GOALI/Collaborative: Engineering Biofilm Dynamics for Cyanotoxins in Biological Water Treatment

有害藻华发生的频率和持续时间的增加，对饮用水供应的威胁在全国和全球范围内都呈上升趋势，例如伊利湖的蓝藻华。为了保护公众免受饮用水源中出现的蓝藻毒素等污染物的侵害，自来水公司考虑并采用了各种先进的水处理工艺。该项目正在探索一种可持续的处理方法，使用细菌活性过滤器去除有害的藻华毒素和其他新出现的化学物质，作为饮用水处理的第一步。然而，对于新出现的污染物，生物过滤系统并没有得到很好的采用，因为它们通常对目标污染物表现出较低或无法维持的生物膜活性。为了提高生物过滤系统的性能，考虑了生物增强和生物刺激，但仍然被认为是不可控的工程方法，以获得一致的结果。因此，需要系统的研究来了解和控制生物过滤系统中新兴污染物的生物膜动力学。本研究的主要研究目标是：1)了解生物膜群落的组成、活性和动态及其对生物过滤系统去除蓝藻毒素效果的影响；2)在被有害藻华生物污染的水源压力下，为生物过滤系统的有效运行提供最佳操作参数和监测工具。研究重点将放在了解如何通过生物增强和生物刺激等工程方法来增强和维持细菌生物膜的形成和活性，以提高生物过滤系统去除蓝藻毒素的性能。提出的具体目标和假设是：1)了解蓝藻毒素降解细菌的降解动力学（适应和进化），用于生物增强或生物刺激应用。假设：水体中蓝藻毒素的浓度变化以及其他天然有机物和营养物的存在会影响蓝藻毒素降解菌的群落和功能。2)研究生物增强细菌与过滤介质上形成的本地生物膜之间的表面相互作用（微生物生物膜的物理、化学和生物介导的相互作用）。假设：生物膜的形成不仅会影响生物过滤系统的流体动力学和物理性质（如介质的有效尺寸），还会影响生物增强细菌在生物过滤系统中的粘附和生长。3)确定过滤器操作参数对生物过滤系统中生物膜的形成、生长和随后的蓝藻毒素降解的影响。假设：可以获得生物过滤系统的优化运行参数（反冲洗频率和强度、过滤速率、生物刺激），以应对各种环境因素。此外，拟议的项目将为三名研究生提供培训和教育，并为本科生和高中生提供暑期研究机会。此外，研究成果将被引入pi的外展和服务活动中，例如，针对代表性不足的K-12学生的教育计划和通过伊利湖中心进行的公众外展。

1605185/1605161Seo / MouThreats to drinking water supplies as a result of increased frequency and duration of harmful algal blooms has been on the rise nationally and globally, for example the Lake Erie cyanobacteria bloom. To protect the public from emerging contaminants like cyanotoxins in drinking water sources, various advanced water treatment processes are considered and adopted by water utilities. This project is exploring a sustainable treatment approach using bacterially active filters to remove harmful algal bloom toxins and other chemicals of emerging concern as the first step in drinking water treatment. However, biological filtration systems for emerging contaminants are not well adopted as they commonly show either low or unmaintained biofilm activities for target pollutants. To enhance the performance of biological filtration systems, bioaugmentation and bio-stimulation were considered, but still regarded as uncontrollable as engineering approaches for consistent results. Accordingly, systematic studies are greatly needed to understand and control biofilm dynamics in biological filtration systems for emerging contaminants. The principal research objectives of this study are: 1) to understand the composition, activity and dynamics of biofilm community and their impact on the effectiveness of biological filtration systems in cyanotoxin removal, and, 2) to provide optimum operational parameters and monitoring tools for effective biological filtration systems operations under the pressure of source water contaminated with harmful algal bloom organisms. Research emphasis will be placed on understanding how the bacterial biofilm formation and activity, can be enhanced and maintained by engineered approaches such as bioaugmentation and bio-stimulation in order to improve performances of biological filtration systems for cyanotoxin removal. Specific objectives and hypotheses proposed are: 1) To understand the degradation dynamics (adaptation and evolution) of cyanobacteria toxin degrading bacteria for bioaugmentation or bio-stimulation applications. Hypothesis: The concentration variation of cyanotoxins and the presence of other natural organic matter and nutrients in water will affect the community and function of cyanotoxin degrading bacteria. 2) To investigate surface interactions between bioaugmented bacteria and indigenous biofilm formed on filter media (physical, chemical, and biologically mediated interactions by microbial biofilms). Hypothesis: The formation of biofilm(s) may affect not only hydrodynamics and physical properties (e.g. effective size of media) of biological filtration systems, but also the adhesion and growth of bioaugmented bacteria in biological filtration systems. 3) To determine the impact of filter operational parameters on biofilm formation, growth, and subsequent degradation of cyanotoxins in biological filtration systems. Hypothesis: Optimized operational parameters of biological filtration systems (backwashing frequency and intensity, filtration rate, and bio-stimulation) can be obtained to address various environmental factors. In addition, the proposed project will provide training and education for three graduate students as well as summer research opportunities for undergraduate and high school students. Furthermore, research findings will be introduced in PIs' outreach and service activities, for example, educational programs for under-represented K-12 students and public outreach via Lake Erie Center.