Use of Natural Dietary Spices for Reclamation of Food Quality Impairment by Aflatoxin

Certain natural dietary spices, in addition to their use in food flavoring and preservation, have the ability to detoxify or degrade a wide range of chemical carcinogens. In the present study, aqueous extracts of judiciously selected natural dietary spices were evaluated for their ability to degrade aflatoxin B1 (AFB1). A total of 9 spices including garlic (Allium sativum), ginger (Zingiber officinale), black cumin (Nigella sativum), clove (Syzygium aromaticum), sacred basil (Ocimum basilicum), lemon grass (Cymbopogon citratus L. (DC) Stapf)), thyme (Thymus schimperi), fenugreek (Trigonella foenum-graecum), and lemon traditionally used by the Ethiopian Community for food flavoring and preservation were considered. Aflatoxin degradation efficacy of the spice extracts was studied through determination of the toxin in extract-treated and nontreated samples using LC-MS/MS. The degradation was characterized by electrochemical methods based on the characteristic oxidation peak of phenolic hydroxyl resulting from the degradation of the toxin after treatment with the extracts. Of the various spices, garlic showed the highest 35.8% (30 min) to 61.7% (1 hr) in spiked and 46.7% (30 min) to 68.3% (1 hr) and real-sample (contaminated maize) treatment reduction followed by lemon 34.2% (30 min) to 56.0% (1 hr) in spiked and 41.1% (30 min) to 60.6% (1 hr) in real-sample treatment at 25°C. The level of reduction was higher in real-sample treatment than that in spiked. This suggests adsorptive contribution by the matrix in addition to the chemical degradation. The current findings revealed nonobvious benefits of the use of natural dietary spices as effective solution for AFB1 degradation and decontamination of food.