Evaluation of the biological activities of β-glucan isolated from Lentinula edodes.

Lentinula edodes (shiitake) is an edible mushroom that contains many constituents and β-glucan is considered a major polysaccharide. This study, therefore, aimed to characterize β-glucan and evaluate its activities. Fresh fruit bodies of L. edodes were used for β-glucan extraction and followed by analyses via Fourier transform infrared, nuclear magnetic resonance and high performance liquid chromatography confirming its characteristic structure. For evaluating biological activities of β-glucan, different concentrations (0·1-3·5 mg ml -1 ) were assessed. The optimal dose was 3·5 mg ml -1 that showed the highest scavenging radical ability (75·3%) confirms antioxidant activity, strong inhibition of the peroxyl radical (80·9%) to inhibit lipid peroxidation, elevation the inhibition percentage of both α-amylase (73·4%) and α-glucosidase (70·3%) indicates the antidiabetic properties, and highest AFB1 reduction (88%) which ensured the aflatoxin-detoxifying ability. In addition, antifungal activity of β-glucan was evaluated to inhibit sporulation process in Aspergillus niger and recorded with minimum inhibitory concentration of 2·5 mg ml -1 and minimum fungicidal concentration of 3 mg ml -1 . In a dose-dependent manner, higher concentration of β-glucan affects viability of tumour cells concomitant induces potent anti-cancer immune responses and inhibited the activity of topoisomerase I which are considered an important target for cancer chemotherapy. Therefore, L. edodes-β-glucan has the potential to act as a suggestive agent for antioxidant, antidiabetic, antifungal activity and aflatoxin detoxification.