Fisetin purity is confirmed by HPLC with specific quantification of fisetin aglycone — not total flavonoid content. Batch testing includes absence of fustin (the primary related compound), heavy metals, and microbial safety to GMP pharmacopoeia standards.
COA reports specific fisetin aglycone content. Fustin (the 3-deoxyfisetin precursor in Rhus wood) is identified and reported separately as an impurity. Minimum 98% fisetin confirmed on every batch.
Fisetin's orange-yellow chromophore is photosensitive. Opaque, nitrogen-flushed aluminium packaging preserves both colour and bioactivity throughout storage and international transit.
Botanical-source fisetin is tested for lead, mercury, arsenic, cadmium, ochratoxin A, and aflatoxins where applicable. Synthetic/semi-synthetic grades tested for residual solvents (ICH Q3C).
COA, MSDS, Certificate of Origin, and Phytosanitary Certificate with every shipment. Halal and Kosher certificates on request. Full digital documentation before dispatch.
No natural compound has generated as much longevity science interest per dollar of consumer awareness as fisetin. Found in strawberries at microgram-per-gram levels, the idea that you would need to eat 37 strawberries per day to get a 100mg supplement dose helps consumers understand why concentrated bulk fisetin exists. But the science behind the 2018 Mayo Clinic results — and the translation from mouse studies to human protocols — requires careful interpretation for formulators building scientifically credible products.
Yousefzadeh et al., EBioMedicine 2018: fisetin was the most potent of 10 flavonoids tested as senolytics in aged mice. Administered late-in-life (month 22 of ~30 month lifespan), fisetin extended both median and maximum remaining lifespan. This is the most compelling longevity dataset for any natural flavonoid. Note: This was a mouse study — human trials on lifespan are impossible to conduct, but tissue senescence marker studies in humans are ongoing at Mayo.
Natural fisetin content — Strawberry 160 µg/g; Apple 26 µg/g; Persimmon 11 µg/g; Onion 5 µg/g; Cucumber 0.1 µg/g. At 160 µg/g, a 100mg supplement dose requires approximately 625g of strawberries. This communication point resonates with consumers and validates the need for concentrated supplemental fisetin. Commercial extraction comes from Rhus succedanea wax tree fruits or semi-synthesis.
The Mayo Clinic mouse study used continuous supplementation at ~100mg/kg. Translating this to human protocols, researchers are investigating both daily dosing (100–200mg) and intermittent high-dose "pulse" approaches (500–1,000mg for 2 consecutive days monthly). The pulse approach mimics the dasatinib/quercetin protocol logic. For consumer supplements, daily 100–200mg is most practical; clinical longevity products increasingly use the pulse protocol. No established human therapeutic dose yet — clinical trials ongoing.
Fisetin (most potent senolytic) + Quercetin (broadest anti-inflammatory + antiviral) is the most scientifically supported natural senolytic combination. Their mechanisms are complementary: fisetin inhibits PI3K/AKT survival pathways more potently; quercetin adds mast cell stabilisation and COMT inhibition. From a formulation standpoint, both flavonoids have poor oral bioavailability that can be addressed through phytosome complexation or fat co-ingestion.