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1.
Article in English | MEDLINE | ID: mdl-38778671

ABSTRACT

This study presents the results of aflatoxin contamination of maize and groundnuts in major markets in Accra and assesses the population's exposure to aflatoxins. Raw maize and groundnuts from 6 major markets in Accra were sampled and analysed for their aflatoxin content. A total of 92 samples comprising 48 maize and 44 groundnuts were analysed using high-performance liquid chromatography, after extraction with methanol/water and cleanup on an immunoaffinity column. Total aflatoxins were quantified in 98% of the maize samples and 70% of the groundnut samples, with concentrations ranging from 0.60 to 1065 µg/kg and 0.20 to 627 µg/kg, respectively. Exposure assessment showed an estimated daily intake of 0.436 µg/kg bw/day and 0.0632 µg/kg bw/day for maize and groundnut consumption, respectively, suggesting significant health risks for consumers. The high prevalence and concentrations of aflatoxins call for an urgent need for measures to control exposure of the Ghanaian population.

2.
JMIR Dermatol ; 6: e44441, 2023 Jul 12.
Article in English | MEDLINE | ID: mdl-37632928

ABSTRACT

BACKGROUND: Adolescents who make up a vast majority of the secondary school population are at a stage at which they are largely affected by acne. This condition, which is widely visible and easily recognized by peers, has numerous misperceptions surrounding it, which may influence attitudes toward people affected by it. There is a paucity of information on the prevalence of acne and how adolescents in Jos, Nigeria, view the condition. OBJECTIVE: This study aimed to determine the prevalence of acne, perceived risk factors, and the accuracy of self-report among adolescents in Jos, Nigeria. The study also sought to understand perceptions surrounding acne in this age group. METHODS: This descriptive cross-sectional study was conducted among adolescents attending private and public secondary schools in Jos, Nigeria. In total, 482 students were recruited through a multistaged stratified random sampling method. A self-administered semistructured questionnaire was used to collect information on history of acne, perceptions of causes, and the attitude toward those who have the condition. All participants were examined for the presence of acne. Univariate, bivariate, and multivariate analysis were conducted using SPSS (version 26; IBM Corp). RESULTS: The self-reported prevalence of acne was 44% and that upon clinical examination was 55%. Self-report showed a moderate degree of agreement with clinical diagnosis (Cohen κ=57.3%; P<.001). Predictive factors for the presence of acne in general were age of ≥15 years (odds ratio [OR] 1.79, 95% CI 1.12-2.87; P=.02), being in a private school (OR 2.17, 95% CI 1.38-3.42; P=.001), and being in a senior secondary class (OR 2.14, 95% CI 1.32-3.47; P=.002). The female gender (OR 3.03, 95% CI 1.64-5.61; P=.001) and religion (OR 3.24, 95% CI 1.27-8.24; P=.02) were predictive for acne only among adolescents aged <15 years, while a positive family history was predictive in those aged ≥15 years (OR 2.04, 95% CI 1.15-3.61; P=.02). A distinct perception and attitude pattern surrounding acne was observed, as a significant proportion (84/131, 64.1% vs 47/131, 35.9%; P=.02) of those who related acne to a biological phenomenon had acne themselves; however, the belief that acne is caused by skin lightening practices was significantly more common in those without acne (19/28, 67.9%) than in those with acne (9/28, 32.1%; P=.01). One-fourth of the adolescents (n=122, 25.3%) had no idea of the possible causes of acne. CONCLUSIONS: Though acne is a prevalent skin condition among Nigerian adolescents, many misperceptions and unfavorable attitudes surround acne and persons affected by the condition. Our findings have revealed the need to work with the school health program to educate the general adolescent population about acne, to refer and manage teenagers with acne.

