The use of mushroom hydrolysate from waste bag-log as thenitrogen source to mycelium biomass and exopolysaccharide production inPleurotus eryngii cultivation

Abstract

In this study, Pleurotus eryngii head part waste in a bag-log was collected and processed to yieldmushroom hydrolysate powder (MHP). To test its stimulatory effect, a P. eryngii submerged culture wasconducted. The prepared MHP (1.6%) and glucose (2%) were found to be the best sources for bothmycelial biomass and EPS productions. A specific growth rate of 0.68 day 1, and a specific EPS yield of9.55 g/g-dry-cell-weight were obtained under these conditions. It was also found that MHP gave highermycelial biomass growth rate (2.05 g/L/day), and EPS yield (92 mg/L) than those of yeast extract. In 5-Lfermentation with MHP as nitrogen source, high mycelial biomass growth rate (2.44 g/L/day) and EPSyield (312 mg/L) were obtained. In the solid state culture, P. eryngii hyphae growth rate in MHP agar(6.43 0.21 mm/day) was better than that in PDA (4.57 0.23 mm/day). By using PCA and cluster analysis,the major amino acids of MHP displayed a close similarity to those of P. eryngii mycelial hydrolysate powder(PEMHP)