My research focuses on microbes involved in anaerobic degradation and biogas production. I am particularly interested in discovering co-occouring network and syntrophic interactions, with the aim to find microbial solutions combined with technological innovations to increase and stabilize biogas production. My prospect is to deepen the knowledge and contribute to the development of anaerobic digestion processes that can be used to build biomass-based platforms for production of biofuels and bio-fertilizer. I've an expertise in strict anaerobic cultivation techniques, bioreactor operation and molecular analyses. As a member of the Anaerobic Microbial Biotechnology (AMB) at SLU, I perform research in close collaboration with biogas industry, research institutes and other Swedish and international research groups.
I started my doctoral studies in 2007 after finishing my MSc in Biotechnology at the Lund Univeristy. I recieved my PhD 2012 with the thesis “Biogas production through the syntrophic acetate-oxidising pathway – characterisation and detection of syntrophic acetate-oxidising bacteria”. I have since then worked as a researcher with a break in 2015 when I did a postdoc at the university KU Leuven in Belgium.
Biogas production in a sustainable society, anaerobic microbiology, microbial energy metabolism
European Research Council (ERC) Starting Grant 2020. ”Deciphering the network of microbial, environmental and physical factors underlying aggregation and enhanced performance in syntrophic microorganism communities” Grant No 948138. Project investigator
Kamprad Family Foundation. "Unique reactor concept for enhanced biogas production from lignocellulosic material". Grant No 20200126. Main applicant
Vetenskapsrådet (VR) Starting Grant (NE). “Promote syntrophic flocculation for optimization of microbial processes” Grant No 2019-03846. Main applicant
Forskningsråd för hållbar utveckling (Formas). Research and development projects for future research leaders 2018. “Improved biogas production by promoting syntrophic propionate oxidation” Grant No 2018-00928. Main applicant.
Formas Research and development projects 2018. “Acetogenic platform for production of green bulk chemical”. Grant No 2018-01341. Co-applicant.
Award in the technical-economic class by the Royal Society of Sciences in Uppsala, Sweden. “For outstanding research on syntrophic anaerobic microorganisms”
Initiator and participant of the cooperation project "Optimal operating temperature for solid degradation food waste" with Swedish Environmental Research Institute (IVL) and Research Institutes of Sweden (RISE). Funded by Energiforsk BfS2030.
2021 - Supervisor, PhD student Eduardo Pinela, Molecular Sciences, SLU
2021 - Supervisor, PhD student Nils Weng, Molecular Sciences, SLU
2020 – Co-supervisor, PhD student George Cheng, Molecular Sciences, SLU
2020 – Co-supervisor, PhD student Ebba Perman, Molecular Sciences, SLU
2019 - Supervisor, PhD student Bi Shaojie, College of Engineering, China Agricultural University during three-months study visit at SLU
2009 – present Supervision of five MSc students
I have published 28 peer-reviewed articles and one review in peer reviewed scientific journals and one book chapter. The publications have over 1000 citations (excluding self citations) yielding and H-index of 15.
Westerholm M, Liu, T, Schnurer A (2020) Comparative study of industrial-scale high-solid biogas production from food waste: Process operation and microbiology. Bioresource Technology, 304, 122981.
Bi S, Westerholm M, Qiao W, Xiong L, Mahdy A, Yin D, et al. (2020) Metabolic performance of anaerobic digestion of chicken manure under wet, high solid, and dry conditions. Bioresource Technology, 296, 122342.
Moestedt J, Westerholm M, Isaksson S, Schnürer A (2020) Inoculum source determines acetate and lactate production during anaerobic digestion of sewage sludge and food waste. Bioengineering 7, 3.
Westerholm, M, Castillo, MDP, Chan Andersson, A, Jahre Nilsen, P, Schnurer, A, 2019. Effects of thermal hydrolytic pre-treatment on biogas process efficiency and microbial community structure in industrial- and laboratory-scale digesters. Waste Management 95, 150-160. DOI: 10.1016/j.wasman.2019.06.004
Westerholm, M, Dolfing, J, Schnürer, A, 2019. Growth characteristics and thermodynamics of syntrophic acetate oxidizers. Environ Sci Technol 53, 5512-5520.
Bi, S, Westerholm, M, Qiao, W, Mahdy, A, Xiong, L, Yin, D, Fan, R, Dach, J, Dong, R, (2019) Enhanced methanogenic performance and metabolic pathway of high solid anaerobic digestion of chicken manure by Fe2+ and Ni2+ supplementation. Waste Management 94, 10-17.