3.
Curr Dev Nutr ; 7(2): 100030, 2023 Feb.
Article in English | MEDLINE | ID: mdl-37180082

ABSTRACT

Background: Inadequate infant and young child feeding (IYCF) practices in low income countries contribute to poor child growth and development. Objectives: To assess IYCF practices and mycotoxin contamination in complementary food ingredients across 2 seasons in Kongwa District, Tanzania. Methods: Early feeding practices in 115 rural households from 25 villages in Kongwa District, Dodoma region, Tanzania, were assessed. The primary caregiver for the index child (6-18 mo of age) was interviewed using a structured dietary questionnaire at recruitment (October/November 2017), and revisited 6 mo later. The questionnaire included questions on typical food consumption in the past 24 h. This study reports 7 of the revised and new IYCF indicators, including minimum dietary diversity (MDD). Aflatoxins (AF) and fumonisins (FUM) were analyzed in complementary food ingredients for pooled household samples to broadly establish patterns of contamination at the village level. Results: The MDD was not met for 80% of infants at recruitment (survey 1) as compared with 56% in survey 2 (P < 0.05). Changes in MDD between the 2 surveys were dependent on season but not age. Maize was consumed by >90% of households in both surveys, whereas groundnut was consumed by 44% and 64% of households in surveys 1 and 2, respectively. AF concentrations in maize and groundnuts were found to be higher in survey 1 than in survey 2. Overall, AF exceeded the legal limit in 18% of maize and 61% of groundnut pooled samples in both surveys. Maize was also contaminated with significant FUM concentrations. Conclusions: Poor diets were common among children in Kongwa District. Reliance on maize and groundnuts exposes this vulnerable age group to AF (also to FUM in maize). Inadequate diet and exposure to AF and FUM have separately been linked to linear growth retardation. Low diet diversity and mycotoxins contamination are plausible causes for poor growth and development among infants in Central Tanzania. Curr Dev Nutr 20XX;x:xx.

4.
Plant Direct ; 5(8): e342, 2021 Aug.
Article in English | MEDLINE | ID: mdl-34458666

ABSTRACT

Water deficit and salinity are two major abiotic stresses that have tremendous effect on crop yield worldwide. Timely identification of these stresses can help limit associated yield loss. Confirmatory detection and identification of water deficit stress can also enable proper irrigation management. Traditionally, unmanned aerial vehicle (UAV)-based imaging and satellite-based imaging, together with visual field observation, are used for diagnostics of such stresses. However, these approaches can only detect salinity and water deficit stress at the symptomatic stage. Raman spectroscopy (RS) is a noninvasive and nondestructive technique that can identify and detect plant biotic and abiotic stress. In this study, we investigated accuracy of Raman-based diagnostics of water deficit and salinity stresses on two greenhouse-grown peanut accessions: tolerant and susceptible to water deficit. Plants were grown for 76 days prior to application of the water deficit and salinity stresses. Water deficit treatments received no irrigation for 5 days, and salinity treatments received 1.0 L of 240-mM salt water per day for the duration of 5-day sampling. Every day after the stress was imposed, plant leaves were collected and immediately analyzed by a hand-held Raman spectrometer. RS and chemometrics could identify control and stressed (either water deficit or salinity) susceptible plants with 95% and 80% accuracy just 1 day after treatment. Water deficit and salinity stressed plants could be differentiated from each other with 87% and 86% accuracy, respectively. In the tolerant accessions at the same timepoint, the identification accuracies were 66%, 65%, 67%, and 69% for control, combined stresses, water deficit, and salinity stresses, respectively. The high selectivity and specificity for presymptomatic identification of abiotic stresses in the susceptible line provide evidence for the potential of Raman-based surveillance in commercial-scale agriculture and digital farming.

5.
F1000Res ; 10: 586, 2021.
Article in English | MEDLINE | ID: mdl-35284061

ABSTRACT

Background: Plant products, including seeds are an important source of vitamins, minerals, proteins, and energy. This study aimed to assess parasitic contaminations in roasted groundnuts, nabag, and tasali (watermelon seeds) sold by street vendors in Khartoum State, Sudan. Methods: The frequency of parasitic contaminations among all crop products was detected by washing the plants with saline, and then conducting an examination using a formal ether concentration technique (FECT), followed by a saturated sugar floatation technique. Results: The detected parasites belonged to two species: Entamoeba histolytica (33.3%) and Giardia lamblia (15.6%). No helminthic parasites were detected. Mixed contamination of the mentioned parasites was also observed (11.1%). The most contaminated crop was nabag, followed by groundnut, and finally tasali. Conclusion: No relation was established between the positivity of samples for parasites and crop type, Khartoum State city, or  seller sex. FECT was more sensitive than the saturated sugar floatation technique as a detection method.


