2022 Volume 58 Issue 2 Pages 83-92
The characteristics of vegetative cell growth and akinete formation in the cyanobacterium Dolichospermum planctonicum were examined using three different media (WC, CB, and CT media), and two different methods for the recovery of akinetes, i.e. the lysozyme method and the sedimentation-separation method, were compared to evaluate which way was efficient. The equilibrium vegetative cell and akinete density were higher for the WC medium than those for the CB and CT media (p < 0.05), exhibiting ca. 1.23 × 107 ± 1.58 × 106 cells・mL－1 and 1.60 × 104 ± 3.46 × 103 akinetes・mL－1, respectively. These results suggest that the WC medium was appropriate for the cultivation of D. planctonicum. The lysozyme method and the sedimentation-separation method using a separatory funnel were compared to recover the akinetes of D. planctonicum. The results showed that the former method was found to be more successful in separating the akinetes from the vegetative cells, and the recovery rate was also higher (the lysozyme method: 66.7%, the sedimentation-separation method: 55.0%). The results obtained in the present study would be useful to elucidate the mechanisms of akinete germination and/or akinete recruitment from sediment, which could contribute to suppress the cyanobacterial bloom occurrence in the eutrophic lakes.
