Abstract: | Systematic isolation and purification of the biologically active component of ginseng extract were followed by observing the incorporation of labeled leucine into serum protein at 6 hr after a single intraperitoneal injection in a mouse. Ginseng saponin mixture (fraction 5) exhibited high activity for such incorporation. Seven saponins were isolated from fraction 5 by means of preparative TLC, and assayed. Administration of all these saponins (ginsenoside-Rb2, Rc, Rc2, Rd, Re, and Rg1)except for ginsenoside-Rb1, caused an increase of leucine incorporation over that in control animals. The incorporation rate was directly proportional to the dose in the case of ginsenoside-Rd, which had the highest activity. The increase specific radio-activity of serum protein was not due to a decrease in the pool size of free amino acids in the liver. It was conclusively shown that the active component stimulating serum protein biosynthesis is saponin. |