This study was conducted to test the antioxidant and anticancer activities of New Zealand Manuka honey and Thyme honey. The antioxidant activity of these two types of honey were tested by using two antioxidant assays, 2, 2-diphenyl-1-picrylhydrazyl free radical assay (DPPH), and Cupric Ion Reducing Antioxidant Capacity assay (CUPRAC), to test the free radical scavenging capacity and the bis (neocuproine) copper (II) cation (Cu (II)-Nc) reducing ability of tested honeys respectively. The anticancer activity concerning these two kinds of honey against Caco-2 cells was evaluated by MTT (3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) cell proliferation assay.

The experiment results demonstrated that both antioxidant and anticancer activities of tested honeys are time- and concentration-dependent. Both the DPPH radical scavenging capacity and cupric ion reducing capacity of Thyme honey are greater than those of Manuka honey at the same concentrations, incubation time and solvents. Similarly, the anti-proliferative effect of Thyme honey is 1.5-2-fold more potent than that of Manuka honey in Caco-2 cells after treatment for 48 and 72 hours. Therefore, along with the anticancer activity, the strong antioxidant capacities of tested honeys make them promising sources for further extraction/development of anticancer and chemopreventive compounds. Further preclinical and clinical studies are warranted to elucidate the therapeutic values of any specific extracts of tested honeys.