THE OPTIMIZATION OF THE ENZYMATIC-SYNTHES IS OF BETA-1,3-1,6-GLUCOOLIGOSACCHARIDES AND THEIR BIOLOGICAL-ACTIVITY

A study of the enzymic synthesis of beta-1,3; 1,6-glucooligosaccharide s by means of transfer of beta-1,3-linked glucose residues from a dono r, laminarine, to an acceptor, gentiotetraose, carried out by endo-bet a-1,3-glucanase from sea molluscs was continued. Measuring optical rot ation of the reaction mixture was selected as a convenient method for monitoring the reaction. The biological activity (simulation of soybea n immunity) was found in the fractions with [alpha]D value below -40-d egrees. It was shown that to increase the yield of these active substa nces, the reaction should be stopped at the [alpha]D value about -10-d egrees. NMR spectroscopy and methylation analysis were used to corrobo rate the chemical structure of the biologically active substances. Bot h methods have shown an increase of the amount of 1 --> 3,6-glucose re sidues with regard to gentiooligomers.