NON-REDUCING GLUCIDE-PRODUCING ENZYME, ITS PRODUCTION AND USE

摘要

PURPOSE:To provide a non-reducing glucide-producing enzyme having excellent stability to produce a non-reducing glucide having trehalose structure from a partial decomposition product of redpcing starch, having good sweet taste, absorbable and digestible by oral ingestion and giving a glucide useful as a sweetener, taste-improving agent, etc. CONSTITUTION:The objective new enzyme is produced by culturing a microbial strain [e.g. Rhizobium sp. M-11 (FERM BP-4130)] capable of producing a non- reducing glucide-producing enzyme having trehalose structure from a partial decomposition product of reducing starch. The enzyme has an action to form a non-reducing glucide having trehalose structure on the terminal from a partial decomposition product of one or more kinds of reducing starches having a glucose polymerization degree of >=3. It has a molecular weight of about 76,000-87,000 Dalton measured by SDS-get electrophoresis, an isoelectric point pI of about 3.6-4.6 measured by an ampholinecontaining electrophoresis, optimum temperature of 35-40 deg.C and optimum pH of 6.4-7.2 and is stable at a temperature up to about 35-40 deg.C at pH 7.0 for 60min and stable at pH 5.5-11.0 at 25 deg.C for 16hr.