Effect of micro-nanobubbles with different gas sources on the growth and metabolism of chemoautotrophic microorganisms

Recent Advancements and Strategies of Improving CO2 Utilization Efficiency in Bio-Succinic Acid Production

“…Ye et al [74] proposed to boost oxygen diffusion via MNBs; the oxygen transfer coefficient and rate of MNBs were 0.160 min −1 and 0.382 kg•m −3 •h −1 (about four times and five times greater than those of conventional aeration, respectively). For example, in the work of Guo et al, CO 2 -MNBs had a promoting effect on the growth of Sinomicrobium oceani WH-15 at MNB concentrations of 5-10% in water, whereas the inhibitory effect appeared from 20% [75] because a high concentration of MNBs produced a large number of hydroxyl radicals and other reactive oxygen components, which was unfavorable to the microorganisms [76]. Additionally, CO 2 -MNBs may also facilitate CO 2 fixation by autotrophic microorganisms because more carbon sources are provided [75].…”

“…For example, in the work of Guo et al, CO2-MNBs had a promoting effect on the growth of Sinomicrobium oceani WH-15 at MNB concentrations of 5-10% in water, whereas the inhibitory effect appeared from 20%[75] because a high concentration of MNBs produced a large number of hydroxyl radicals and other reactive oxygen components, which was unfavorable to the microorganisms[76]. Additionally, CO2-MNBs may also facilitate CO2 fixation by autotrophic microorganisms because more carbon sources are provided[75].Haapala et al observed that in papermaking-process waters, the presence of dry refined pine kraft pulp fibers (average fiber length: 1.52 mm) remarkably decreased the size of bubbles measured during a 30 s period after de-pressurizing the air-saturated suspension from 300 kPa to normal atmospheric pressure. Moreover, adhesion of the kraft wood fiber material to the air bubbles further decreased the bubble rise velocities.…”

Use of Nanobubbles to Improve Mass Transfer in Bioprocesses

“…The application of micronanobubbles for the bioconversion of CO 2 to CH 4 enhances the mass transfer of H 2 and biomass growth and significantly improves bioconversion efficiency [69]. Guo et al [70] reported that micro-nanobubbles could improve mass-transfer efficiency in liquids and reduce the redox potential, which is relevant for the growth and metabolism of chemoautotrophic microorganisms. W. Xiao et al [71] found that nanobubble aeration effectively provided extra oxygen for microbial aggregates, achieving a notable improvement in the structural characteristics and performance of microbial aggregates.…”