Effects of ultrasound on Microcystis aeruginosa cell destruction and release of intracellular organic matter

Improving soaking efficiency of soybeans through sweeping frequency ultrasound assisted by parameters optimization

“…It is observed that SPC in SFU group is the highest significantly, but that permeated into the soaking solution increases slightly. It indicates that the hydroxyl radical produced by cavitation can oxidize the cell membrane lipid and change the membrane permeability [58] . When the cell membrane loses semi-permeability, ions will leak from cells.…”

Ultrasound for microalgal cell disruption and product extraction: A review

“…The chemical effect of ultrasonic cavitation generally refers to the oxidation by free radicals, including hydroxyl radicals ( . ), hydrogen radicals ( ), perhydroxyl radicals ( ) and others [ [29] , [32] ]. Reactive hydroxyl and hydrogen radicals ( .…”

“… and ) are generated from the decomposition of water vapor trapped in the collapsing bubbles due to the extremely high temperature and pressure formed in collapsing bubbles [ [25] , [26] ], and their recombination or reaction with other gaseous species in the bubble leads to the formation of active species such as , and [ [18] , [32] ]. It has been reported that more hydroxyl radicals were generated at high frequencies than at low frequencies (1120 kHz > 740 kHz > 20 kHz) [ 29 ]. Besides, the amount of free radicals increases with the sonication time [ [25] , [29] , [33] ].…”

“…It has been reported that more hydroxyl radicals were generated at high frequencies than at low frequencies (1120 kHz > 740 kHz > 20 kHz) [ 29 ]. Besides, the amount of free radicals increases with the sonication time [ [25] , [29] , [33] ]. Upon the generation of free radicals, cell membrane lipids can be oxidized and membrane permeability can be changed, leading to the release of intracellular substances [ 29 ].…”

“…The resonance radius of 3.3 μm is very close to that of Chlamydomonas concordia of 3–6 μm and could effectively excite mechanical resonance and induce cell disruption. Formation of hydroxyl radicals were also found to be correlated with ultrasonic frequency [ 29 ]. Compared with lower frequency, more gas nuclei could reach the resonance size more quickly and generates greater collapse pressure at higher frequency [ 40 ].…”