| 摘要 |
PROBLEM TO BE SOLVED: To efficiently obtain an enzyme such as mannase, etc., useful for bleaching, etc., of pulp without using chlorine-based chemicals by culturing bacteria capable of producing the enzyme in a neutral medium, then culturing in an alkaline medium by changing the medium and harvesting the enzyme. SOLUTION: This production process of an enzyme capable of bleaching pulp without using chlorine-based chemicals comprises inoculating bacteria (e.g. Bacillus lentus, etc.), having activity for producing the enzyme such as mannase having activity in an alkaline region to a neutral medium; producing a precultured solution by culturing under shaking at 30 deg.C for 1 day; adding the precultured solution to an liquid culture medium; culturing it under shaking at 30 deg.C for 16 hours in a neutral condition; adding 1 mol Na2 CO3 solution to adjust to pH 10.5; culturing under shaking for further 20 hours in an alkaline condition; centrifuging the cultured medium; and harvesting a supernatant which is concentrated under reduced pressure, dialyzed, salted out, ultrafiltered and finally lyophilized. |
