Dr. Heike Sträuber

CV / Scientific Career

Research interests

My work focuses on gaining a deeper understanding of microbial relationships and activities in the anaerobic fermentation process. This aims at a higher efficiency of processes for the production of carboxylate platform chemicals (e.g. short and medium-chain fatty acids as well as branched and unbranched VFA) or methane from biomass. The effects of secondary plant metabolites and additives like trace elements are evaluated. Microbial chain elongation with lactic acid and ethanol as well as the combination with syngas fermentation is of special interest. Besides CSTRs, mainly solid-state fermentation systems (leach-bed reactors) are used for the anaerobic fermentation of plant biomass (dedicated crops) or waste. Metabolic fluxes between microorganisms and behaviour of key players are being analyzed. Process parameters are correlated with microbiological data from molecularbiological analyses (mainly T-RFLP and next generation sequencing) using multivariate statistical tools.

In the last years, the CAPRAFERM^® process was developed. This is an anaerobic fermentation process for production of caproic and caprylic acid from complex biomass. In different project, the CAPRAFERM^® process is being further developed in the sense of a biorefinery in cooperation with DBFZ (German Biomass Research Centre), other academic partners and large industries. The partners develop the downstream processing and product refining and test the chemicals in specific end products. Furthermore, we investigate how existing biogas plants can be refitted to biorefineries. This will give biogas plant owners alternative sources of income.

Selected publications

Review:

Chowdhury R, Ghosh S, Manna D, Das S, Kleinsteuber S, Sträuber H, Hassan MK, Kuittinen S, Pappinen A (2019) Hybridization of sugar-carboxylate-syngas platforms for the production of bio-alcohols from lignocellulosic biomass (LCB) - a state-of-the-art review and recommendations. Energ Conv Manag, 200:112111, doi: 10.1016/j.enconman.2019.112111

Baleeiro FCF, Kleinsteuber S, Neumann A, Sträuber H (2019) Syngas-aided anaerobic fermentation for medium-chain carboxylate and alcohol production: The case for microbial communities. Appl Microbiol Biotechnol, doi: 10.1007/s00253-019-10086-9

Sträuber, H., Müller, S. (2010): Viability states of bacteria – specific mechanisms of selected probes. Cytometry Part A 77A:623-634.

Book chapters:

Liebetrau J, Weinrich S, Sträuber H, Kretzschmar J (2019): Anaerobic fermentation of organic material: Biological processes and their control parameters. In: Kaltschmidt M (Hrsg.), Energy from organic materials (biomass). Encyclopedia of Sustainability Science and Technology Series. doi:10.1007/978-1-4939-2493-6_962-1, Springer, New York, S. 779-807

Liebetrau J, Sträuber H, Kretzschmar J, Denysenko V, Nelles M (2017): Anaerobic Digestion. In: Wagemann, K, Tippkötter, N (Hrsg.), Biorefineries. Advances in Biochemical Engineering/Biotechnology, vol 166, doi:10.1007/10_2016_67, Springer, Cham, S. 281-299

Dieckmann C, Edelmann W, Kaltschmitt M, Liebetrau J, Oldenburg S, Ritzkowski M, Scholwin F, Sträuber H, Weinreich S (2016): Biogaserzeugung und –nutzung. In: M. Kaltschmitt, H. Hartmann, H. Hofbauer (Hrsg.), Energie aus Biomasse: Grundlagen, Techniken und Verfahren. doi:10.1007/978-3-662-47438-9_19, Springer-Verlag Berlin Heidelberg, S. 1609-1635

Research articles:

Liu B, Kleinsteuber S, Centler F, Harms H, Sträuber H (2020) Competition between butyrate fermenters and chain-elongating bacteria limits the efficiency of medium-chain carboxylate production. Front Microbiol, 11:336, doi:10.3389/fmicb.2020.00336

Kasmaei KM, Schlosser D, Sträuber H, Kleinsteuber S (2020) Does glucose affect the de-esterification of methyl ferulate by Lactobacillus buchneri? MicrobiologyOpen 00:e971, doi: 10.1002/mbo3.971

Lambrecht J, Cichocki N, Schattenberg F, Kleinsteuber S, Harms H, Müller S, Sträuber H (2019) Key subcommunity dynamics of medium-chain carboxylate production. Microb Cell Factories, 18:92, doi:10.1186/s12934-019-1143-8

Janke L, Weinrich S, Leite AF, Sträuber H, Nikolausz M, Nelles M, Stinner W (2019) Pre-treatment of filter cake for anaerobic digestion in sugarcane biorefineries: Assessment of batch versus semi-continuous experiments. Renew Energ, 143:1416-1426, doi:10.1016/j.renene.2019.05.029

Bonk F, Popp D, Weinrich S, Sträuber H, Becker D, Kleinsteuber S, Harms H, Centler F (2019) Determination of microbial maintenance in aceto- and methanogenesis by experimental and modelling techniques. Front Microbiol, 10:166, doi:10.3389/fmicb.2019.00166

Bonk F, Popp D, Weinrich S, Sträuber H, Kleinsteuber S, Harms H, Centler F (2018) Ammonia inhibition of anaerobic volatile fatty acid degrading microbial communities. Front Microbiol, 9:2921, doi:10.3389/fmicb.2018.02921

Bonk F, Popp D, Weinrich S, Sträuber H, Kleinsteuber S, Harms H, Centler F (2018) Intermittent fasting for microbes: how discontinuous feeding increases functional stability in anaerobic digestion. Biotechnol Biofuels 11:274, doi:10.1186/s13068-018-1279-5

Jahnke L, Weinrich S, Leite AF, Sträuber H, Radetski CM, Nikolausz M, Nelles M, Stinner W (2018) Year-round biogas production in sugarcane biorefineries: Process stability, optimization and performance of a two-stage reactor system. Energy Convers Manag, 168:188-199, doi: 10.1016/j.enconman.2018.04.101

Sträuber H, Bühligen F, Kleinsteuber S, Dittrich-Zechendorf M (2018) Carboxylic acids production from ensiled crops in anaerobic solid-state fermentation – trace elements as pH controlling agents support microbial chain elongation with lactic acid. Eng Life Sci, 18(7):447-458, doi: 10.1002/elsc.201700186.

