Measuring and mitigating the risk of mycotoxins in maize and dairy products for poor consumers in Kenya (MyDairy)

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The role of mycotoxin contamination in nutrition: The aflatoxin story
(Book Chapter, 2016-10-17) Ayalew, Amare; Hoffmann, Vivian; Lindahl, Johanna; Ezekiel, Chibundu N.
Over the past decade, there has been increasing recognition that the quantity of food alone guarantees neither food security nor adequate nutrition as measured by metrics such as hunger, malnutrition, and stunting. Increasingly, policy and decision makers understand the need to include nutritional aspects into improvements of food systems. However, not as fully recognized is that unsafe, contaminated foods thwart these efforts and maintain an unacceptable status quo in food insecurity, poverty, and a range of health-related problems. All of this makes sustainable development more challenging. In 2010, foodborne hazards caused 600 million illnesses and 420,000 deaths across the world, with 40 percent of this disease burden occurring among children under five years of age (Global Panel on Agriculture and Food Systems for Nutrition 2016). Yet food safety has become an important precondition for access to global food markets and, increasingly, for high-value domestic markets in developing countries.
AFM1 secretion and efficacy of Novasil™ clay in Kenyan dairy cows
(Journal Article, 2022-03-28) Kuboka, Maureen; Njue, L.; Mutua, Florence K.; Grace, Delia; Lindahl, Johanna F.
The occurrence of aflatoxin M1 (AFM1) in milk has been widely reported in Kenya, with levels frequently exceeding national and international thresholds. Exposure to aflatoxin increases the risk of hepatic cancers and can also have other negative health impacts in children such as growth impairment and immunosuppression. Anti-mycotoxin agents (AMAs) included in contaminated feeds can greatly reduce the amount of AFM1 released in milk. A 45-day trial was designed to assess secretion of AFM1 in milk from individual cows fed commercial Kenyan dairy feed, as well as the efficacy of Novasil™ Plus in reducing the levels. A four-by-four Latin square cross-over design was used for the experiment. Four cows were fed on naturally contaminated with AFB1 feed, with levels ranging from 19 to 47 µg/kg, and either no binder or inclusion of binder at the rate of 0.6 or 1.2%. Milk samples were collected each day and analyzed for AFM1. The results showed that AFM1 levels in the milk varied between the cows, even when fed similar levels of contaminated feed. On average, inclusion of 0.6% binder into the diet resulted in 34% decline in milk AFM1 levels, while 1.2% binder dose resulted in a decline of 45%. Significant reduction in AFM1 secretion was observed in all experimental units (p < 0.005), though only minimal reduction was recorded in one of the units (Cow 4) compared to the other three. This trial shows novel data on aflatoxin exposure and excretion in Kenyan dairy cows in a field setting where AFB1 level is uncontrolled. We demonstrate significant reduction in AFM1 secretion in milk using AMA, though AFM1 levels were still above the recommended EC standard of 50 ŋg/kg. This study suggests that AMAs alone cannot be relied on to reduce AFM1 in milk to safe levels. Training and good feeding practices are recommended in addition to use of AMAs.
Effectiveness of training and use of Novasil binder in mitigating aflatoxins in cow milk produced in smallholder farms in urban and periurban areas of Kenya
(Journal Article, 2021-04-15) Anyango, G.; Kagera, I.; Mutua, Florence K.; Kahenya, P.; Kyallo, F.; Andang’o, P.; Grace, Delia; Lindahl, Johanna F.
Aflatoxins, which commonly contaminate animal feeds and human food, present a major public health challenge in sub-Saharan Africa. After ingestion by cows, aflatoxin B1 is metabolized to aflatoxin M1 (AFM1), some of which is excreted in milk. This study involved smallholder dairy farms in urban and periurban areas of Nairobi and Kisumu, Kenya. The objective was to determine the effectiveness of training and providing farmers with aflatoxin binder (NovaSil®) on AFM1 contamination in raw milk. A baseline survey was undertaken and 30 farmers whose milk had AFM1 levels above 20 ppt were randomly selected for inclusion in the study. Of these, 20 farmers were part of the intervention, and were given training on the usage of the NovaSil® binder, while 10 served as a control group. All farmers were visited biweekly for three months for interviews and milk samples were collected to measure the AFM1 levels. The AFM1 levels were quantified by enzyme linked immunosorbent assay. The NovaSil® binder significantly reduced AFM1 concentrations in the raw milk produced by the farmers in the intervention group over the duration of the study (p < 0.01). The control farms were more likely to have milk with AFM1 levels exceeding the regulatory limit of 50 ppt compared to the intervention farms (p < 0.001) (odds ratio = 6.5). The farmers in the intervention group perceived that there was an improvement in milk yield, and in cow health and appetite. These farmers also felt that the milk they sold, as well as the one they used at home, was safer. In conclusion, the use of binders by dairy farmers can be effective in reducing AFM1 in milk. Further research is needed to understand their effectiveness, especially when used in smallholder settings.
