Novel highly branched water-soluble heteropolysaccharides as immunopotentiators to inhibit S-180 tumor cell growth in BALB/c mice

The in vitro antitumor activities and in vivo immunomodulatory effects of water-soluble highly branched heteropolysaccharides isolated from Rhizoma panacis Japonici were evaluated by three cell lines and BALB/c mice implanted with Sarcoma 180 (S-180) tumors. The heteropolysaccharides showed potent tumor therapeutic effect by potentiating the animal's immune responses including an increase in white blood cell count and lymphocyte number. The heteropolysaccharides also induced apoptosis in the S-180 cells and alleviate the short-term side effect of cisplatin (DDP) to the animal during the treatment period. The bioactivity of the heteropolysaccharides might be due to their unique structures that had an α-(1 → 4)-d-glucan main chain with side chains containing mannose and galactose residues, a spherical chain conformation, as well as high water solubility, all of which facilitated their interaction with the surface receptors of the immune cells.     

Exocellular polysaccharides produced by lactic acid bacteria

Abstract The production of homopolysaccharides (dextrans, mutans) and heteropolysaccharides by lactic acid bacteria, their chemical composition, their structure and their synthesis are outlined. Mutans streptococci, which include Streptococcus mutans and S. sobrinus produce soluble and insoluble α-glucans. The latter may contain as much as 90%α-1–3 linkages and possess a marked ability to promote adherence to the smooth tooth surface causing dental plaque. Dextrans produced by Leuconostoc mesenteroides are high molecular weight α-glucans having 1–6, 1–4 and 1–3 linkages, varying from slightly to highly branched; 1–6 linkages are predominant. Emphasis is put on exopolysaccharide producing thermophilic and mesophilic lactic acid bacteria, which are important in the dairy industry. The produced polymers play a key role in the rheological behaviour and the texture of fermented milks. One of the main problems in this field is the transitory nature of the thickening trait. This instability is not yet completely understood. Controversial results exist on the sugar composition of the slime produced, but galactose and glucose have always been identified with galactose predominating in most cases.