METHOD OF ISOLATING BIOLOGICALLY ACTIVE FRACTION CONTAINING CLINICALLY ACCEPTABLE NATIVE S-LIPOPOLYSACCHARIDES OBTAINED FROM BACTERIA PRODUCING ENDOTOXIC LIPOPOLYSACCHARIDES

摘要

A biologically active fraction comprising S-lipopolysaccharide (LPS) from Gram-negative bacteria, which produces endotoxin LPS as a main component, is disclosed. This fraction is selected from the group consisting of D-glucosamine and β-hydroxydecanoic acid, β-hydroxydodecanoic acid, β-hydroxytetradecanoic acid and β-hydroxyhexadecanoic acid in lipid A of S-LPS. The molar ratio of β-hydroxy acid is about 2: 1-4, and the molar ratio of D-glucosamine and higher fatty acids linked by amide and ester bonds in lipid A of S-LPS is about 2: 3-7. Also disclosed is a method of isolating BAF comprising predominantly Gram-negative S-LPS producing endotoxin S-LPS.;The obtained BAF has the pyrogenicity, low toxicity, and high immunogenicity of commercial polysaccharide vaccine levels, and can be used as a vaccine for mammals including humans. They may be considered as inducers of cytokines and as prophylactic resistant antishock agents.