Orally administered delphinidin 3-rutinoside and cyanidin 3-rutinoside are directly absorbed in rats and humans and appear in the blood as the intact forms.J Agric Food Chem. 2001 Mar; 49(3):1546-51.JA
Four components of black currant anthocyanins (BCA), delphinidin 3-O-beta-rutinoside (D3R), cyanidin 3-O-beta-rutinoside (C3R), delphinidin 3-O-beta-glucoside (D3G), and cyanidin 3-O-beta-glucoside (C3G), were found to be directly absorbed and distributed to the blood and excreted into urine as the glycosylated forms. In a rat study, following oral administration of purified D3R, C3R, and C3G (800 micromol/kg of body weight), the anthocyanins were detected in the plasma and the C(max) values were 580 +/- 410, 850 +/- 120, and 840 +/- 190 nmol/L, respectively, 0.5-2.0 h after administration. In a human study, when a mixture of BCA [6.24 micromol (3.58 mg) consisting of 2.75 micromol (1.68 mg) of D3R, 2.08 micromol (1.24 mg) of C3R, 1.04 micromol (0.488 mg) of D3G, and 0.37 micromol (0.165 mg) of C3G/kg of body weight)] was orally ingested by eight volunteers, D3R, C3R, D3G, and C3G were detected in the plasma and urine. The plasma C(max) values were 73.4 +/- 35.0, 46.3 +/- 22.5, 22.7 +/- 12.4, and 5.0 +/- 3.7 nmol/L, respectively, 1.25-1.75 h after intake, and the cumulative excretion of the four compounds in urine in the period 0-8 h after intake was 0.11 +/- 0.05% of the dose ingested. These results indicate that 3-O-beta-rutinosyl anthocyanins were directly absorbed and distributed to the blood.