Urban C, Xu J, Sträuber H, dos Santos Dantas TR, Mühlenberg J, Härtig C, Angenent LT, Harnisch F (2017) Production of drop-in fuel from biomass at high selectivity by combined microbial and electrochemical conversion. Energ Environ Sci 10:2231-2244, doi: 10.1039/C7EE01303E.

Popp D, Plugge C, Kleinsteuber S, Harms H, Sträuber H (2017) Inhibitory effect of coumarin on syntrophic fatty acid oxidizing and methanogenic cultures and biogas reactor microbiomes. Appl Environ Microbiol 83:e00438-17, doi: 10.1128/AEM.00438-17.

Popp D, von Gillhaussen P, Weidlich EWA, Sträuber H, Harms H, Temperton VM (2017) Methane yield of biomass from extensive grassland is affected by compositional changes induced by order of arrival. GCB Bioenergy 9(10):1555-1562, doi: 10.1111/gcbb.12441.

Wintsche B, Glaser K, Sträuber H, Centler F, Liebetrau J, Harms H, Kleinsteuber S (2016): Trace elements induce predominance among methanogenic activity in anaerobic digestion. Front Microbiol. 7:2034, doi: 10.3389/fmicb.2016.02034.

Popp D, Harms H, Sträuber H (2016): The alkaloid gramine in the anaerobic digestion process – inhibition and adaptation of the methanogenesis. Applied Microbiology and Biotechnology 100(16):7311-7322.

Hofmann J, Peltri G, Sträuber H, Müller L, Schumacher B, Müller U, Liebetrau J (2016): Statistical interpretation of semi-continuous anaerobic digestion experiments on the laboratory scale. Chemical Engineering & Technology 39(4):643-651.

Sträuber H, Lucas R, Kleinsteuber S (2016): Metabolic and Microbial Community Dynamics during the Anaerobic Digestion of Maize Silage in a Two-Phase Process. Applied Microbiology and Biotechnology 100(1):479-491.

Janke L, Leite A, Batista K, Weinrich S, Sträuber H, Nikolausz M, Nelles M, Stinner W (2016): Optimization of hydrolysis and volatile fatty acids production from sugarcane filter cake: Effects of urea supplementation and sodium hydroxide pretreatment. Bioresource Technology 199:235-244.

Popp D, Schrader S, Kleinsteuber S, Harms H, Sträuber H (2015): Biogas production from coumarin-rich plants – impact of coumarin on process parameters and microbial community. FEMS Microbiology Ecology 91(9):fiv103.

Sträuber H, Bühligen F, Kleinsteuber S, Nikolausz M, Porsch K (2015): Improved Anaerobic Fermentation of Wheat Straw by Alkaline Pre-Treatment and Addition of Alkali-Tolerant Microorganisms. Bioengineering 2(2):66-93.

Nikolausz M, Walter RFH, Sträuber H, Liebetrau J, Schmidt T, Kleinsteuber S, Bratfisch F, Günther U, Richnow HH (2013): Evaluation of Stable Isotope Fingerprinting Techniques for the Assessment of the Predominant Methanogenic Pathways in Anaerobic Digesters. Applied Microbiology and Biotechnology 97(5):2251-2262.

Sträuber H, Schröder M, Kleinsteuber S (2012): Metabolic and Microbial Community Dynamics during the Hydrolytic and Acidogenic Fermentation in a Leach-Bed Process. Energy, Sustainability and Society 2(1):13-23.

Sträuber H, Hübschmann T, Jehmlich N, Schmidt F, von Bergen M, Harms H, Müller S (2010): NBDT (3-(N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino)-3-toluene) - A Novel Fluorescent Dye for Studying Mechanisms of Toluene Uptake into Vital Bacteria. Cytometry Part A 77A(2):113-120.

Heine F, Stahl F, Sträuber H, Wiacek C, Benndorf D, Repenning C, Schmidt F, Schepe, T, von Bergen M, Harms H, Müller S (2009): Prediction of Flocculation Ability of Brewing Yeast Inoculates by Flow Cytometry, Proteome Analysis, and mRNA Profiling. Cytometry Part A 75A(2):140-147.

Sträuber H, Müller RH, Babel W (2003): Evidence of Cytochrome P450-catalyzed etherolytic cleavage of phenoxybutyrate herbicides in Rhodococcus erythropolis K2-3. Biodegradation 14:41-50.

Müller S, Sträuber H, Lösche A, Babel W (2002): Population analysis of a binary bacterial culture by multi-parametric flow cytometry. Journal of Biotechnology 97:163-176.

Müller S, Lösche A, Mertingk H, Beisker W, Babel W (2000): Flow cytometric monitoring of Rhodococcus erythropolis and Ochrobactrum anthropi in a mixed culture. Acta Biotechnologica 20:219-233.

Mertingk H, Müller RH, Babel W (1998): Etherolytic cleavage of 4-(2,4-dichlorophenoxy)butyric acid and 4-(4-chloro-2-methylphenoxy)butyric acid by species of Rhodococcus and Aureobacterium isolated from an alkaline environment. Journal of Basic Microbiology 38:257-267.