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 B₁ on mouse macrophage RAW264.7 cell line

Aflatoxin B₁ (AFB₁), 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 AFB₁ on the RAW264.7 cell line was investigated. The RAW264.7 cells were exposed to six different concentrations of AFB₁ (0.09, 0.18, 0.37, 0.75, 1.5, and 3 μg mL^-1) for 48 h to determine the IC₅₀ of AFB₁. AFB₁ was estimated to have an IC₅₀ of 1.5 μg mL^-1 for RAW264.7 cells. Then, the cells were simultaneously incubated with 1.5 μg mL^-1 AFB₁ and the HAEs for 24 h. The HAEs significantly reduced the toxicity of AFB₁ 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.