Antifungal Activities of Actinomycetes Isolated from a Sample of Iraqi Soils


Background & objective: This work aimed to isolate and identify naturally actinomycetes from different samples of Iraqi soils producing antifungal activity on different culture media.Materials & Methods: Twelve soil samples were collected from different sites of Baghdad (Jadria, Yarmouk, and Kadisa) in Iraq at summer season 2007. The actinomycetes were isolated on Starch – Casein – nitrate at different incubation temperatures and screened for antifungal activity on modified Bennett agar , Yeast extract - malt extract agar and Gaza agar against fungi including yeast (Candida albicans) and molds (Fusarium, Penicillum). All isolates of actinomycetes were tested for sensitivity to commonly used antibacterial drugs employing Kirby – Bauer method. Morphological characterization of these isolates were studied according to ISP (International streptomyces project) media which included color of aerial, substrate mycelium, soluble pigments and their PH sensitivity, form of sporophroe. Cell wall analysis was carried out for these isolates. Results: During a search for antifungal activity, either two actinomycetes strain were isolated from different samples of Iraqi soils. Twenty – Two isolates showed strong activity against yeast, & molds. All isolates were found to be belonging to genus streptomyces. Modified Bennett agar is good medium for antibiotic production at 30Co. These isolate were sensitive to all antibacterial drugs in this study. Their cell wall consists of Pepptidoglycan.Conclusion: The metabolite from Iraqi actinomycetes was active against yeast & molds. However, this needs further investigation using purified form of the active component of antibiotics from local isolates. Key words: Actinomycetes, antifungal activity Antibiotic.