Aflatoxins: A food safety hazard in Kenyan dairy chains – prevalence, risks and assessment of a biocontrol solution
(Thesis, 2020-12-16) Ahlberg, S.
Aflatoxins continue to be a food safety problem globally, especially in developing regions. Prevalent food contaminating aflatoxins are B1 (AFB1) and M1 (AFM1). These are human carcinogens and have potentially severe health impacts. Almost all (99.5 %) milk samples from Nairobi were contaminated with AFM1, highlighting the urgent need to create functional solutions to improve food safety. Based on the aflatoxin levels and milk consumption, risks were calculated: cancer risk caused by AFM1 was lower among consumers purchasing from formal markets (0.003 cases per 100,000) than for low-income consumers (0.006 cases per 100,000) purchasing from informal markets. Overall cancer risk (0.004 cases per 100,000) from AFM1 alone was low. Because of AFM1 in milk, 2.1 % of children below three years in middle-income families, and 2.4 % in low-income families, could be stunted. Overall, 2.7 % of children could hypothetically be stunted due to AFM1 exposure from milk. Based on these results AFM1 levels found in milk could contribute to an average of -0.340 height for age z-score reduction in growth. The exposure to AFM1 from milk is 46 ng/day on average, but children bear higher exposure of 3.5 ng/kg bodyweight (bw)/day compared with adults, at 0.8 ng/kg bw/day. Aflatoxins are produced by Aspergillus flavus fungus, which is prevalent in soils. Certain strains of lactic acid bacteria (LAB) have been reported inhibiting fungal growth. 171 LAB strains were tested against aflatoxin producing A. flavus fungi. The three LAB strains showing the highest antifungal activity were identified as Lactobacillus plantarum. None of the strains was able to completely inhibit fungal growth under conditions favorable for fungi and suboptimal for LAB. The three indigenous LAB Lactobacillus strains and one Lactococcus strains were tested for their AFM1 binding abilities in different conditions and after different treatments along with two reference Lactobacillus strains. The binding of AFM1 by LAB strains varied between 11 to 100 % in the biocontrol solution analysis, being approximately at the level of 40 % throughout the analysis sets. A significant amount of effort and resources have been invested in an attempt to control aflatoxins. However, these efforts have not substantially decreased the prevalence nor dietary exposure to aflatoxins in developing countries. The growth reduction of aflatoxin producing fungi with LAB could be one potential option, but there are still major issues to solve prior to any practical applications. A different approach to control aflatoxins suggesting the usage of binding agents in foods and lactic acid bacteria (LAB) have been studied extensively for this purpose. However, when assessing the results comprehensively and reviewing the practicality and ethics of use, risks are evident, and concerns arise. In conclusion, there are too many issues with using LAB for aflatoxin binding for it to be safely promoted. Arguably, using binders in human food might even worsen food safety in the longer term. A more comprehensive food safety approach has to be taken to solve this ongoing crisis.
Preliminary study on the relationship between aflatoxin-bovine serum albumin adducts in blood and aflatoxin M1 levels in milk of dairy cows
(Journal Article, 2020-05) Saltzmann, J.; Xu, Y.; Gong, Y.Y.; Kersten, S.; Danicke, S.; Routledge, M.N.; Lindahl, Johanna F.
The aflatoxin (AF) albumin adduct is often used as a biomarker for aflatoxin exposure in humans. An ELISA method previously used for aflatoxin serum albumin in human blood was used to analyse bovine serum samples (n = 22) collected from dairy cattle during an aflatoxin mitigation study in Kenya. Albumin adduct data were compared with aflatoxin M1 (AFM1) levels in corresponding milk samples from these cows. The concentration ranged from < LOD to 487.9 pg/mL for AFM1 and < LOD and 96.3 pg/mg for aflatoxin-albumin. This study indicates that aflatoxin-albumin adducts could be used as a measure of chronic aflatoxin exposure in dairy cattle.
