Mycotoxin concentrations in rice from three climatic locations in Africa as affected by grain quality, production site, and storage duration

Aflatoxins in the rice production chain: A review on prevalence, detection, and decontamination strategies

Rice (Oryza sativa L.) is one of the most consumed cereals that along with several important nutritional constituents typically provide more than 21% of the caloric requirements of human beings. Aflatoxins (AFs) are toxic secondary metabolites of several Aspergillus species that are prevalent in cereals, including rice. This review provides a comprehensive overview on production factors, prevalence, regulations, detection methods, and decontamination strategies for AFs in the rice production chain. The prevalence of AFs in rice is more prominent in African and Asian than in European countries. Developed nations have more stringent regulations for AFs in rice than in the developing world. The contamination level of AFs in the rice varied at different stages of rice production chain and is affected by production practices, environmental conditions comprising temperature, humidity, moisture, and water activity as well as milling operations such as de-husking, parboiling, and polishing. A range of methods including chromatographic techniques, immunochemical methods, and spectrophotometric methods have been developed, and used for monitoring AFs in rice. Chromatographic methods are the most used methods of AFs detection followed by immunochemical techniques. AFs decontamination strategies adopted worldwide involve various physical, chemical, and biological strategies, and even using plant materials. In conclusion, adopting good agricultural practices, implementing efficient AFs detection methods, and developing innovative aflatoxin decontamination strategies are imperative to ensure the safety and quality of rice for consumers.

Zearalenone contamination in maize, its associated producing fungi, control strategies, and legislation in Sub-Saharan Africa

The fungal genus Fusarium contains many important plant pathogens as well as endophytes of wild and crop plants. Globally, Fusarium toxins in food crops are considered one of the greatest food safety concerns. Their occurrence has become more pronounced in Africa in recent times. Among the major Fusarium mycotoxins with food and feed safety concerns, zearalenone is frequently detected in finished feeds and cereals in Africa. However, the impact of indigenous agricultural practices (pre- and postharvest factors) and food processing techniques on the prevalence rate of Fusarium species and zearalenone occurrence in food and feed have not been collated and documented systematically. This review studies and analyzes recent reports on zearalenone contamination in maize and other cereal products from Africa, including its fungi producers, agronomic and climate variables impacting their occurrences, preventive measures, removal/decontamination methods, and legislations regulating their limits. Reports from relevant studies demonstrated a high prevalence of F. verticillioides and F. graminearum as Africa's main producers of zearalenone. Elevated CO2 concentration and high precipitation may carry along an increased risk of zearalenone contamination in maize. African indigenous processing methods may contribute to reduced ZEA levels in agricultural products and foods. Most African countries do not know their zearalenone status in the food supply chain and they have limited regulations that control its occurrence.

Determination of aflatoxins in rice from Penang, Malaysia by dispersive liquid-liquid micro-extraction and LC-MS/MS

Rice is one of the crops cultivated in Malaysia, and it is the main diet for most of the population. In this study, dispersive liquid-liquid micro-extraction (DLLME) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) were used to develop, optimise and validate a reliable, easy-to-use and quick approach to detect aflatoxin B1 (AFB1), aflatoxin B2 (AFB2), aflatoxin G1 (AFG1) and aflatoxin G2 (AFG2). The extraction recoveries in DLLME were enhanced by the addition of 5% salt, utilising chloroform as the extraction solvent and acetonitrile as the dispersive solvent. The DLLME parameters - the extraction solvent volume, salt concentration and dispersive solvent volume were optimised with Box-Behnken design (BBD) and response surface methodology (RSM). Under optimised experimental conditions, excellent linearity was obtained with a limit of detection (LOD) ranging from 0.125 to 0.25 ng g-1, a limit of quantitation (LOQ) ranging from 0.25 to 0.3 ng g-1 and a correlation value (R2) of 0.990. The matrix effects were between -11.1% and 19.9%, and recoveries ranged from 87.4% to 117.3%. The optimised and validated method was used effectively to assess aflatoxins contamination in 20 commercial rice samples collected from local supermarkets in Penang, Malaysia. AFB1 was detected at 0.41-0.43 ng g-1 in two rice samples, below the regulatory limit.

