CAREER: PFAS-BioAction: Innovative treatment of municipal solid waste organics through insect-mediated bioprocessing and sequestration of poly- and perfluoroalkyl substances

食物和有机废物是填埋场城市固体废物的最大组成部分。2018年，超过3000万吨食品和有机废物被填埋。填埋的有机废物的管理具有挑战性，因为它往往需要设计和整合处理列车，以控制气味排放和有毒沥滤液以及二氧化碳和甲烷等温室气体的释放。昆虫介导的生物转化（IMB）已成为一个有前途的和可持续的替代食品/有机废物转化为有用的产品。IMB的基本前提是，食物/有机废物可用作培养昆虫的基质，然后可加工成有价值的产品，包括动物饲料，生物燃料和堆肥或更高价值的土壤改良剂。 该CAREER项目的总体目标是探索使用IMB来隔离和降解持久性和有毒污染物，最初重点是填埋有机废物中的聚和全氟烷基物质（PFAS）。 为了推进这一目标，主要研究者建议使用黑水虻幼虫（BSFL）作为模型系统来研究PFAS如何在昆虫中积累以及昆虫肠道中酶降解PFAS的程度。 该项目的成功完成将通过产生新的基础知识来促进IMB作为PFAS污染的填埋有机废物的可持续处理技术的发展，从而造福社会。通过学生教育和培训，包括指导加州大学戴维斯分校的一名研究生和一名本科生，将进一步造福社会。昆虫介导的生物转化（IMB）已成为一个有前途的、可扩展的和具有成本效益的平台，从有机废物流中产生有价值的产品。然而，很少有人知道IMB的潜力，以处理和降解持久性和有毒的污染物，如PFAS，往往存在于填埋的有机废物。 这个CAREER项目建议调查PFAS的生物积累和生物转化的黑色士兵蝇幼虫（BSFL），一个家庭的昆虫具有很大的潜力，转化有机废物为有用的产品，由于其高脂质和蛋白质含量。本研究的两个主要目的是：1）探索PFAS与模型脂质和蛋白质的相互作用，以揭示PFAS在昆虫组织中的生物积累机制; 2）评估PFAS在BSFL中的生物积累、代谢和生物转化程度。为了推进这些目标，主要研究者（PI）建议开展一项综合实验和建模研究计划，该计划将联合收割机1）液相色谱四极杆飞行时间质谱（LC-QTOF-MS），并进行针对性分析，以评估转移的食物垃圾、成品堆肥和垃圾渗滤液中PFAS的丰度和多样性，2）使用人血清白蛋白作为模型系统预测PFAS与蛋白质的结合亲和力的原子分子动力学（MD）模拟，3）测量PFAS在BSFL组织匀浆的蛋白质和脂质级分中的生物累积的离体测定，和4）测量和表征PFAS在BSFL组织中的生物积累和生物转化的实验测定。该项目的成功完成有可能通过产生新的基础知识来推动IMB作为一种高效且具有成本效益的PFAS修复技术的开发和实施，从而产生变革性影响。为了实现这个职业项目的教育和培训目标，PI将修改她在加州大学戴维斯分校的本科课程之一，包括一个CURES（基于课程的本科生研究经验）模块，该模块将通过一个完整的调查周期吸引三到四名学生组成的团队，从开发一个研究问题和一个与PFAS等污染物生物累积相关的可测试假设开始。此外，PI计划积极与工程教育工作者和专业人士合作，传播教育资源，分享她的CAREER项目的关键研究成果，并促进围绕实现零废物未来的科学解决方案进行有意义的对话。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Food and organic wastes are the largest component of municipal solid waste in landfills. In 2018, over 30 million tons of food and organic wastes were disposed of in landfills. The management of landfilled organic wastes is challenging as it often requires the design and integration of treatment trains to control odor emissions and the release of toxic leachates and greenhouse gases such as carbon dioxide and methane. Insect mediated bioconversion (IMB) has emerged as a promising and sustainable alternative to convert food/organic wastes to useful products. The basic premise of IMB is that food/organic wastes can be used as substrates to grow insects which can then be processed into valuable products including animal feed, biofuels, and compost or higher-value soil amendments. The overarching goal of this CAREER project is to explore the use of IMB to sequester and degrade persistent and toxic contaminants with an initial focus on poly- and perfluoroalkyl substances (PFAS) from landfilled organic wastes. To advance this goal, the Principal Investigator proposes to use the black soldier fly larvae (BSFL) as model systems to investigate how PFAS accumulate in insects and the extent of PFAS degradation by enzymes in insect guts. The successful completion of this project will benefit society through the generation of new fundamental knowledge to advance the development of IMB as a sustainable treatment technology for PFAS-contaminated landfilled organic wastes. Further benefits to society will be achieved through student education and training including the mentoring of a graduate student and an undergraduate student at the University of California, Davis.Insect-mediated bioconversion (IMB) has emerged as a promising, scalable, and cost-effective platform to generate valuable products from organic waste streams. However, little is known about the potential of IMB to treat and degrade persistent and toxic contaminants such as PFAS that are often present in landfilled organic wastes. This CAREER project proposes to investigate the bioaccumulation and biotransformation of PFAS by black soldier fly larvae (BSFL), a family of insects with great potential to convert organic wastes to useful products due to their high lipids and protein contents. Two key goals of the research are to: 1) probe PFAS interactions with model lipids and proteins to unravel the mechanisms of PFAS bioaccumulation in insect tissues and 2) evaluate the extents of PFAS bioaccumulation, metabolism, and bioconversion by BSFL. To advance these goals, the Principal Investigator (PI) proposes to carry out an integrated experimental and modeling research program that will combine 1) liquid-chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) with targeted analysis to evaluate the abundance and diversity of PFAS in diverted food waste, finished compost, and landfill leachate, 2) atomistic molecular dynamics (MD) simulations to predict the binding affinities of PFAS to proteins using human serum albumin as model system, 3) ex vivo assays to measure PFAS bioaccumulation in the protein and lipid fractions of BSFL tissue homogenates, and 4) experimental assays to measure and characterize PFAS bioaccumulation and biotransformation in the tissues of BSFL. The successful completion of this project has the potential for transformative impact through the generation of new fundamental knowledge to advance the development and implementation of IMB as an efficient and cost-effective PFAS remediation technology. To implement the educational and training goals of this CAREER project, the PI will revise one of her undergraduate courses at UC-Davis to include a CURES (course-based undergraduate research experiences) module that will engage teams of three to four students through a complete inquiry cycle, beginning with the development of a research question and a testable hypothesis linked to the bioaccumulation of contaminants such as PFAS. In addition, the PI plans to actively engage with engineering educators and professionals to disseminate educational resources, share key research findings from her CAREER project, and promote meaningful dialogue around science-based solutions for achieving a zero-waste future.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.