Aflatoxin exposure from milk in rural Kenya and the contribution to the risk of liver cancer
(Journal Article, 2019-08-10) Sirma, A.J.; Makita, K.; Grace, Delia; Senerwa, D.; Lindahl, Johanna F.
Milk is an important commodity in Kenya; the country has the largest dairy herd and highest per capita milk consumption in East Africa. As such, hazards in milk are of concern. Aflatoxin M1 (AFM1) is a toxic metabolite of aflatoxin B1 (AFB1) excreted in milk by lactating animals after ingesting AFB1-contaminated feeds. This metabolite is injurious to human health, but there is little information on the risk to human health posed by AFM1 in milk in rural Kenya. To fill this gap, a quantitative risk assessment (QRA) applying probabilistic statistical tools to quantify risks was conducted. This assessed the risk of liver cancer posed by AFM1 in milk, assuming 10-fold lower carcinogenicity than AFB1. Data from four agro–ecological zones in Kenya (semi-arid, temperate, sub-humid and humid) were used. We estimated that people were exposed to between 0.3 and 1 ng AFM1 per kg body weight per day through the consumption of milk. The annual incidence rates of cancer attributed to the consumption of AFM1 in milk were 3.5 × 10−3 (95% CI: 3 × 10−3–3.9 × 10−3), 2.9 × 10−3 (95% CI: 2.5 × 10−3–3.3 × 10−3), 1.4 × 10−3 (95% CI: 1.2 × 10−3–1.5 × 10−3) and 2.7 × 10−3 (95% CI: 2.3 × 10−3–3 × 10−3) cancers per 100,000 in adult females, adult males, children 6–18 years old, and in children less than five years old, respectively. Our results show that aflatoxin exposure from milk contributes relatively little to the incidence of liver cancer. Nonetheless, risk managers should take action based on cumulative exposure from all sources of aflatoxins.
Occurrence of aflatoxin M1 in raw milk traded in peri-urban Nairobi, and the effect of boiling and fermentation
(Journal Article, 2019-01-01) Kuboka, M.M.; Imungi, J.K.; Njue, L.; Mutua, Florence K.; Grace, Delia; Lindahl, Johanna F.
Background: Dairy production in Kenya is important and dominated by small-holder farmers who market their produce through small-scale traders in the informal sector. Method: This study aimed to determine the prevalence of aflatoxin (AFM1) in informally marketed milk in peri-urban Nairobi, Kenya, and to assess knowledge of milk traders on aflatoxins using questionnaires. A total of 96 samples were analyzed for AFM1 using enzyme-linked immunosorbent assay. In addition, boiling and fermentation experiments were carried out in the laboratory. Results: All samples had AFM1 above the limit of detection (5 ng/kg) (mean of 290.3 ± 663.4 ng/kg). Two-thirds of the samples had AFM1 levels above 50 ng/kg and 7.5% of the samples exceeded 500 ng/kg. Most of the traders had low (69.8%) or medium (30.2%) knowledge. Educated (p = 0.01) and female traders (p= 0.04) were more knowledgeable. Experimentally, fermenting milk to lala (a traditional fermented drink) and yogurt significantly reduced AFM1 levels (p< 0.01) (71.8% reduction in lala after incubation at room temperature for 15 h, and 73.6% reduction in yogurt after incubation at 45ºC for 4h). Boiling had no effect. Conclusion: The study concluded that the prevalence of raw milk with AFM1 was high, while knowledge was low. Fermentation reduced the AFM1 levels.
Availability and use of mycotoxin binders in selected urban and peri-urban areas of Kenya
(Journal Article, 2019-04) Mutua, Florence K.; Lindahl, Johanna F.; Grace, Delia
Aflatoxins are carcinogenic, toxic and immunosuppressive substances produced by some species of the fungal genus, Aspergillus. Consumption of aflatoxins can have serious health effects. Widespread in the tropical and sub-tropical world, aflatoxin B1 (AFB1) is found in many staple foods and feeds; after ingestion it is metabolized to aflatoxin M1 (AFM1), which transfers to milk. One option for reducing aflatoxin concentration in cow milk is addition of mycotoxin binders to animal feeds, but little is known about this practice in the smallholder dairy systems in developing countries. We undertook a study to investigate the availability and use of mycotoxin binders in selected urban and peri-urban areas of Kenya. Data were collected using key informant interviews with government officials and one-to-one questionnaire-guided interviews with agrovet outlets (shops that sell animal health products (such as antibiotics) and crop inputs (such as fertilizers) and feed processors. Nine different mycotoxin binder types were reported. They were sold by 8% (4/49) of agrovets and 33% (3/9) of feed processors. The binders were purchased by farmers formulating their own feeds and by feed processors. Our review of regulations found that incorporating binders into animal feeds is not mandatory and there are no specific standards governing their use in Kenya. Feed processors are expected to respect the maximum allowable limit of 5 μg/kg for AFB1 in complete feeds. Gaps in the local feed supplies that may potentially lead to increased risks of aflatoxin exposure through milk are discussed. This study provides key data on the availability and local use of mycotoxin binders, which were previously lacking. However, there is a need for continued research on their effectiveness in the local smallholder context, in order to promote their appropriate use.
