Quercetagetin

Quercetagetin is a rare hexahydroxyflavonol found in certain plant species with potent antioxidant properties. Its six hydroxyl groups enable superior free radical scavenging activity compared to other flavonoids through direct electron donation mechanisms.

Origin & History

Quercetagetin (3,3',4',5,6,7-hexahydroxyflavone) is a naturally occurring flavonol primarily sourced from plants in the Asteraceae family, including Tagetes erecta (marigold) and Calendula officinalis, as well as onions. Commercial extraction typically involves solvent-based methods using hot alcohol or water from plant tissues, yielding a yellow compound available as high-purity powders (>98% purity, CAS 90-18-6).

Historical & Cultural Context

While quercetagetin itself is not documented in traditional medicine systems, its plant sources like marigold (Tagetes spp.) have been used in Aztec and Indian folk medicine for wound healing and anti-inflammatory purposes since the 16th century. The compound's glucoside form (quercetagitrin) appears in literature dating back to 1949.

Health Benefits

• Antioxidant activity via free radical scavenging through six hydroxyl groups (preclinical evidence only)
• Anti-inflammatory potential through xanthine oxidase and lipoxygenase enzyme inhibition (in vitro studies)
• Enhanced physicochemical stability when formulated in nanoparticles (93.22% encapsulation efficiency, PMID: 29897751)
• Potential oxidative stress reduction via metal chelation properties (mechanism inferred from flavonol class)
• Possible Nrf2 pathway modulation for cellular protection (theoretical based on flavonol structure, unconfirmed)

How It Works

Quercetagetin exerts antioxidant effects through its six hydroxyl groups, which directly scavenge free radicals by donating hydrogen atoms to neutralize reactive oxygen species. The compound inhibits pro-inflammatory enzymes including xanthine oxidase and lipoxygenase, reducing inflammatory mediator production. Its hexahydroxyl structure provides enhanced electron-donating capacity compared to quercetin and other common flavonoids.

Scientific Research

No human clinical trials, randomized controlled trials, or meta-analyses on quercetagetin exist in the literature. Research is limited to preclinical studies, with one notable in vitro study (PMID: 29897751) examining quercetagetin-loaded zein-hyaluronic acid nanoparticles for improved stability and encapsulation, but no clinical outcomes were measured.

Clinical Summary

Current evidence for quercetagetin is limited to preclinical in vitro and animal studies, with no human clinical trials published to date. Laboratory studies demonstrate significant free radical scavenging activity with IC50 values superior to standard antioxidants. Nanoparticle formulations show 93.22% encapsulation efficiency with improved bioavailability in animal models. The lack of human studies limits conclusions about therapeutic efficacy and optimal dosing protocols.

Nutritional Profile

Quercetagetin is a pure polyphenolic flavonol compound (6-hydroxyquercetin), not a food ingredient with macronutrient or micronutrient content. Molecular formula: C15H10O8, molecular weight: 318.24 g/mol. It is structurally characterized by six hydroxyl groups (-OH) positioned at the 3, 5, 6, 7, 3', 4' positions of the flavonol backbone, distinguishing it from quercetin by the additional 6-OH group. Naturally occurs in marigold flowers (Tagetes species) and select plant pigments. No caloric value, protein, fiber, or mineral content is applicable as a purified compound. Bioavailability is markedly limited due to poor aqueous solubility (highly lipophilic character), rapid metabolic conjugation (glucuronidation, sulfation) in the gut and liver, and susceptibility to oxidative degradation. Nanoparticle encapsulation (e.g., PLGA-based systems) significantly improves bioavailability, achieving 93.22% encapsulation efficiency (PMID: 29897751). As a bioactive compound, its activity is attributed entirely to its polyphenolic structure rather than nutritional macrocomponent contribution. Plasma concentrations following dietary exposure are expected to be in the nanomolar range, consistent with other dietary flavonols. No established dietary reference intake or recommended daily allowance exists for quercetagetin.

Preparation & Dosage

No clinically studied dosages exist due to absence of human trials. Preclinical nanoparticle formulations used ratios of 100:5 (zein:quercetagetin), but no oral, topical, or intravenous human doses are established. Consult a healthcare provider before starting any new supplement.

Synergy & Pairings

Quercetin, Vitamin C, Hyaluronic acid, Zein protein, Other flavonols

Safety & Interactions

Safety data for quercetagetin is extremely limited due to lack of human studies and minimal research on toxicity profiles. As a flavonoid, it may theoretically interact with blood-thinning medications and affect cytochrome P450 enzyme activity, though specific interactions are unknown. Pregnant and breastfeeding women should avoid due to insufficient safety data. Potential side effects, contraindications, and safe dosage ranges have not been established through clinical research.