Medicinal Mushroom Products:Nutriceuticals and/or Pharmaceuticals?

Although the effectiveness of mushroom products(mushroom derivatives) has been confirmed repeatedly by numerous laboratory experiments and,in some cases,human trials,precisely how these products work is still a matter of conjecture.Studies on the effectiveness of mushroom products fall into two general categories.One approach has been to isolate and determine the bioactivity of individual mushroom components within a particular class of compounds(e.g.polysaccharides,lectins,triterpenoids,fungal immunomodulatory proteins).The active principal component is then sold in refined or purified form,e.g.the polysaccharide lentinan from the edible/medicinal mushroom Lentinula edodes.Such an approach is certainly valid if the objective is to focus on a single mushroom-derived substance for the treatment of specific disease conditions,e.g.cancers or strokes.In such cases,the products might be(and have been) developed and marketed as prescription drugs.However,an alternative approach is not to focus on a single component within a class of compounds but on groups of compounds that improve overall health and the general quality of life.These composite formulae,in which several different compounds together contribute to the beneficial effect of the mushroom,could then be used collectively as a dietary supplement(nutriceutical).Thus,the medicinal effects afforded by medicinal mushroom products may be attributable to several quite different types of compounds present in the mushrooms,e.g.polysaccharides,lectins,triterpenoids and fungal immunomodulatory proteins.These compounds,and possibly others yet to be identified,appear to act in concert in contributing to the documented anticancer,antitumour,antiviral,antibacterial and immunomodulating properties of the mushroom.Therefore,mushroom nutriceuticals may be deemed to have multifunctional values,the essence of which depends on the integrated effects of the various compounds.Certainly,the overwhelming majority of mushroom-based products currently available are not single components but combinations of several groups of compounds("crude extracts") that together contribute to the overall medicinal effect of the product.Therefore,it is important that future development of mushroom nutriceuticals places emphasis on investigating the functionality and interaction of the groups of compounds found in mushrooms.In some cases,it may be more desirable to consider the total medicinal effect(s) of mushroom "crude extracts"(comprising groups of compounds) and then to ascertain the contributions made to the overall activity by individual components.The consistency of the "crude extracts",both in terms of the overall chemical composition and in the actual levels of active components,between different batches could be standardized on the basis of one or two of the main components.This is essential for ensuring some degree of uniformity in prescribed dosages.Thus,while the minimum dosage of an active component required to bring about the desired therapeutic effect is often known for similar products,e.g.hypericin in extracts of St.John's Wort,this is generally not the case where mushroom "crude extracts" are concerned.This is an area where scientific validation can increase knowledge of the products themselves as well as contributing to product quality control.