Full Spectrum Beta-Glycans-Polysaccharides (FS-BGP)
Many wood decomposing mushrooms have been shown to possess both water soluble
and insoluble beta-glycans (or beta-glucans; Dong and Fang, 2006;
Wang et al., 2001a; Bukhman). These long chains of polymeric glyconutrients are composed
of repeating units of simple sugar molecules, such as glucose. The number of sugars joined
together can be extremely large, hence the term “polysaccharides”.
Beta-glycans derived from medicinal fungi differ as they contain hundreds of sugar molecules joined by both linear and branching linkages. These fungal derived polysaccharide structures are important and necessary for maintaining robust health and longevity. They are becoming increasingly recognized and explored with regards to their varied effects. So prominent and varied are their effects that the study of beta-glycans polysaccharides has recently been termed glycomics (Sierpina and Murray, 2006) and their actions on the immune system have been described as biological response modifiers (Foon, KA. 1989). This paradigm purports that specific glyconutrients impact diverse physiological and immune modulatory/regulatory function.
Studies performed in Japan during the 1960’s identified that specific mushrooms contain hot water soluble components that, when administered to mice, acted to prevent tumour growth and in many cases caused complete tumour regression (Ikekawa et al., 1968; Shibata et al., 1968). This observation was further explored in a multitude of medicinal mushrooms, most notably Shiitake and Reishi, which coincidently had been used for millennia as folk remedies for precisely the conditions of cancer (Wasser 2002; see below), debilitation, life extension etc, which the researchers investigated. Generally these desirable factors were shown to be polysaccharides of the beta-glycan type where they were soluble in hot water and could be extracted from both the mycelium and the fruiting body.
One of the most common components of the extracted polysaccharides was shown to be simply glucose molecules joined to one another in specific ways. Collectively they were termed beta-glycans but variations on this theme can correlate with different physiological effects and hence be exploited as such for immune modulation. It has been demonstrated that when these beta-glycans are consumed, they exert a modulatory effect on the immune system. This immunomodulation in response to fungal polysaccharides is not surprising since many pathogenic and harmful fungi are present in the environment. Such fungal infections are devastating and the immune system has evolved to specifically recognize and react aggressively to invading molds. Since the polysaccharides derived from key “benign” culinary mushrooms resemble those present in the multitude of opportunistic fungal pathogens, the immune system acts to mount an enhanced surveillance response to even these benign food derived materials – hence the term functional foods (Cheung, 2008)! The net effect is an alert immune system that by default also reacts to developing cancers (antitumor; Wasser 2002), rogue – potentially pre-cancer cells and metastatic cancer cells. The term immunomodulation more adequately describes this effect because autoimmune conditions are also ameliorated by mushroom derived functional foods (Cheung, 2008).
In addition to the fruiting body itself and the mycelium, the culture broth also appears to possess desirable anti-tumor and immune enhancing compounds (Wang et al., 2001a; Bukhman et al., 2007). This is not surprising as the mycelium grows in its natural environment, it secretes enzymes and cellular metabolites as a way of harnessing nutrients and warding off competing fungi. This natural adaption can be utilized to harness additional biological response modifiers. In a study by Wang and collaborators, it was determined that the culture broth possessed extracellular polysaccharides. These polysaccharides conferred anti-pulmonary metastatic and immunoenhancing properties and the immune enhancing effects were shown to be conferred by increasing the levels of both T cells and macrophages, key and principle members of the mammalian immune system (Wang et al., 2001a).
Thus to derive the most benefits, one should select a product that combines mycelium from several of the key medicinal mushroom to ensure the broadest spectrum of beta-glycan polysaccharides are presented unless a particular condition is being targeted (as listed in Table 1). In addition, a complete product which utilize both the mycelium and valuable extracellular components should also be selected.