ENHANCEMENT OF ENZYMATIC PRODUCTION OF CYCLODEXTRINS BY ORGANIC-SOLVENTS

Abstract

A strain of Bacillus sp.BE101 was isolated from soil and used to obtain the cyclodextrin glycosyltransferase (E.C.3.2.1.19, CGTase). Cyclodextrin glycosyltransferase from Bacillus sp. BE101 synthesized mainly beta-cyclodextrin from soluble starch; the composition of alpha-, beta-, and gamma-cyclodextrin was 1 : 7 : 2. The optimum conditions for CGTase activity were pH 6.0-6.5 and temperature 45-degrees-C. An increase in cyclodextrin production by organic solvents such as acetone, propanol, and ethanol was observed. The maximum increase was observed at 10% ethanol, and the enhancement of production yield was about 100%. Studies on the cause of the increase in production yield of cyclodextrins by ethanol were carried out. It seemed that enhancement of the yield by ethanol was due to the increase in hydrolysis of starch by CGTase in the presence of ethanol.