Detection the Aflatoxins in Food Stuff (Milk, Egg, Banana and Onion) from Three Locations (Khartoum, Omdurman and Bahri) in Khartoum State, Sudan

Introduction

Aflatoxins are group of structurally toxic compounds produced by certain strains of fungi (Asperillus flavus), such fungi produced only B aflatoxins and A parasitic; in addition they produces both B and G aflatoxins. The major aflatoxins are designated B1, B2, G1 and G2 Aflatoxin B is the aflatoxin which produces a blue color under ultraviolet while Aflatoxin G produces the green color. AFM1 produces a blue-violet fluorescence while AFM2 produces a violet fluorescence [1]. Aflatoxins are Detection the Aflatoxins in FoodStuffs (Milk, Egg, Banana and Onion) from Three Locations (Khartoum, Omdurman and Bahri) in Khartoum State, Sudan genotoxic, carcinogenic and immunosuppressive substances, and cause both acute and chronic toxicity [2].

Crop growth and its interaction with beneficiary and pathogenic and/or toxigenic microorganisms vary from year to year, mainly depending on local weather, making the agricultural sector particularly exposed to climate change [3]. These fungal metabolites are important causes of chronic toxicity from exposure via food [4].

These toxins are usually found together in various foods and feeds in various proportion. Aflatoxins M1 and Int J Biochem Physiol

M2 are oxidative metabolic product of aflatoxins B1 , and B2 produce by animals and is usually excreted in milk, urine and faces of dairy cattle and other mammalian species that have consumed aflatoxins contaminated food or feed. Aflatoxicol is reductive metabolite of aflatoxins B1 [5]. National dietary surveys are used for monitoring the food consumption and nutrient intakes of population groups and for assessing potential foodborne risks, which arise from the intake of harmful substances such as toxins or microbes, or the excessive intake of natural food components. Food risk assessment is used to characterize the potential adverse effects on health resulting from exposure to food-borne risks over a specified time period [6], in recent years, the idea of risk based food safety management has increased the need for food risk assessment. Risk assessment based food safety measures are designed to reduce risks to a target level [6]. These measures are planned in order to achieve an established level of human health protection. In order to qualify food- borne risks, an exposure assessment, as a part risk assessment, is essential. For exposure assessment, demographically and geographically representative food consumption data is needed. In most countries, Risk analysis is a powerful tool for carrying out science-based analysis and for reaching sound, consistent solutions to food safety problem. The term of risk analysis can promote ongoing improvement in public health and produce a basis for expanding international trade in food. Mycotoxins are toxic secondary metabolites produced by filamentous fungi, most commonly of the genera Aspergillus, Fusarium and Penicillium, other important producers being Claviceps and Alternaria [7].

Several hundred different mycotoxins have been discovered so far, exhibiting different structural diversity, with various chemical and physicochemical properties, but only a few present significant food safety challenges [8]. aflatoxins and ochratoxins are produced by Aspergillus sp., fumonisins, trichothecenes and zearalenone are produced by Fusarium sp., patulin is produced by Penicillium sp. and ergot alkaloids are produced in the sclerotia of Claviceps sp. They are the most frequent occurring mycotoxins with the most severe effects in humans and animals [9].

Mycotoxins remain challenging to classify due to their diverse chemical structures, biosynthetic origins and their production by a wide number of fungal species. A first approach can be to classify them according to their differences in their fungal origin, chemical structure and biological activity. Also the classification can be done according to how frequently they occur and in what amounts. This is a more complicated task because mycotoxin contamination of food and feed depends on environmental and climatic conditions, harvesting techniques, storage conditions and some others factors. Typically, the classification schemes reflect the scientific background of the person doing the categorizing. For clinicians the classification is done depending on the organ they affect: hepatotoxins, nephrotoxins, neurotoxins, immunotoxins. For cell biologists the classification is done according to generic groups such as teratogens, mutagens, carcinogens and allergens. Organic chemists tend to classify mycotoxins according to their chemical structures e.g. Lactones, coumarines, biochemists according to their biosynthetic origins such as polyketides, amino acid-derived, physicians by the illnesses, they cause such as St. Anthony's fire, stachybotrytoxicosis, and mycologists by the fungi that produce them e.g. Aspergillus toxins, Penicillium toxins [10]. The major mycotoxins are aflatoxins (AFs) [11, 12], Zearalenone (ZEN) [13] and Ochratoxins (OT) [14].

