Monday, May 2, 2011
Grand Ballroom C-D, 2nd fl (Sheraton Seattle)
Consumers have intensified their search for foods with functional properties, improving their life quality and avoiding the development of specific illnesses. The fungus Agaricus blazei (Agaricus brasiliensis), known as the sun mushroom, is a Basidiomycete whose oligosaccharides derived from the beta-glucans present functional properties. Production of beta-glucanases able to promote the degradation of beta-(1→3)(1→6)-glucans is essential in the development of oligosaccharides that exhibit biological activity. Different methods of hydrolysis have been used to obtain oligosaccharides that present prebiotic and immunomodulator activities. Development of an enzymatic hydrolysis technology viable for obtaining glucooligosaccharides should be pointed out, which will make possible to study their action as prebiotics. Then, this work showed that the beta-1,3-glucanase of Trichoderma harzianum Rifai, produced in conditions optimized by response surface methodology using an extract of A. blazei as substrate, hydrolyzed beta-glucans of A. blazei and produced glucooligosaccharides of biological interest. The crude enzyme obtained from Trichoderma harzianum Rifai resulted in 14 % of glucan hydrolysis and 41.5 % of laminarin hydrolysis, after 60 min. Gentiobiose and laminaritriose were detected in the enzymatic hydrolysates of beta-glucan and laminarin, by analysis of high pressure liquid chromatography in ion chromatograph (HPAEC/PAD). Also, laminaritetraose, celotetraose and celotriose were identified and quantified in the hydrolysate of beta-glucan of A. blazei. The differences in the results of laminarin and glucan hydrolysis may be, probably, explained by the differences in the degree of polymerization, conformation and branching of each polysaccharide.
Keywords: Trichoderma harzianum Rifai, Agaricus blazei, enzymatic hydrolysis; glucooligosaccharides.
Acknowledgements: FAPESP e CNPq