earticle

영어

A carboxymethylcellulose (CMC) hydrolyzing microorganism was isolated from seawater, identified as Bacillus licheniformis by analyses of 16S rDNA sequences, and designated B. licheniformis LBH-52. Rice hulls and ammonium nitrate were one of the best combinations of carbon and nitrogen sources for the production of CMCase by B. lincheniformis LBH-52. Based on intuitive analysis and statistical calculations using data from an L25 (54) orthogonal array experiment with four factors - rice hulls and ammonium nitrate as carbon and nitrogen sources, initial pH of the medium, and temperature – and five level of each factor, optimal concentrations of rice hulls and ammonium nitrate, initial pH of the medium, and temperature for cell growth of B. lincheniformis LBH-52 were found to be 75.0 and 2.0 g/L, 7.0, and 30℃, respectively,
whereas those for the production of CMCase were 30.0 and 0.5 g/L, 7.0 and 35℃, respectively. According to R values calculated from results of the orthogonal array experiment, the most important factor for cell growth of B. lincheniformis LBH-52 was rice hulls, whereas temperature was found to be the most important factor for the production of CMCase. The highest production of CMCase by B. lichemiformis LBH-52 was about 120 U/mL under optimized conditions in this study.