Subject(s)
Citrullus , Intestinal Diseases, Parasitic , Parasites , Animals , Cross-Sectional Studies , Intestinal Diseases, Parasitic/parasitology , Seeds , Sudan/epidemiology , Sugars
6.
Clin Nutr ; 40(4): 1699-1710, 2021 04.
Article in English | MEDLINE | ID: mdl-32980186

ABSTRACT

INTRODUCTION: l-arginine supplementation may improve vascular endothelial function. As tree nuts and groundnuts are a source of the amino acid l-arginine, we performed a meta-analysis of human randomized controlled trials (RCTs) to compare effects of tree nut and groundnut consumption with those of l-arginine supplementation on fasting and postprandial endothelial function as assessed by flow-mediated vasodilation of the brachial artery (FMD). METHODS: Summary estimates of weighted mean differences (WMDs) in FMD and 95% confidence intervals (CIs) were calculated using random-effect meta-analyses. RESULTS: A total of thirteen RCTs focusing on tree nut and groundnut consumption and nineteen RCTs investigating effects of l-arginine supplementation were included. Longer-term consumption of tree nuts and groundnuts increased fasting FMD by 1.09 %-point (PP) (95% CI: 0.49, 1.69, P < 0.001; I2: 76.7%, P < 0.001), while l-arginine supplementation (daily range: 3-21 g) increased fasting FMD by 0.53 PP (95% CI: 0.12, 0.93; P = 0.012; I2: 91.6%, P < 0.001). Effects between treatments were not statistically different (P = 0.31). Tree nut and groundnut consumption did not affect postprandial FMD responses (1.25 PP, 95% CI: -0.31, 2.81, P = 0.12; I2: 91.4%, P < 0.001), whereas l-arginine supplementation (range: 3-15 g) improved FMD during the postprandial phase by 2.02 PP (95% CI: 0.92, 3.13, P < 0.001; I2: 99.1%, P < 0.001). However, treatment effects did not differ significantly (P = 0.60). Overall, these results derive from high-quality evidence. CONCLUSION: Longer-term consumption of tree nuts and groundnuts, as well as l-arginine supplementation did improve fasting endothelial function, as assessed by FMD. However, the positive effects of tree nuts and groundnuts could not be fully explained by the amount of l-arginine in these nuts. Only l-arginine supplementation did improve postprandial FMD, but effects were not different from those of tree nuts and groundnuts. Future studies should focus on the identifications of the bioactive nutrients in tree nuts and groundnuts and mechanistic pathways behind differences in postprandial and longer-term fasting changes in FMD.


Subject(s)
Arginine/pharmacology , Dietary Supplements , Fasting/physiology , Nuts , Postprandial Period/physiology , Vasodilation/physiology , Diet/methods , Humans , Randomized Controlled Trials as Topic
7.
Fungal Biol ; 124(1): 1-7, 2020 01.
Article in English | MEDLINE | ID: mdl-31892372

ABSTRACT

Aspergillus flavus is the main xerophylic species colonising stored peanuts resulting in contamination with aflatoxins (AFs) and cyclopiazonic acid (CPA). This study evaluated the relationship between storage of shelled peanuts under interacting abiotic conditions on (a) temporal respiration (R) and cumulative CO2 production, (b) dry matter losses (DMLs) and (c) aflatoxin B1 (AFB1) and CPA accumulation. Both naturally contaminated peanuts and those inoculated with A. flavus were stored for 7-days under different water activities (aw; 0.77-0.95) and temperatures (20-35°C). There was an increase in the temporal CO2 production rates in wetter and warmer conditions, with the highest respiration at 0.95 aw + A. flavus inoculum at 30°C (2474 mg CO2kg-1h-1). The DMLs were modelled to produce contour maps of the environmental conditions resulting in maximum/minimum losses. Maximum mycotoxin contamination was always at 0.95 aw although optimal temperatures were 25-30°C for AFs and 30-35°C for CPA. These results showed a correlation between CO2 production and mycotoxin accumulation. They also provide valuable information for the creation of a database focused on the development of a post-harvest decision support system to determine the relative risks of contamination with these mycotoxins in stored shelled peanuts.


