Banca de DEFESA: MARTINHO GAMAS DINIS MARTINHO
Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.STUDENT : MARTINHO GAMAS DINIS MARTINHO
DATE: 29/06/2023
TIME: 13:30
LOCAL: Sala 06 Faculdade de Farmácia
TITLE:
OCCURRENCE OF AFLATOXINS B1, B2, G1 AND G2 IN CORN FLOUR PRODUCED IN NAMPULA, MOZAMBIQUE AND THEIR CARCINOGENIC RISK ASSESSMENT
KEY WORDS:
Mycotoxins; Maize products; Risk assessment; Mozambique, Food security.
PAGES: 85
BIG AREA: Ciências Agrárias
AREA: Ciência e Tecnologia de Alimentos
SUBÁREA: Ciência de Alimentos
SPECIALTY: Avaliação e Controle de Qualidade de Alimentos
SUMMARY:
Introduction: Aflatoxins are compounds produced by the fungi Aspergillus flavus and Aspergillus parasiticus in countries with hot and humid climates. They can contaminate cereals, including maize which is a staple diet in African countries such as Mozambique. These cause serious problems in human and animal health. In sub-Saharan Africa, estimates of dietary exposure to aflatoxins exceed 100 ng/kg bw/day. The incidence of hepatocellular cancer (HCC) is 46.000 cases/year. Mozambique has the highest rate of HCC in the world. Since corn is a food that provides 80% of daily kilocalories for the rural population of Mozambique, it is necessary to evaluate the occurrence of aflatoxins and the carcinogenic risk of exposure to these contaminants. In chapter I of this study, a theoretical foundation on the evolution of the concept of mycotoxins is presented and, finally, the evaluation of the carcinogenic risk is discussed. In chapter II, it is presented the report of the investigation of the occurrence of these contaminants in maize flour produced and commercialized in the city of Nampula, Mozambique and its carcinogenic risk evaluation.
Objectives: To verify the occurrence of aflatoxins B1, B2, G1 and G2 in maize flour produced and commercialized in Mozambique in the period from January to March 2022 and assessment of carcinogenic risk due to its consumption.
Methodology: Maize flour samples (n=30), were collected from five factories. For humidity analysis, two grams of the sample was weighed into a previously dried and weighed porcelain capsule. The capsule was placed in an oven at 105ºC until it reached constant mass. The aflatoxin contents were determined by high performance liquid chromatography (HPLC) with fluorescence detector after extraction in immunoaffinity columns and derivatization with trifluoroacetic acid. The daily intake was estimated according to the proposal of Jardim and Caldas (2009). The carcinogenic risk assessment was based on the calculation of the Margin of Exposure (MOE) for two distinct scenarios: men and women.
Results and Discussion: The mean moisture content in the collected samples was 10.5% ± 0.79, ranging from 9.1% to 12.2%. Aflatoxins B1, B2, G1 and G2 were detected in 20% of the samples (n=6), and in 23.3% (n=7) of them had contamination of at least two or three of the aflatoxins. In 56.7% (n=17), of the samples no AFs were detected. The contamination of AFB1 ranged from 0.25 to 0.35 ug.kg-1, and the levels of total aflatoxins ranged from 0.55 and 1.05 ug.kg-1, with a mean of 0.89 ug.kg-1being below the MRLs (10 ug.kg-1and 4 ug.kg-1) for Mozambique and the European Union, respectively. The calculated MOE for men was 243 and for women 231, thus being many times below the negligible risk cutoff point which is 10,000.
Conclusions: Consumption of maize flour in Mozambique poses a potential risk of hepatocellular carcinoma from aflatoxin exposure, due to the high consumption of this food product that is a staple of the diet in most African countries.
COMMITTEE MEMBERS:
Presidente - 2181841 - JOSE ANTONIO MENEZES FILHO
Externa ao Programa - 2360341 - LAISE CEDRAZ PINTO MATOS - UFBAExterna à Instituição - IZABELA MIRANDA DE CASTRO - EMBRAPA