Fumonisin contamination of maize (Zea mays) in aflatoxin ‘hot’ zones in eastern province of Kenya (original) (raw)
Related papers
African Journal of Education,Science and Technology, 2020
Maize serves as a staple food in many Sub-Sahara African (SSA) Countries. It is mostly susceptible to mycotoxins including aflatoxin and fumonisin contamination. Fumonisins are produced by the Fusarium species, predominantly Fusarium verticillioides. Fumonisins' health hazards are documented in many parts of the world. However, few studies exist on fumonisin contamination in maize locally. The presence of Fusarium species and the associated fumonisin contamination of maize grown in Rift Valley and Lower Eastern regions of Kenya were assessed. Maize samples were collected from randomly selected households in three Counties from each of the two regions. Isolation and characterization of Fusarium species was done using Daniel et al., (2011) protocol. Envrologix Quick Tox Kit was used to quantify fumonisin levels. Aspergillus species was the most prevalent fungi species isolated (50.3%) followed by Fusarium species (39.3%) with F. verticillioides accounting for 80.8% of all Fusarium spp. Of the 200 samples analyzed, 133 (65.5%) had fumonisin levels below the level of detection (< 0.1 ppm), 63 (31.5%) had fumonisin level of between 0.1 ppm-4.0 ppm and 4 (2.0%) sample had fumonisin levels of more than 4.0 ppm. Lower Eastern Region had higher proportion of samples with detectable fumonisin levels compared to Rift Valley Region (55.4% vs 11.1%). In conclusion Fusarium verticillioides commonly associated with fumonisin contamination of maize was a common fungus isolated in the study regions. It also showed that some of the maize samples consumed by the respondents have fumonisin levels that are above the internationally accepted levels. These results suggest that people are likely to be exposed to fumonisins that has been associated with adverse health hazards.
Assessment of aflatoxin and fumonisin contamination of maize in western Kenya
Phytopathology, 2015
We conducted a survey of aflatoxin and fumonisin in maize in western Kenya. In a regional survey of aflatoxin conducted in 2009 across three agroecological zones within three administrative regions, milled maize samples were collected from 985 patrons of 26 hammer mills. Aflatoxin contamination was detected in 49% of samples and was above the regulatory (10 ppb) in 15% of the samples overall; 65% of samples from a drought-prone area were over the limit. In a detailed survey in Bungoma County, we investigated aflatoxin and fumonisin contamination in four popular maize varieties at harvest and after two and four months' storage. We collected whole-grain samples from farmers' storage sheds and milled samples from patrons of local mills. Mean aflatoxin contamination was identical for storage sheds and mills at 2.3 ppb. Forty-one percent of the samples from mills had detectable aflatoxin, with 4% over the regulatory limit, whereas 87% had detectable fumonisin, with 50% over the r...
Incidence of Fusarium spp. in selected maize genotypes grown in Nakuru County, Kenya
PLANT-ENVIRONMENT INTERACTION, 2022
Maize (Zea mays L.) is a staple food crop for people in Kenya. It is usually contaminated by fungi Fusarium verticillioides that produces mycotoxins, Fumonisins (FBs). In Kenya there is limited data on distribution of different Fusarium species in various maize genotypes. The research aimed at establishing the percentage incidence of Fusarium species attacking selected maize genotype in Nakuru County, Kenya. Methods used was a purposive sampling in collecting, maize kernels showing no symptoms of Fusarium infection from 277 farmers’ in Molo and Njoro Sub-Counties. Fusarium species were identified using morphological characteristics (Colour and spores on potato dextrose Agar). Results showed, farmers in the study area grow hybrid maize susceptible to Fusarium ear rot. Highest % incidence was recorded in maize genotype H629 and H626 (95.83% and 90.28 % incidence respectively). Lowest % incidence was in Pioneer Maize (43.33%). Conclusion from this research was; Fusarium spp. infect all maize genotypes in Nakuru County, Kenya, Fusarium ear rot infecting symptomless maize kernels is caused by various Fusarium species. This research will enlighten farmers, public and Agricultural officers on maize infestation by Fusarium fungi and percentage incidence on the genotypes, hence need to grow genotypes with minimal percentage incidences of Fusarium spp. Plant-Environment Interactions Electronic copy
Incidence of Fusarium Spp. In Selected Maize Genotypes Grown in Nakuru County, Kenya
PLANT-ENVIRONMENT INTERACTION, 2022
Maize (Zea mays L.) is a staple food crop for people in Kenya. It is usually contaminated by fungi Fusarium verticillioides that produces mycotoxins, Fumonisins (FBs). In Kenya there is limited data on distribution of different Fusarium species in various maize genotypes. The research aimed at establishing the percentage incidence of Fusarium species attacking selected maize genotype in Nakuru County, Kenya. Methods used was a purposive sampling in collecting, maize kernels showing no symptoms of Fusarium infection from 277 farmers’ in Molo and Njoro Sub-Counties. Fusarium species were identified using morphological characteristics (Colour and spores on potato dextrose Agar). Results showed, farmers in the study area grow hybrid maize susceptible to Fusarium ear rot. Highest % incidence was recorded in maize genotype H629 and H626 (95.83% and 90.28 % incidence respectively). Lowest % incidence was in Pioneer Maize (43.33%). Conclusion from this research was; Fusarium spp. infect all maize genotypes in Nakuru County, Kenya, Fusarium ear rot infecting symptomless maize kernels is caused by various Fusarium species. This research will enlighten farmers, public and Agricultural officers on maize infestation by Fusarium fungi and percentage incidence on the genotypes, hence need to grow genotypes with minimal percentage incidences of Fusarium spp.