Controlling aflatoxin in maize: The effects of varieties, packaging materials, and agroecological zones

Contamination of crops by aflatoxin is rampant in warm regions worldwide, including Sub-Sahara Africa. Contamination of maize and other foodstuffs with aflatoxin seriously threatens the health of humans and animals. The experimental design used was 2 × 2 × 3 factorial, laid out in a complete randomized design (CRD) consisting of two agroecological zones, two varieties, and three different packaging materials. At the end of the six months of storage, there was no contamination of the maize with aflatoxin G1. Again, there was no contamination of maize stored in the Forest zone with aflatoxin B1. High contamination levels of aflatoxin B1 (8.91 μg/kg), aflatoxin B2 (10.74 μg/kg), and aflatoxin G2 (14.49 μg/kg) occurred in the Wangdataa variety stored in jute. Purdue Improved Crop Storage (PICS) bags recorded lower contamination levels than jute and polypropylene (PP). Contamination was higher in the Savannah zone than in the Forest zone. The three packaging materials used gave maximum protection to all the maize stored in the Forest against aflatoxin B1 and aflatoxin G1. Farmers, traders, and all aggregators of maize in the Savannah zone should be discouraged from using jute bags to store maize in the Savannah zone for an extended period. Opeaburo should be planted and stored in the Savannah zone rather than Wangdataa. Farmers should be encouraged to use PICS bags to store maize in the Savannah zone to control aflatoxin B1, aflatoxin B2, and aflatoxin G2.

A review of toxigenic fungi and mycotoxins in feeds and food commodities in West Africa

Fungal contamination is a threat to food safety in West Africa with implications for food and feed due to their climate, which is characterised by high temperatures and high relative humidity, which are environmental favourable for fast fungal growth and mycotoxin production. This report gives perspective on studies on toxigenic fungi (Aspergillus, Fusarium and Penicillium) and their toxins, mainly aflatoxins, fumonisins and ochratoxins commonly found in some West African countries, including Benin, Burkina Faso, Gambia, Ghana, Ivory Coast, Mali, Nigeria, Senegal, Sierra Leone, and Togo. Only four of these countries have mycotoxins regulations in place for feeds and food products (Ghana, Ivory Coast, Nigeria, and Senegal). Food commodities that are widely consumed and were thoroughly investigated in this region include cereals, peanuts, cassava chips (flakes), cassava flour, chilies, peanuts, locust beans, melon, and yam products. In conclusion, authorities and scientists needed to consider research and approaches to monitor mycotoxins in foods and feeds produced and consumed in West Africa.

Aflatoxin B1 in Rice: Effects of Storage Duration, Grain Type and Size, Production Site, and Season

ABSTRACT

Our study evaluated aflatoxin B1 (AFB1) levels in packed rice marketed in Lebanon and determined the exposure to this toxin from rice consumption. A total of 105 packed white, parboiled, and brown rice bags were collected. Enzyme-linked immunosorbent assay was used to measure AFB1. A comprehensive food frequency questionnaire was completed by 500 participants to determine patterns of rice consumption and, subsequently, the exposure levels to AFB1 from rice consumption in Lebanon. AFB1 was detected in all rice samples (100%). The average concentration ± standard deviation of AFB1 was 0.5 ± 0.3 μg/kg. Contamination ranged between 0.06 and 2.08 μg/kg. Moisture content in all rice samples was below the recommended percentage (14%). Only 1% of the samples had an AFB1 level above the European Union limit (2 μg/kg). Brown rice had a significantly higher AFB1 level than white and parboiled rice (P = 0.02), while a significant difference was found between both collections for the same brands (P = 0.016). Packing season, packing country, country of origin, presence of a food safety management certification, grain size, and time between packing and purchasing had no significant effect. Exposure to AFB1 from rice consumption in Lebanon was calculated as 0.1 to 2 ng/kg of body weight per day.

HIGHLIGHTS

Simultaneous determination of trichothecene mycotoxins in cereals by LC-MS/MS

This study was designed to determine the residual trichothecene mycotoxins in cereal samples. The optimal solvent for extraction was 84% (v/v) aqueous acetonitrile with 1% (v/v) formic acid. The best performing clean-up method was dispersive-solid phase with a mixture octadecyl silica and primary-secondary amine. The recoveries for the studied mycotoxins ranged from 83.3 to 92.8%. The methodology was successfully applied for monitoring 100 cereal samples obtained from a Korean market. The bean sample were found to be co-contamination with deoxynivalenol and HT-2 toxin. Deoxynivalenol possessed the highest detection freauency (4/100) and amount (727.38 µg/kg) among the trichothecene mycotoxins. The hazard index was less than 1.0 for all the observed mycotoxins in all cereal samples except one white rice sample (1.2681). This results indicated that periodic risk assessments of trichothecene mycotoxin through cereal intake are necessary for the health and safety.

