Mycoflora and occurrence of aflatoxin in dried vegetables in Benin, Mali and Togo, West Africa

Toxicogenic Fungi, Aflatoxins, and Antimicrobial Activities Associated with Some Spices and Herbs from Three Selected Markets in Ho Municipality, Ghana

Spices and herbs are widely used food ingredients that enhance most organoleptic features of prepared foods. They are also used for medicinal and preservative purposes. Spices and herbs are potential carriers of bacteria, yeasts, and molds due to the nature of cultivation, harvest methods, storage conditions, packaging procedures, distribution, sale, and general handling. Although some fungi have been identified to be associated with most spices and herbs elsewhere in the world, little has been done on the presence of fungi in spices and herbs in Ghana. This study sought to identify the toxicogenic fungal profiles, mycotoxins (aflatoxins) present in some herbs, bay leaf (Laurus nobilis) and garden egg leaves (“gboma”) (Solanum macrocarpon), and spices, ginger (Zingiber officinale) and “dawadawa”(Parkia biglobosa), as well as to investigate the antimicrobial properties of the selected herbs and spices. The decimal reduction technique was used to plate onto Dichloran Rose Bengal Chloramphenicol (DRBC) agar media plates for fungal growth. Aflatoxin detection was carried out with high-performance liquid chromatographer connected to a fluorescence detector (HPLC-FLD). Antimicrobial properties were carried out using the agar diffusion method on solidified, freshly prepared Mueller-Hinton agar. A total of 12 species belonging to 7 genera, Aspergillus (niger, flavus, fumigatus, and ochraceus), Fusarium (oxysporum, verticillioides), Mucor (racemosus), Penicillium (digitatum, expansum), Rhizopus (stolonifer), Rhodotorula sp., and Trichoderma harzianum, were identified as fungal contaminants. Fusarium oxysporum was the most predominant species identified. Fresh ginger recorded the greatest number of colony-forming units (3.71 log10 CFU/g) with bay leaves recording the least number of colony counts (2.36 log10 CFU/g). Mycotoxin concentration detected in gboma was $2.06\pm 0.07\mu \text{g}/\text{kg}$ and in dawadawa was $2.13\pm 0.09\mu \text{g}/\text{kg}$ ; however, mycotoxins were not detected in bay leaf and ginger. Ginger exhibited antibacterial activity against all bacteria ranging from $7.0\pm 0.0\text{mm}$ to $12.0\pm 5.66\text{mm}$ zones of inhibition. Ginger, bay leaf, and gboma extracts displayed fair antimicrobial activity against the bacteria investigated. On the other hand, dawadawa generally produced the least resistance against the five bacterial species but exhibited the highest zone of inhibition. All samples were slightly acidic with pH readings ranging from 5.81 to 6.76.

Microbial Contamination and Occurrence of Aflatoxins in Processed Baobab Products in Kenya

Baobab fruit demand has been on the rise in the recent past, and in an attempt to match the demand, farmers and middlemen are forced to harvest immature fruits which are not fully dried. To ensure an acceptable moisture content, baobab fruits are subjected to solar drying, which is a slow process and often carried out in open and unhygienic conditions raising safety concerns. This study was conducted to investigate the microbial and aflatoxin contamination levels in ready-to-eat baobab products from selected formal and informal processors in specific counties of Kenya. Selected processed baobab products were sampled randomly from formal and informal processors and analyzed for the total aerobic count, Enterobacteriaceae, yeast and molds, ergosterol, aflatoxins, moisture, and water activity. The moisture and water activity of baobab pulp and candies from formal processors ranged between 7.73% and 15.06% and 0.532 and 0.740 compared to those from informal processors which ranged from 10.50% to 23.47% and 0.532 to 0.751, respectively. In this study, baobab pulp from formal processors had significantly ( $p=0.0008$ , 0.0006) lower Enterobacteriaceae and yeast and molds loads ( $0.7\pm 0.29$ and $3.1\pm 0.38$ log 10 CFU/g, respectively) than pulp from informal processors ( $3.1\pm 0.70$ and $5.3\pm 0.11$ log 10 CFU/g, respectively). Similarly, the Enterobacteriaceae counts of candies from formal processors (nondetectable) were considerably lower ( $p=0.015$ ) than those from informal processors ( $1.8\pm 0.56$ log 10 CFU/g). The ergosterol content in these baobab product samples ranged between 0.46 and 1.92 mg/100 g while the aflatoxin content ranged between 3.93 and $11.09\times 103\mu \text{g}/\text{kg}$ , respectively. Fungal and aflatoxin contamination was detected in 25% and 5% of pulp from formal and informal processors, respectively, and in 5% of candies from informal processors. Microbial contamination in processed baobab products shows an unhygienic processing environment while the fungal and aflatoxin contamination may indicate poor postharvest handling, transport, and storage conditions of baobab fruits along the baobab value chain.

