity was completely inhibited in B. cinerea when liquid media was treated with thiophanate-methyl. The reduction of catalase and protease activities was recorded in B. cinerea treated with TS or thiophanate-methyl and compared with the untreated control. Thiophanate-methyl induced a significant (p < 0.01) decrease in peroxidase activity produced by B. cinerea comparing with the untreatment, while the treatment with TS induced non significant decrease in peroxidase activity compared with the untreated control. Adding TS to liquid medium was more effective than thiophanate-methyl in reducing cellulase and PG activities produced by B. cinerea. Also, the treatment of liquid media with TS or thiophanate-methyl caused highly inhibition in PME activity, which reached 62.3 and 65.4%, respectively. The reduction of free amino acids and total protein were observed in Al. alternata treated with TS or copper sulfate, which recorded 24.3, 32.0% and 29.9, 46.2%, respectively, of that produced in untreated media. Amylase activity produced by Al. alternata was completely inhibited other treatment with TS, while copper sulfate caused significant (p < 0.001) decrease in this enzyme compared to the untreated control. In contract, TS expressed non significant decrease in PPO activity, but, copper sulfate expressed a significant (p < 0.01) decrease in PPO activity produced by Al. alternata. TS and copper sulfate caused greatly decrease and significant (p < 0.01) protease activity comparing with the untreated control. The inhibition of protease activity for treated Al. alternata recorded 48.8 and 53.5%, respectively. TS induced non significant decrease in preoxidase activity, while, copper sulfate caused a low significant (p < 0.05) decrease in the enzyme activity produced by Al. alternata compared to the untreatment. In contract, TS was more effective than copper sulfate on the reduction of cellulase and PG activities. The electrophoresis studies showed that S. rolfsii was more sensitive to TS comparing with the other selected fungi.