Abstract: Chitinase with the following physico-chemical properties 1 to 6: 1. action: random cutting of the &bgr;-1,4 bond of chitin to generate the tetramer and dimer of Nacetylglucosamine; 2. optimum pH: 6.5 to 10.4; 3. stable pH: 7.0 to 9.0; 4. optimum temperature: 37° C.; 5. active temperature range: 4 to 60° C.; and 6. thermal stability: 60% or more of the initial activity as retained even after heating at 40° C. and pH 8.0 for 30 minutes; and a method for producing chitinase, comprising culturing a chitinase-generating bacterium reacting with chitin to generate the N-acetylglucosamine oligomer and collecting chitinase from the culture.

Abstract: A process for producing N-acetylglucosamine-6-phosphate deacetylase comprising incubating a microorganism which belongs to the marine psychrotrophic bacterium Vibrio sp. and recovering the N-acetylglucosamine-6-phosphate deacetylase from the culture thus obtained; N-acetylglucosamine-6-phosphate deacetylase; and a bacterium belonging to the marine psychrotrophic bacterium Vibrio sp.

Abstract: A process for producing N-acetyl-D-glucosamine deacetylase which comprises incubating a microorganism belonging to the genus Alteromonas and recovering N-acetyl-D-glucosamine deacetylase from the culture thus obtained.

Abstract: A glucosamine 6-phosphate deaminase having specific physicochemical properties. A process for producing the glucosamine 6-phosphate deaminase which comprises incubating a microorganism belonging to the genus Vibrio and harvesting the glucosamine 6-phosphate deaminase from the culture thus obtained.

Abstract: A process for producing deacetylase which comprises incubating a deacetylase-producing bacterium belonging to Vibrio cholerae in a IFO 15429 culture medium containing a carbon source, a nitrogen source, an inorganic salt and an inducer for producing the deacetylase and isolating the deacetylase from cells separated from said culture medium.

Abstract: A process for preparing a low-molecular weight chitosan which comprises adding chitosan to water containing a monobasic acid to prepare an intimate chitosan-water mixture and treating said mixture with cellulase.

Abstract: A cellulosic material is saccharified by cellulases and the resulting saccharified solution is acidified. Subsequently chitosan and/or partially deacetylated chitin are dissolved therein and the obtained solution is alkalified. Thus the cellulases are absorbed by the chitosan and/or partially deacetylated chitin. Further a cellulosic material is saccharified by at least one cellulase originating from a fungus belonging to the genus Aspergillus and at least either chitosan and/or partially deacetylated chitin are added to the resulting saccharified solution to thereby adsorb the cellulase by the chitosan and/or partially deacetylated chitin.

Abstract: A process for the saccharification of celluloses is provided. More particularly, a solution obtained after the degradative saccharification of cellulosic materials with cellulases is separated into a liquid portion containing saccharides and a solid matter. Cellulases are recovered from said liquid portion containing saccharides, while said solid matter is treated with an aqueous pH-buffered solution, or an aqueous solution, alcoholic aqueous solution or aqueous pH-buffered solution of polysaccharides or oligosaccharides, or aqueous or aqueous pH-buffered solution of alcohols to recover the cellulases in the solid matter. With the use of this solid matter, newly added cellulosic materials are degradatively saccharified in an aqueous solution or the above-mentioned solutions.

Abstract: There are provided N-acetyl-D-glucosamine deacetylase capable of hydrolyzing acetamide group of N-acetyl-D-glucosamine to produce D-glucosamine and acetic acid, which has the following physicochemical properties:(1) Substrate specificity: N-acetyl-D-glucosamine monomer, not the oligomer or polymer thereof;(2) Optimal pH: 7.8-8.2 at 37.degree. C.;(3) Stable pH: 6.0-9.0 at 45.degree. C.;(4) Optimal temperature: 28.degree.-39.degree. C.;(5) Molecular weight: 70,000-200,000 as determined using TSK-gel G-3000 SW column,and a process for preparing the same using a microorganism belonging to Vibrio sp.