Isolation and characterisation of polysaccharides from traditionally known Chinese medicinal mushrooms

Abstract

Medicinal mushrooms are known for their traditional use for the treatment of various diseases including diabetes, cancer and cardiovascular diseases. Mushrooms have been traditionally used for curing numerous life-threatening diseases such as cancer, Tuberculosis, Parkinson's and Alzheimer. Cancer is one of the leading causes of death worldwide and finding better therapeutics to treat this disease is an urgent need. Literature demonstrates the potential of mushroom polysaccharides for their therapeutic value with significant immunostimulatory and anticancer activities with least side effects. A few polysaccharides from medicinal mushrooms (e.g. Polysaccharide Krestin, Polysaccharopeptide) are already in clinical use to treat cancer. This research therefore aims to isolate polysaccharides with immunomodulatory, prebiotic and anticancer properties from traditionally known medicinal mushrooms Ganoderma lucidum, Cordyceps sinensis and Trametes versicolor. The objectives of this research are to study the biological activities relevant to anticancer therapy and to evaluate the structure- function relationship of mushroom polysaccharides. It is therefore expected that these mushrooms have tremendous potential for the discovery of polysaccharides with immune enhancing, prebiotic and anti-cancer properties and hence chosen for this study. A total of six polysaccharides have been identified in this thesis from two medicinal mushrooms (G. lucidum and C. sinensis). Four of these fractions (GLP-1, GLP-2, GLP-3, CSP-1) have displayed significant radical scavenging activities. These activities correlated well with molecular masses and structural elements. GLP-1 and GLP-3 displayed highly significant immunostimulatory activities with respect to both cytokines and are extremely important candidate for immunotherapeutic applications. CSPs and GLPs have also displayed significant prebiotic activities that are highly significant. Overall, the results presented in this thesis strongly suggest immune enhancing, prebiotic and direct anticancer activities of polysaccharides from G. lucidum and C. sinensis (GLPs and CSPs). It is therefore concluded that these polysaccharides form potential candidates for combination "immuno-chemotherapy". It is therefore suggested that, pre-treatment of cancer patients with immunostimulatory and prebiotic mushroom polysaccharides identified in this research to activate cancer microenvironment and to improve gut microbiota, followed by therapy with suitable immune checkpoint inhibitors is expected to produce enhanced outcomes for cancer patients. It is in this context that the immune enhancing and prebiotic mushroom polysaccharides discovered in this research have great potential in the treatment of cancer.

Date of Award	2020
Original language	English