Volkmar Passoth

I am running and coordinating yeast research within the feed- and food microbiology group, teaching mycology, general microbiology and microbial metabolism. Recently, I also took over the responsibility as a director of studies of the industry PhD- program LivsID (https://www.slu.se/utbildning/program-kurser/forskarutbildning/livsid/).

Oleaginous yeasts for biofuels and fish feed

I am together with Mats Sandgren coordinating the research program LipoDrive (https://www.slu.se/en/Collaborative-Centres-and-Projects/lipodrive/). In this project we investigate oleaginous yeasts, which can produce microbial lipids from lignocellulose hydrolysate (wheat straw, wood residues) and crude glycerol (a residue from biodiesel production). The lipids can be used for sustainable production of biodiesel, food and feed ingredients.

Microbial fermentation for improved animal feed and biopreservation

Fermentation can improve the nutritional characteristics of both grain- and lignocellulose- based feed material. It can even prevent spoilage by undisirable microorganisms. Yeasts grown on different substrates can also be used as protein- and lipid source in fish feed. We are analysing the microbial populations in a variety of feed fermentations, and specifically investigate the physiology of the biocontrol yeast Wickerhamomyces anomalus (previous names: Hansenula anomala, Pichia anomala). In our fermentations, we have seen a reduction of the antinutrient phytate, and an inhibition of moulds and Enterobacteriaceae. We have even seen that biopreservation of both cereal grain and wheat straw can increase ethanol production from this material.

Novel ethanol production yeasts

When investigating the microbial population in a Swedish ethanol plant we found that Brettanomyces bruxellensis (synonyme Dekkera bruxellensis) had outcompeted the originally inocculated production organism Saccharomyces cerevisiae. Nevertheless, production was obviously not negatively influenced, B. bruxellensis can thus be seen as production organism. This was in a way challenging the dogma about competitivness of S. cerevisiae in ethanol processes. We are investigating physiology and genome of this yeast, to understand its exceptional stress tolerance.

I was also working on the physiology and genetics of the xylose- fermenting yeast Scheffersomyces stipitis (previous name Pichia stipitis). This yeast has, apart from its exceptional ability to ferment xylose to ethanol, an interesting response to oxygen limitation. We even found that this yeast has some antifungal activity.

M.Sc. in biology at Greifswald University (Germany- and the oldest Swedish university during almost 200 years) 1992

PhD in microbiology at Aachen University 1998

Post-doc at Lund University (Group of Prof. Bärbel Hahn-Hägerdal, Marie-Curie Grant) 1998- 2000

Post-doc at Greifswald University (Molecular Biologist in the group "Molecular Cardiology") 2001-2002

Assistant Professor at SLU Uppsala 2002-2005

Associate Professor at SLU Uppsala since 2005

Blomqvist J, Pickova J, Tilami SK, Sampels S, Mikkelsen N, Brandenburg J, Sandgren M, Passoth V (2018). Oleaginous yeast as a component in fish feed. Sci Rep. in press
Brandenburg J, Poppele I, Blomqvist J, Puke M, Pickova J, Sandgren M, Rapoport A, Vedernikovs N, Passoth V (2018) Bioethanol and lipid production from the enzymatic hydrolysate of wheat straw after furfural extraction. Appl Microbiol Biotechnol 102, 6269-6277. https://doi.org/10.1007/s00253-018-9081-7
Huyben D, Boqvist S, Passoth V, Renström L, Bengtsson UA, Andréoletti O, Kiessling A, Lundh T, Vågsholm I (2018). Screening of intact yeasts and cell extracts to reduce Scrapie prions during biotransformation of food waste. Acta Vet Scandinavia 60: 9
Karlsson H, Ahlgren S, Sandgren M, Passoth V, Wallberg O, Hansson PA (2017). Greenhouse gas performance of biochemical biodiesel production from straw- soil organic carbon changes and time-dependent climate impact. Biotechnol Biofuels 10, 273
Huyben D, Nyman A, Vidakovic A, Passoth V, Moccia R, Kiessling A, Dicksved J, Lundh T (2017). Effects of dietary inclusion of the yeasts Saccharomyces cerevisiae and Wickerhamomyces anomalus on gut microbiota of rainbow trout. Aquaculture 473, 528-537. doi http://dx.doi.org/10.1016/j.aquaculture.2017.03.024
Katongole CB, Bakeeva A, Passoth V, Lindberg JE (2017). Effect of solid-state fermentation with Arxula adeninivorans or Hypocrea jecorina (anamorph Trichoderma reesei) on hygienic quality and in-vitrodigestibility of banana peels by mono-gastric animals. Livestock Science 199, 14-21
Karlsson H, Ahlgren S, Sandgren M, Passoth V, Wallberg O, Hansson PA (2016). A systems analysis of biodiesel production from wheat straw using oleaginous yeast: process design, mass and energy balances. Biotechnol Biofuels 9, 229
Brandenburg J, Blomqvist J, Pickova J, Bonturi N, Sandgren M, Passoth V. (2016). Lipid production from hemicellulose with Lipomyces starkeyi in a pH regulated fed batch cultivation. Yeast 33, 451-462. doi: 10.1002/yea.3160.