Subject(s)
Arachis/microbiology , Aspergillus flavus/growth & development , Aspergillus flavus/metabolism , Carbon Dioxide/metabolism , Food Storage , Mycotoxins/analysis , Aflatoxin B1/analysis , Aflatoxin B1/biosynthesis , Food Microbiology , Indoles/analysis , Indoles/metabolism , Mycotoxins/biosynthesis , Temperature , Water
8.
Food Res Int ; 120: 1-11, 2019 06.
Article in English | MEDLINE | ID: mdl-31000218

ABSTRACT

Particular storage conditions are described to promote the development of the hard-to-cook (HTC) phenomenon for most legumes. However, it is not clearly established whether the HTC phenomenon influences starch digestion kinetics. Therefore, this study explored how the HTC phenomenon influences in vitro starch digestion of Bambara groundnuts, taking into account three distinct HTC levels. Stored Bambara groundnuts required prolonged cooking times. Increasing storage time led to a decrease in the rate constant of texture degradation, signifying the development of the HTC phenomenon. For cooking times of 60 min and 120 min, high HTC level samples exhibited higher rate constants and extents of starch digestion compared to the fresh sample. The higher rate of digestion was attributed to the high hardness that resulted in greater cell rupture and faster access of amylase to starch. Adapting cooking times of Bambara groundnuts with distinct HTC levels to obtain equivalent hardness values and microstructures resulted in comparable starch digestion kinetics. Spectrophotometric analysis overestimated the amount of digested starch, in contrast to the more accurate HPLC analysis, which further provided more insight by quantifying multiple digestion products. This work demonstrates that it is the hardness and interlinked pattern of cell failure (microstructure) that determines starch digestion of Bambara groundnuts with distinct HTC levels.


Subject(s)
Cooking , Food Storage , Hardness , Phaseolus , Seeds , Starch/metabolism , Digestion , Humans , Seeds/cytology
9.
Article in English | WPRIM (Western Pacific) | ID: wpr-780946

ABSTRACT

Aims@#Groundnut is an important food crop and is susceptible to contamination by Aspergillus. The present study was conducted to identify Aspergillus spp. from groundnuts as well as to detect mycotoxin production by toxigenic species. @*Methodology and results@#Molecular identification using ITS region, β-tubulin and calmodulin genes identified six species, A. niger, A. tubingensis, A. flavus, A. aculeatus, A. sydowii and A. fumigatus. Phylogenetic tree of combined sequences showed the isolates from the same species were grouped with reference strains in the same clade, thus the species identity was confirmed. Detection of mycotoxin biosynthesis genes can give an indication of mycotoxin production. Two ochratoxin A genes, PKS15KS and PKS15C-MeT were detected in seven A. niger isolates but none of the isolates produced ochratoxin A when quantification was conducted using Ultra-High Performance Liquid Chromatography. Two aflatoxin B1 biosynthesis genes, Nor-1 (norsolorinic acid) and Ver-1 (Versicolorin) genes were detected in A. flavus but only KDH7 and KL27b isolates produced aflatoxin B1 with concentrations of 1.0 μg/g and 1.1 μg/g, respectively. @*Conclusion, significance and impact of study@#Various species of Aspergillus found on groundnuts may lead to potential mycotoxin contamination as toxigenic species were also recovered. The occurrence of Aspergillus spp. can reduce the quality of the legumes as well as reducing their shelf life.

10.
Food Res Int ; 112: 160-168, 2018 10.
Article in English | MEDLINE | ID: mdl-30131123

ABSTRACT

Bambara groundnut is one of the under-utilized African legume crops, valued for its nutritional and health benefits, and for which ongoing studies will help to distinguish its many landraces and select the promising one for breeding programs. To describe the polar metabolome of the seed from 21 Bambara groundnut landraces, untargeted metabolomics approach using UPLC-qTOF-MS (Ultra performance liquid chromatography-Quadrupole time of flight mass spectrometry) was performed. Metabolites belonging to varied compound classes were detected and identified. The total phenolic, flavonoid and anthocyanin contents varied from 0.75 to 17.71 mg GAE.g-1, 0.01 to 2.51 mg QUE.g-1 and 0.03 to 1.31 mg CYE.g-1, respectively. Unsupervised statistics highlighted differences in the metabolome of different landraces. Principal component analysis revealed that caffeic and catechin conjugates are the most decisive marker compounds discriminating the landraces. This study provides the most complete map of metabolites in Bambara groundnut seeds and demonstrates that UPLC-qTOF-MS coupled with chemometric is an excellent tool for differentiation between landraces. These findings highlight the potential of Bambara groundnuts as an economic source of natural antioxidants for human consumption and food industries, and therefore open horizons to the industrial use of Bambara groundnut flours in the development of functional food and feed products.


