Xu Li’s research revolves around microbes important to environment quality and public health. By working at the interface of environmental engineering and applied microbiology, his research group aims to advance knowledge on microbial communities relevant to contaminant biotransformation, resource recovery, and antibiotic resistance. He develops technologies and interventions to prevent and minimize pollution of water, soil, and crops and to protect human health from pollution. Specifically, he designs and optimizes engineering systems for drinking water treatment, wastewater reuse, and stormwater management, as well as agricultural practices for manure storage and land application.

Honors and Awards

Holling Family Distinguished Senior Faculty Teaching Award, College of Engineering, UNL, 2020
Dean’s Award for Excellence in Graduate Education, Office of Graduate Studies, UNL, 2019
Faculty Research and Creative Activity Award, College of Engineering, UNL, 2019 (as an associate professor) and 2013 (as an assistant professor)
Henry Y. Kleinkauf Family Distinguished New Faculty Teaching Award, College of Engineering, UNL, 2015
Edgerton Innovation Award, College of Engineering, UNL, 2015
Grand Prize for Excellence in Environmental Engineering and Science (E3S) award under the University Research category, American Academy of Environmental Engineers and Scientists (AAEES), 2015
CAREER Award, National Science Foundation, 2014
Maher and Lorees Tadros Faculty Recognition Award, Department of Civil Engineering, UNL, 2014
Visiting professor, Department of Civil and Environmental Engineering, National University of Singapore, May-June 2013
Olsson and Associates Faculty Teaching Excellence Award, Department of Civil Engineering, UNL, 2013

Selected Publications

Mohammadreza Shafieifini, Yuepeng Sun, Zachery Staley, Jean-Jack Riethoven, and Xu Li. 2022. Effects of nutrient level and growth rate on the conjugation process that transfers mobile antibiotic resistance genes in continuous cultures. Applied and Environmental Microbiology, in press.
Bo Li, Xu Li, Bing Wang, and Tao Yan. 2022. A metagenomic approach for characterizing antibiotic resistance genes in specific bacterial populations: demonstration with Escherichia coli in cattle manure. Applied and Environmental Microbiology, 88(7):e0255421.
Noelle A. Mware, Maria C. Hall, Selvakumar Rajendran, John E. Gilley, Amy M. Schmidt, Shannon L. Bartelt-Hunt, Yifan Zhang, and Xu Li. 2022. Resistome and mobilome in runoff from manured soil as affected by setback distance. Journal of Hazardous Materials, 429: 128278.
Ting He, Jianguo Bao, Yifei Leng, Shuqiong Kong, Jiangkun Du, and Xu Li. 2022. Rice straw particles covered with Brevundimonas naejangsanensis DD1 cells can synergistically remove doxycycline from water using adsorption and biotransformation. Chemosphere, 291: 132828.
Renys Barrios, Chin Lim, Megan Kelley, and Xu Li. 2021. SARS-CoV-2 concentrations in a wastewater collection system revealed hotspots at the zip code level. Science of the Total Environment, 800: 149480.
Yuepeng Sun, Daniel Snow, Harkamal Walia, and Xu Li. 2021. Transmission routes of microbiome and resistome from manure to soil and lettuce. Environmental Science and Technology, 55 (16): 11102-11112.
Yuepeng Sun, Bertrand Clarke, Jennifer Clarke, and Xu Li. 2021. Predicting antibiotic resistance gene abundance in activated sludge using shotgun metagenomics and machine learning. Water Research, 202:117384.
Zachery R. Staley, Bryan L. Woodbury, Bobbi S. Stromer, Amy M. Schmidt, Daniel D. Snow, Shannon Bartelt-Hunt, Bing Wang, and Xu Li. 2021. Stockpiling versus composting: Effectiveness in reducing antibiotic-resistant bacteria and resistance genes in beef cattle manure. Applied and Environmental Microbiology, 87 (16): 10.1128/AEM.00750-21
Ting He, Jianguo Bao, Yifei Leng, Daniel Snow, Shuqiong Kong, Tong Wang, and Xu Li. 2021. Biotransformation of doxycycline by Brevundimonas naejangsanensis and Sphingobacterium mizutaii strains. Journal of Hazardous Materials, 411:125126.
