الفهرس 
Characterization of some extracted microbial metabolites applied in biological control programs
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Abstract
The associated fungi were isolated from the roots and fruits of tomato plants from two Governorates i.e. Qaliubiya and Banisweif.The isolated fungi were identified as follows, F. solani, F. oxyspoum, F. semitectum, R. solani, S. rolfsii and B. cinerea. The efficacy of three bacterial strains used in biological control were tested against phytopathogenic fungi, these strains were P. fluorescens, S. marcescens and B. velezensis. Bacterial strains effectively inhibited the mycelium growth of all fungi in dual culture test. Also, the culture filtrate at different concentrations reduced the mycelium growth except in case of B. velezensis and P. fluorescens against R. solani and S. rolfsii.The culture filtrate at EC50 concentration was effective in reducing the total contents of soluble sugars, free amino acids, total proteins and enzymes activities produced by the phytopathogenic fungi. Some compounds were extracted from the filtration of bacterial cultures that showed the highest efficacy in the results against the phytopathogenic fungi.The culture filtrate of P. fluorescens was extracted with ethyl acetate solvent and tested for its efficacy against the phytopathogenic fungi. The crude extract from P. fluorescens at 100 mg ml-1 completely inhibited F. oxysporum and S. rolfsii and purified by column puriflash and re-tested for antifungal activity. The major compound in the crude extract was characterized by TLC, mass spectrometry and FTIR. All analysis confirms that the antifungal compound in the crude extract is pyrrolnitrin.The prodigiosin pigment was also extracted from S. marcescens and purified by the column puriflash and also characterized by TLC, mass spectrometry and FTIR and the pigment was evaluated against pathogenic fungi at different concentrations and the most influenced fungi were the fungi Botrytis cinerea followed by Rhizoctonia solani