الفهرس 
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Abstract
Summary
Peanut are an important crop grown in Egypt for either local consumption or export to European markets. Aflatoxins contamination is a major challenge in peanut (Arachis hypogaea L.) production and trade besides posing health challenges to humans and animals.
1. Samples collection: Eighty peanut samples representing four peanut products raw and processed peanuts: roasted, salted and lebanese with spices were collected from local markets and small shops in five different governorates of Egypt (Cairo, Suez, Menoufia of North Delta and Fayoum and Luxor of south Delta) during (winter2013 to autumn2014).
2. Analysis of peanut samples:
A- Moisture content (MC%): In peanut samples varied depending on the types of peanut products, seasons and governorates. Results showed that values of moisture content of raw peanut range (0.66%to 16.66%) were higher than lebanese with spices peanut samples(1.03% to10.46% ) followed by salted peanuts (0.33% to 8.3% ) and the lowest MC% in roasted peanut(0.33% to 6.76 % ). Also , the average of MC% in winter season were(5.44%) higher than autumn(3.74%) followed by summer(3.38%) ,and spring was lowest MC%(3.28%) in samples. However ,samples collected from Suez governorate had highest MC% by average (6.71%) specially, in raw(16.66%) and lebanese with spices (10.46%) peanut samples in winter season. In other governorates the average of MC% were slightly different as Menoufia(4.03%), Cairo(3.89%), Fayoum (3.42%) and Luxor (1.76%) .
B-Mycological analysis: It was noticed that 100% peanuts samples were contaminated with filamentous fungi.
3771 isolates of four fungal genera were identified: Aspergillus spp (55.23%), Penicillium spp(19.51%) , followed by Fusarium spp (13.94%) and Rhizopus spp (11.29%).
Suez governorate had the highest percentage of fungal contamination (62.5%) followed by Menoufia (59.58%) then Cairo (55.0%), Fayoum (54.95%) and finally Luxor (43.75%).
Spring season had highest percent of fungal contamination (77.5%), while autumn season had lowest fungal contamination (60%), moderate fungal contamination in summer (70%) and winter was (64.2%).
Raw peanut was highest fungal contamination (92.1%) followed by lebanese with spice(75.4%) then roasted peanut at( 55.8%),while salted peanut was lowest fungal contamination (48.75%).
*Generally, A.niger was the highest contamination percentage (48.68%), A.flavus (19.73%), A.parasiticus (17.57%), A.oryzae (8.83%) and A.oryzae var effusus (5.18%), respectively. The most contaminated product was raw (61.7%) followed by lebanese with spices (44.5%)then roasted (32.5%) and salted (15.5%). While for locations Suez governorate was the highest contaminated (60.2%) followed by Menoufia (55.5%), Fayoum (53.8%), Cairo (52.0%) and Luxor (49.2%).
* Screening for the ability of isolated Aspergillus section flavi to aflatoxins Production: as 160 isolates only of 1066 isolates of Aspergillus section flavi could produce aflatoxins as 64 isolates of A.flavus could produce aflatoxins, and 96 isolates of
A.parasiticus. Highly aflatoxigenic fungi population in Suez governorate (66 isolates), followed by Cairo (30 isolates), Menoufia (26 isolates), then Fayoum (21isolates) and the lowest aflatoxigenic fungi population in Luxor (17 isolates).However in peanut products, raw peanut was highly contaminated with aflatoxigenic fungi(64 isolates) followed by lebanese with spices(38 isolates) then roasted peanuts (32 isolates)and the lowest aflatoxigenic fungi contamination was salted peanut (26 isolates).
C-Occurrence of aflatoxins in peanut products: The results showed 33(41.25%) of total 80 samples were contaminated with aflatoxins with concentration ranges from (3.77to 871.72μg/kg).
However the numbers of contaminated samples with B1 33(41.25%), B2 33(41.25%) , G1 18(22.5%) and G2 19(23.75%). It was noticed that winter season had the highest number of aflatoxigenic contaminated samples 11(33.33%) followed by spring season 8(24.24%) and autumn and summer season 7(21.21%),while autumn season had the highest average concentration of total AFs 85.72 μg/kg and spring season has the lowest average concentration of total AFs 49.92μg/kg.
Suez province has the highest number of aflatoxigenic contaminated peanut samples 8(24.24%) followed by Menoufia and Fayoum 7(21.21%) then Cairo 6(18.18%) and finally Luxor 5(15.15%) also Suez province has the highest average concentration of total aflatoxins 97.20 μg/kg and Luxor has the lowest average concentration of total AFs 38.26 μg/kg.
Data revealed that raw and lebanese with spices peanut products were the highest aflatoxigenic contaminated peanut
samples 11(33.33%) followed by salted peanuts 7(21.21%) and finally roasted was the lowest 4(12.12%), in the same line raw peanut samples had the highest average concentration of total AFs 112.21 μg/kg and roasted peanuts product had the lowest average concentration of total aflatoxins 26.73μg/kg, while lebanese with spices samples 80.27 μg/kg.
3.Effect of Spices on the Aspergillus flavus Growth and Aflatoxins production: Ten powder spices (clove , black pepper, cinnamon, peppermint, thyme, cardamom, cumin, ginger, onions and fenugreek) at different concentrations (4,7and 10mg /ml) were used against A.flavus in broth YES media and raw peanut.
*On broth media results recorded that clove inhibited completely the mycelial growth of the tested fungi at different concentrations. On the other hand, cumin, ginger, onions and fenugreek showed poor antifungal activity even in high concentration (10mg/ml). While black pepper , cinnamon, thyme, , peppermint and cardamom gave a graded inhibition effect at 4,7 ,10mg/ml (48.93-59.57%), ( 30.63-44.25%) , (28.93-30.63%) , (23.40-45.53%), (14.89-26.80%), respectively.
*While the effect of spices on aflatoxins production in broth media showed that clove, cinnamon, thyme and peppermint had complete inhibition activity against AFs production at different concentrations, while black pepper, cardamom and ginger had complete inhibition activity against AFs production at (10mg/ml) only. On the other hand cumin, onions and fenugreek as powder had no effect on AFs production.
*Minimum inhibitory concentration (MIC) of clove against Aspergillus flavus was recorded at 3mg/ml in YES broth medium.
*On raw peanut seeds The inhibitory effect of spices (clove, cinnamon, peppermint and thyme) on fungal growth and AFs production recorded that fungal growth decreased with increasing spices concentration .While the AFs were completely inhibited at 10mg/25ml concentration of the tested spices and at 7mg/25ml of the clove and cinnamon and reduced to 20, 30, 43.8 and 50μg/kg, with clove, cinnamon, peppermint and thyme respectively at 4mg/25ml and reduced to 22.3 and 30 at 7mg/25ml of peppermint and thyme, respectively.