Study on mycotoxin contamination in South African food spices

A validated QuEChERS-based method was used to investigate the occurrence of mycotoxins in 70 South African food spices [coarse chilli (n=14), ground chilli (n=4), paprika (n=7), ginger (n=5), chicken spices (n=8), onion spices (n=8), beef spices (n=5), Mexican chilli (n=9), vegetable spice (n=1), fruit chutney spices (n=4), and cheese spices (n=5)]. Mycotoxins were quantified using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Results revealed that 40% of the samples were contaminated with aflatoxin B1, aflatoxin G1, ochratoxin A, sterigmatocystin, 3-acetyldeoxynivalenol, fumonisin B1, fumonisin B2 and/or roquefortine C. The contamination levels for aflatoxin B1 ranged from 3-19 μg/kg; aflatoxin G1, 10-11 μg/kg; ochratoxin A, 4-20 μg/kg; fumonisin B1 104-591 μg/kg; fumonisin B2, 64-5,897 μg/kg; sterigmatocystin, 11-18 μg/kg; 3-acetyldeoxynivalenol, 42-46 μg/kg; and roquefortine C, 17-57 μg/kg. Mycotoxins co-occurred in 11% of the spice samples. Amongst the samples analysed in this study, paprika had the highest positives (100%) for the determined mycotoxins. Previous reports on mycotoxin contamination in spices, focused on the incidence of aflatoxins and ochratoxin A, but not on the multi-mycotoxin profile in South African spices. This study thus provides a comprehensive assessment of mycotoxin contamination of spices in South Africa.

Engaging One Health for Non-Communicable Diseases in Africa: Perspective for Mycotoxins

The role of mycotoxins-e.g., aflatoxins, ochratoxins, trichothecenes, zearalenone, fumonisins, tremorgenic toxins, and ergot alkaloids-has been recognized in the etiology of a number of diseases. In many African countries, the public health impact of chronic (indoor) and/or repeated (dietary) mycotoxin exposure is largely ignored hitherto, with impact on human health, food security, and export of African agricultural food products. Notwithstanding, African scientific research reached milestones that, when linked to findings gained by the international scientific community, make the design and implementation of science-driven governance schemes feasible. Starting from Nigeria as leading African Country, this article (i) overviews available data on mycotoxins exposure in Africa; (ii) discusses new food safety issues, such as the environment-feed-food chain and toxic exposures of food producing animals in risk assessment and management; (iii) identifies milestones for mycotoxins risk management already reached in West Africa; and (iv) points out preliminary operationalization aspects for shielding communities from direct (on health) and indirect (on trade, economies, and livelihoods) effects of mycotoxins. An African science-driven engaging of scientific knowledge by development actors is expected therefore. In particular, One health/One prevention is suggested, as it proved to be a strategic and sustainable development framework.