A survey of aflatoxin M1 contamination in raw milk produced in urban and peri-urban areas of Kisumu County, Kenya
(Journal Article, 2018-01) Anyango, G.; Mutua, Florence K.; Kagera, I.; Andang'o, P.; Grace, Delia; Lindahl, Johanna F.
Background: Food safety is of increasing global concern, and a OneHealth issue requiring attention of many disciplines. Aflatoxins are toxins produced by fungi and found in foods and feeds, and exposure causes negative health effects in humans and animals. When lactating animals consume aflatoxin B1, the metabolite (AFM1) is transferred to milk. Methods: A cross-sectional study was designed to determine characteristics of smallholder dairy farming in urban and peri-urban areas of Kisumu and quantify AFM1 in milk. Data was collected from 97 randomly selected dairy farms on farming practices, milk production, and awareness about aflatoxins. Collected milk samples were analyzed using enzyme-linked immunosorbent assay for AFM1. Results: Average milk produced was 13 liters per day per household and mainly used for household consumption and sold to neighbours. Farmers mainly fed cows on forage and concentrates (62.9%). Levels of AFM1 ranged from below the detection limit to 151 ppt, with a mean of 29.67 ppt; 26.4% exceeding the EU limit. Concentrate feeding was associated with higher AFM1 levels (p = 0.002); with farms feeding concentrates more likely to have levels exceeding 50 ppt (OR = 10.1). Conclusion: In conclusion, milk produced by small holder dairy farmers in Kisumu County frequently is contaminated with AFM1, implying health risks for human and animals.
Status of aflatoxin contamination in cow milk produced in smallholder dairy farms in urban and peri-urban areas of Nairobi County: A case study of Kasarani sub county, Kenya
(Journal Article, 2019-01-01) Kagera, Irene; Kahenya, Peter; Mutua, Florence K.; Anyango, Gladys; Kyallo, Florence; Grace, Delia; Lindahl, Johanna F.
Introduction: Milk consumption in Kenya supersedes other countries in East Africa. However, milk contamination with aflatoxin M1 (AFM1) is common, but the magnitude of this exposure and the health risks are poorly understood and need to be monitored routinely. This study aimed at assessing the awareness, knowledge and practices of urban and peri-urban farmers about aflatoxins and determining the levels of aflatoxin contamination in on-farm milk in a selected area within Nairobi County. Materials and methods: A cross-sectional study was undertaken to assess aflatoxin contamination levels of milk in Kasarani sub-county. A total of 84 milk samples were collected from small-holder dairy farms and analyzed for AFM1 using Enzyme-Linked Immunosorbent Assay (ELISA). Results and Discussion: Ninety nine percent of the samples (83/84) analysed were contaminated with AFM1. The mean aflatoxin level was 84 ng/kg with 64% of the samples exceeding the EU legal limit of 50 ng/kg. Whereas 80% of the farmers were aware of aflatoxin, there was no correlation between farmers’ knowledge and gender with AFM1 prevalence. Conclusion: This study concludes that AFM1 is a frequent contaminant in milk and there is need to enhance farmers awareness on mitigation.
A risk assessment of aflatoxin M1 exposure in low and mid-income dairy consumers in Kenya
(Journal Article, 2018-08-29) Ahlberg, Sara H.; Grace, Delia; Kiarie, G.; Lindahl, Johanna F.
