Isolation of bacteria capable of producing alginate-degrading enzyme from natural environment.

A search was undertaken to find bacteria with a usefully high productivity of alginate-degrading enzyme. By an aerobic screening method, 26 bacteria with the productivity were obtained from the sea, whereas none from the freshwater and the land. The enzyme productivities of all the isolates were compared to one another. Special attention was given to the production of large quantity of the enzyme by the two strains of bacteria (strains A1-9 and A1-128). A1-9 strain produced an extracellular enzyme when grown in no alginate-adding medium. On the contrary, A1-128 strain produced the enzyme when grown in 0.3-0.5% alginate-adding medium.The enzyme of A1-9 strain increased remarkably reducing sugar from the substrate, and that of A1-128 strain decreased the viscosity of the substrate. Both enzymes were activated by the addition of 0.3M NaCl, and showed an activity of alginate lyase.Identification according to the Bergey's Manual of Systematic Bacteriology permitted assignment of the two strains to the genus Vibrio, and they may represent profitable sources of alginatedegrading enzyme.