Jennifer Byrne , 2025-05-21 11:00:00
Key takeaways:
- Fermented cabbage protected polarized intestinal epithelial cells against cytokine-induced damage, whereas raw cabbage or brine did not.
- Benefits were similar with purchased and laboratory-produced sauerkraut.
The metabolites in fermented cabbage protected polarized intestinal epithelial cells against damage by proinflammatory cytokines, according to a study published in Applied and Environmental Microbiology.
These beneficial effects were not observed with raw cabbage, findings showed.
The metabolites in fermented cabbage protected polarized intestinal epithelial cells against damage by proinflammatory cytokines. Image: Adobe Stock.
Maria L. Marco
“Our study affirms how fermentation dramatically changes the bioactive composition of our foods and beverages, and how these changes may impact our digestive tract,” Maria L. Marco, PhD, co-author and professor in the department of food science and technology at University of California Davis, told Healio. “Although more studies need to be done, a picture is forming that we find health benefits from fermented foods not observed from consuming the raw or cooked ingredients these foods are made from.”
Beneficial metabolites
Previous studies have highlighted the health benefits of fermented vegetables, but the mechanisms by which positive outcomes occur is unknown, according to study background.
To better understand how fermented cabbage might affect intestinal function, Marco and Lei Wei, PhD, a postdoctoral researcher at UC Davis, compared raw cabbage, store-bought and laboratory-scale fermented cabbage, and liquid brine from the fermentation process.
The researchers prepared the laboratory ferments in a brine solution with and without Lactiplantibacillus plantarum and assessed both preparations after 7 and 14 days of incubation.
Marco and Wei used a polarized Caco-2 cell model to test the products against proinflammatory cytokine damage.
Results showed that the fermented cabbage — but not the raw cabbage or liquid brine — had protective effects against cytokine-induced damage to the Caco-2 monolayer.
Metabolomic analyses using liquid and gas chromatography led to the identification of 481 metabolites. The metabolites in the fermented cabbage — which included D-phenyl-lactate and indole-3-lactate — were distinct from the raw cabbage and changed over time and with the addition of L. plantarum.
“Our results are similar to prior studies with regard to some of the metabolite changes and potential for fermented cabbage to be gut barrier protective,” Marco said. “However, our work was more comprehensive than [what has been] reported previously.”
‘Good for gut health’
The researchers also evaluated the metabolites individually and found that they provided only partial protection against cytokine damage. This suggests that these protective compounds are steadily enriched during the fermentation process and more beneficial as a mixture.
“We also found that the enrichment of the mostly beneficial compounds was consistent across sauerkraut ferments,” Marco said. “This finding is useful because it suggests that, so long as the fermented cabbage is made correctly, we don’t need to rely on a single commercial brand to get a benefit from eating that type of food.”
Marco noted that although these findings are promising, research in humans is needed to determine whether these effects extend to a real-world setting.
“A major limitation is that the study was performed in vitro,” Marco said. “It is necessary to perform human studies to understand the gut modulatory effects of sauerkraut compared to raw or cooked cabbage.”
She added, “Fermented foods like sauerkraut are enriched in metabolites known to be good for gut health. They can be recommended for inclusion in a healthy diet.”
For more information:
Maria L. Marco, PhD, can be reached at mmarco@ucdavis.edu.