Urinary Biomarkers of Mycotoxin Induced Nephrotoxicity-Current Status and Expected Future Trends

The intensifying world-wide spread of mycotoxigenic fungal species has increased the possibility of mycotoxin contamination in animal feed and the human food chain. Growing evidence shows the deleterious toxicological effects of mycotoxins from infants to adults, while large population-based screening programs are often missing to identify affected individuals. The kidney functions as the major excretory system, which makes it particularly vulnerable to nephrotoxic injury. However, few studies have attempted to screen for kidney injury biomarkers in large, mycotoxin-exposed populations. As a result, there is an urgent need to screen them with sensitive biomarkers for potential nephrotoxicity. Although a plethora of biomarkers have been tested to estimate the harmful effects of a wide spectrum of toxicants, β₂-microglobulin (β₂-MG) and N-acetyl-β-D-glucosaminidase (NAG) are currently the dominant biomarkers employed routinely in environmental toxicology research. Nevertheless, kidney injury molecule 1 (KIM-1) and neutrophil gelatinase-associated lipocalin (NGAL) are also emerging as useful and informative markers to reveal mycotoxin induced nephrotoxicity. In this opinion article we consider the nephrotoxic effects of mycotoxins, the biomarkers available to detect and quantify the kidney injuries caused by them, and to recommend biomarkers to screen mycotoxin-exposed populations for renal damage.

Determination of patulin in products containing dried fruits by Enzyme-Linked Immunosorbent Assay technique Patulin in dried fruits

The era of globalization causes that the export and import of food from different continents of the world are becoming more and more common, which may directly contribute to the increase in pollution in them. The presence of mycotoxin in food is an ubiquitous problem. There is very limited information on the possible influence of the composition of herbal mixtures on the presence of mycotoxins in them, which is an area where research can be expanded. The aim of this study was to determine patulin (PAT) in commercial products containing dried elderberry, rose, blueberry, rowan, hawthorn, and chokeberry fruits by enzyme-linked immunosorbent assay technique. Research using this technique allowed for considering the possible influence of the composition of herbal mixtures on the concentration of patulin in them. Patulin was detected in all analyzed samples with wide range of Collapse

Key Words

• ELISA
• dried fruits
• herbal blends
• patulin
• rowan fruit
• tea

Collapse

MESH Headings Collapse

Grants Collapse

Affiliation(s)

Anna Przybylska Department of Toxicology and BromatologyFaculty of PharmacyL. Rydygier Collegium Medicum in BydgoszczNicolaus Copernicus University in TorunBydgoszczPoland
Agnieszka Chrustek Department of Pathobiochemistry and Clinical ChemistryFaculty of PharmacyL. Rydygier Collegium Medicum in BydgoszczNicolaus Copernicus University in TorunBydgoszczPoland
Dorota Olszewska‐Słonina Department of Pathobiochemistry and Clinical ChemistryFaculty of PharmacyL. Rydygier Collegium Medicum in BydgoszczNicolaus Copernicus University in TorunBydgoszczPoland
Marcin Koba Department of Toxicology and BromatologyFaculty of PharmacyL. Rydygier Collegium Medicum in BydgoszczNicolaus Copernicus University in TorunBydgoszczPoland
Stefan Kruszewski Medical Physics DivisionBiophysics DepartmentFaculty of PharmacyL. Rydygier Collegium Medicum in BydgoszczNicolaus Copernicus University in TorunBydgoszczPoland

Collapse

Grain quality evaluation of japonica rice effected by cultivars, environment, and their interactions based on appearance and processing characteristics

Appearance and processing characteristics of 45 japonica rice samples, collected from different regions in Jiangsu province, were investigated and evaluated in this study. Specifically, the chalkiness degree had been presented significant differences among different cultivars and regions. The average chalkiness degree varied from 6.81% to 15.34% for different regions and from 1.93% to 28.31% for different cultivars. The minimum head rice rate of cultivars from four regions, NJ9108 (HA), was 80.5%. The AC of CNG10, HD5, and PJ surpassed 13.68% and lower than 11.33% for the others. The protein content ranged from 6.1% to 11%, and the taste value was significantly different among cultivars. In addition, the RVA curves of the samples were similar, but the peak viscosities of NG8 and NJ5055 were higher than others, and there were significant differences in RVA traits among regions. Cultivars were the main reasons for the difference in appearance and processing quality of japonica rice, while environmental factors had leaded to the change of rice composition, texture, and gelatinization.

