摘要
“菌-藻”体系在水生态平衡中发挥重要作用,为探明蓝藻水华时期的菌藻关系,研究了原位营养刺激后藻际微生物对铜绿微囊藻生长的影响.结果表明,LB培养基可抑制铜绿微囊藻生长,抑藻率为86.49%;而乙酸钠、葡萄糖和柠檬酸钠可促进藻细胞生长,增长率均在50%以上.对LB培养基和蛋白胨刺激后的藻际细菌进行溶藻菌的筛选,共分离出6株具有强效抑藻作用的菌株,其中Bacillus sp. A1抑藻率高达97.55%. 16S rRNA高通量测序表明,向铜绿微囊藻中投加营养物质均可改变藻际细菌群落结构并增加物种丰富度,添加LB培养基和蛋白胨可促使藻际细菌群落数量剧增.生理生化响应表明,藻细胞受LB培养基和蛋白胨胁迫后,活性氧(ROS)水平和丙二醛(MDA)含量激增,细胞氧化损伤严重;超氧化物歧化酶(SOD)、过氧化氢酶(CAT)活性先急剧上升后下降,抗氧化酶系统受损.扫描电镜显示,LB培养基可使藻细胞逐渐萎缩,最终破碎;而藻际细菌显著增多.因此,在蓝藻水华暴发的水体进行适当的外部营养刺激可在一定程度上实现溶藻菌原位抑藻.
The “bacteria-algae” system plays an important role in water ecosystems. The effects of bacteria in phycospheres on the growth of Microcystis aeruginosa 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 M. aeruginosa, and the algicidal rate was 86.49%. Sodium acetate, glucose, and sodium citrate could promote M. aeruginosa, and the growth rate was more than 50%. The addition of nutrients in M. aeruginosa could have changed the biocoenosis in the phycosphere and increased the species richness by 16 S 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 Bacillus sp. A1 was 97.55%, which confirmed that the phycosphere of M. aeruginosa included algicidal bacteria. Therefore, appropriate external nutrient stimulation can produce algicidal bacteria in situ to prevent cyanobacterial blooms.
作者
吕萍
李慧莉
徐勇
郑效旭
黄振华
王聪
徐圣君
庄绪亮
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;Feixian Branch of Linyi Ecological Environmental Bureau,Linyi 273400,China;Yangtze River Delta Research Center for Eco Environmental Sciences,Yiwu 322000,China)
出处
《环境科学》
EI
CAS
CSCD
北大核心
2022年第10期4502-4510,共9页
Environmental Science
基金
中国科学院长三角中心重点部署项目(20190627)。
关键词
蓝藻水华
铜绿微囊藻
藻际环境
菌藻关系
溶藻细菌
抗氧化酶活性
cyanobacterial bloom
Microcystis aeruginosa
phycosphere
algal-bacterial interaction
algicidal bacteria
antioxidant enzyme system
