CAJ | 학술논문

以产β-甘露聚糖酶的植物内生菌Bacillus subtilis UD-20为研究对象，通过对产酶条件优化得出最佳产酶方案为：魔芋精粉30 g/L，蛋白胨3 g/L ，硝酸铵3 g/L，氯化钙3.0 mmol/L，氯化镁2.0 mmol/L，氯化钡0.2 mmol/L，2%的接种量发酵培养72 h，酶活高达213.6 U/mL，是优化前的2.4倍，通过补料发酵使酶活提高到275.1 U/mL，较补料前提高了34%。另外，静置培养也使酶活得到了很大提高。较低的Km（10.9 mg/mL）和较高Vmax（9960.2 U/mL）显示该酶的具有较强的底物特异性，以葡甘露聚糖为底物时的酶活高达6116.6 U/mL，是酶解槐豆胶的22.2倍，酶解瓜尔豆胶的28.2倍。
이산β-감로취당매적식물내생균Bacillus subtilis UD-20위연구대상，통과대산매조건우화득출최가산매방안위：마우정분30 g/L，단백동3 g/L ，초산안3 g/L，록화개3.0 mmol/L，록화미2.0 mmol/L，록화패0.2 mmol/L，2%적접충량발효배양72 h，매활고체213.6 U/mL，시우화전적2.4배，통과보료발효사매활제고도275.1 U/mL，교보료전제고료34%。령외，정치배양야사매활득도료흔대제고。교저적Km（10.9 mg/mL）화교고Vmax（9960.2 U/mL）현시해매적구유교강적저물특이성，이포감로취당위저물시적매활고체6116.6 U/mL，시매해괴두효적22.2배，매해과이두효적28.2배。
Bacillus subtilis UD-20 is an endophytic bacteria for β-mannanase production. The optimum of fermentation conditions was preliminary determined as follows: konjac glucomannan 30 g/L, peptone 3 g/L, NH4NO3 3 g/L, CaCl2 2.0 mmol/L, MgCl2 2.0 mmol/L, BaCl2 0.2 mmol/L, inoculation volume of 2%incubation for 72 h, the β-mannanase activity (213.6 U/mL) was got and 2.4-fold of the original. the fed-batch fermentation activity is 275.1 U/mL and increased 34 % compared with the original. In addition , The static culture activity is better than the conventional fermentation. The lower Km value (10.9 mg/mL) and higher Vmax value (9 960.2 U/mL) showed that theβ-mannanase from endophytic bacteria Bacillus subtilis UD-20 have Strong substrate specificity. Theβ-mannanase showed the highest activity(6 116.6 U/mL) on glucomannan, which was the best substrate, 22.2-fold of locust bean gum and 28.2-fold of guar gum.