Multiple Mycotoxins in Kenyan Rice

Multiple mycotoxins were tested in milled rice samples (n = 200) from traders at different milling points within the Mwea Irrigation Scheme in Kenya. Traders provided the names of the cultivar, village where paddy was cultivated, sampling locality, miller, and month of paddy harvest between 2018 and 2019. Aflatoxin, citrinin, fumonisin, ochratoxin A, diacetoxyscirpenol, T2, HT2, and sterigmatocystin were analyzed using ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC–MS/MS). Deoxynivalenol was tested using enzyme-linked immunosorbent assay (ELISA). Mycotoxins occurred in ranges and frequencies in the following order: sterigmatocystin (0–7 ppb; 74.5%), aflatoxin (0–993 ppb; 55.5%), citrinin (0–9 ppb; 55.5%), ochratoxin A (0–110 ppb; 30%), fumonisin (0–76 ppb; 26%), diacetoxyscirpenol (0–24 ppb; 20.5%), and combined HT2 + T2 (0–62 ppb; 14.5%), and deoxynivalenol was detected in only one sample at 510 ppb. Overall, low amounts of toxins were observed in rice with a low frequency of samples above the regulatory limits for aflatoxin, 13.5%; ochratoxin A, 6%; and HT2 + T2, 0.5%. The maximum co-contamination was for 3.5% samples with six toxins in different combinations. The rice cultivar, paddy environment, time of harvest, and millers influenced the occurrence of different mycotoxins. There is a need to establish integrated approaches for the mitigation of mycotoxin accumulation in the Kenyan rice.

Physical, nutritional, and sensory quality of rice-based biscuits fortified with safou (Dacryodes edulis) fruit powder

The reduction of postharvest losses in rice and safou is imperative to increase productivity in their respective value chains. In this study, fine broken rice grains were used to produce rice flour and subsequently rice-based biscuits. The biscuits were further fortified with safou powder, and the physical, nutritional, and sensory quality and stability during storage of the different types of biscuits were analyzed using standard methods. Fine or nonsandy biscuits had peak particle size of 500 µm, while medium (slightly sandy) and large (sandy) biscuits had peak particle sizes of 1,000 µm and 1,400 µm, respectively. The hardness varied from 5.7 ± 2.3 N for biscuits with large particles to 16.1 ± 4.4 N for biscuits with fine particles. Fortification of biscuits with sour safou increased the protein and amino acid content of the biscuits. Tryptophan was absent in both safou and the biscuits produced. There was an increase in phosphorus, potassium, calcium, magnesium, copper, iron, manganese, and aluminum following fortification with safou. Nonsandy biscuits dissolved faster in the mouth (melt) during consumption than the other biscuits although most of the biscuits were perceived to be low in melting and buttery. Nonsandy biscuits were rated as "very good," while slightly sandy and sandy were rated as "good." Safou rice-based biscuits were perceived as "very good," while simple rice biscuits were perceived as "good." Fortification of rice biscuits with safou increased the protein, essential amino acid, and mineral contents of the biscuits with very appreciable taste. These biscuits can be used to help fight protein, iron, and zinc malnutrition and in mitigating postharvest losses of underutilized broken rice and safou especially sour safou.

Toxicological and Medical Aspects of Aspergillus-Derived Mycotoxins Entering the Feed and Food Chain

Due to Earth's changing climate, the ongoing and foreseeable spreading of mycotoxigenic Aspergillus species has increased the possibility of mycotoxin contamination in the feed and food production chain. These harmful mycotoxins have aroused serious health and economic problems since their first appearance. The most potent Aspergillus-derived mycotoxins include aflatoxins, ochratoxins, gliotoxin, fumonisins, sterigmatocystin, and patulin. Some of them can be found in dairy products, mainly in milk and cheese, as well as in fresh and especially in dried fruits and vegetables, in nut products, typically in groundnuts, in oil seeds, in coffee beans, in different grain products, like rice, wheat, barley, rye, and frequently in maize and, furthermore, even in the liver of livestock fed by mycotoxin-contaminated forage. Though the mycotoxins present in the feed and food chain are well documented, the human physiological effects of mycotoxin exposure are not yet fully understood. It is known that mycotoxins have nephrotoxic, genotoxic, teratogenic, carcinogenic, and cytotoxic properties and, as a consequence, these toxins may cause liver carcinomas, renal dysfunctions, and also immunosuppressed states. The deleterious physiological effects of mycotoxins on humans are still a first-priority question. In food production and also in the case of acute and chronic poisoning, there are possibilities to set suitable food safety measures into operation to minimize the effects of mycotoxin contaminations. On the other hand, preventive actions are always better, due to the multivariate nature of mycotoxin exposures. In this review, the occurrence and toxicological features of major Aspergillus-derived mycotoxins are summarized and, furthermore, the possibilities of treatments in the medical practice to heal the deleterious consequences of acute and/or chronic exposures are presented.