Cyclodextrin production by cyclodextrin glycosyltransferase from Bacillus circulans DF 9R.
Cyclodextrins (CD) are cyclic oligosaccharides with multiple applications in the food, pharmaceutical, cosmetic, agricultural and chemical industries. In this work, the conditions used to produce CD with cyclodextrin glycosyltransferase from Bacillus circulans DF 9R were optimized using experimental designs. The developed method allowed the partial purification and concentration of the enzyme from the cultural broth and, subsequently, the CD production, using the same cassava starch as enzyme adsorbent and as substrate. Heat-treatment of raw starch at 70 degrees C for 15 min in the presence of adsorbed cyclodextrin glycosyltransferase allowed the starch liquefaction without enzyme inactivation. The optimum conditions for CD production were: 5% (w/v) cassava starch, 15 U of enzyme per gram of substrate, reaction temperature of 56 degrees C and pH 6.4. After 4h, the proportion of starch converted to CD reached 66% (w/w) and the weight ratio of alpha-CD:beta-CD:gamma-CD was 1.00:0.70:0.16.
Szerman
Natalia
N
Universidad Nacional de Luján, Departamento de Ciencias Básicas, Luján 6700, Buenos Aires, Argentina.
Schroh
Ignacio
I
Rossi
Ana Lía
AL
Rosso
Adriana Mabel
AM
Krymkiewicz
Norberto
N
Ferrarotti
Susana Alicia
SA
D001407:Bacillus / Q000201:enzymology*; D003505:Cyclodextrins / Q000096:biosynthesis*; D005964:Glucosyltransferases / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D013379:Substrate Specificity; D013696:Temperature
D003505:Cyclodextrins; D005964:Glucosyltransferases; C019963:cyclomaltodextrin glucanotransferase