Release of polysaccharide by sonication of cells (<Emphasis Type="Italic">Porphyridium sp.</Emphasis>)

The paper deals with experimental data concerning the interaction of acoustical waves with microbial cell (Porphyridium sp.). The aim of the present paper was to increase the amount of biopolymer released from the microorganisms biomass with the aid ultrasound irradiation without scission or a decrease in the molecular weight. The results indicated that the amount of polysaccharide (for example) released from the cell pellet could be enhanced by ultrasound, depending on the frequency and energy of the ultrasound. The sugar composition remain the same, but the apparent viscosity of polysaccharide aqueous solutions decreased, indicated that some changes in the molecular shape and size occurred. When ultrasound irradiation was applied in the presence of either CO₂ or CO₂ + H₂, the apparent viscosity of polysaccharide aqueous solutions increased (versus usual ultrasound treatment). The text was submitted by the authors in English.