Experiments on the production of dextrans and riboflavinylglycosides from sucrose and riboflavin were carried out with various strains of Leuc. mesenteroides. It was observed that the yield of riboflavinylglycosides did not run paralled to the yield of dextrans not only in growing cultures but also in enzymic reactions, and moreover higher yields of riboflavinylglycosides were observed with such strains as to produce dextrans containing higher ratios of branching chains.
