Retrospective and Prospective Look at Aflatoxin Research and Development from a Practical Standpoint

Advances, challenges, and opportunities for food safety analysis in the isothermal nucleic acid amplification/CRISPR-Cas12a era

Global food safety stands out as a prominent public concern, affecting populations worldwide. The recurrent challenge of food safety incidents reveals the need for a robust inspection framework. In recent years, the integration of isothermal nucleic acid amplification with CRISPR-Cas12a techniques has emerged as a promising tool for molecular detection of food hazards, presenting next generation of biosensing for food safety detection. This paper provides a comprehensive review of the current state of research on the synergistic application of isothermal nucleic acid amplification and CRISPR-Cas12a technology in the field of food safety. This innovative combination not only enriches the analytical tools, but also improving assay performance such as sensitivity and specificity, addressing the limitations of traditional methods. The review summarized various detection methodologies by the integration of isothermal nucleic acid amplification and CRISPR-Cas12a technology for diverse food safety concerns, including pathogenic bacterium, viruses, mycotoxins, food adulteration, and genetically modified foods. Each section elucidates the specific strategies employed and highlights the advantages conferred. Furthermore, the paper discussed the challenges faced by this technology in the context of food safety, offering insightful discussions on potential solutions and future prospects.

Effects of enhance recovery after surgery nursing program on the surgical site wound infection in patients undergoing laparoscopic hepatectomy for hepatocellular carcinoma: A meta-analysis

Our study aimed to investigate the effects of an enhanced recovery after surgery (ERAS) nursing program on surgical site wound infections (SSWI) and postoperative complications in patients undergoing laparoscopic hepatectomy (LH) for hepatocellular carcinoma. Computer searches of the PubMed, Cochrane Library, Web of Science, Embase, China National Knowledge Infrastructure and Wanfang databases were conducted to gather randomised controlled trials (RCTs) that were published from inception to September 2023. The target studies evaluated the effects of the ERAS nursing program in patients undergoing LH for hepatocellular carcinoma. Two independent authors screened the literature, extracted the data and performed quality assessments. Dichotomous variables were analysed using odds ratios (ORs) and 95% confidence intervals (CIs), as effect analysis statistics. Stata software (version 17.0) was used for data analysis. Eleven RCTs with 765 patients were included, with 383 patients in the ERAS group and 382 in the control group. The results revealed that the incidence of SSWI (OR = 0.32, 95%CI:0.15-0.71, p = 0.004) and postoperative complications (OR = 0.23, 95%CI:0.15-0.34, p < 0.001) were both significantly reduced in the ERAS group, compared with the control group. The ERAS nursing program, when applied to patients undergoing laparoscopic hepatic cancer resection, can effectively reduce the incidence of SSWI and postoperative complications, thus promoting postoperative recovery.

Lipidomic profiling study on neurobehavior toxicity in zebrafish treated with aflatoxin B1

Mycotoxin aflatoxin B1 (AFB1) has been proven to cause neurotoxicity, but its potential interference with the normal function of brain tissue is not fully defined. As the indispensable role of lipids in maintaining the normal function of brain tissue, the aim of this study is to clarify the effect of AFB1 short-term (7 days) exposure on brain tissue from the perspective of lipid metabolism. In this study, zebrafish were exposed to two concentrations (5, 20 μg/L). Through quantitative analysis of AFB1, the detection of AFB1 in zebrafish brain tissue was discovered for the first time, combined with the changes in zebrafish neurobehavior, the occurrence of brain injury was deduced. Subsequently, 1734 lipids in zebrafish brain tissue were mapped using ion mobility time-of-flight mass spectrometry (UPLC-QTOF-IMS-MS), which has great advantages in lipid detection. Comparative analysis of the abnormal lipid metabolism in zebrafish brain revealed 114 significantly changed lipids, mainly involving two pathways of sphingolipid metabolism and fatty acid degradation. This study discovered the detection of AFB1 in the brain and revealed a potential link between AFB1-induced behavioral abnormalities and lipid metabolism disorders in brain tissue, providing reliable evidence for elucidating the neurotoxicity of AFB1.

Research update on aflatoxins toxicity, metabolism, distribution, and detection: A concise overview

Serious health risks associated with the consumption of food products contaminated with aflatoxins (AFs) are worldwide recognized and depend predominantly on consumed AF concentration by diet. A low concentration of aflatoxins in cereals and related food commodities is unavoidable, especially in subtropic and tropic regions. Accordingly, risk assessment guidelines established by regulatory bodies in different countries help in the prevention of aflatoxin intoxication and the protection of public health. By assessing the maximal levels of aflatoxins in food products which are a potential risk to human health, it's possible to establish appropriate risk management strategies. Regarding, a few factors are crucial for making a rational risk management decision, such as toxicological profile, adequate information concerning the exposure duration, availability of routine and some novel analytical techniques, socioeconomic factors, food intake patterns, and maximal allowed levels of each aflatoxin in different food products which may be varied between countries.

Extensive Evaluation of a Method for Quantitative Measurement of Aflatoxins B1 and M1 in Animal Urine Using High-Performance Liquid Chromatography with Fluorescence Detection

BACKGROUND

Aflatoxins (AFs) are common feed contaminants and are one of the common causes of toxin-related pet food poisoning and recalls.