Moisture content and its impact on aflatoxin levels in ready-to-use red chillies

Moisture content (MC) and aflatoxin contamination were analysed to determine Red Chilli quality. A wide range (9.1-19.8%) of MC with a mean value of 11.4 ± 2.4% was found. Of 116 chilli samples, about 37% had low MC (<10%), 29.4% had medium-low MC (10-12%), 18.9% had medium-high MC (12 < MC < 14%) and 14.7% were above 14%. These four chilli groups had average aflatoxin levels of 2.1 ± 1.1, 5.3 ± 4.2, 8.9 ± 5.9 and 37 ± 20 µg/Kg, respectively. A direct relationship between moisture and aflatoxin content was found. The data best fitted a polynomial trend (R² = 0.89). The obtained equation could be utilised to assess aflatoxin levels based on MC. This study highlights the importance of using properly dried chillies with low MC, that is, ≤10%, to minimise health hazards associated with aflatoxin contamination.

Natural Occurrence of Mycotoxins in Food and Feed: Pakistan Perspective

Fungi are commonly present in the environment and can grow under favorable conditions on an extensive variety of substrates. During harvesting, handling, storage, and distribution, agricultural commodities are subjected to infection by toxigenic molds, which may cause spoilage and produce toxic metabolites called mycotoxins. Fungal contamination of various food commodities with consequent exposure of the community to mycotoxins is a hazard that may exist depending on environmental factors, crop health, and soil conditions. Mycotoxins represent serious consequences due to substantial economic loss and risk to health. The environmental conditions of Pakistan with its mostly warm temperature are conducive to growth of toxigenic fungi resulting in mycotoxin production in different food items. Moreover, the poor conditions of storage and deficiency in regulatory measures in food quality control worsen the situation in the country. This review encompasses mycotoxin contamination of food and feed in Pakistan. High concentrations of mycotoxins are found in some commodities that are used on a daily basis in Pakistan, which may be a concern depending on dietary variety and health conditions of individuals in the population. Therefore, the mycotoxin contamination of foodstuff with exceeding levels represents a serious health hazard for the local population. There is a need to conduct more studies to analyze mycotoxin occurrence in all types of food commodities throughout the country. For consumer safety and the country's economy, the regulatory authorities should take into account this issue of contamination, and control strategies should be implemented and the quality control system of food improved.

Food safety management systems performance in African food processing companies: a review of deficiencies and possible improvement strategies

This study seeks to provide insight into current deficiencies in food safety management systems (FSMS) in African food-processing companies and to identify possible strategies for improvement so as to contribute to African countries' efforts to provide safe food to both local and international markets. This study found that most African food products had high microbiological and chemical contamination levels exceeding the set (legal) limits. Relative to industrialized countries, the study identified various deficiencies at government, sector/branch, retail and company levels which affect performance of FSMS in Africa. For instance, very few companies (except exporting and large companies) have implemented HACCP and ISO 22000:2005. Various measures were proposed to be taken at government (e.g. construction of risk-based legislative frameworks, strengthening of food safety authorities, recommend use of ISO 22000:2005, and consumers' food safety training), branch/sector (e.g. sector-specific guidelines and third-party certification), retail (develop stringent certification standards and impose product specifications) and company levels (improving hygiene, strict raw material control, production process efficacy, and enhancing monitoring systems, assurance activities and supportive administrative structures). By working on those four levels, FSMS of African food-processing companies could be better designed and tailored towards their production processes and specific needs to ensure food safety.

An overview on mycotoxin contamination of foods in Africa

Mycotoxins are fungal secondary metabolites that contaminate various feedstuffs and agricultural crops. The contamination of food by mycotoxins can occur before production, during storage, processing, transportation or marketing of the food products. High temperature, moisture content and water activity are among the predisposing factors that facilitate the production of mycotoxins in food. Aflatoxins, ochratoxins, fumonisins, deoxynivalenol and zearalenone are all considered the major mycotoxins produced in food and feedstuffs. In Africa, mycotoxin contamination is considered to be a major problem with implications that affect human and animal health and economy. Aflatoxin-related hepatic diseases are reported in many African countries. Ochratoxin and fumonisin toxicity in humans and animals is widespread in Africa. The available, updated information on the incidence of mycotoxin contamination, decontamination and its public health importance in Africa is lacking. The aim of this review is to highlight, update and discuss the available information on the incidence of mycotoxins in African countries. The public health implications and the recommended strategies for control of mycotoxins in food and agricultural crops are also discussed.

