Zigui Ecological Station for Three Gorges Dam Project, State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, 71 East Beijing Road, Nanjing 210008, China; College of Advanced Agricultural Science, University of Chinese Academy of Sciences, Beijing 100049, China.
Zigui Ecological Station for Three Gorges Dam Project, State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, 71 East Beijing Road, Nanjing 210008, China; Agricultural Service Center of Qiandeng Town, 442 North Jingtang Road, Qiandeng Town, Kunshan 215300, China.
Bioresour Technol. 2020 May;303:122922. doi: 10.1016/j.biortech.2020.122922. Epub 2020 Jan 29.
Due to its extensive application in agriculture as a germinating agent and growth promoter, indole acetic acid (IAA) is present in a variety of aquatic ecosystems. To explore the response of microbial aggregates to exogenous IAA in aquatic ecosystems, periphytic biofilm, a typical microbial aggregate, was exposed to IAA at different concentrations. Results reveal an unexpected concentration-dependent effect of IAA on periphytic biofilm. Concentrations of IAA less than 10 mg/L inhibit periphytic growth, but stimulate growth when the IAA concentration exceeds 50 mg/L. Periphytic biofilm adapts to different IAA concentrations by antioxidant enzyme activation, community structure optimization and carbon-metabolism pattern change, and promotes bioremediation of IAA contaminated water in the process. The removal rates of IAA reached up to 95%-100%. This study reveals the capacity of periphytic biofilm for IAA removal in practice.
由于吲哚乙酸 (IAA) 在农业中作为发芽剂和生长促进剂的广泛应用，它存在于各种水生生态系统中。为了探究微生物聚集体对水生生态系统中外源 IAA 的响应，采用附着生物膜（一种典型的微生物聚集体）作为研究对象，在不同浓度的 IAA 下进行暴露实验。结果表明，IAA 对附着生物膜表现出了出乎意料的浓度依赖性效应。IAA 浓度低于 10mg/L 时会抑制附着生物膜的生长，但当 IAA 浓度超过 50mg/L 时，会刺激其生长。附着生物膜通过激活抗氧化酶、优化群落结构和改变碳代谢模式来适应不同的 IAA 浓度，并在这个过程中促进了 IAA 污染水的生物修复。IAA 的去除率高达 95%-100%。本研究揭示了附着生物膜在实际应用中去除 IAA 的能力。
