title: Immobilisation of cyclodextrin glucanotransferase from Bacillus circulans ATCC 21783 on purified seasand.
abstract: Cyclodextrin glucanotransferase (CGTase) from Bacillus circulans (ATCC 21783) was immobilised on a silica-based support: purified seasand. Although adsorption of 98% was achieved, considerable desorption was encountered. This problem was minimised by crosslinking the adsorbed enzyme with glutaraldehyde. The immobilised enzyme after crosslinking could be used repeatedly for cyclodextrin (CD) production in a batch process. The activity retention was 80% at the end of the eighth cycle. The immobilised enzyme showed a shift in the pH optimum towards the alkaline side and also an improvement in the pH stability compared to the free enzyme. It catalysed the formation of beta-CD as a major product. A significant amount of alpha-CD production was also observed on prolonged incubation.
authors.affiliation: Food and Fermentation Technology Division, Institute of Chemical Technology, University of Mumbai, Nathalal Parikh Marg, Matunga, Mumbai 400 019, Maharashtra, India.
authors.forename: Jyoti L
authors.initials: JL
authors.lastname: Iyer
authors.forename: Premalatha
authors.initials: P
authors.lastname: Shetty
authors.forename: Jagadish S
authors.initials: JS
authors.lastname: Pai
mesh_terms: D000327:Adsorption; D001407:Bacillus / Q000201:enzymology*; D001709:Biotechnology / Q000379:methods; D003432:Cross-Linking Reagents; D003505:Cyclodextrins / Q000378:metabolism; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000493:pharmacokinetics; D005964:Glucosyltransferases / Q000737:chemistry / Q000493:pharmacokinetics*; D005976:Glutaral; D012822:Silicon Dioxide
chemical_list: D003432:Cross-Linking Reagents; D003505:Cyclodextrins; D004800:Enzymes, Immobilized; D012822:Silicon Dioxide; D005964:Glucosyltransferases; C019963:cyclomaltodextrin glucanotransferase; D005976:Glutaral