الفهرس 
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Abstract
Introduction: In contemporary life, there is avast prevalence of aflatoxins in different kind of food. Most aflatoxins are chemically and heat stable in the range of food processing. Therefore, may increase the consumption of food contaminated with aflatoxins are source of serious problems for human health and have adverse impact on economic worldwide. The use of chemical , physical and biological detoxification methods , may increases the efficacy of toxins degradation in foods . Aim of this study: The current work investigated techniques which developed to detoxify contaminated food by adding natural additives to biscuits such as dried blueberries ,wheat bran and nano-charcoal.Material and methods: This study was undertaken to examine the possible toxic effects on rats infected with aflatoxins in vivo. All experimental rats was assigned into 5 similar groups, 6 rats in each group. Rats in the 1st group (G1) were fed a commercial pelleted diet without any supplementation (negative control), while those in the 2nd, 3rd, 4th and 5th groups was fed on toxic diet (peanut natural contaminated with toxin at the level of 20 ppb total aflatoxin (ng/g diet) as positive control (G2), 50% toxic diet (peanut natural contaminated with toxin) +50% biscuit with berries (G3), 50% toxic diet (peanut natural contaminated with toxin) + 50% biscuit with bran (G4) and 50% toxic diet (peanut natural contaminated with toxin) + 50% biscuit with nano-charcoal (G5),respectively, for 7 weeks as a treatment period. Investigate the efficiency of adding natural additives to biscuits such as dried blueberries or wheat bran and nano-charcoal against the toxicity in rats infected with aflatoxins in vitro and in vivo which may lead to decrease their dangerous effects. The study also demonstrated the effect of natural detoxifying agents on the organoleptic properties , chemical and shelf-life of biscuits. Results: Chemical analysis , sensory evaluation and microbiological examination of biscuits: Adding dried blueberries and wheat bran to biscuit increased fiber content ( 5.43 , 6.00%) and energy (504.63, 525.00%) , respectively while adding of nano-charcoal at ratio of 0.25% and 0.5% increased ash content 2.18 and 4.66%, respectively.High ratios of 20% of dried blueberries and 0.5% of nano-charcoal to biscuit resulted in bitter and dusty taste , respectively. With regard to color , addition of dried blueberries and nano-charcoal resulted in dark and light green colors respectively, on otherhand, addition of 5% of wheat bran resulted in hard texture (12.9 degree) and low crispiness (12.8 degree).No TBC , moulds and yeasts were detected in all biscuit samples except samples with dried blueberries for TBC after storage for 2 months .The counts of moulds and yeasts started to be detected and counted after 4 months of storage of biscuits with different additives.Increasing ratios of different natural additives reduced TBC , moulds and yeats in all samples after storage for 4 months .The lowest count of bacteria was noticed with biscuit with nano-charcoal after 4 months of storage 10 ×102 cfu̸ g while no moulds and yeasts were detected. Direct effect of natural additives on detoxification of total aflatoxins (in vitro): Addition of different natural additives as detoxifying agents (dried blueberries, nano-charcoal and wheat bran) had positive effect on the reduction of AFs in all samples . Effect of addition of dried blueberries or wheat bran or nano-charcoal to biscuit on rats infected with aflatoxins: Generally, the results revealed significant (P<0.05) effect of feeding biscuit supplemented with wheat bran or nano-charcoal or dried blueberries on concentration of HB, RBCs, WBCs in all groups. Hemoglobin (HB) concentration showed the highest significant (P<0.05) value (13.77 mg/dl) for G1( -ve group) , while the lowest significant (P<0.05) value (12.47 mg/dl) was recorded for G2 (+ve group). RBCs concentrations in blood serum were significantly decreased by dietary treatments, being the lowest significant (P<0.05) values in rats fed G2, (5.85 106/mm3) .While, the highest value was recorded for G1 group(6.52 106/mm3) in descending order. Positive group (G2+ve) fed on contaminated aflatoxin diet only without any additives achieved significantly ( P<0.05) reduction in serum total protein , albumin and globulin by (23.48, 26 and 35.82%) compared with the control group (G1-ve).There were significantly increased (P<0.05) in creatinine and urea in (G2+ve) compared with control (G1-ve). The G3 is the best group which treated with dried blueberries that close to normal range followed by G4 (group which treated with wheat bran) and G5 ( group which treated with nano-charcoal) .The highest level of blood glucose was noticed in control ( G1-ve) group which scored a mean of 120.67 mg / dl. Followed by (G3) group (111.67 mg / dl) ,While the lowest level was scored for control positive group (G2+ve) which scored a mean of 97.67 mg / dl. In conclusion, biochemical analysis and histological investigations have , provided an evidence for the protective effect of natural additives in rats infected with AFs and fed on all biscuit samples . Conclusion: Natural additives are preferable than other detoxifying agents due to its high nutritive value as well more safe for human. The foodstuff is contaminated with AFs , needs to be handled properly and controlled both before and after harvest.To follow every possible steps to minimize the risk of high exposure to AFs .Studies should be carried out on the induction of mycotoxin detoxification pathways or inhibition of mycotoxin production in cereals.