“…In one experiment conducted in healthy human volunteers, the maximum concentration of GA in plasma was 1.83±0.16 μmol/L after intake of 50 mg GA (12). In another experiment, after oral administration of 50, 100, and 150 mg/kg grape seed extract containing 91 mg GA/g of extract in male Sprague-Dawley rats, the C max of GA was 309.8 ±102.6, 239.6±39.2, and 323.4±76.9 ng/mL (13). In the present study, the C max of GA was 2.5±0.18 μg/mL after 150 mg/kg oral dose of pure GA, which is quite comparable to previous works.…”