Aflatoxin M1 (AFM1), a human carcinogen, is found in milk products and may have potentially severe health impacts on milk consumers. We assessed the risk of cancer and stunting as a result of AFM1 consumption in Nairobi, Kenya, using worst case assumptions of toxicity and data from previous studies. Almost all (99.5%) milk was contaminated with AFM1. Cancer risk caused by AFM1 was lower among consumers purchasing from formal markets (0.003 cases per 100,000) than for low-income consumers (0.006 cases per 100,000) purchasing from informal markets. Overall cancer risk (0.004 cases per 100,000) from AFM1 alone was low. Stunting is multifactorial, but assuming only AFM1 consumption was the determinant, consumption of milk contaminated with AFM1 levels found in this study could contribute to 2.1% of children below three years in middle-income families, and 2.4% in low-income families, being stunted. Overall, 2.7% of children could hypothetically be stunted due to AFM1 exposure from milk. Based on our results AFM1 levels found in milk could contribute to an average of −0.340 height for age z-score reduction in growth. The exposure to AFM1 from milk is 46 ng/day on average, but children bear higher exposure of 3.5 ng/kg bodyweight (bw)/day compared to adults, at 0.8 ng/kg bw/day. Our paper shows that concern over aflatoxins in milk in Nairobi is disproportionate if only risk of cancer is considered, but that the effect on stunting children might be much more significant from a public health perspective; however, there is still insufficient data on the health effects of AFM1.
The impacts of aflatoxin standards on health and nutrition in sub-Saharan Africa: The case of Kenya
(Journal Article, 2018-09) Sirma, A.J.; Lindahl, Johanna F.; Makita, K.; Senerwa, D.; Mtimet, Nadhem; Kang’ethe, E.K.; Grace, Delia
Human food and animal feed can contain many different hazards, which may be biological, chemical, or physical. In most countries, there are regulations that limit the levels of these hazards permitted in food and feed so as to protect consumers. Optimally, the levels specified in the standards should make the food safe enough for everyone to consume, and often this is done by carrying out a risk assessment, based on scientific evidence of the levels that can be considered safe and the amount of contaminated products consumed. However, for some substances, especially carcinogens, it is difficult to calculate how much is safe to consume and some groups of people, such as small children or pregnant women, may be more sensitive than the population at large. While imposition of standards is motivated by health benefits, standards also have costs. These include the costs of compliance and verification, which translate- into increased costs of purchase and reduction of the products available. In this paper we summarize current standards in sub-Saharan Africa related to aflatoxins, a priority hazard, and discuss their coherence and evidence-base. Next, using our recent research findings, we estimate the health risks of consuming foods contaminated with aflatoxins in Kenya. We also estimate the negative health and economic effects that would arise from strict application of different standards for aflatoxins. We discuss the results in light of health and nutrition goals.
Aflatoxin M1 levels in different marketed milk products in Nairobi, Kenya
(Journal Article, 2018-11) Lindahl, Johanna F.; Kagera, I.N.; Grace, Delia
Milk is an important source of energy and nutrients, especially for children, and in Kenya, milk consumption is higher than other countries in the region. One major concern with milk is the risks of chemical contaminants, and reports of high levels of aflatoxin M1 (AFM1) in milk in Kenya has been causing public health concerns. This study collected marketed milk products every month during 1 year, just as a consumer would purchase them from retailers and traders in a low-income area, and a major supermarket in a middle/high-income area. In total, 291 sampled milk products (raw, pasteurised, UHT milk, yoghurt and lala) were collected and analysed for AFM1 using a commercial ELISA kit. More than 50% of the samples exceeded 50 ng/kg (the level allowed in the EU), but only three samples exceeded 500 ng/kg (the level allowed in the USA). Geometric mean AFM1 level was 61.9 ng/kg in the 135 samples from the low-income area while it was 36.1 ng/kg in the 156 from the higher income area (p < 0.001). The levels varied significantly depending on the time of year, with lowest levels of milk in January. There were also differences between manufacturers and products, with UHT milk having lower levels. There was no difference depending on the price for all dairy products, but when only including milk, higher price was associated with lower levels of AFM1. In conclusion, this study shows that milk purchased by a consumer is likely to contain AFM1 above 50 ng/kg, and that further research is needed to find ways to mitigate AFM1 contamination through working with farmers and milk processors both in the formal and informal sectors.
