Productiqn of Cyclodextrin Glycosyltransferase from Bacillus sp.

Abstract

The aim of this work is to study the production of Cyclodextrin Glycosyltransferase(CGTase) from Bacillus sp. The microorganisms were Bacillus circulans(ATCC 9995), Alkalophilic Bacillus sp.(ATCC 21783) and Bacillus sp. B 95 isolatedfrom soil. The major substrate was 1% of soluble starch and 5% of corn steep liquor.The study shows that enzyme production was higher in ATCC 9995 and ATCC 2 17 8 3than B 95. The conversion yield of 5%. of soluble starch to cyclodextrin was 56%within 3 hours, at 40°C with a CGTase from ATCC 9995. From this result, ATCC9995 was selected to further study on the optimum conditions for enzyme production.

Various starches could be used as a substrate for enzyme production. However,enzyme production was faster with tapioca starch as same as corn and soluble starch.Though wheat starch gave the highest enzyme production, the peak was at 72 hours.The optimum initial pH and temperature for enzyme production were 8.0 and 35OCrespectively. In 2.5 litre reactor, dissolved oxygen was critical for enzyme production.Under controlled condition CGTase production was 2250 units/ml in comparison with700 units/ml of oxygen limitation.