Synthesis of fructooligosaccharides using extracellular enzymes from rhodotorula Sp

Abstract

Considering the great biodiversity of the still unexploited Brazilian environment, efforts were made to select microorganisms capable of producing fructooligosaccharide (FOS). Amongst 495 interesting isolated yeast strains, one in particular, identified as a Rhodotorula red yeast strain isolated from flowers from the Brazilian tropical biomass, was able to produce an effective thermostable extracellular enzyme, with both sucrose hydrolytic and transfructosylating activities. The best operational conditions for this enzyme were determined to be in a pH range from 3.8 to 4.3 and at temperatures of around 65C. Under these conditions, the transfructosylating activity reached its maximum, being more than 10 times higher than the hydrolytic activity. The synthesis of fructooligosaccharides from sucrose resulted in total conversion of the substrate into FOS (48%), glucose (31.3%) and fructose (20.7%). In addition, it was shown that the synthesized FOS had a prebiotic effect, promoting the growth of probiotic bacteria. © 2010, The Author(s). Journal compilation © 2010, Wiley Periodicals, Inc.