Extensive investigation of Brazilian peanut meal showed that it contaminated with aflatoxins (Daly, 2000) which had become moldy during transport. Further investigations showed that the peanut meal was heavily contaminated with the organism Aspergillus flavus, hence the name Aflatoxin [15] and that the poultry died from liver cancer since the aflatoxins were highly carcinogenic.

In particular, aflatoxins, had the highest acute and chronic toxicity of all mycotoxins [16]. The topic is of great economic and societal interest both for the quantitative and qualitative effects on crop yield and the impact on the occurrence of mycotoxins [17]. Very low Aflatoxin contamination was reported in the few studies published on wheat [18]. Indeed, new strategies supported by predictions should be adopted [19], such as biological control using a toxigenic A. flavus strains, able to displace the toxigenic populations of the fungus, as largely applied in risk areas in the USA and Africa [20].

The present study aimed to detect the amount of different types of aflatoxins in foodstuffs obtained from three different locations in Khartoum State, Sudan.

Results and Discussion

Table 1 indicated that calculate values of AFB1 (Aflatoxin bluish) in Bahri, Khartoum and Omdurman in onion were 9.58±1.12, 3.80±0.76 and 6.75±1.48 ppb, respectively. These findings indicated that the AFB1 are found in three locations only for anion crop, but it is still observed that calculated value of FB1 are not detect in Egg, Banana and Milk in three locations in Khartoum State. However, the calculated value of AFB1 in Bahri is highly significant (P<0.01) compared with maximum residue limit value (MRL) reported by Amendment Codex standard [21], whereas calculated value of AFB1 in Khartoum location is significantly low (P < 0.05) compared with maximum residue limit value (MRL) reported by Amendment Codex standard [22], While in Omdurman location is high than those findings by Amendment Codex standard [22]. The result obtained in all location (Bahri, Khartoum and Omdurman) is still lower than that reported by EFS [23]. The calculated value of AFB2 (Aflatoxin bluish) in egg and Banana for Bahri location was 1.78±0.12 and 2.70±0.32 ppb, respectively. While that of AFB2 in Khartoum for Banana was 2.18±0.67ppb, onion and milk in all locations. These findings are lower than those values reported by Amendment Codex standard, EFS [22, 23]. Therefore, the egg, banana, onion and milk are less contaminated with AFB2 in three locations. Contamination of milk, egg, onion and banana with AFB1 and AFB2 can cause potential carcinogenic effects if ingested even in small amounts [24].

It is also observed that AFG1 and AFG2 (Aflatoxin greenish) in Egg, Banana, Onion and milk are not detected in three locations. These results are reflecting that Egg, Banana, Onion and milk were free from AFG1 and AFG2; this might be due to following the proper hygienic operations during handling, transport and storage of those egg, milk, onion and banana. Therefore, those foods in three Locations in Khartoum state was less contaminated with AFG1 and AFG2.

The panel estimates that raising the maximum level could increase the risk of aflatoxin-induced cancers for consumers of peanuts and peanut-based processed products [19].

It is still observed that the calculated value of AFM

(aflatoxin in milk) for the milk in three locations (Bahri, Khartoum and Omdurman) was 2.27±0.69, 4.35±0.69 and 3.48±0.62 ppb, respectively. These results are indicated that calculated value of AFM for milk in three locations was highly significant than those values reported by AOAC [21]. It is also clearly observed that AFM are not detected in egg, banana and onion in three locations. This might be climate Change, highlighting how changes in temperature, humidity, rainfall and carbon dioxide production impact on fungal behaviour and consequently on mycotoxin production [24].

Table 1: Aflatoxin concentration (ppb) of products collected from different sites in Khartoum State and correlated with the maximum residue limit (MRL) [25]. CV (Calculated value), MD (Mean difference), and ND(Not detected).. Values are means of 6 samples ±SD. ** P<0.01, * P<0.05. Mean difference = calculated value- maximum residue limit (MRL) [22].

Conclusion

The results reflected that AFB1 in onion was observed in three locations in Khartoum State, in addition the value obtained is high. AFB2 for egg and banana in three locations are detected, except AFB2 for egg in Khartoum is not detected.AFG1 and AFG2 for egg, milk, onion and banana in three location were not detected, therefore, egg, milk, onion and banana are free from AFG1 and AFG2. In addition a high level of AFM in milk was detected in three locations in Khartoum State.