Substance TH69E and immunopotentiator containing the same

A substance TH69E having the characteristics:

• (a) elemental analysis:
• C:24.25%, H:
• 4.46% and N:6.55%
• (b) molecular weight:
• about 60,000 .+-.15,000 (Biogel P-Series Column);
• (c) color:
• white amorphous powder;
• (d) decomposition point:
• 80.degree. C. (as determined by a capillary method with use of Silicone Oil WF-30--the color changes to brown);
• (e) ultraviolet absorption spectrum:
• as shown in FIG. 1 of the drawings;
• (f) infrared absorption spectrum:
• as shown in FIG. 2 of the drawings;
• (g) pH:
• 6.7 to 7.1 in an aqueous solution;
• (h) solubility:
• soluble in water, and insoluble in ethanol, acetone, n-hexane, n-butanol and phenol;
• and
• (i) color reactions:
• phenol-sulfuric acid reaction, anthrone reaction, Molisch reaction, orcinol-hydrochloric acid reaction, Ninhydrin reaction being positive, and Elson-Morgan's reaction being negative,
• prepared by a process, comprising:
• (a) culturing a strain of Streptococcus faecalis having the identifying depository number of ATCC-31663 in a nutrient medium until a sufficient amount of the substance is obtained;
• (b) extracting said bacterial strain obtained from the nutrient medium with hot water;
• (c) treating the aqueous solution at least once with water saturated with a phenolic compound;
• and
• (d) precipitating said TH69E from said treated aqueous solution.