Zach R. Staley, Christopher Y. Tuan, Kent M. Eskridge, and Xu Li. 2021. Using the heat generated from electrically conductive concrete slabs to reduce antibiotic resistance in beef cattle manure. Science of the Total Environment, 768:144220.
Maria C. Hall, Jon Duerschner, John Gilley, Amy Schmidt, Shannon Bartelt-Hunt, Daniel Snow, Kent Eskridge, and Xu Li. 2021. Antibiotic resistance genes in swine manure slurry as affected by pit additives and facility disinfectants. Science of the Total Environment, 761:143287.
Shahab Karimifard, Xu Li, Christian Elowsky, and Yusong Li. 2021. Modeling the impact of evolving biofilms on flow in porous media inside a microfluidic channel. Water Research, 188:116536.
Maria Cecilia Hall, Noelle A. Mware, John E. Gilley, Shannon Bartelt-Hunt, Daniel D. Snow, Amy M. Schmidt, Kent M. Eskridge, and Xu Li. 2020. Influence of setback distance on antibiotics and antibiotic resistance genes in runoff and soil following the land application of swine manure slurry. Environmental Science and Technology, 54 (8): 4800-4809.
Renys Barrios, Himanshu Khuntia, Shannon Bartelt-Hunt, John Gilley, Amy Schmidt, Daniel Snow, and Xu Li. 2020. Fate and transport of antibiotics and antibiotic resistance genes in runoff and soil as affected by the timing of swine manure slurry application. Science of the Total Environment, 712: 136505.
Zachary R. Staley, Amy Millmier Schmidt, Bryan Woodbury, Kent M. Eskridge, Lisa Durso, and Xu Li. 2019. Corn stalk residue may add antibiotic resistant bacteria to manure composting piles. Journal Environmental Quality, 49 (3): 745-753.
Baral, D., B. Dvorak, A. Admiraal, S. Jia, C. Zhang, and X. Li. 2018. Tracking the sources of antibiotic resistance genes in an urban stream during wet weather using shotgun metagenomic analyses. Environmental Science and Technology. 52 (16): 9033-9044.
Zhang, Y., C. Jewett, J. Gilley, S. Bartelt-Hunt, D. Snow, L. Hodges, and X. Li. 2018. Microbial communities in the rhizosphere and the root of lettuce as affected by contaminated irrigation water. FEMS Microbial Ecology, 94 (9). DOI: 10.1093/femsec/fiy135.
Baral, D., A. Speicher, B. Dvorak, D. Admiraal, and X. Li. 2018. Quantifying the relative contributions of environmental sources to the microbial community in an urban stream under dry and wet weather conditions. Applied and Environmental Microbiology, 84 (15): e00896-18.
Leng, Y., J. Bao, D. Song, J. Li, M. Ye, and X. Li. 2017. Background nutrients affect tetracycline biotransformation by Stenotrophomonas maltophilia as revealed by genomics and proteomics. Environmental Science and Technology, 51: 10476-10484.
Du, Z., Y. Chen, and X. Li. 2017. Quantitative proteomic analyses of the microbial degradation of estrone under various background nitrogen and carbon conditions. Water Research, 123: 361-368.
Leng, Yifei, Jianguo Bao, Gaofeng Chang, Han Zhang, Xingxing Li, Jiangkun Du, Daniel Snow, and X. Li. 2016. Biotransformation of tetracycline by a novel bacterial strain Stenotrophomonas maltophilia DT1. Journal of Hazardous Materials, 318: 125-133.
Zhang, Y.^#, Sallach, J.B.^#, L. Hodges, D. Snow, S. Bartelt-Hunt, K. Eskridge, and X. Li. 2016. Effects of soil texture and drought stress on the update of antibiotics and the internalization of Salmonella in lettuce following wastewater irrigation. Environmental Pollution, 208: 523-531. (^# equal contribution)
Sallach, J.B., D. Snow, L. Hodges, X. Li, and S. Bartelt-Hunt. 2016. Development and comparison of four methods for the extraction of antibiotics from a vegetative matrix. Environmental Toxicology and Chemistry, 35: 889-897.
