USING LOCALLY ISOLATED BACILLUS SUBTILIS ZE2013 IN THE PRODUCTION OF SURFACTIN AND STUDYING SOME OF THE OPTIMAL CONDITIONS FOR ITS PRODUCTION

Abstract

     This study was aimed to using the locally isolated Bacillus subtilis ZE2013 and molecularly identified B. subtilis ZE2013 to produce surfactin,and studying of the optimal it’s conditions, the crude bacteria filtrate have been extracted from culture growth for B. subtilis ZE2013, surfactin was detected by using high performance liquid chromatography (HPLC) technology, the results of HPLC analysis revealed that retention time of the produced surfactin from B. subtilis ZE2013 reached 6.02 min compared to the retention time of the stander surfactin which was 6.09 min, as the concentration of surfactin reached 1588 mg/kg, then detected on the active groups and comparing with the standard surfactin by use the Fourier Transform Infrared Spectroscope(FT-IR),than study the optimal condition for surfactin production, and effectiveness assay determination by use percentage of inhibition of antagonistic activity against selected indicator pathogenic bacteria Escherichia coli, Staphylococcus aureus, Salmonella typhoi, Bacillus cereus. The results showed that Trypticase Soy Broth (TSB), was the optimal culture medium for producing surfactin, inhibitory and the percentage of inhibition against pathogenic bacteria reached 59%, 70%, 65%, and 57% respectively, the glucose was the best carbon source, and tryptophan was the optimal sources of nitrogen. For surfactin production, the percentage of inhibition reached 51%,69%,62%,and 58% ; 59.5%,69.5%,65% and 58%, respectively, and the optimal temperature, was 35°C and the optimal number of ph=7, the percentage of inhibition was 60.5%, 70%, 65.5%, and 58.5%; 59.5%, 69.7%, 65%, and57.5% respectively, and incubation duration 48 h was 60.1%, 70%, 65.2%, and 55% for surfactin production.