The researchers controlled for intervening variables such as a possible Griess reaction or bacterial contamination that might induce iNOS. Furthermore, the researchers were able to isolate specific components in the ginseng aqueous solution that were responsible for the NO production: polysaccarides. The authors also note that macrophages are instrumental in the immune response: they produce NO; NO in turn acts as an antimicrobial and antiviral compound. A sustained NO production may be a key to preventing serious disease. Ginseng is used in Traditional Chinese Medicine as a tonic herb, one that has an overall effect on preventing illness, enhancing immune response, and defending the body against pathogens. Prior research, listed in the Results section of the Friedl, et al. (2001) report, has substantiated the claims of traditional medicine. Research using aqueous solutions of Panax ginseng has also yielded results suggesting that the root enhances antibody formation. Oral administration of Panax ginseng in vivo studies also show promising results of the herb on stimulating the body's natural defenses especially against common respiratory infections.

The current research deepens the body of literature already extant on Panax ginseng. By isolating the polysaccarides as the compounds that are mainly essential for nitric oxide stimulation in cells, the researchers potentially contribute to the growing compendium...

The current research also isolates the main reason why Panax ginseng is effective in enhancing immunity: ginsenosides stimulate the production of NO and NO is associated with enhanced natural defenses against pathogens. The results also depended on dose: the greater the exposure of the murine macrophages to the ginsenosides, the greater the production of NO.
However, the authors do suggest that current methods of standardizing powdered, commercially available ginseng may not be as effective as intended. The powdered Panax ginseng such the Nature's Way brand available in stores and used in the current study, contained standardized amounts of ginsenosides. The current research shows that not all ginsenosides are responsible for the immune system response. Polysaccharides are the compounds most responsible for enhancing the body's natural immune defense via iNOS, the simulation of nitric oxide. Because it is the iNOS action that prevents infection, standardized extracts of Panax ginseng should probably be reformulated to contain the maximum amount of polysaccharides: if the herb is being marketed specifically as an immune system enhancer. The wide range of tonic effects claimed by Traditional Chinese Medicine might mean, however, that the whole gamut of ginsenosides may be useful in helping the body heal.