Infection of maize by Fusarium species and contamination with fumonisin in Africa
2004
Fusarium is one of the major fungal genera associated with maize in Africa. This genus comprises several toxigenic species including F. verticillioides and F. proliferatum, which are the most prolific producers of fumonisins. The fumonisins are a group of economically important mycotoxins and very common contaminants of maize-based foods and feeds throughout the world. They have been found to be associated with several animal diseases such as leukoencephalomalacia in horses and pulmonary oedema in pigs. Effects of fumonisins on humans are not yet well understood. However, their occurrence in maize has been associated with high incidences of oesophageal and liver cancer. Infection of maize by Fusarium species and contamination with fumonisins are generally influenced by many factors including environmental conditions (climate, temperature, humidity), insect infestation and pre-and postharvest handling. Attempts to control F. verticillioides and to detoxify or reduce fumonisin levels in maize have been undertaken. However, more research studies are urgently needed in order to understand more about this toxin. Fumonisins are less documented because they are recently discovered mycotoxins compared to aflatoxins. To date in Africa, apart from South Africa, very little information is available on Fusarium infection and fumonisin contamination in maize. It is a matter of great concern that on this continent, millions of people are consuming contaminated maize and maize-based foods daily without being aware of the danger.
Food Additives and …, 2008
This study determined maize-user practices that influence the presence of fumonisin 3 and aflatoxin contamination of maize in food consumed in the rural areas of Tanzania. 4 Samples of the 2005 maize harvest in Tanzania were collected from 120 households 5 and examined for fumonisins and aflatoxins. Information on whether the maize was 6 sorted to remove defective (visibly damaged or mouldy) maize prior to storage and 7 whether the damaged and mouldy maize or the non-dehulled maize was used as food 8 was also collected. Also, the percentage of defective kernels in the samples was 9 determined. Ninety percent of the households sorted out defective maize, 53% 10 consumed the defective maize and 30% consumed non-dehulled maize. In 52% of the 11 samples, fumonisins were determined at levels up to 11,048 µg/kg (median, 363 µg/kg) 12 and in 15% exceeded 1000 µg/kg; the maximum limit (ML) for fumonisins in maize for 13 human consumption in other countries. Aflatoxins were detected in 18% of the samples 14 at levels up to 158 µg/kg (median, 24 µg/kg). 12% of the samples exceeded the 15 Tanzanian limit for total aflatoxins (10 µg/kg). Aflatoxins co-occurred with fumonisins 16 in 12% of the samples. The percentage defective kernels (mean, 22%) correlated 17 positively (r=0.39) with the fumonisin levels. Tanzanians are at risk of exposure to 18 fumonisins and aflatoxins in maize. There is a need for further research on fumonisin 19 and aflatoxin exposure in Tanzania to develop appropriate control strategies. 20
Euphytica, 2017
Fusarium verticillioides and Aspergillus flavus cause Fusarium ear rot (FER) and Aspergillus ear rot (AER) of maize, respectively. Both pathogens are of concern to producers as they reduce grain yield and affect quality. F. verticillioides and A. flavus also contaminate maize grain with the mycotoxins fumonisins and aflatoxins, respectively, which has been associated with mycotoxicosis in humans and animals. The occurrence of common resistance mechanisms to FER and AER has been reported. Hence, ten Kenyan inbred lines resistant to AER and aflatoxin accumulation were evaluated for resistance to FER, F. verticillioides colonisation and fumonisin accumulation; and compared to nine South African lines resistant to FER and fumonisin accumulation. Field trials were conducted at three localities in South Africa and two localities in Kenya. FER severity was determined by visual assessment, while F. verticillioides colonisation and fumonisin content were quantified by real-time PCR and liquid chromatography tandem mass spectrometry, respectively. Significant genotype x environment interactions was determined at each location (P B 0.05). Kenyan inbred CML495 was most resistant to FER and F. verticillioides colonisation, and accumulated the lowest concentration of fumonisins across localities. It was, however, not significantly more resistant than Kenyan lines CML264 and CKL05015, and the South African line RO549 W, which also exhibited low FER severity (B5%), fungal target DNA (B0.025 ng lL-1) and fumonisin levels (B2.5 mg kg-1). Inbred lines resistant to AER and aflatoxin accumulation appear to be promising sources of resistance to F. verticillioides and fumonisin contamination.
Prevalence of aflatoxin and fumonisins (B 1 + B 2 ) in maize consumed in rural Malawi
Toxicology Reports
A study was carried out to assess levels of contamination of aflatoxins and fumonisins (B 1 + B 2) in maize produced, stored and consumed in rural households in Malawi. A total of 9 districts were selected across the country representing 3 districts from each of the Northern, Central and Southern regions respectively. Households were selected at random in each district where 10 maize samples were collected for laboratory analysis. Aflatoxins and fumonisins were analyzed using a single step lateral flow immunochromatographic assay based on a competitive immunoassay format. The detection limit for aflatoxins was 2 g/kg with a quantitation range of 2-150 g/kg and that for fumonisins was 1 mg/kg with a quantitation range of 1-7 mg/kg. It was found that samples in the Southern region were highly contaminated, with the Chikhwawa district having high levels of both aflatoxins and fumonisins in maize. The Northern region had the least contamination. The maximum detected amount of aflatoxins was 140 g/kg. The maximum detected amounts of fumonisins was 7 mg/kg. About 20% of maize samples exceeded the tolerable maximum limit for aflatoxins in Malawi. Aflatoxins and fumonisins were found to co-occur with contamination levels exceeding 100 g/kg for both aflatoxins and fumonisins.