Diversity of the gut microbiota is crucial for human health. A new study provides the first evidence of the interconnection between the plant and the gut microbiome. The connection is established mainly by three bacterial orders (Enterobacterales, Burkholderiales, and Lactobacillales), which, interestingly, harbor members of both plant and human probiotics.
Overview of the bioinformatic workflow for the recovery of metagenome-assembled genomes (MAGs) from fruits and vegetables and the detection of their presence in the gut. Image credit: Wicaksono et al., doi: 10.1080/19490976.2023.2258565.
The composition and function of the human gut microbiota are closely linked to our health during our whole lifespan.
Gut microbiota assembly is a complex process involving microbial seeding and succession driven by ecological forces and subject to environmental conditions.
Microbiome assembly starts during birth, and babies acquire their first microbiota inoculum from their mother and other humans as well as the local environment.
The development of the gut microbiota during early life depends on breast-feeding and environmental exposures and is critical for immune system development and long-term health outcomes.
Related to this, a growing body of evidence has shown that changes in the composition and diversity of the gut microbiota are linked to metabolic disorders such as obesity and type 2 diabetes mellitus, and chronic diseases such as asthma and type 1 diabetes.
Hence, it is of utmost importance to understand the factors influencing the composition and diversity of the gut microbiota.
“The proof that microorganisms from fruits and vegetables can colonize the human gut has now been established for the first time,” said Dr. Wisnu Adi Wicaksono, a researcher with the Institute of Environmental Biotechnology at Graz University of Technology.
“This suggests that the consumption of fruit and vegetables, especially in infancy, has a positive influence on the development of the immune system in the first three or so years of life, as the intestinal microbiome develops during this time. But even after that, a good diversity of gut bacteria is beneficial for health and resilience.”
“It simply influences everything. Diversity influences the resilience of the whole organism; higher diversity conveys more resilience,” said Dr. Gabriele Berg, head of the Institute of Environmental Biotechnology at Graz University of Technology.
In the study, the authors used a combination of bioinformatics tools to reconstruct representative genomes of fruit- and vegetable-associated bacteria from 156 fruit and vegetable metagenomes.
The reconstructed genomes were used as a basis to investigate the prevalence of fruit- and vegetable-associated bacteria in 2,426 publicly available gut metagenomes.
The researchers found that the microbiomes of fresh fruits and vegetables and the human gut are represented by Enterobacterales, Burkholderiales, and Lactobacillales bacteria.
Exposure to these bacteria via fruit and vegetable consumption potentially has a beneficial impact on the functional diversity of gut microbiota particularly due to the presence of putative health-promoting genes for the production of vitamin and short-chain fatty acids.
In the human gut, they were consistently present, although at a low abundance, approx. 2.2%.
Host age, vegetable consumption frequency, and the diversity of plants consumed were drivers favoring a higher proportion.
“Fresh fruit and vegetables will always have the best microbiome; agriculture or processing companies already have a major influence here. And the storage and processing of food must also be critically reconsidered,” Dr. Berg said.
“Every fruit and vegetable has a unique microbiome. So maybe at some point a personalized diet can be put together based on that.”
The findings were published in the journal Gut Microbes.
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Wisnu Adi Wicaksono et al. 2023. The edible plant microbiome: evidence for the occurrence of fruit and vegetable bacteria in the human gut. Gut Microbes 15 (2); doi: 10.1080/19490976.2023.2258565
