Abstract:
Monitoring mycotoxin contamination in foods and feeds is important in both
human's and animals' health and it is of concern in the regulation of mycotoxins in
foods and feeds worldwide. Out of all the contaminants found in food and feeds,
mycotoxins are one of the extensively studied contaminants. Mycotoxins are
secondary metabolites produced by a wide range of filamentous fungi. Mycotoxins
are commonly found in agricultural commodities and derivate. Exposure to high
concentrations of mycotoxins may have a toxicological effect on both animals and
humans.
As mentioned, the major sources of mycotoxin contamination are agricultural
commodities and derivative products. For this reason, an ultra-high performance
liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS)
method was optimised and validated for the simultaneous determination of patulin,
aflatoxins B1, B2, G1, and G2 in vegetable samples. The optimised UHPLC MS/MS method was validated by evaluating the method characteristics such as
linearity, limits of detection (LODs), limits of quantification (LOQs), accuracy, and
precision. The method exhibited good linearity and it was sensitive with good
recoveries.
The prevalence and occurrence of fungal and mycotoxin contamination on
vegetables from South Africa were determined. A total of hundred and twenty-one
vegetable samples such as Carrots, cucumber, onions, potatoes, and sweet
potatoes were collected from five South African provinces namely Limpopo
Province (LP), Gauteng Province (GP), KwaZulu-Natal (KZN), Eastern Cape
Province (EC) and Western Cape Province (WC). The isolated fungal species
from the vegetable samples belonged to the Aspergillus, Fusarium, and Penicillium
genera. The most predominant fungal isolate in the vegetable samples was
Aspergillus fumigatus. Furthermore, the vegetable samples from KZN province
were the most susceptible to fungal contamination.
Patulin was detected in carrots and peppers. It was found that the level of patulin
in these samples was below the LOQ. The presence of patulin in vegetable
samples demonstrated its prevalence in the food chain. Thus, it is important to set-
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up guidelines for the monitoring of mycotoxins which can be achieved by the use
of robust, sensitive, and simple analytical methods.
The cytotoxic effect of patulin on humans was evaluated. The results
demonstrated that the decrease in the viable cancer cell is dependent on the
concentration of patulin. Although the results of this study demonstrated that
patulin has the potential to reduce cancer cell lines, prolonged consumption of
patulin could have a negative impact on human health.
