An alternative method to improve the settleability of gas-vacuolated cyanobacteria by collapsing gas vesicles

作者：Abeynayaka Helayaye Damitha Lakmali; Asaeda Takashi^*; Tanaka Kyoko; Atsuzawa Kimie; Kaneko Yasuko; Nishda Hidenori; Inada Seiichi

来源：Water Science and Technology: Water Supply , 2016, 16(6): 1552-1560.

DOI：10.2166/ws.2016.068

• cyanobacteria
• gas vacuoles
• high pressure
• Microcystis aeruginosa
• Pseudanabaena galeata
• settling velocity

This study estimated the ability of pressurization to collapse gas vesicles and thereby enhance the settleability of freshwater cyanobacteria. Settling velocities of Pseudanabaena galeata and Microcystis aeruginosa were measured at 11 different pressure values from 0 to 0.5 MPa. The morphological variations that occurred in the gas vacuoles according to the applied pressure were investigated using transmission electron microscopy images. The settleability of both cyanobacteria species increased statistically significantly (P = 0.000) with increasing pressure, whereas the gas-vacuolated area of both species decreased significantly (P = 0.000) with the magnitude of the applied pressure. The removal ability of cyanobacterial cells from the water layer increased with high pressure treatment. The maximum removal efficiency observed of P. galeata and M. aeruginosa cells relative to the control culture were 82% and 95%, respectively, at the maximum tested pressure value of 0.5 MPa.

• 出版日期2016-12