3.1. Beta-1,3/1,6-glucans in Oriental medicine
Extracts of the Shiitake mushroom (Lentinus edodes) in Japan and of the mushroom known as “Lingzhi” (Ganoderma lucidum) in China have a recognized position in traditional medicine of the Orient. The oldest Chinese medical dictionary (“Shen Lungs Medica”) and the “bible” of Chinese herbal medicine (“The Chinese Herbal Materia Medica”) rate Lingzhi extracts as a “spiritual essence” which strengthens the body and cures cancer, urinary disorders, fever diseases and arthritis/rheumatism. The wisdom of ancient medicine, generated by experience, has gained strong support from Western scientific research which has indeed confirmed that beta-glucans extracted from these mushrooms inhibit tumor growth and increase resistance to infections by virus, bacteria and parasites.
3.2. Zymosan and beta-1,3/1,6-glucan in baker’s yeast
More than 50 years ago it was discovered by scientists in the United States (Pillimer and Ecker) that disrupted and enzyme digested baker’s yeast contained a material which interacted with serum components that are involved in the destruction of infectious microorganisms. In 1957, Benaceraff and Sebastian presented a paper on the stimulating effect of a crude cell wall preparation from baker’s yeast (called zymosan) on macrophages. In the 1960s, DiLuzio and his coworkers in New Orleans showed that the active component in zymosan was beta-1,3/1,6-glucan and that this component had the ability to enhance disease resistance and limit growth of tumors in humans.
During the last 20-30 years, much work has been devoted to develop methods to extract this beta-1,3/1,6-glucan from baker’s yeast in pure and active form, and to reveal its chemical structure and mode of action on the immune system. Today the mode of action of the yeast beta-1,3/1,6-glucan is known in great detail. Its ability to prevent infections caused by virus, bacteria, fungi and parasites has been documented in hundreds of scientific papers, and confirmed by practical experience.
The few toxicological events observed after administration of yeast beta- 1,3/1,6-glucan are restricted to intravenous or intraperitoneal injection (Di Luzio et al. 1980; Takahashi et al. 2001; Williams et al. 1996).