This study was to investigate the effects of polysaccharide chain conformation on ultrasonic degradation of curdlan, a high MW β-glucan with wide applications. The ultrasonic degradation was performed in alkaline solution at 0.1 M and 0.
View Article and Find Full Text PDFHigh-intensity ultrasound (US) was applied to facilitate the extraction of intracellular and extracellular polysaccharide-protein complexes (PSPs) from the viscous mycelial fermentation broth of a medicinal fungus Cordyceps sinensis Cs-HK1. The US treatment caused the disruption of fungal mycelia, a dramatic reduction of the apparent broth viscosity, and the release of intracellular products into the liquid medium. The degree of mycelium disruption and the rate of intracellular product release were dependent on US power intensity, treatment period and biomass concentration of broth.
View Article and Find Full Text PDFA high molecular weight (MW) exopolysaccaride (EPS) fraction EPS1 was isolated from the fermentation broth of a medicinal fungus Cordyceps sinensis Cs-HK1 and partially degraded by high-intensity ultrasound (US) into a lower MW fraction EPS1U. EPS1U exhibited a single, symmetric peak on size exclusion chromatography with an average MW of 730kDa by light scattering analysis. It had a much lower intrinsic viscosity (1.
View Article and Find Full Text PDFHigh-power ultrasound (20 kHz) was applied to modify the physicochemical properties of a high-molecular weight (MW) exopolysaccharide (EPS) from mycelial culture of a medicinal fungus. At 35 W/cm(2) or higher ultrasound power, the apparent and intrinsic viscosities of EPS solution dropped by nearly 85% within 10 min, and the water solubility was increased by more than fourfold. The ultrasonic treatment led to a notable reduction of the maximum MW and a more uniform MW distribution, but no significant change in the primary structure of the EPS molecules.
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