Antioxidative properties, phenolic compounds, and in vitro protective efficacy of multi-herbal hydro-alcoholic extracts of ginger, turmeric, and thyme against the toxicity of aflatoxin B on mouse macrophage RAW264.7 cell line.

Aflatoxin B (AFB), the most potent toxic and carcinogenic secondary fungal metabolite, has frequently been reported in food/feed. Nowadays, herbal extracts are considered safe dietary additives to reduce the toxicity of such compounds. The protective capability of various combinations of hydro-alcoholic extracts (HAEs) of ginger, turmeric, and Shirazi thyme, against the toxicity of AFB on the RAW264.7 cell line was investigated. The RAW264.7 cells were exposed to six different concentrations of AFB (0.09, 0.18, 0.37, 0.75, 1.5, and 3 μg mL) for 48 h to determine the IC of AFB. AFB was estimated to have an IC of 1.5 μg mL for RAW264.7 cells. Then, the cells were simultaneously incubated with 1.5 μg mL AFB and the HAEs for 24 h. The HAEs significantly reduced the toxicity of AFB in RAW264.7 cells. HAE of Shirazi thyme showed the highest amount of total phenol content (TPC) and the highest DPPH• activity. In addition, a combination of ginger, turmeric, and Shirazi thyme extract showed the highest antioxidant activity. Rutin, quercetin, and apigenin were the main phenolic components of ginger HAE. A significantly positive correlation was observed between TPC of hydro-alcoholic extract with ferric reducing antioxidant power (FRAP) and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) values. Consequently, the simultaneous consumption of such extracts is recommended to protect the cells against dietary toxins.