Du, Z., D. Riveros-Iregui, R. Jones, T. McDermott, J. Dore, B. McGlynn, R. Emanuel, and X. Li. 2015. Landscape position influences microbial composition and function via redistribution of soil water across a watershed. Applied and Environmental Microbiology, 81: 8457-8468.
Soni, B., S. Bartelt-Hunt, D. Snow, J. Gilley, B. Woodbury, D. Marx, and X. Li. 2015. Narrow grass hedges reduce tylosin and associated resistance genes in agricultural runoff. Journal of Environmental Quality, 44: 895-902.
Du, Z., R. Nandakumar, K. Nickerson, and X. Li. 2015. Proteomic adaptations to starvation prepare Escherichia coli for disinfection tolerance. Water Research, 69: 110-119.
Sallach, J.B.^#, Zhang, Y.^#, D. Snow, L. Hodges, X. Li, and S. Bartelt-Hunt. 2014. Concomitant uptake of antimicrobials and Salmonella in soil and into lettuce following wastewater irrigation. Environmental Pollution, 197: 269-277. (^# equal contribution)
Joy, S., X. Li, D. Snow, J. Gilley, B. Woodbury, and S. Bartelt-Hunt. 2014. Fate of antimicrobials and antimicrobial resistance genes in simulated swine manure storage. Science of the Total Environment, 481: 69-74.
Zhang, Y., R. Nandakumar, S. Bartelt-Hunt, D. Snow, L. Hodges, and X. Li. 2014. Quantitative proteomic analysis of the Salmonella-lettuce interaction. Microbial Biotechnology, 7(6): 630-637.
Joy, S., S. Bartelt-Hunt, J. Gilley, D. Snow, D. Parker, B. Woodbury, D. Marx, and X. Li. 2013. Fate and transport of antimicrobials and antimicrobial resistance genes in soil and runoff following land application of swine manure slurry. Environmental Science and Technology, 47 (21): 12081-12088.
Zhang, Y., D. Snow, D. Parker, Z. Zhou, and X. Li. 2013. Intracellular and extracellular antimicrobial resistance genes in livestock waste management structures. Environmental Science and Technology, 47(18): 10206-10213.
Zhang, Y., C. Zhang, D. Snow, D. Parker, Z. Zhou and X. Li. 2013. Occurrence of antimicrobials and antimicrobial resistance genes in beef cattle storage ponds and swine treatment lagoons. Science of the Total Environment, 463-464: 631-638.
Li, Z., N. Madayiputhiya, R. Nandakumar, and X. Li. 2012. Proteomic analysis of 17β-estradiol degradation by Stenotrophomonas maltophilia. Environmental Science and Technology, 46: 5947-5955.
Li, Z., B. Dvorak, and X. Li. 2012. Removing 17β-estradiol using a biologically active reactor (BAC) reactor modified from a granular activated carbon (GAC) reactor. Water Research, 46: 2828-2836.
Li, X., W. Yuen, E. Morgenroth, and L. Raskin. 2012. Backwash intensity and frequency impact the microbial community structure and function in a fixed-bed biofilm reactor. Applied Microbiology and Biotechnology, 96: 815-827.
Li, X., G. Upadhyaya, W. Yuen, J. Brown, E. Morgenroth, and L. Raskin. 2010. Changes in microbial community structure and function of drinking water treatment bioreactors upon phosphorus addition. Applied and Environmental Microbiology, 76: 7473-7481.
Li, X., E. Morgenroth, and L. Raskin. 2008. Quantitative rRNA-targeted solution-based hybridization assay using peptide nucleic acid molecular beacon. Applied and Environmental Microbiology, 74: 7297-7305.
Choi, Y-C., X. Li, L. Raskin, and E. Morgenroth. 2008. Chemisorption of oxygen onto activated carbon can enhance the stability of biological perchlorate reduction in fixed bed biofilm reactors. Water Research, 42: 3425-3434.
Choi, Y-C., X. Li, L. Raskin, and E. Morgenroth. 2007. Effect of backwashing on perchlorate removal in fixed bed biofilm reactors. Water Research, 41: 1949-1959.
Li, X. and B. Logan. 2004. Analysis of bacterial adhesion using a gradient force analysis and colloid probe atomic force microscopy. Langmuir, 20: 8817-8822.