Background and aims: In this study was carried out solid substrate fermentation to evaluate a variety of solid substrates in the production of asparaginase enzyme isolated strain of Bacillus from LAKAN region of Gilan.

Methods: In this  experimental study, the screening of bacteria producing L-asparaginase of was used by M9 medium. For screening of different substrates in the solid bed, rice bran, rice stalks, wheat bran and wheat stalks as carbon sources and yeast extract, peptone, asparagine and tryptone as nitrogen sources were used. To optimize the culture medium and the effect of carbon and nitrogen sources on the production of enzymes asparginase using Plackett-Burman total of 12 experiments were designed on two levels. Then, the enzyme production was evaluated by changing the factors affecting the production in a variety of solid substrates.

Results: As the best solid substrate, rice bran and the best source of nitrogen, asparagine showed the greatest effect on enzyme production. The best production of the enzyme in 1.5% (w/w) rice bran concentration and 0.5% (w/w) asparagine concentration was achieved 69.24 U/g in 30ºC for 72h.

Conclusion: In the current study, the rate of enzyme production increased substantially using rice bran as carbon source in the solid state fermentation after optimizations conditions rather than not to optimized conditions.