College of Environmental Science and Engineering, Donghua University, Shanghai, People's Republic of China.
Shanghai Institute of Pollution control and Ecological Security, People's Republic of China.
Environ Technol. 2022 Nov;43(27):4341-4353. doi: 10.1080/09593330.2021.1949047. Epub 2021 Jul 8.
Application of algicidal bacteria is a promising technology to control harmful algal blooms (HABs). In this study, algicidal bacteria strains sp. H3 and sp. H5 were obtained via two different isolation methods from the same lake water sample, with optimal algicidal efficiencies 96% and 74% against algae mixture. The sp. H3 and sp. H5 lysed algae cells through cells-to-cells direct contact and secretion of algicidal metabolites, respectively. The stronger algicidal capability of sp. H3 was also attributable to its higher efficiency for triggering reactive oxygen species, which led to broken down of the antioxidant system and more severe damage to the bacterial cells. The antioxidant enzyme activities in sp. H5 group were still expressed because of its relatively weaker algicidal capability and some intact algal cells were remained. The liquid carbohydrates from algal lysis in both groups increased significantly, whereas the quantities of liquid protein decreased, which might be assimilated by algicidal bacteria. Nonetheless, the whole algicidal process resulted in the increase of total released organic matters content. This study revealed the algicidal pathways of diverse bacterial strains, and the possible secondary environmental problem caused by the algal released organic matters should be considered when applying bacteria to control HABs.
应用杀藻细菌是控制有害藻华（HAB）的一种有前途的技术。在这项研究中，通过两种不同的分离方法从同一样品水中获得了杀藻细菌菌株 sp. H3 和 sp. H5，对藻类混合物的最佳杀藻效率分别为 96%和 74%。sp. H3 和 sp. H5 通过细胞间直接接触和分泌杀藻代谢物分别裂解藻类细胞。sp. H3 更强的杀藻能力还归因于其触发活性氧的效率更高，这导致抗氧化系统崩溃和细菌细胞受到更严重的损伤。由于其较弱的杀藻能力，sp. H5 组中的抗氧化酶活性仍在表达，并且仍然存在一些完整的藻类细胞。两组的液体碳水化合物从藻类裂解中显著增加，而液体蛋白质的数量减少，这可能被杀藻细菌同化。然而，整个杀藻过程导致总释放有机物质含量增加。本研究揭示了不同细菌菌株的杀藻途径，在应用细菌控制 HAB 时，应考虑由藻类释放的有机物质可能引起的二次环境问题。
