Quercetin — the cannabis flavonoid in depth
Quercetin is a flavonol with molecular formula C₁₅H₁₀O₇ and molar mass 302.24 g/mol. Outside cannabis, Quercetin is also found in onions, apples, berries, green tea, capers. Within the cannabis flower, flavonoids form the "third pillar" of phytochemistry alongside cannabinoids and terpenes. They are responsible for colour nuances of the leaves and flowers and are increasingly a focus of entourage-effect research.
flavonol · C₁₅H₁₀O₇ · yellow pigment — gives onion skins and cannabis leaves their colour
Chemistry
Chemically, Quercetin is a flavonol. As a flavonol it carries a 3-hydroxy group on the C-ring — this favours antioxidant capacity. Combustion (>240 °C) largely destroys the flavonoid fraction; vaporisation at 170–200 °C preserves a much larger share.
Occurrence
Flavonoids typically make up 0.3–2.5 % of a cannabis flower's dry weight. Quercetin is produced together with other phenols in the leaves and outer flower. yellow pigment — gives onion skins and cannabis leaves their colour — this partly explains colour differences between chemovars. Quercetin is quantified by HPLC-DAD or LC-MS. Swiss COAs rarely list flavonoids today, but the analytics are established and should become standard as regulation progresses.
Effect
Widely studied antioxidant; preclinically anti-inflammatory, antiviral and a potential CYP3A4/2C9 inhibitor (drug interactions). Evidence: Li Y et al. 2016 (review); EFSA opinions on flavonoids. Legal note: in Switzerland, cannabis with ≥ 1 % THC is a narcotic. Flavonoids themselves are unregulated. Effect descriptions are not therapeutic claims.
FAQ
What is Quercetin?
A flavonol with formula C₁₅H₁₀O₇, found in onions, apples, berries, green tea, capers.
Does the concentration vary between strains?
Yes — depending on chemovar, cultivation and harvest. Total flavonoid fraction is 0.3–2.5 % of dry weight.
What is the effect of Quercetin?
Widely studied antioxidant; preclinically anti-inflammatory, antiviral and a potential CYP3A4/2C9 inhibitor (drug interactions).
Is Quercetin legal?
Yes. As a flavonoid it is unregulated and is used in food and nutraceuticals.
Does combustion destroy Quercetin?
Largely yes. Above 240 °C the flavonoid fraction is destroyed. Vaporising at 170–200 °C preserves much more.