Bacteriostatic action of oligosaccharides prepared from alginate by enzymatic degradation

Oligosaccharides were prepared from alginate, guluronate-rich blocks, and mannuronate-rich blocks of alginate by bacterial alginate lyases, and were examined for antimicrobial action against four strains of aerobic and two strains of anaerobic bacteria, as well as six strains of fungi. O1-igosaccharides from guluronate-rich and mannuronate-rich blocks showed significant activity against the aerobic and anaerobic bacteria, but none of the oligosaccharides were antifungal. The bacteriostatic action of the oligosaccharides differed depending on the degree of polymerization and hepta- and hexa-saccharides were highly bacteriostatic. None of the saccharides tested were utilized by any of the seven strains of intestinal bacteria.