Article

Contamination with storage fungi of human food from Cameroon.

Food, Environment and Health Research Group, Faculty of Health Science, 2028, University of Johannesburg, Doornfontein Campus, 2028 Gauteng, South Africa.
International journal of food microbiology (Impact Factor: 3.01). 09/2009; 135(3):193-8. DOI: 10.1016/j.ijfoodmicro.2009.08.001
Source: PubMed

ABSTRACT In a mycological study, a total of 95 human food samples were investigated to evaluate the incidence of fungal contamination in Cameroon by conventional identification method and partly confirmed by DNA sequencing. The isolated fungal spp. were further studied to determine their toxigenic potentials. The investigation revealed the predominance of Aspergillus and Penicillium with 96% of samples contaminated with at least one species of these fungi, whereas the incidence of co-contamination of samples was 85%. Aspergillus flavus and Aspergillus parasiticus (Flavi section) were the most predominant species contaminating mainly maize and peanuts. In addition, P. crustosum and P. polonicum were the most common contaminants belonging to the genus Penicillium. On the other hand, A. ochraceus (Circumdati section) registered a low incidence rate of 5%, including other members of the Aspergillus group. Other members of the genera Rhizopus and Alternaria spp. were also registered in the study. A majority of fungal strains of A. ochraceus, A. parasiticus, P. crustosum and P. polonicum isolated were toxigenic, producing the mycotoxins tested for, while none was detected in cultures of A. fumigatus. The high incidence rate of fungi contamination coupled with their potentials in producing mycotoxins gives a strong indication that the samples tested may likely be contaminated with various mycotoxins. There is need for further study to assess the incidence of mycotoxins contamination in similar food samples.

0 Bookmarks
 · 
224 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Nuts are one of the main consumed snacks worldwide and a significant component of Iranian's diet. Natural contamination of nuts with fungus is unavoidable and is a major challenge to nuts safety and quality.
    Jundishapur Journal of Microbiology 01/2014; 7(1):e8751. · 0.78 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: A total of 420 samples were collected from agrarian households. While 51% (215/420) of the samples were contaminated with one or more toxins, the contamination rate for maize, peanuts and cassava products were 74%, 62% and 24%, respectively. The fumonisins (20-5412 g/kg), aflatoxin B1 (6-645 g/kg), roquefortine C (1-181 g/kg) and deoxynivalenol (27-3842 g/kg) were the most prevalent contaminants in maize. For peanut samples, aflatoxin B1 (6-125 µg/kg) and ochratoxin A (0.3-12 µg/kg) were the main contaminants while aflatoxin B1 (6-194 µg/kg) and penicillic acid (25-184 µg/kg) were detected in the cassava products. Exposure calculated through maize intake for fumonisin B1 and aflatoxin B1 were several folds higher (2-5 for fumonisin B1 and 104-105 for aflatoxin B1) than the health-based guidance values of 2 g/kg bw/day and 0.15 ng/kg bw/day, respectively. The study design constitute a good model which can be implemented in other Sub Saharan African countries.
    Journal of Agricultural and Food Chemistry 05/2014; · 3.11 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Fungal and mycotoxin contamination of commercial maize from South Africa were assessed. Forty maize samples were randomly collected from several maize consignment delivered to commercial feed companies in Kwazulu Natal in 2010. Fungal screenings of samples were done using the conventional method followed by DNA sequencing. Analyses were done on fungal species isolated to determine their mycotoxigenic potential, while mycotoxins analysis for fumonisin (FB), zearalenone (ZEA), aflatoxin B (AFB) and ochratoxin A (OTA) were assessed using thin layer chromatography (TLC) and high performance liquid chromatography (HPLC). The mycological investigation yielded 4 genera of which Fusarium especially F. verticillioides (88%) and F. proliferatum (73%) were predominant. Aspergillus fumigatus (45%) and A. flavus (43%) were the most prominent of Aspergillus genera while among Penicillium, P. digitatum (30%) and P. viridicatum (28%) were dominant. Other members of the genera were yeast species with incident rate of 38% and colony forming units of 2.4x10 2 cfu/g. Fifty percent of the fungal spp. isolated showed the ability to produce at least one of the mycotoxins tested. The data obtained from HPLC and TLC revealed that the maize samples were contaminated by FB, ZEA, AFB and OTA. Contamination level of mycotoxins on HPLC were found to range from 64 -1035 ppb, 0 -135 ppb, 0 -762 ppb and 0 -194 ppb for FB, ZEA, AFB and OTA, respectively. Data on TLC also showed the prevalence of FB 1 (45%) while AFB, ZEA and OTA were 33%, 30% and 25%, respectively. All samples analysed showed simultaneous occurrence of two or more mycotoxins. These findings demonstrate that maize may contribute to dietary exposure to mycotoxin with resultant health risks.

Full-text

Download
303 Downloads
Available from
Jun 5, 2014