Cyclodextrin production from amaranth starch by cyclodextrin glycosyltransferase produced by Paenibacillus macerans CCM 2012

Abstract

Cyclodextrins (CDs) are synthesised by bacterial extracellular enzym cyclodextrin glycosyltransferase (CGTase, E.C. 2.4.1.19) from starch or starch derivatives. The production of α-, β-, and γ-CDs by CGTase from Paenibacillus mace-rans CCM 2012 was studied in regard to the effect of the starch source (amaranth, maize) on the yield of CDs. CGTase was produced by a 3-day sterile cultivation in the laboratory Bench-top fermentor BiostatB under aerobic conditions. CGTase was partially purified by ammonium sulfate precipitation at 60% saturation. Electrophoretic analysis (SDS-PAGE) of the isolated CGTase enzyme was carried out according to the method by Laemmli (1970), the apparent molecular weight was in the range from 105 kDa to 114 kDa. All the commercially important α-, β-, and γ-CDs were detected chromatographically after the hydrolysis of the maize and amaranth (Amaranthus cruentus) starches with the isolated enzyme. The amaranth starch appears to be an excellent substrate for CDs production because of the high dispersibility, high starch-granule susceptibility to amylases, and the exceptionally high amylopectin content.