Subcritical Water Extraction of Polysaccharides Using a Semi-Batch Extractor

Subcritical water is an environmentally friendly method with a wide range of applications, such as extraction,hydrolysis, and wet oxidation of organic compounds. Here, water at subcritical conditions was applied to extractpolysaccharides from Ganoderma lucidum (G. lucidum) and barley grains at 120 – 180 oC and 4.0 MPa using asemi-batch system. The liquid products were directly micronized and contacted with hot air to form microsphereparticles. During extraction process, cell wall disruptions of G. lucidum and barley grains took place, allowingthe removal of the polysaccharides isolating other constituents in G. lucidum and barley grains viaautohydrolysis. Scanning electron microscope (SEM) images described that the particle products produced hadsphere and wrinkled morphology of particles with diameters varying from 1 to 10 μm. The experimental resultrevealed that the particles formed from G. lucidum and barley grains extract contained 40-45% and 30-35%weight β-glucan, respectively.