The reddish color of Acer genus leaves is due to anthocyanin pigments. In previous paper, these anthocyanins from Acer were reported as cyanidin glycosides and delphinidin glycosides. Galloyl cyanidin glycosides are distributed as a common anthocyanins from red leaves of Acer, but these pharmacological activities have not been investigated [1]. In this study, phytochemical composition of anthocyanins of Acer palmatum cv. ‘Chishio’ was analyzed, and their antiproliferative and antioxidantative activities were evaluated.
Phytochemical profiles of anthocyanins extracted from the leaves with 1% TFA in methanol were analyzed by HPLC-MS, and 4 cyanidin glucosides (cyanidin glucoside, cyanidin rutinoside, galloyl cyanidin glucoside and galloyl cyanidin rutinoside) were found in the leaves. Antiproliferative activities of each anthocyanins were evaluated against T47D, LLC and C3H10T1/2. Antiproliferative activities of galloyl cyanidin glucoside and galloyl cyanidin rutinoside against these cells with IC50 values of 100.7 and 118.2 µM (T47D), 124.0 and 303.8 µM (LLC) and 158.4 and 326.9 µM (C3H10T1/2), respectively. Antioxidant activities of each anthocyanins were evaluated using in vitro free radical scavenging assay (DPPH method). The antioxidative activities of all compounds were comparable to ascorbic acid used as the positive control.
[1] Ji S-B, Saito N, Yokoi M, Shigihara A, Honda T. Phytochemistry 1992; 31: 655-657.