ArticleApplied and environmental microbiology2001
Degradation of quercetin and luteolin by Eubacterium ramulus.
Article in Applied and environmental microbiology, 2001. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 70 papers.
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Who cites it
70 citing papers in PubMed, 223 citations in OpenAlex.
- Trial
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- Aspalathin-Rich Rooibos Tea Extract Regulates Hepatic Lipid Metabolism and Gut Microbiota in High-Fat Diet Fed Mice.Nutrients · 2026Article
- Gut microbiome profiles in Chilean participants with colorectal adenomas: an exploratory 16S rRNA sequencing study.Scientific reports · 2026Article
- Anti-Cancer Effects of Quercetin: What Role Does the Gut Microbiota Play?Molecules (Basel, Switzerland) · 2026Review
- Functional remodeling of the gut microbiome and metabolome in primary idiopathic male infertility.BMC microbiology · 2026Article
- Identification of Novel Metabolic Signatures on Human Gut Microbiota: Ellagic Acid, Naringenin, and Phloroglucinol.International journal of molecular sciences · 2025Article
- Unlocking Polyphenol Efficacy: The Role of Gut Microbiota in Modulating Bioavailability and Health Effects.Nutrients · 2025Review
- Modulation of Antioxidant Capacity, Nutritional Composition, Probiotic Viability After Digestion and Sensory Attributes of Plant-Based Beverages Through Lactic Acid Fermentation.Foods (Basel, Switzerland) · 2025Article
- Biotransformation of quercetin by Bacillus subtilis and anticancer activity evaluation: in vitro and in Silico.AMB Express · 2025Article
- Flavonoid-converting capabilities of Clostridium butyricum.Applied microbiology and biotechnology · 2025Article
- Article
- Comparison of In Vitro Biotransformation of Olive Polyphenols Between Healthy Young and Elderly.Metabolites · 2025Article
- Polyphenol rewiring of the microbiome reduces methane emissions.The ISME journal · 2025Article
- Effects of Phenolic Acids Produced from Food-Derived Flavonoids and Amino Acids by the Gut Microbiota on Health and Disease.Molecules (Basel, Switzerland) · 2024Review
- Dietary Polyphenols and Gut Microbiota Cross-Talk: Molecular and Therapeutic Perspectives for Cardiometabolic Disease: A Narrative Review.International journal of molecular sciences · 2024Review
- Genomics and physiology ofMicrobial genomics · 2024Article
- Article
- Gut Microbiota and Inflammation Modulation in a Rat Model for Ulcerative Colitis after the Intraperitoneal Administration of Apigenin, Luteolin, and Xanthohumol.International journal of molecular sciences · 2024Article
10 more citing papers are in PubMed but not listed here.
Corrections and comments
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Authors and funding
4 authors at 2 institutions in 2 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
The degradation of the flavonol quercetin and the flavone luteolin by Eubacterium ramulus, a strict anaerobe of the human intestinal tract, was studied. Resting cells converted these flavonoids to 3,4-dihydroxyphenylacetic acid and 3-(3,4-dihydroxyphenyl)propionic acid, respectively. The conversion of quercetin was accompanied by the transient formation of two intermediates, one of which was identified as taxifolin based on its specific retention time and UV and mass spectra. The structure of the second intermediate, alphitonin, was additionally elucidated by (1)H and (13)C nuclear magnetic resonance analysis. In resting-cell experiments, taxifolin in turn was converted via alphitonin to 3,4-dihydroxyphenylacetic acid. Alphitonin, which was prepared by enzymatic conversion of taxifolin and subsequent purification, was also transformed to 3,4-dihydroxyphenylacetic acid. The coenzyme-independent isomerization of taxifolin to alphitonin was catalyzed by cell extract or a partially purified enzyme preparation of E. ramulus. The degradation of luteolin by resting cells of E. ramulus resulted in the formation of the intermediate eriodictyol, which was identified by high-performance liquid chromatography and mass spectrometry analysis. The observed intermediates of quercetin and luteolin conversion suggest that the degradation pathways in E. ramulus start with an analogous reduction step followed by different enzymatic reactions depending on the additional 3-hydroxyl group present in the flavonol structure.
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