ReviewChallenges and issues concerning mycotoxins contamination in oil seeds and their edible oils: Updates from last decade
Introduction
Contamination of agri-food commodities by mycotoxins-producing fungi (molds) and their mycotoxins is a recurring food safety problems world over. In recent years, serious concerns are being raised by consumers as well as by health professionals for the presence of various toxigenic fungi or their secondary metabolites (as mycotoxins) in food and feed. This concern is mainly due to increased evidence based research knowledge, and the available monographs related to the health effects caused by ingestion of food or feed contaminated by toxigenic fungi in humans and livestock.
Majority of the mycotoxins reported till date are potentially carcinogenic, teratogenic, tremorogenic, nephrotoxic, immunotoxic or hemorrhagic. In addition, most of the mycotoxins are capable of causing dermatitis in both humans and livestock. Some of the common mycotoxins identified in human food and animal feeds include aflatoxins, ochratoxins, trichothecenes (deoxynivalenol, nivalenol), zearalenone, fumonisins, patulin, citrinin, cyclopiazonic acid, sporidesmins, slaframine, stachybotryotoxin, and phomopsin (Bhat, Rai, & Karim, 2010). Contamination of human food and livestock feed by fungi and their respective toxins presents a serious food safety issue globally, leading to incredible yield and economic losses. As per the International Agency for Research on Cancer (IARC), aflatoxins are considered group 1, and ochratoxin A (OTA) and fumonisins (B1 and B2) as group 2B possible human carcinogens, while zearalenone is a group 3 carcinogen. Zinedine and Mañes (2009) have opined that mycotoxins, being heat-stable, represent an impending risk for human and animal health. In majority of the cases, mycotoxin-producing fungi is reported to belong to genera of Aspergillus, Fusarium, and Penicillium (Bhat et al., 2010, Kumar et al., 2008).
Today, with widely available reports and updated database on fungal occurrence and mycotoxins contamination in marketed commodities, health protection bodies have imposed stringent regulations, especially for imported commodities (Bhat et al., 2010). Fungal contamination in a seed generally occurs either during pre-harvest or during postharvest conditions. In majority of the instances, fungi might be present as an endophyte and invisible to the naked eye. Improper storage conditions and other eco-physiological factors, especially prevailing in the tropics and sub-tropics (wherein high temperature and humidity prevail) contribute immensely for the rapid growth of molds. These fungi can thrive even at low moisture and water activity levels and produce mycotoxins.
In recent years, edible oils (fat) extracted from plant seeds have gained immense popularity over animal-based fats, mainly due to their potential therapeutic/health-promoting potential. Several reports are available on fungal contamination of various oil-yielding seeds, as well as on the presence of mycotoxins in the extracted oil. Contamination of oil seeds by toxigenic molds is a menace, as the seeds and the oil extracted from the infected seeds tend to become unfit for consumption. Accordingly, some of the world’s health-governing bodies [such as the Food and Agriculture Organization (FAO), Codex Alimentarius Commission (CODEX), EU Commission and the World Health Organization (WHO)] have put forth stringent laws/regulations for the maximum tolerable levels (limits) of mycotoxins contamination in oilseeds, some of which are depicted in Table 1.
To our knowledge, no review is available wherein various data and reports are compiled to provide comprehensive information on the presence of toxigenic fungi or the mycotoxin level in oil yielding seeds and their edible oil. In this review, we have attempted to disseminate details on the presence of various toxigenic fungi (molds) colonizing some of the common and popular edible oil yielding seeds and report on the levels of mycotoxins present in their oils. In addition, we have aimed to provide sufficient baseline informations, which are envisaged to be useful for both health-conscious consumers as well as for all public health agencies.
Section snippets
Fungal contamination and mycotoxins level
Fungal contamination and levels of mycotoxins present in an oil yielding seed and their oil can differ from region to region. Generally, high humidity and warm temperature favours the growth of toxigenic molds, which holds true for both the tropical and sub-tropical regions. Presence of toxigenic molds is also well known in cold and temperate regions, but is based on a particular commodity. Some of the vital factors influencing the occurrence of mycotoxins in food and feed are depicted in Fig. 1
Oil seed cake and mycotoxins
Oilseed cake, which is the dense residue remaining post seed pressing and extraction of oil, is a valuable protein rich product used as a feed for livestock. Generally, these residues are fed to animals, either singly or in combination with the other oil cake obtained from others seeds (e.g. soybean mixed with sunflower or rapeseed or vice versa). This oilcake can get contaminated by various toxigenic fungi either during short- or long-term storage periods. Some of the pathogenic fungal strains
Fate of mycotoxins during oil extraction and refining
Several reports are available on the reduction of mycotoxins after employing conventional food processing techniques. The effect of thermal processing, extrusion cooking, milling, and brewing is shown to reduce the mycotoxins levels in various agricultural commodities (Bhat et al., 2010, Kabak, 2009, Park and Kim, 2006). However, very few reports are available on the fate of mycotoxins during oil extraction from seeds and its refining process. Hence, only a few of the reports are discussed in
Conclusions
Based on the available reports, it is a well-established fact that commercial oil yielding seeds and their edible oils can get contaminated by various toxigenic fungi and mycotoxins, both during pre- and postharvest stages. Additionally, the by-product in the form of oil cake obtained after oil extraction (commonly used as an animal feed), can be contaminated by fungi and their toxins.
As of today, there are still major gaps that exist with regard to the various research aspects relevant to
Conflict of interest
The authors declare that ‘NO Conflict of interest’ exist in this review.
