Lü Ping, Li Hui-Li, Xu Yong, Zheng Xiao-Xu, Huang Zhen-Hua, Wang Cong, Xu Sheng-Jun, Zhuang Xu-Liang
School of Civil Engineering, Lanzhou University of Technology, Lanzhou 730050, China.
Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
Huan Jing Ke Xue. 2022 Oct 8;43(10):4502-4510. doi: 10.13227/j.hjkx.202201159.
The "bacteria-algae" system plays an important role in water ecosystems. The effects of bacteria in phycospheres on the growth of under in-situ nutrient stimulation were studied to explore the bacteria-algae interaction during a cyanobacteria bloom. The results showed that LB medium could inhibit the growth of , and the algicidal rate was 86.49%. Sodium acetate, glucose, and sodium citrate could promote , and the growth rate was more than 50%. The addition of nutrients in could have changed the biocoenosis in the phycosphere and increased the species richness by 16S rRNA gene sequencing, and the number of bacteria in the phycosphere increased dramatically in the LB medium and peptone groups. The physiological and biochemical responses showed that algae suffered serious lipid peroxidation, and superoxide dismutase (SOD) and catalase (CAT) activities first increased significantly and subsequently decreased under the oxidative stress of LB medium or peptone. Scanning electron microscopy (SEM) indicated that the surface of algae cells appeared wrinkled, invaded, and atrophied under LB medium stimulation, whereas bacteria in the phycosphere significantly increased. Furthermore, six strains of algicidal bacteria were isolated from the LB medium and peptone groups, and the algicidal rate of sp. A1 was 97.55%, which confirmed that the phycosphere of included algicidal bacteria. Therefore, appropriate external nutrient stimulation can produce algicidal bacteria in situ to prevent cyanobacterial blooms.
“细菌-藻类”系统在水生态系统中发挥着重要作用。研究了藻际中细菌在原位营养刺激下对[藻类名称未给出]生长的影响，以探讨蓝藻水华期间的细菌-藻类相互作用。结果表明，LB培养基可抑制[藻类名称未给出]的生长，杀藻率为86.49%。醋酸钠、葡萄糖和柠檬酸钠可促进[藻类名称未给出]生长，生长速率超过50%。通过16S rRNA基因测序，[藻类名称未给出]中添加营养物质可能改变了藻际生物群落，增加了物种丰富度，并且在LB培养基和蛋白胨组中藻际细菌数量显著增加。生理生化反应表明，在LB培养基或蛋白胨的氧化应激下，藻类遭受严重的脂质过氧化，超氧化物歧化酶（SOD）和过氧化氢酶（CAT）活性先显著升高，随后降低。扫描电子显微镜（SEM）表明，在LB培养基刺激下，藻细胞表面出现褶皱、入侵和萎缩，而藻际中的细菌显著增加。此外，从LB培养基和蛋白胨组中分离出6株杀藻细菌，其中[细菌名称未给出]sp. A1的杀藻率为97.55%，证实[藻类名称未给出]的藻际中存在杀藻细菌。因此，适当的外部营养刺激可原位产生杀藻细菌以预防蓝藻水华。