Aflatoxins in various food from Istanbul, Turkey

The present work reports the total aflatoxin and aflatoxin B1 levels in 62 food samples from Istanbul, Turkey. The total aflatoxin content in dried American cucumber, squash, tomato, okra and saffron samples was found to be 1.7 μg/kg. AFB1 levels in five dried vegetables (red bell pepper, American cucumber, squash, tomato and okra), two tea (linden and jasmine flower) and three spice samples (cardamom, galangal and saffron) were 1 μg/kg. Of the tested samples, 76% exceeded legal limits of total aflatoxin. The highest levels were determined in chestnut (232.9 μg/kg), nutmeg (206.1 μg/kg) and sumac (182.5 μg/kg). These findings confirm the existing knowledge that food should be regularly and effectively controlled.

A review on aflatoxin contamination and its implications in the developing world: a sub-Saharan African perspective

Mycotoxins contamination in some agricultural food commodities seriously impact human and animal health and reduce the commercial value of crops. Mycotoxins are toxic secondary metabolites produced by fungi that contaminate agricultural commodities pre- or postharvest. Africa is one of the continents where environmental, agricultural and storage conditions of food commodities are conducive of Aspergillus fungi infection and aflatoxin biosynthesis. This paper reviews the commodity-wise aetiology and contamination process of aflatoxins and evaluates the potential risk of exposure from common African foods. Possible ways of reducing risk for fungal infection and aflatoxin development that are relevant to the African context. The presented database would be useful as benchmark information for development and prioritization of future research. There is need for more investigations on food quality and safety by making available advanced advanced equipments and analytical methods as well as surveillance and awareness creation in the region.

Developments in mycotoxin analysis: an update for 2009-2010

This review highlights developments in mycotoxin analysis and sampling over a period between mid-2009 and mid-2010. It covers the major mycotoxins aflatoxins, Alternaria toxins, ergot alkaloids, fumonisins, ochratoxin, patulin, trichothecenes, and zearalenone. New and improved methods for mycotoxins continue to be published. Immunological-based method developments continue to be of wide interest in a broad range of formats. Multimycotoxin determination by LC-MS/MS is now being targeted at the specific ranges of mycotoxins and matrices of interest or concern to the individual laboratory. Although falling outside the main emphasis of the review, some aspects of natural occurrence have been mentioned, especially if linked to novel method developments.

Production and migration of mycotoxins in sweet pepper analyzed by Multimycotoxin LC-MS/MS

In this work the presence and migration behavior of mycotoxins formed in sweet pepper, inoculated by Fusarium species involved in internal fruit rot, were investigated. Two different commercial sweet pepper cultivars were inoculated with two different Fusarium proliferatum isolates that were sampled from diseased peppers. After 10 days of incubation at 20 °C in a closed container, the lesion caused by the fungal infection was dissected. Around the lesion, up to three concentric rings of pepper fruit tissue with a width of 5 mm were cut out and analyzed using a multimycotoxin LC-MS/MS method. The analyses resulted in the detection of beauvericin and fumonisins B(1), B(2), and B(3). Beauvericin was detected only in the lesions (95%), and the levels varied between 67 and 73800 μg/kg. Fumonisins B(1), B(2), and B(3) were detected in the lesions and in the surrounding tissue, indicating migration of these toxins into healthy parts of the sweet pepper. In the lesion the fumonisin B(1) level varied between 690 and 104000 μg/kg. Even in the outer ring fumonisin B(1) was still present. Mostly it was present at a lower level than in the lesion, with a maximum level of 556 μg/kg. A similar migration behavior was obtained for fumonisins B(2) and B(3), but lower levels were detected in the lesions, up to 10900 and 1287 μg/kg, respectively. The analysis of 20 pepper samples resulted in the detection of beauvericin or alternariol. Seven samples were contaminated, and the level of beauvericin was 124 μg/kg (N = 1), whereas the level of alternariol varied from below the LOQ (6.6 μg/kg) to 101 μg/kg (N = 6).