Pycnogenol (French Maritime Pine Bark)

Pycnogenol is a standardized extract from the bark of French Maritime Pine (Pinus pinaster), not consumed as a macronutrient source but valued for its dense concentration of bioactive polyphenolic compounds. Key constituents include: **Procyanidins** (oligomeric proanthocyanidins/OPCs, comprising 65–75% of the extract), which are polymers of catechin and epicatechin units (primarily dimers through heptamers); **Catechin** (~2–4% free form) and **Epicatechin** (~1–2%), both flavan-3-ol monomers with direct antioxidant activity; **Taxifolin** (dihydroquercetin, ~2–5%), a potent flavonoid with anti-inflammatory properties; **Phenolic acids** including caffeic acid (~1–3%), ferulic acid (~0.5–1.5%), and protocatechuic acid (~0.5–1%); and **Gallic acid** (~trace–1%). The extract contains negligible macronutrients (no significant protein, fat, carbohydrate, or fiber) at typical supplemental doses of 50–300 mg/day. No appreciable vitamins or minerals are present in meaningful amounts. **Bioavailability notes:** The smaller molecular weight compounds (catechin, taxifolin, phenolic acids) are readily absorbed in the small intestine with moderate oral bioavailability. Larger procyanidin oligomers (trimers and above) have limited direct absorption but undergo extensive colonic microbial metabolism, yielding bioactive metabolites such as δ-(3,4-dihydroxyphenyl)-γ-valerolactone (M1) and δ-(3-methoxy-4-hydroxyphenyl)-γ-valerolactone (M2), which are detectable in plasma within 2–6 hours and contribute significantly to systemic bioactivity. Peak plasma concentrations of metabolites reach approximately 50–150 ng/mL after a standard 200 mg dose. The antioxidant capacity (ORAC value) of the extract is exceptionally high at approximately 3,500–4,000 µmol TE/g, roughly 20× that of vitamin C on a weight basis.