Optimization of antifungal production from a novel strain Streptomyces sp. TKJ2 using response surface methodology

A newly filamentous bacteria was recovered from Tikjda forest soil (Algeria) for its high antifungal activity against various pathogenic and phytopathogenic fungi. The nucleotide sequence of the 16S rRNA gene (1454 pb) of Streptomyces sp. TKJ2 exhibited close similarity (99 %) with other Streptomyces 16S rRNA genes. Response surface methodology (RSM) was employed for optimizing this production. Three nutritional variables namely concentration of carbon source (starch), nitrogen source (casein), and NaCl were selected for the production of antifungal in submerged fermentation. Starch, casein, and NaCl were found to influence antifungal production significantly. These variables were selected for further optimization studies using a Box–Behnken design at three levels in 15 experiments using full factorial design. The statistical optimization by RSM to enhance the yield of antifungal production by Streptomyces sp. TKJ2 resulted that starch and NaCl increase, respectively, 13.05 g/l instead of 10 g/l and 2.54 g/l instead of 2 g/l. While casein decrease 0.2 g/l instead of 0.3 g/l. The present study has proved that RSM could be used as a valuable and dependable tool for the optimization of antifungal production from actinomycetes.