Optimised isolation of polysaccharides from <i>Lentinula edodes</i> strain NCBI JX915793 using response surface methodology and their antibacterial activities

<div><p>Mycelial growth in a defined medium by submerged fermentation is a rapid and alternative method for obtaining fungal biomass of consistent quality. Biomass, exopolysaccharides (EPS) and intracellular polysaccharides (IPS) production were optimised by response surface methodology in <i>Lentinula edodes</i> strain LeS (NCBI JX915793). The optimised conditions were pH 5.0, temperature 26°C, incubation period of 25 days and agitation rate of 52 r/min for <i>L. edodes</i> strain LeS. Under the calculated optimal culture conditions, biomass production (5.88 mg mL^{− 1}), EPS production (0.40 mg mL^{− 1}) and IPS production (12.45 mg g^{− 1}) were in agreement with the predicted values for biomass (5.93 mg mL^{− 1}), EPS (0.55 mg mL^{− 1}) and IPS production (12.64 mg g^{− 1}). Crude lentinan exhibited highest antibacterial effects followed by alcoholic, crude and aqueous extracts. The results obtained may be useful for highly effective yield of biomass and bioactive metabolites.</p>