British Journal of Nutrition

Research Article

Cyanidin-3-O-β-glucopyranoside, a natural free-radical scavenger against aflatoxin B1- and ochratoxin A-induced cell damage in a human hepatoma cell line (Hep G2) and a human colonic adenocarcinoma cell line (CaCo-2)

M. C. Guerraa1 c1, F. Galvanoa2, L. Bonsia3, E. Speronia1, S. Costaa1, C. Renzullia1 and R. Cervellatia4

a1 Department of Pharmacology, University of Bologna, Via Irnerio 48, 40 126 Bologna, Italy

a2 Department of Agro-forestry, Environmental Science and Technology, University of Reggio Calabria, Piazza San Francesco 7, Reggio Calabria, Italy

a3 Institute of Histology and General Embryology, University of Bologna, Via Belmeloro 8, Bologna, Italy

a4 Department of Chemistry ‘G. Ciamician', University of Bologna, Via Selmi 2, Bologna, Italy


Recent findings have suggested that oxidative damage might contribute to the cytotoxicity and carcinogenicity of aflatoxin B1 (AFB1). Induction of oxidative stress also plays an important role in the toxicity of another mycotoxin, ochratoxin A (OTA). In the present study, the protective effect of cyanidin-3-O-β-glucopyranoside (C-3-G; an anthocyanin contained in oranges, blackberries, strawberries and cranberries) against AFB1- and OTA-induced cytotoxicity was investigated in a human hepatoma-derived cell line (Hep G2) and a human colonic adenocarcinoma cell line (CaCo-2). The ability of C-3-G to reduce the production of reactive oxygen species (ROS), the inhibition of protein and DNA synthesis and the apoptosis caused by the two mycotoxins was also investigated in both cell lines. Our experiments proved the significant cytoprotective effect of C-3-G in vitro against OTA- and AFB1-induced cell damage. In particular, 24 h of pretreatment with 50 μm-C-3-G inhibited the cytotoxicity of 10 μm-AFB1 (by 35 %) and of 10 μm-OTA (by 25 %) in Hep G2 cells (P<0·001) and of 10 μm-AFB1 (by 10 %, P<0·01) and of 10 μm-OTA (by 14 %, P<0·05) in CaCo-2 cells. Moreover, 50 μm-C-3-G attenuated ROS production induced by the two toxins in both cell lines (P<0·05). Inhibition of DNA and protein synthesis induced by the mycotoxins was counteracted by pretreatment with the antioxidant at 50 μm. Similarly, apoptotic cell death was prevented as demonstrated by a reduction of DNA fragmentation and inhibition of caspase-3 activation. The in vitro free-radical scavenging capacity of the anthocyanin was tested with the Briggs–Rauscher oscillating reaction. This system works at pH approximately 2. The results showed good scavenging power, in accordance with the observed inhibition of ROS production.

(Received June 22 2004)

(Revised December 20 2004)

(Accepted January 11 2005)


c1 *Corresponding author: Professor Maria Clelia Guerra, fax +39 51 248862, email