Subject(s)
Antioxidants/metabolism , Chromatography, High Pressure Liquid , Metabolomics/methods , Phytochemicals/metabolism , Seeds/metabolism , Spectrometry, Mass, Electrospray Ionization , Vigna/metabolism , Anthocyanins/metabolism , Flavonoids/metabolism , Phenols/metabolism , Seeds/classification , Vigna/classification
11.
Mycotoxin Res ; 34(3): 195-204, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29679369

ABSTRACT

Aflatoxin-lysine (AFB1-lys) adduct levels in blood samples collected from 230 individuals living in three districts of Malawi (Kasungu, Mchinji, and Nkhotakota) and aflatoxin B1 (AFB1) levels in groundnut and maize samples collected from their respective homesteads were determined using indirect competitive enzyme-linked immunosorbent assay (IC-ELISA) methods. AFB1-lys adducts were detected in 67% of blood samples, with a mean concentration of 20.5 ± 23.4 pg/mg of albumin. AFB1 was detected in 91% of groundnut samples and in 70% of maize samples, with mean AFB1 levels of 52.4 and 16.3 µg/kg, respectively. All participants of this study reported consuming maize on a daily basis and consuming groundnuts regularly (mean consumption frequency per week: 3.2 ± 1.7). According to regression analysis, a frequency of groundnut consumption of more than four times per week, being female, and being a farmer were significant (p < 0.05) contributors to elevated AFB1-lys adduct levels in the blood. This is the first report on AFB1-lys adducts in blood samples of residents in Malawi. The results reinforce the urgent need for interventions, aiming at a reduction of aflatoxin exposure of the population.


Subject(s)
Aflatoxin B1/analysis , Aflatoxins/analysis , Albumins/analysis , Arachis/chemistry , Food Contamination/analysis , Serum/chemistry , Zea mays/chemistry , Adolescent , Adult , Enzyme-Linked Immunosorbent Assay , Female , Healthy Volunteers , Humans , Malawi , Male , Middle Aged , Rural Population , Young Adult
12.
Toxins (Basel) ; 10(4)2018 03 23.
Article in English | MEDLINE | ID: mdl-29570687

ABSTRACT

At the interface between agriculture and nutrition, the aflatoxin contamination of food and feed touches on agriculture, health, and trade. For more than three decades now, the problem of aflatoxin has been researched in Africa. The interest of development cooperation for aflatoxin and the support to aflatoxin mitigation projects has its ups and downs. The academic world and the development world still seem to operate in different spheres and a collaboration is still challenging due to the complexity of the contamination sources at pre-harvest and post-harvest levels. There is a growing call by research funders and development actors for the impact of solutions at a scale. The solutions to mitigate aflatoxin contamination require new ways of working together. A more prominent role is to be played by social scientists. The role of social scientists in scaling-up the impact of aflatoxin research in Africa and the proposed mitigation solutions is to ensure that awareness, advantage, affordability, and access are systematically assessed. Aflatoxin-reduced staple foods and feed would be an agricultural result with a considerable health and food safety impact.


Subject(s)
Aflatoxins , Food Contamination , Aflatoxins/analysis , Africa , Biological Control Agents , Diet , Food Contamination/analysis , Food Contamination/economics , Food Contamination/prevention & control , Health Knowledge, Attitudes, Practice , Humans , Research , Social Sciences
13.
Int J Food Microbiol ; 261: 49-56, 2017 Nov 16.
Article in English | MEDLINE | ID: mdl-28915412