Report of the Growing with Dairy stakeholder meeting and MoreMilk project launch
(Report, 2018-03) International Livestock Research Institute
Measuring and mitigating the risk of mycotoxins in maize and dairy products for poor consumers in Kenya
(Presentation, 2018-03-09) Lindahl, Johanna F.; Grace, Delia; Joutsjoki, V.; Korhonen, H.; Hoffmann, Vivian
Are aflatoxins a One Health issue? Results and insights from studies on aflatoxins in the East African dairy value chains
(Conference Paper, 2016-08-23) Lindahl, Johanna F.; Senerwa, D.M.; Mwangi, G.; Sirma, A.J.; Atherstone, Christine; Grace, Delia
Aflatoxins are toxic byproducts from some Aspergillus fungi, mainly Aspergillus flavus, colonizing crops before and after harvest, with preference for maize and groundnuts. In large quantities the toxins are mainly hepatotoxic, and can cause death due to liver failure. Chronic low-dose exposure has been shown to cause immunosuppression and reduced growth in animals, and has been associated with stunting in children. Aflatoxin B1 is one of the most potent natural carcinogens known, causing hepatocellular carcinoma. When animals consume aflatoxins they may have clinical symptoms, reduced productivity and performance, but our literature review suggest that there is still knowledge gaps as to how much animals are affected. In addition, aflatoxins are metabolized by the animals, and residues may persist in low levels in meat and eggs, but around 7-10% of what a dairy cow consumed is excreted as the metabolite aflatoxin M1 into the milk. Our research from Kenya show that milk may contain 140 times WHO recommended levels, and feed samples may contain almost 2000 times the legal levels in Kenya. In some of the studied villages, 100% of samples exceeded legal limits. In addition, our study on urban children shows high rates of stunting in low-income areas, and an association with the consumption of aflatoxin M1. Thus, aflatoxins are a problem affecting both humans and animals, where animals do contribute to the risks for humans, but we also discuss around the potential of animals acting as a solution for the problem as well, discussing policies and mitigation methods.
Analysis of antibiotic residues in milk from smallholder farms in Kenya
(Journal Article, 2016-04-15) Ahlberg, Sara H.; Korhonen, H.; Lindfors, E.; Kang'ethe, Erastus K.
The aim of this study was to determine the occurrence of antibiotic residues in Kenyan smallholder farm milk using screening tests, and to identify the antibiotic residue group. A total of 480 milk samples were analyzed. All samples were analyzed with the Delvotest® screening test. A Hundred and fourteen (24%) samples were positive, 71 (15%) unclear and 295 (61%) negative. Sixty-two samples were further tested with the group specific Trisensor test. Twenty four percent (15/62) were positive. This indicated that by estimation, 9% of all the 480 samples have been positive with the Trisensor test and 5% would have contained beta-lactams, 2.5 % sulfonamides and 0.6 % tetracyclines. Samples with a positive Trisensor test results were further analyzed with HPLC but no antibiotics could be identified. Seventy six percent of the Delvotest® positive samples were negative in Trisensor test. Microbiological inhibitor methods are demanding for the sample conditions and were found not to be best suited to the conditions encountered in smallholder farms in Kenya. The results indicate that antibiotic residues are found in milk produced on small scale farms in Kenya and suggest that training is needed on the use of veterinary drugs.
Aflatoxins and animal health: Case studies from Africa
(Presentation, 2016-03-23) Lindahl, Johanna F.; Atherstone, Christine; Grace, Delia
Aspergillus flavus growth inhibition by Lactobacillus strains isolated from traditional fermented Kenyan milk and maize products
(Journal Article, 2017-04) Ahlberg, Sara H.; Joutsjoki, V.; Laurikkala, S.; Varmanen, P.; Korhonen, H.
Certain strains of lactic acid bacteria have been reported to inhibit fungal growth and may so be potential as biocontrol agents. In this study, 171 LAB strains were isolated from traditional fermented Kenyan milk and maize products and tested against aflatoxin-producing A. flavus fungi. The three LAB strains showing highest antifungal activity were identified as Lactobacillus plantarum. None of the strains were able to completely inhibit fungal growth under conditions favorable for fungi and suboptimal for LAB. These conditions probably reduced the growth and metabolic activity of some LAB isolates, as several growth-related aspects like production of antifungal biomolecules and other metabolites contribute to the inhibiting activity. The results suggest that certain LAB strains could be employed in food to control the growth of aflatoxigenic fungi. Further studies to establish the efficacy of the potential LAB strains in fermented products are in progress.
Aflatoxins in East Africa: The importance of getting the full picture
(Journal Article, 2016-07-15) Lindahl, Johanna F.; Grace, Delia; Harvey, Jagger J.W.; Kang'ethe, Erastus K.

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