A Review Of The Fundamental Factors And Processes Leading To The Accumulation Of Aflatoxins In Cereal Crops

Abstract

Aflatoxins (AFs) contamination of cereals is considered one of the greatest food safety concerns worldwide. Occurrence of AFs in maize, wheat, rice and sorghum is highly prevalent with each commodity accounting for more than 10% of world’s AF exposure. Their occurrence as food contaminants is also associated with huge economic losses. AFs are highly stable compounds that cannot be eliminated by regular processing of grains. Hence, prevention of AFs in food and feed is now considered more important than the subsequent interventions to mitigate the deleterious health effects of AFs in human and animals. However, the development of an effective preventive strategy hinges on a clear understanding of the underlying factors influencing AFs production. Therefore, the present review aims to highlight the most significant factors influencing AFs contamination of cereals at pre-and post-harvest stages. This is crucial for effective monitoring of critical control points and optimisation of preventive strategies in food and feed supply chains. Several intrinsic and extrinsic factors have been reported of which nutritional composition, environmental factors (temperature, water activity and relative humidity) and climate change have been identified as primary factors, while pH of the substrate, carbon dioxide (CO2) levels in the gaseous environment, and agronomic and socioeconomic status are the main secondary factors promoting AFs biosynthesis in cereals. Additionally, an overview of global occurrence of AFs in cereals, with their health impacts and various preventive measures have also been highlighted.

Aflatoxins in food: Prevalence, health effects, and emerging trends in its mitigation—An updated review

“…GAPs and GMPs create the first line of impactful defense against AF contamination in the food products. Along with crop rotation which could be highly effective in breaking the cycles of toxin‐producing microorganisms (Achaglinkame et al., 2017), timely planting (preferably resistant varieties) and harvesting, good tillage/weeding processes, and proper sanitation and cleaning, have been shown to reduce the infestation of fungal contaminations and released toxins (Achaglinkame et al., 2017; Bhardwaj et al., 2022). The use of fungicides and insecticides or their antagonists, “generally recognized as safe” such as vanilline (3‐methoxysalicylaldehyde) and 2‐hydroxy‐4‐methoxybenzaldehyde, have also been shown to inhibit the fungal growth and their mycotoxins (Kabar et al., 2006; Li & Zhu, 2021).…”

“…Preharvest techniques focus on fungal contamination in the field, whereas postharvest approaches focus on sorting and proper storage (Pankaj et al., 2018). Preharvest mitigation techniques such as Good Agricultural Practises (GAPs), Good Manufacturing Practises (GMPs), biocontrol, and development of resistant crop varieties have proven effective in AF prevention (Bhardwaj et al., 2022). Postharvest management plays an important role in mycotoxin mitigation by ensuring good grain food chain management during harvesting, cleaning, drying, storage, and processing (Leslie et al., 2021).…”

Antifungal Effect of Autochthonous Aromatic Plant Extracts on Two Mycotoxigenic Strains of Aspergillus flavus

“…They can be both acutely and chronically toxic and be carcinogenic, mutagenic, teratogenic and immunosuppressive to most mammalian species [13,14]. Aflatoxins have been detected in many foods, but their presence is especially important in maize, cottonseeds, peanuts and other nuts [15,16]. Conventional chemical and physical methods are insufficient to remove toxins from foods, and the use of synthetic compounds to inhibit mold growth can lead to resistance and health problems [17].…”