This study estimated the ability of pressurization to collapse gas vesicles and thereby enhance the settleability of fresh water 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.
An alternative method to improve the settleability of gas-vacuolated cyanobacteria by collapsing gas vesicles
Helayaye Damitha Lakmali Abeynayaka, Takashi Asaeda, Kyoko Tanaka, Kimie Atsuzawa, Yasuko Kaneko, Hidenori Nishda, Seiichi Inada; An alternative method to improve the settleability of gas-vacuolated cyanobacteria by collapsing gas vesicles. Water Supply 1 December 2016; 16 (6): 1552–1560. doi: https://doi.org/10.2166/ws.2016.068
Download citation file: