Mold growth is among the major causes of health impairment of cereals, in particular durum wheat (Triticum durum) for the synthesis of mycotoxins such as aflatoxins B1 and ochratoxin A (OTA), originally from poisoning in the consumer. In this context, the objectives of this work is the search and characterization of fungal strains Producers mycotoxins such as Aspergillus, Penicillium in semolina and their derivatives (traditional and industrial couscous) and detect and quantify total aflatoxins, aflatoxins B1 and ochratoxin mycotoxicologique to assess the risk associated with the consumption of these foods. In this regard, our work focuses on mycological and mycotoxicologique study of semolina and couscous deemed most commercialized in the town of Bechar-Algeria after a socio-economic survey. The mycological study testifies the high degree of pollution of our samples by Aspergillus, Penicillium. The expertise of genera reveals the high degree of invasion of our samples by Aspergillus, Penicillium. The examination of fungal procession characterizing our samples shows a very high index of distribution, or of fidelity of Penicillium 43.75% of our sample and 28.38% Aspergillus. The presence of these species is evidence that our samples have been abused, but especially poorly stored; should be noted the involvement of the genera Alternaria 7.10%, Fusarium 13.70%. Thin-layer chromatographic (TLC) analysis revealed that 50% of Aspergillus flavus-parasiticus strains were aflatoxin G-producing and aflatoxin B-free in our samples. Of the Aspergillus ochraceus strains 50% were OTA producers. The presumption of toxicity of the various samples appeared positive on TLC. The test of Elisa has confirmed the presence of the OTA in our samples, the analysis of its results shows that the majority of the rates of OTA taken on our analyzed samples follow the European standard, these rates are between 1.01 and 1.9, except for one sample (couscous) which has shown a rate much higher than the standard recommended by the regulation (> 100 ppb), the samples of semolina had a rate of OTA lower than the beginning of the detection (1 ppb). The results of the presence of AFB spread out between 4.93 ppb and > 40 ppb. The antifungal activity of the resin of Boswellia carterii was tested on the following strains: Aspergillus niger, Aspergillus flavus, Penicillium expansum. And kneaded according to the technique of diagonal growth on intermediate solid medium (PDA). The results showed that the yield of the aqueous extract varied between 96.2 and 99.8%. The results of the extracts also showed activity against the fungi studied 48.6% and 96.2%.