Acknowledgements
The first author (RB) sincerely acknowledges relevant authorities at the Fiji National University (FNU), Fiji Islands for all the necessary facilities provided.
References (95)
- et al.
Occurrence of Fusarium species and trichothecenes in Nigerian maize
International Journal of Food Microbiology
(2007) Natural occurrence of some mycotoxins in local and imported corn grains (Zea mays L.) in Egypt
Toxicology Letter
(2007)- et al.
Mycoflora and mycotoxins in field samples of Brazil nuts
Food Control
(2012) - et al.
Mycotoxin occurrence in corn meal and flour traded in São Paulo, Brazil
Food Control
(2005) Mycotoxin contamination of the feed supply chain: Implications for animal productivity and feed security
Animal Feed Science and Technology
(2012)- et al.
Determination of aflatoxin levels in nuts and their products consumed in South Korea
Food Chemistry
(2007) - et al.
Natural occurrence of mycotoxins in peanut cake from Nigeria
Food Control
(2012) - et al.
Occurrence and exposure assessment of Fusarium mycotoxins in maize germ, refined corn oil and margarine
Food and Chemical Toxicology
(2013) - et al.
Natural occurrence of Fusarium and subsequent fumonisin contamination in preharvest and stored maize in Benin, West Africa
International Journal of Food Microbiology
(2005) - et al.
The influence of storage practices on aflatoxin contamination in maize in four agroecological zones of Benin
West African Journal of Stored Product Research
(2000)
Mycotoxin research and mycoflora in some commercially important agricultural commodities
Crop Protection
Aflatoxin occurrence in nuts and commercial nutty products in Malaysia
Food Control
Occurrence of fumonisins B1 and B2 in broa, a typical Portuguese maize bread
International Journal of Food Microbiology
Aflatoxins in stored maize and rice grains in Liaoning Province, China
Journal of Stored Product Research
Post-harvest control strategies: Minimizing mycotoxins in the food chain
International Journal of Food Microbiology
Ochratoxin A and Aspergillus section Nigri in peanut seeds at different months of storage in Córdoba, Argentina
International Journal of Food Microbiology
Citrinin mycotoxin recognition and removal by naked magnetic nanoparticles
Food Chemistry
Whole sunflower seeds as a source of polyunsaturated fatty acids for grazing dairy cows: Effects on metabolic profiles and resumption of postpartum ovarian cyclicity
Livestock Science
Occurrence of contaminants in foods commonly consumed in Bahrain
Food Control
Prevalence and factors associated with aflatoxin contamination of peanuts from Western Kenya
International Journal of Food Microbiology
Distribution of fungi and aflatoxins in a stored peanut variety
Food Chemistry
Occurrence of ochratoxin a contamination and detection of ochratoxigenic Aspergillus species in retail samples of dried fruits and nuts
Journal of Food Protection
Characterization of Aspergillus section Flavi isolated from organic Brazil nuts using a polyphasic approach
Food Microbiology
Occurrence of fourteen mycotoxins in tiger-nuts
Food Control
Fungal contamination and mycotoxin natural occurrence in oats for race horses feeding in Argentina
Animal Feed Science and Technology
Survey of Fusarium toxins in foodstuffs of plant origin marketed in Germany
International Journal of Food Microbiology
Natural occurrence of Fusarium toxins in soy food marketed in Germany
International Journal of Food Microbiology
Natural occurrence of 16 Fusarium toxins in edible oil marketed in Germany
Food Control
Nuts and dried fruits: Natural occurrence of emerging Fusarium mycotoxins
Food Control
Aflatoxin contamination of peanuts at harvest in China from 2010 to 2013 and its relationship with climatic conditions
Food Control
Occurrence and legislation of mycotoxins in food and feed from Morocco
Food Control
Aflatoxin and fumonisins contamination of commercial corn (Zea mays) hybrids in Mississippi
Journal of Agricultural and Food Chemistry
Mycobiota of sunflower seeds and samples collected from a vegetable oil refinery located in Tamilnadu, India
Mycological Progress
Mycotoxins – Present status and future concerns
Comprehensive Reviews in Food Science and Food Safety
Effects of genotype and environmental factors on rape seed contamination with mycotoxins and mycotoxin-producing fungi
Ekologija
Effect of industrial processing on the distribution of aflatoxins and zearalenone in maize-milling fractions
Journal of Agricultural and Food Chemistry
Natural occurrence of aflatoxins, deoxynivalenol, fumonisins and zearalenone in maize from Entre Rios Province, Argentina
Mycotoxin Research
A survey of aflatoxins in peanuts and pistachios: Comparison with some data published in 1989 in Spain
Alimentaria
Application of a model to assess aflatoxin risk in peanuts
The Journal of Agricultural Science
Dietary phospholipids, hepatic lipid metabolism and cardiovascular disease
Current Opinion in Lipidology
Microwave drying and disinfestation of Brazil nut seeds
Food Control
Aflatoxin contamination in peanuts commercially available in Sri Lanka
Vidyodaya Journal of Science
Management and prevention of mycotoxins in peanuts
Food Additives & Contaminants A: Chemistry, Analysis, Control, Exposure and Risk Assessment
Commission regulation (EC) No. 466/2001of 8 March 2001 setting maximum levels for certain contaminants in foodstuffs
Official Journal European Communities
Preliminary data on the presence of mycotoxins (ochratoxin A, citrinin and aflatoxin B1) in black table olives ‘‘Greek style” of Moroccan origin
Molecular Nutrition & Food Research
Food and Agriculture Organization, worldwide regulations for mycotoxins in food and feed in 2003
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