Child eating spruce

Eat wood to promote health and combat disease

Should we literally start eating our Christmas trees? A new study published in Nature Communications suggest just that.

The study has found that bacteria in the human gut can turn dominant hemicellulose components in spruce and other softwood trees in to a potent anti-inflammatory compound, which protects from inflammatory disorders and colorectal cancer.

The human gut ecological niche is characterised by a nutritional hierarchy with only a few specialised members on the top of the fiber food chain. These members are able to ferment complex dietary fibers to health-promoting bioactive molecules, e.g. butyrate.

These health-promoting bacterial groups from the human gut microbiota have recently come more and more into focus, and the development of tailor-made dietary supplements to selectively boost this bacterial group is of great potential as a non-invasive strategy to combat disease and to promote health. It has the potential to be used in both food and feed, thereby promoting the health of humans and animals.

In the study published in the prestigious journal Nature Communications researchers from DTU, the Norwegian University of Life Sciences and the University of Michigan investigated the fiber utilisation capabilities of Roseburia intestinalis, an abundant and prevalent model butyrate producing bacterium from the human gut.  The study is related to a study from last year, published in Nature Microbiology, where the researchers were the first to the mechanism by which Roseburia intestinalis digests xylan that represents one of the most abundant fibers in human diet and the specific details that render this beneficial commensal of the human gut microbiota competitive on this type of fiber.

The current study revealed that the bacterium has evolved a complex protein apparatus that enables harvesting energy from complex β-mannans from diet, e.g. coffee, coconuts, but more surprisingly from softwood, e.g. spruce which we use for Christmas trees.

The action of this bacterial group converts the hemicellulose plant cell wall structural components β-mannan and glucuronoxylan to butyrate that communicates several beneficial health benefit to the human host.

“This discovery and the detailed knowledge on the precise preference of this bacterium to highly abundant components from woody biomass that we show in this study, and in a related study published in Nature Microbiology last year, offers exciting perspectives to add value to an abundant biomass resource by converting it to a prebiotic, which boosts butyrate producing members of the gut microbiota that confer important health benefits.” says Professor MSO Maher Abou Hachem from DTU Bioengineering, who is the PI on the DTU part of this study.

The next step is to conduct tests in animals and humans in order to develop a prebiotic dietary supplement based on soft wood fibers.

Read the article The human gut Firmicute Roseburia intestinalis is a primary degrader of dietary β-mannans in Nature Communications.

Related articles:

Nature Microbiology: Differential bacterial capture and transport preferences facilitate co-growth on dietary xylan in the human gut
DTU Bioengineering: Specialdesignet kosttilskud til bestemte tarmbakterier