ABSTRACT

Aflatoxins are cancer-causing, immuno-suppressive mycotoxins that frequently contaminate important staples in Zambia including maize and groundnut. Several species within Aspergillus section Flavi have been implicated as causal agents of aflatoxin contamination in Africa. However, Aspergillus populations associated with aflatoxin contamination in Zambia have not been adequately detailed. Most of Zambia's arable land is non-cultivated and Aspergillus communities in crops may originate in non-cultivated soil. However, relationships between Aspergillus populations on crops and those resident in non-cultivated soils have not been explored. Because characterization of similar fungal populations outside of Zambia have resulted in strategies to prevent aflatoxins, the current study sought to improve understanding of fungal communities in cultivated and non-cultivated soils and in crops. Crops (n=412) and soils from cultivated (n=160) and non-cultivated land (n=60) were assayed for Aspergillus section Flavi from 2012 to 2016. The L-strain morphotype of Aspergillus flavus and A. parasiticus were dominant on maize and groundnut (60% and 42% of Aspergillus section Flavi, respectively). Incidences of A. flavus L-morphotype were negatively correlated with aflatoxin in groundnut (log y=2.4990935-0.09966x, R2=0.79, P=0.001) but not in maize. Incidences of A. parasiticus partially explained groundnut aflatoxin concentrations in all agroecologies and maize aflatoxin in agroecology III (log y=0.1956034+0.510379x, R2=0.57, P<0.001) supporting A. parasiticus as the dominant etiologic agent of aflatoxin contamination in Zambia. Communities in both non-cultivated and cultivated soils were dominated by A. parasiticus (69% and 58%, respectively). Aspergillus parasiticus from cultivated and non-cultivated land produced statistically similar concentrations of aflatoxins. Aflatoxin-producers causing contamination of crops in Zambia may be native and, originate from non-cultivated areas, and not be introduced with non-native crops such as maize and groundnut. Non-cultivated land may be an important reservoir from which aflatoxin-producers are repeatedly introduced to cultivated areas. The potential of atoxigenic members of the A. flavus-L morphotype for management of aflatoxin in Zambia is also suggested. Characterization of the causal agents of aflatoxin contamination in agroecologies across Zambia gives support for modifying fungal community structure to reduce the aflatoxin-producing potential.


Subject(s)
Aflatoxins/analysis , Arachis/microbiology , Aspergillus/metabolism , Food Contamination/analysis , Zea mays/microbiology , Aspergillus/isolation & purification , Crops, Agricultural/microbiology , Zambia , Zea mays/chemistry
14.
J Stored Prod Res ; 72: 54-58, 2017 May.
Article in English | MEDLINE | ID: mdl-28659647

ABSTRACT

We conducted an experiment in Niger to evaluate the performance of hermetic triple layer (Purdue Improved Crop Storage- PICS) bags for the preservation of shelled and unshelled groundnut Arachis hypogaea L. Naturally-infested groundnut was stored in PICS bags and woven bags for 6.7 months. After storage, the average oxygen level in the PICS bags fell from 21% to 18% (v/v) and 21%-15% (v/v) for unshelled and shelled groundnut, respectively. Identified pests present in the stored groundnuts were Tribolium castaneum (Herbst), Corcyra cephalonica (Stainton) and Cryptolestes ferrugineus (Stephens). After 6.7 months of storage, in the woven bag, there was a large increase in the pest population accompanied by a weight loss of 8.2% for unshelled groundnuts and 28.7% for shelled groundnut. In PICS bags for both shelled and unshelled groundnuts, by contrast, the density of insect pests did not increase, there was no weight loss, and the germination rate was the same compared to that recorded at the beginning of the experiment. Storing shelled groundnuts in PICS bags is the most cost-effective way as it increases the quantity of grain stored.

15.
J Food Prot ; 80(1): 44-49, 2017 01.
Article in English | MEDLINE | ID: mdl-28198655

ABSTRACT

Aflatoxin, a human liver carcinogen, frequently contaminates groundnuts, maize, rice, and other grains, especially in Africa. The aim of this study was to evaluate the effectiveness of an educational intervention that involved training rural Gambian women on how to identify and remove moldy groundnuts to reduce aflatoxin B1 (AFB1) contamination. In total, 25 women, recruited from the West Kiang region of The Gambia, were trained on how to recognize and remove moldy groundnuts. Market-purchased groundnuts were hand sorted by the women. Groundnuts were sampled at baseline (n =5), after hand sorting ("clean," n =25 and "moldy," n =25), and after roasting (n =5). All samples were analyzed for AFB1 by enzyme-linked immunosorbent assay. A reduction of 42.9% was achieved based on the median AFB1 levels at baseline and after hand sorting (clean groundnuts), whereas an alternative estimate, based on the total AFB1 in moldy and clean groundnuts, indicated a reduction of 96.7%, with a loss of only 2% of the groundnuts. By roasting the already clean sorted groundnuts, the AFB1 reduction achieved (based on median levels) was 39.3%. This educational intervention on how to identify and remove moldy groundnuts was simple and effective in reducing AFB1 contamination.


