Integrated immobilized cell reactor-adsorption system for beta-cyclodextrin production: a model study using PVA-cryogel entrapped Bacillus agaradhaerens cells.
Production of cyclodextrins (CDs) by immobilized cells of the alkaliphilic Bacillus agaradhaerens LS-3C with integrated product recovery was studied. The microorganism was entrapped in polyvinyl alcohol-cryogel beads and used as a convenient source of immobilized cyclodextrin glycosyltransferase (CGTase). On activation by incubation in the cultivation medium containing 1% (w/v) starch, the entrapped cells multiplied and secreted CGTase with an activity of 2-3 mg beta-cyclodextrin h(-1) g(-1) beads. The immobilized biocatalyst exhibited maximum activity at pH 9 and 50 degrees C, and formed cyclodextrins comprising 92-94% beta-CD and remaining alpha-CD. The cyclodextrin product from the immobilized cell bioreactor was continuously recovered by adsorption to Amberlite XAD-4 in a recycle batch mode. The product adsorption was facilitated at low temperature while hot water was used for elution.
Department of Biotechnology, Center for Chemistry & Chemical Engineering, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden.
Rita F
RF
Martins
Fatima M
FM
Plieva
Ana
A
Santos
Rajni
R
Hatti-Kaul
D000327:Adsorption; D001407:Bacillus / Q000254:growth & development* / Q000378:metabolism*; D019149:Bioreactors / Q000382:microbiology*; D018929:Cell Culture Techniques / Q000379:methods*; D018914:Cells, Immobilized / Q000502:physiology; D020099:Coated Materials, Biocompatible; D003080:Cold Temperature; D003505:Cyclodextrins / Q000096:biosynthesis*; D004789:Enzyme Activation; D005782:Gels; D005964:Glucosyltransferases / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D008567:Membranes, Artificial; D011137:Polystyrenes; D011142:Polyvinyl Alcohol; D011145:Polyvinyls; D013696:Temperature
D020099:Coated Materials, Biocompatible; D003505:Cyclodextrins; D005782:Gels; D008567:Membranes, Artificial; D011137:Polystyrenes; D011145:Polyvinyls; C012101:XAD-4 resin; D011142:Polyvinyl Alcohol; D005964:Glucosyltransferases; C019963:cyclomaltodextrin glucanotransferase