초록
Quantitative differentiation of the inoculated Promicromonospora sp MARS and indigenous microbial flora of rice straw is described using ERIC-PCR during the production of xylanase in non sterile solid state fermentation (NS-SSF) to reduce the cost of enzyme production. Under non-sterile solid state fermentation with rice straw, Promicromonospora sp MARS produced 85.0IU/g of xylanase. DNA fingerprints of unknown bacterial isolates obtained on BHA+xylan exactly matched with that of Promicromonospora sp MARS. Using PCR based enumeration; population of Promicromonospora sp MARS was 67.5x10<SUP>5</SUP>cfu/g after 48h which increased to 23x10<SUP>6</SUP>cfu/g after 96h which coincided with the maximum xylanase activity as compared to 14x10<SUP>4</SUP>cfu/g in control after 96h. Under submerged fermentation (SmF), after 48h, Promicromonospora sp MARS produced maximum xylanase (42.2IU/ml) using rice straw as substrate followed by 19.9 and 20.4IU/ml when Promicromonospora sp MARS was grown on rice husk and wheat straw, respectively. Optimum pH and temperature of the crude xylanase were 8.0 and 65<SUP>o</SUP>C. Crude enzyme was 95% stable for 180min of incubation at pH 8.0 and was stable at 65<SUP>o</SUP>C for 240min.