Cyanidin can reduce the toxicity of compounds such as aflatoxin B1 and ochratoxin A. Ochratoxin A is a toxin produced by Aspergillus ochraceus and Penicillium verrucosum. Human exposure occurs mainly through consumption of improperly stored food products, mainly in from grape products. It is potentially carcinogenic to animals and humans and has been shown to be weakly mutagenic, possibly by oxidation of DNA. Acute intake of ochratoxin A is cytotoxic and suppresses the immune system. Cyanidin 3-glucoside has been shown to reduce the damage in rats exposed to the toxin . Administration with cyanidin counteracted the deleterious effects ochratoxin A. It inhibited the production of lipid hydro peroxide and prevented the DNA damage to liver and kidney cells. Russo et al. also studied the protective effect of cyandin against the toxicity of ochratoxin A. They also found that ochratoxin A caused an increase in radical oxygen species, especially after a longer period of incubation, and resulted in rupture of cellular membrane and DNA damage in cultured fibroblasts. The treatment of the cells with cyanidin 3-O-beta-D-glucoside resulted in a significant reduction of free radical species and DNA damage .
Aflatoxin B1 is a mycotoxin that is produced by Aspergillus flavus and is toxic and carcinogenic. Aflatoxins are metabolized in the liver into a very reactive epoxide, aflatoxin M1. Guerra et al tested the protective effect cyanidin glycoside against the cytotoxic activity of aflatoxin B1 and ochratoxin A on cultured liver and colon cancer cells . They found that pretreatment of the cells significantly inhibited the cytotoxicity of the two mycotoxins, as shown by a reduced production of reactive oxygen species and prevention of apoptosis. Cyanidin reduced DNA fragmentation and inhibited caspase-3 activation.
In-vitro studies demonstrate the chemopreventive action of cyanidin. Cyanidin 3-O-beta-glucopyranoside reduced the frequency of micronuclei in cultured human lymphocytes induced by the mutagens ethyl methanesulfonate, colchicine and hydrogen peroxide, but not by mitomycin C . The in-vitro micronucleus test is used in toxicological screening for potential genotoxic compounds. A micronucleus is the erratic nucleus that forms during the anaphase of mitosis or meiosis. They also found that cyanidin-3-O-beta-glucopyranoside was not genotoxic at levels up to 100 ppm. Apoptosis was induced by cyanidin 3-O-beta-glucopyranoside alone and even more under conditions in which cyanidin-3-O-beta-glucopyranoside produced anti-genotoxic effects. This suggests that cyanidin 3-O-beta-glucopyranoside may help to remove highly damaged cells.
 Di Giacomo C, Acquaviva R, Piva A, Sorrenti V, Vanella L, Piva G, Casadei G, La Fauci L, Ritieni A, Bognanno M, Di Renzo L, Barcellona ML, Morlacchini M, Galvano F. "Protective effect of cyanidin 3-O-beta-D-glucoside on ochratoxin A-mediated damage in the rat." Br J Nutr. 2007 Nov;98(5):937-43.
 Guerra MC, Galvano F, Bonsi L, Speroni E, Costa S, Renzulli C, Cervellati R. " Cyanidin-3-O-beta-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)." Br J Nutr. 2005 Aug;94(2):211-20.
 Russo A, La Fauci L, Acquaviva R, Campisi A, Raciti G, Scifo C, Renis M, Galvano G, Vanella A, Galvano F. " Ochratoxin A-induced DNA damage in human fibroblast: protective effect of cyanidin 3-O-beta-d-glucoside." J Nutr Biochem. 2005 Jan;16(1):31-7.
 Fimognari C, Berti F, Cantelli-Forti G, Hrelia P. " Effect of cyanidin 3-O-beta-glucopyranoside on micronucleus induction in cultured human lymphocytes by four different mutagens." Environ Mol Mutagen. 2004;43(1):45-52.