Effect of Some Natural Products on Reduction of Aflatoxin Contamination in Peanut

Abstract

Many agriculture commodities and food – in particular peanut and its products – are vulnerable to a ttack by a g roup of fungi at diff erent stages o f handling and processing. Among various mycotoxins, aflatoxins have assu med significant concern due to their deleterious effects on h uman beings. Epidemiological studies have shown a positive correlation between aflatoxin and li ver cancer o r hepatocellular carcinoma (HCC) which has been recognized as one of the most common malignancies in sub -Saharan countries in Africa, South-East Asia and China. In Sudan, cl inical records suggested that liver cancer is high and increasing. Contamination of peanut (and its products) with more than permitted levels of aflatoxins has been a major problem, for both peanut producing and marketing countries, due to its ne gative impacts on human health and econo my. As a result of these concerns a strict quality regulations have been imposed by imported countries before they release the agriculture co mmodities consignments. Because of these regulations serious efforts are required f rom producing countries to meet the export requirements for importing countries. To eliminate aflatoxin problem several chemicals have been used to decontaminate or reduce aflatoxin in contaminated products. Most of chemicals are, however, unsafe to use because of the formation of toxic residues or the negative effects on nutrient value and physical properties of the product. For these reasons the chemical treatment is not allowed in some countries for commodities for human food. This study was designed to test the effect of some natural products on reduction of aflatoxin in peanut in order to find out a safe and practical reduction method. Samples of naturally contaminated peanut, collected f rom Khartoum Central Market, were tr eated with aradaib-tamarind water extract, white vinegar, lemon juice and carrot j uice. Aflatoxins were extracted by blending, separated by solvent extraction and further cleaned-up on a silica gel column. Quantification was carried out by reverse p hase high performance liquid chromatography with fluorescence detection by trifluoroacetic acid derivatives of aflatoxins. The analysis results showed that all pean ut samples were contaminated with aflatoxins B1 and B2. However, af latoxins G1 and G2 were not detected. The mean total aflatoxin level for untreated peanut samples is more than 50 ti mes EU permissible level for peanut used for direct consumption and more than 13 times the Codex Alimentarius maximum level for peanut intended for further processing. With the exception of carrot juice, treatments of 50g peanut with 30g and 40g doses of the experimental natural products gave promising results. Both aradaib-tamarind water extract and white vinegar showed a significant reduction (0.00) of both aflatoxin B1 and B2. Le mon juice showed also a signif icant reduction of aflatoxin B1 (0.00) and B2 (0.004) with 30g dose. However, with 40g dose it showed also a significant reduction ( 0.003) with B1 but insignificant reduction ( 0.136) with B2. The reduction of aflatoxin may be due to e ffect of acids constitu ents in tre ating products.