Named Bioactive Compounds · Compound
Rhamnetin (Flavonoid)
Moderate Evidenceflavonoid6 PubMed Studies
Hermetica Superfood Encyclopedia
Rhamnetin is a methylated flavonol compound that exhibits anti-inflammatory activity by inhibiting sPLA₂ enzymes and demonstrates antioxidant properties through free radical scavenging mechanisms. This flavonoid shows potential for reducing cellular toxicity with lower creatine kinase levels compared to other related flavonoids.
Rhamnetin is an O-methylated flavonoid (C₁₆H₁₂O₇) derived from quercetin through methylation at position 7, also known as 7-methoxyquercetin. It can be isolated from cloves and is commonly found in various fruits and vegetables. The compound has a molecular weight of 316.26 g/mol and is currently classified as an experimental compound in drug databases.
The available research on rhamnetin consists primarily of in vitro and mechanistic studies, with no published human clinical trials, RCTs, or meta-analyses found in the current search results. A peer-reviewed pharmacology and toxicity review exists in the literature, but specific trial data and PMIDs for human studies are not available. The compound remains classified as experimental, indicating lack of approved clinical use.
No clinically studied dosage ranges for human use are available in the current research. The compound is classified as experimental in drug databases and has not been approved for clinical use with established dosing protocols. Consult a healthcare provider before starting any new supplement.
Rhamnetin (7-O-methylquercetin; C₁₆H₁₂O₇; MW 316.26 g/mol) is a naturally occurring methylated flavonol, not a nutritional macronutrient source. It is a bioactive polyphenolic compound found in trace quantities in select plant sources. Key profile details: • Classification: 3,3',4',5-tetrahydroxy-7-methoxyflavone, a mono-methylated derivative of quercetin at the 7-OH position. • Natural occurrence: Found in small concentrations (typically µg/g range) in Rhamnus species (buckthorn), clove (Syzygium aromaticum), and some other medicinal plants; also present as a minor metabolite of quercetin in human metabolism via catechol-O-methyltransferase (COMT) activity. • Typical plant concentrations: Approximately 0.01–0.5 mg/g dry weight depending on plant source and extraction method; not consumed in nutritionally significant quantities through diet alone. • Bioactive compound class: Flavonol (subclass of flavonoids); contains a catechol (3',4'-dihydroxy) B-ring, a 3-hydroxyl group on the C-ring, and a 5-hydroxyl group on the A-ring, with the 7-position methoxy group distinguishing it from quercetin. • No significant macronutrient (protein, fat, carbohydrate, fiber) contribution at physiologically relevant doses. • No notable vitamin or mineral content intrinsic to the compound itself. • Key functional groups contributing to bioactivity: Multiple hydroxyl groups (antioxidant/chelation capacity), carbonyl at C-4 (hydrogen bonding), methoxy group at C-7 (increases lipophilicity, log P ~1.8–2.2 compared to quercetin's ~1.5). • Bioavailability notes: The 7-O-methylation increases hydrophobicity relative to quercetin, which theoretically enhances passive membrane permeability and intestinal absorption. However, oral bioavailability in humans remains poorly characterized. Like other flavonols, rhamnetin is subject to extensive Phase II metabolism (glucuronidation, sulfation) in the gut wall and liver, likely resulting in low systemic concentrations of the free aglycone (estimated low nanomolar plasma levels). The methoxy group may partially protect against rapid conjugation at the 7-position, potentially improving metabolic stability compared to quercetin. Protein binding is expected to be high (>90%). No established Recommended Daily Intake or tolerable upper limit exists for rhamnetin.
Rhamnetin exerts anti-inflammatory effects by inhibiting secretory phospholipase A₂ (sPLA₂) enzymes, which reduces the production of inflammatory mediators like prostaglandins and leukotrienes. The compound demonstrates antioxidant activity through its ability to scavenge free radicals and neutralize reactive oxygen species. Additionally, rhamnetin appears to protect cellular membranes and reduce cytotoxicity markers, including creatine kinase levels.
Current evidence for rhamnetin is limited to in vitro and mechanistic studies, with no human clinical trials available. Laboratory studies have demonstrated its sPLA₂ inhibitory activity and free radical scavenging capacity in cellular models. Research shows reduced creatine kinase levels compared to other flavonoids, suggesting better cellular protection profiles. However, the lack of human studies limits the translation of these mechanistic findings to real-world health benefits.
No specific safety data exists for rhamnetin supplementation in humans due to the absence of clinical trials. As a flavonoid compound, it may potentially interact with medications metabolized by cytochrome P450 enzymes, though specific interactions have not been documented. Pregnant and breastfeeding women should avoid rhamnetin supplements due to insufficient safety data. Individuals taking anticoagulant medications should exercise caution, as flavonoids may theoretically enhance bleeding risk.