Wandera, SM, Westerholm, M, Qiao, W, Yin, D, Jiang, M, Dong, R. (2018) The correlation of methanogenic communities' dynamics and process performance of anaerobic digestion of thermal hydrolyzed sludge at short hydraulic retention times. Bioresource Technology. 272, 180-187.
Westerholm M, Isaksson S, Karlsson Lindsjö O, Schnürer A. (2018) Microbial community adaptability to altered temperature conditions determines the potential for process optimisation in biogas production. Applied Energy 226, 838-848.
Schnürer A, Müller B, Westerholm M. (2018) Genus Syntrophaceticus. Bergey's Manual of Systematics of Archaea and Bacteria. In press.
Zhao J, Westerholm M, Qiao W, Yin D, Bi S, Jiang M, et al. (2018) Impact of temperature and substrate concentration on degradation rates of acetate, propionate and hydrogen and their links to microbial community structure. Bioresource Technology 256, 44-52.
Yin D, Westerholm M, Qiao W, Bi S, Wandera SM, Fan R, Jiang M, Dong R (2018) An explanation of the methanogenic pathway for methane production in anaerobic digestion of nitrogen-rich materials under mesophilic and thermophilic conditions. Bioresource Technology 264, 42-50.
Westerholm M, Müller B, Singh A, Karlsson Lindsjö O, Schnürer A. (2017) Detection of novel syntrophic acetate-oxidising bacteria from biogas processes by continuous acetate enrichment approaches. Microbial Biotechnology 11, 680-693.
Westerholm M, Moestedt J, Schnürer A (2016) Biogas production through syntrophic acetate oxidation and deliberate operating strategies for improved digester performance. Applied Energy 179, 124-135. (Review)
Westerholm M, Crauwels S, Houtmeyers S, Meerbergen K, Van Geel M, Lievens B, Appels L (2016) Microbial community dynamics linked to enhanced substrate availability and biogas production of electrokinetically pre-treated waste activated sludge. Bioresource Technology 218, 761-770.
Westerholm M, Crauwels S, Van Geel M, Dewil R, Lievens B, Appels L (2016) Microwave and ultrasound pre-treatments influence microbial community structure and digester performance in anaerobic digestion of waste activated sludge. Microbiology and Biotechnology, 100:5339-5352.
Müller B, Sun L, Westerholm M, Schnürer A (2016) Bacterial community composition and fhs profiles of low and high ammonia biogas digesters reveal novel syntrophic acetate-oxidising bacteria. Biotechnology for Biofuels, 9:1-18.
Westerholm M, Müller B, Isaksson S, Schnürer A (2015) Trace element and temperature effects on microbial communitites and links to biogas digester performance at high ammonia levels. Biotechnology for Biofuels, 8:1-19.
Moestedt J, Müller B, Westerholm M, Schnürer A (2015) Ammonia threshold for inhibition of anaerbic digestion of thin stillage and the importance of organic loading rate. Microbial Biotechnology, 9:180-194.
Kim Y, Westerholm M, Scherer P (2014) Dual investigation of methanogenic processes by quantitative PCR and quantitative microscopic fingerprinting (QMF). FEMS Microbiology Letters, 360:1-9.
Sun L, Müller B, Westerholm M, Schnürer A (2014) Syntrophic acetate oxidation in industrial CSTR biogas digesters. Journal of Biotechnology, 171:39-4
Westerholm M, Levén L, Schnürer A (2012) Bioaugmentation of syntrophic acetate-oxidising culture in biogas reactors exposed to increasing levels of ammonia. Applied and Environmental Microbiology, 78:7619-7625.
Westerholm M, Hansson M, Schnürer A (2012) Improved biogas production from whole stillage by co-digestion with cattle manure. Bioresource Technology, 114:314-319.
Westerholm M, Müller B, Arthurson V, Schnürer A (2011) Changes in the acetogenic population in a mesophilic anaerobic digester in response to increasing ammonia concentration. Microbes and Environments, 26:347-353.
Westerholm M, Dolfing J, Sherry A, Gray ND, Head IM, Schnürer A (2011) Quantification of syntrophic acetate-oxidizing microbial communities in biogas processes. Environmental Microbiology Reports, 3:500-505.
Westerholm M, Roos S, Schnürer A (2011) Tepidanaerobacter acetatoxydans sp. nov., an anaerobic, syntrophic acetate-oxidizing bacterium isolated from two ammonium-enriched mesophilic methanogenic processes. Systematic and Applied Microbiology, 34:260-266.
Westerholm M, Roos S & Schnürer A (2010) Syntrophaceticus schinkii gen. nov., sp. nov., an anaerobic, syntrophic acetate-oxidizing bacterium isolated from a mesophilic anaerobic filter. FEMS Microbiology Letters 309: 100-104.