Bibliothèque de L'IMIST/CNRST

PH.D Université Mohammed V 2016

This work aims to validate an-in house method «QuEChERS» for the analysis of ochratoxin A (OTA) in food and feed by using liquid chromatography coupled to fluorimeter detection, and the optimization of the extraction procedure for solvent choice. The validated method was applied for the first time to assess the presence of ochratoxin A (OTA) in samples of poultry feeds and rice marketed in Morocco. During this investigation, we also investigated the presence of emerging Fusarium mycotoxins (Beauvericin (BEA), Enniatins (ENs) and Fusaproliferin (FUS)) in rice commercialized in Morocco. Results of the validation of the method showed that methanol gives the best recovery rate and that OTA was present in 30.6% of sixty-two samples of poultry feeds purchased from farms in Rabat, Salé and Témara areas. On the other, the validated method was successfully applied to the analysis of seventy samples of rice from six cities of Morocco: Rabat, Errachidia, Kenitra, Mohammedia, Tangier and Casablanca. Results showed that 42.8% of the samples were contaminated with OTA. Concerning the presence of emerging mycotoxins, the investigation of seventy samples of rice from six cities in Morocco showed that BEA was present in 75.7% of the samples, and the concentrations of the BEA vary between 3.8 and 26.3 mg /kg. In addition, the frequency of contamination of ENs and FUS were 50% and 4.3% respectively. Among ENs, ENB was the most common found, while ENB1, ENA and ENA1 were found with low percentages. The highest contamination level of ENs was reported in a sample of rice sampled from Kenitra city. This is the first report on the presence of emerging mycotoxins in rice available in Morocco.