Subject(s)
Aflatoxin B1 , Aflatoxins , Arachis , Enzyme-Linked Immunosorbent Assay , Female , Gambia , Humans
16.
Food Addit Contam Part B Surveill ; 10(1): 21-26, 2017 Mar.
Article in English | MEDLINE | ID: mdl-27700622

ABSTRACT

Aflatoxins, mainly produced by Aspergillus flavus and Aspergillus parasiticus, are highly toxic and may lead to health problems such as liver cancer. Exposure to aflatoxins may result from ingestion of contaminated foods. Levels of AFB1, AFB2, AFG1 and AFG2 in samples of groundnuts (Arachis hypogaea), beans (Phaseolus vulgaris), cowpeas (Vigna unguiculata) and bambara nuts (Vigna subterranean) grown by smallholder farmers in Shamva and Makoni districts, Zimbabwe, were determined at harvesting, using high performance liquid chromatography after immunoaffinity clean-up. Aflatoxins were detected in 12.5% of groundnut samples with concentrations ranging up to 175.9 µg/kg. Aflatoxins were present in 4.3% of the cowpea samples with concentrations ranging from 1.4 to 103.4 µg/kg. Due to alarming levels of aflatoxins detected in legumes versus maximum permissible levels, there is a need to assist smallholder farmers to develop harvest control strategies to reduce contamination of aflatoxins in legumes.


Subject(s)
Aflatoxins/analysis , Agriculture/methods , Fabaceae , Food Contamination/analysis , Food Microbiology , Food Supply/standards , Seeds/chemistry , Aflatoxins/adverse effects , Arachis , Aspergillus , Chromatography, High Pressure Liquid , Diet , Humans , Phaseolus , Quality Control , Vigna , Zimbabwe
17.
J Agric Food Chem ; 64(3): 579-84, 2016 Jan 27.
Article in English | MEDLINE | ID: mdl-26672388

ABSTRACT

Two new stilbene derivatives have been isolated from peanut seeds challenged by an Aspergillus flavus strain, along with chiricanine B, which has not been previously reported from peanuts, as well as a stilbenoid reported previously only as a synthetic product. The structures of these new putative phytoalexins were determined by analysis of (1)H and (13)C NMR, HRESIMS, MS(n), and UV data. The new stilbenoids were named arahypin-13 (21), arahypin-14 (22), and arahypin-15 (23). Together with other known bioactive peanut stilbenoids that were also produced in the challenged seeds, these new compounds may play a defensive role against invasive fungi.


Subject(s)
Arachis/microbiology , Seeds/immunology , Sesquiterpenes/chemistry , Sesquiterpenes/immunology , Stilbenes/chemistry , Stilbenes/immunology , Arachis/chemistry , Arachis/immunology , Molecular Structure , Seeds/chemistry , Seeds/microbiology , Phytoalexins
18.
J Food Prot ; 79(12): 2160-2166, 2016 12.
Article in English | MEDLINE | ID: mdl-28221960

ABSTRACT

Experiments were conducted to assess the influence of storage practices on mycotoxin incidences in stored maize and groundnuts in Kilosa District, Eastern Central Tanzania. Factorial experiments were used to test the effects of processing, storage conditions, and protectants at 3-month intervals for 12 weeks. Temperature and relative humidity data were recorded by using data loggers. The differences among the treatment means were compared using Tukey's honestly significant difference test at 5% probability level. The log-linear model was used to determine the influence of weather on mycotoxin. Dried neem ( Azadirachta indica ) leaves significantly reduced fumonisin B1 (FB1) in stored maize. Levels of FB1 were significantly higher in maize heaped on the floor than in the other tested storage methods (P < 0.001). Similarly, aflatoxin levels were significantly higher in groundnuts stored in nylon bags than in the other tested methods (P < 0.001). The high concentration of mycotoxins at the study villages suggests that storage practices and weather conditions play major roles in mycotoxin production.


Subject(s)
Food Contamination , Zea mays , Fumonisins , Mycotoxins , Tanzania
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