Abstract
Methods for efficient extraction and simple purification of the lipopolysaccharide specific for Mycobacterium tuberculosis were developed. Crude lipopolysaccharide was obtained from sterilized cells through mechanical disintegration, Triton X-100 extraction, ethanol precipitation, glucosidase digestion, and gel-filtration chromatography. The lipopolysaccharide was further purified by treatments with pyridine-methanol and chloroform-methanol to remove the contaminating glycolipids and phospholipids, and by digestion with the immobilized trypsin to remove the contaminating proteins. The purified lipopolysaccharide was composed of a polysaccharide consisting of D-mannose and D-arabinose, and fatty acids, mainly palmitic, tuberculostearic, and stearic acids, which were bound in ester linkages. The lipopolysaccharide had strong tumor regressing activity on the mouse fibrosarcoma.
