Recovery of water-soluble compounds from Ganoderma lucidum by hydrothermal treatment

The polypore fungus Ganoderma lucidum provides bioactive compounds containing several triterpenoids and polysaccharides that are reported to posses anti-cancerous and immunomodulatory properties. In this study, we determined the optimal conditions for extracting water-soluble polysaccharide compounds present in the ground form (3-mm particle size) of G. lucidum using water in subcritical conditions at distinct temperatures by two methods: batch-type subcritical water extraction and semi-continuous-type extraction. The optimal condition where solubility is higher to recover the maximum total amount of β-glucan from G. lucidum (0.44 mg/100 g dried sample) was determined to be 473 K at 10 MPa, with a water flow rate of 1 ml/min for 130 min. For batch-type and semi-continuous-type extractions, the best solubility was obtained at 473 K having efficiencies of 78.1% and 57.4%, and the highest extracted amounts of total WSOC were 328 and 241 mg WSOC/g dry sample, respectively.