Julia Haarhuis

Postgraduate Student

Health benefits of dietary polyphenols

I am a PhD student on the Wellcome Trust-funded EDESIA programme in the research group of Dr Paul Kroon. My work focuses on the metabolism of L-carnitine to microbially-produced trimethylamine (TMA). TMA is converted in the liver to the atherogenic trimethylamine N-oxide (TMAO), so I study the potentially inhibitory effect that dietary polyphenols from pomegranate may have on L-carnitine metabolism. This project is a cross-institutional collaboration with Dr Christopher Quince at the Earlham Institute, with whom we develop assays to study the gut microbiota involved in the TMA production from L-carnitine.

Prior to this PhD position at QIB, I have obtained both my BSc and MSc in Nutrition and Health at Wageningen University in the Netherlands. During this time, I completed 6 months of taught modules at the University of California, Los Angeles (UCLA) and spent 10 months as a Visiting Graduate Researcher at their Neuroscience department. I also did a 6-month research internship in the Microbiomics, Nutrition & Health group at NIZO Food Research in the Netherlands.

Key Publications

Haarhuis, J. E., Kardinaal, A., & Kortman, G. A. M. (2022). Probiotics, prebiotics and postbiotics for better sleep quality: a narrative review. Beneficial Microbes, 13(3), 169-182. DOI: 10.3920/bm2021.0122