Feasibility of A Novel On-Site Detection Method for Aflatoxin in Maize Flour from Markets and Selected Households in Kampala, Uganda

Abstract

In sub-Saharan Africa, there is a high demand for affordable and accessible methods for on-site detection of aflatoxins for appropriate food safety management. In this study, we validated an electrochemical immunosensor device by the on-site detection of 60 maize flour samples from six markets and 72 samples from households in Kampala. The immunosensor was successfully validated with a linear range from 0.7 ± 0.1 to 11 ± 0.3 µg/kg and limit of detection (LOD) of 0.7 µg/kg. The maize flour samples from the markets had a mean total aflatoxin concentration of 7.6 ± 2.3 µg/kg with approximately 20% of the samples higher than 10 µg/kg, which is the maximum acceptable level in East Africa. Further down the distribution chain, at the household level, approximately 45% of the total number contained total aflatoxin levels higher than the acceptable limit. The on-site detection method correlated well with the established laboratory-based HPLC and ELISA-detection methods for aflatoxin B1 with the correlation coefficients of 0.94 and 0.98, respectively. This study shows the feasibility of a novel on-site detection method and articulates the severity of aflatoxin contamination in Uganda.

Improving Health and Wealth by Introduction of an Affordable Bacterial Starter Culture for Probiotic Yoghurt Production in Uganda

“…Since the probiotic starter culture can also be used for the fermentation of cereals such as millet and corn [73,84], the scope of application can further extend. This is particularly relevant for the purpose of detoxification (reduction of aflatoxins) [54]. We envision that this concept and the direct way of working together with the local communities can also be implemented in other African countries.…”

“…[ 53,54] Binds Aflatoxin B1, thereby reducing its absorption in the intestine, and hence reducing aflatoxin associated pathogenicity.…”

Aflatoxins in Uganda: an encyclopedic review of the etiology, epidemiology, detection, quantification, exposure assessment, reduction and control

“…Maize flours from the scrutinized markets of Usafi, Nakawa, St. Balikudembe (also called Owino), Nakasero, Kireka and Kalerwe had a mean total AF of 7.6 ± 2.3 µg/kg with approximately 20% of the samples having higher than 10 µg/kg statutory AF limit while 45% of household samples had total AFabove compliance limit. The AF results from the immunosensor reportedly correlated with HPLC and ELISA results with correlation coefficients of 0.94 and 0.98 respectively [70].…”

“…Due to limited access to the aforelisted laboratory-based analytical methods, a rapid on-site AF portable immunosensor based on a glass-electroless-plated silver/cysteine platform for detection of total AF was constructed at Uganda Industrial Research Institute, plot 42A, Mukabya road, Nakawa, Kampala, Uganda by Wacoo and his teammates [101]. This electrochemical immunosensor device was subsequently validated in a penultimate study [70] which assessed the AF content of 60 maize flour samples in six principal markets and 72 samples from selected households in Metropolitan Kampala. The immunosensor was reportedly validated with a linear range of 0.7 ± 0.1 to 11.0 ± 0.3 µg/kg and limit of detection of 0.7 ± 0.0 µg/kg.…”

“…Thus, most studies reported AFB1 levels or did not distinguish between the different types [64][65][66][67][68][69]. Others, such as the validation survey of Wacoo et al [70], Muzoora et al [71], Baluka et al [72] and Wacoo et al [73] differentiated the AFs. By and large, the lack of this depth in most researches can be tailored to the overall priority of simply analysing the safety of foods and/or individuals.…”