OBJECTIVE

Currently, there are no validated methods for the detection and quantitation of AFs in biological matrices to diagnose AF exposure in live animals. Following a successful intra-laboratory method development to quantify AFB1 and AFM1 in animal urine by HPLC with fluorescence detection (HPLC-FLD), the present study was conducted to extensively evaluate the method performance in an unbiased manner using blinded samples.

METHODS

The evaluation included two stages. First, the performance was verified in the method-originating laboratory in a single-laboratory blinded method test (BMT-S) trial followed by a multi-laboratory blinded method test (BMT-M) trial.

RESULTS

In both trials, accuracy, repeatability, and reproducibility were satisfactory confirming the relatively good ruggedness and robustness of the method and ensuring that it will perform as expected if used by other laboratories in the future.

CONCLUSIONS

We extensively evaluated the performance of a quantitative method to detect AFB1 and AFM1 in animal urine by HPLC-FLD by two different laboratories in two separate BMT-S and BMT-M trials. Both BMT results demonstrated the satisfactory accuracy and precision of the method. It is now available to be adopted by other diagnostic laboratories for purposes of diagnosing AF intoxication in animals.

HIGHLIGHTS

A simple urine-based diagnostic test method using HPLC-FLD that originated in a single laboratory now has passed a multi-laboratory evaluation and is now available to be shared with other diagnostic laboratories for purposes of diagnosing AF intoxication in animals so better treatment can be rendered.

Human Breast Milk Contamination with Aflatoxins, Impact on Children's Health, and Possible Control Means: A Review

Aflatoxins are natural toxicants produced mainly by species of the Aspergillus genus, which contaminate virtually all feeds and foods. Apart from their deleterious health effects on humans and animals, they can be secreted unmodified or carried over into the milk of lactating females, thereby posing health risks to suckling babies. Aflatoxin M1 (AFM1) is the major and most toxic aflatoxin type after aflatoxin B1 (AFB1). It contaminates human breast milk upon direct ingestion from dairy products or by carry-over from the parent molecule (AFB1), which is hydroxylated in the liver and possibly in the mammary glands by cytochrome oxidase enzymes and then excreted into breast milk as AFM1 during lactation via the mammary alveolar epithelial cells. This puts suckling infants and children fed on this milk at a high risk, especially that their detoxifying activities are still weak at this age essentially due to immature liver as the main organ responsible for the detoxification of xenobiotics. The occurrence of AFM1 at toxic levels in human breast milk and associated health conditions in nursing children is well documented, with developing countries being the most affected. Different studies have demonstrated that contamination of human breast milk with AFM1 represents a real public health issue, which should be promptly and properly addressed to reduce its incidence. To this end, different actions have been suggested, including a wider and proper implementation of regulatory measures, not only for breast milk but also for foods and feeds as the upstream sources for breast milk contamination with AFM1. The promotion of awareness of lactating mothers through the organization of training sessions and mass media disclosures before and after parturition is of a paramount importance for the success of any action. This is especially relevant that there are no possible control measures to ensure compliance of lactating mothers to specific regulatory measures, which can yet be appropriate for the expansion of breast milk banks in industrialized countries and emergence of breast milk sellers. This review attempted to revisit the public health issues raised by mother milk contamination with AFM1, which remains undermined despite the numerous relevant publications highlighting the needs to tackle its incidence as a protective measure for the children physical and mental health.

Aflatoxins in Cereals and Cereal-Based Products: Occurrence, Toxicity, Impact on Human Health, and Their Detoxification and Management Strategies

Cereals and cereal-based products are primary sources of nutrition across the world. However, contamination of these foods with aflatoxins (AFs), secondary metabolites produced by several fungal species, has raised serious concerns. AF generation in innate substrates is influenced by several parameters, including the substrate type, fungus species, moisture content, minerals, humidity, temperature, and physical injury to the kernels. Consumption of AF-contaminated cereals and cereal-based products can lead to both acute and chronic health issues related to physical and mental maturity, reproduction, and the nervous system. Therefore, the precise detection methods, detoxification, and management strategies of AFs in cereal and cereal-based products are crucial for food safety as well as consumer health. Hence, this review provides a brief overview of the occurrence, chemical characteristics, biosynthetic processes, health hazards, and detection techniques of AFs, along with a focus on detoxification and management strategies that could be implemented for food safety and security.

Role of Climate Change in Changing Hepatic Health Maps

PURPOSE OF REVIEW

Climate change (CC) is currently responsible for global weather extremes. These weather extremes could contribute to changes in the pattern of health problems. The purpose of this review is to discuss the role of CC on remapping of hepatic diseases and the mechanisms of re-mapping.

RECENT FINDINGS

CC was found to have a major influence on the distribution and severity of hepatic diseases, such as outbreaks of vector-borne, water or food-borne, parasitic diseases, re-emerging of disappeared diseases, or emerging of new forms of infectious agents. Migration of infected people from endemic areas due to the CC disasters results in rapid dissemination of infectious diseases that leads to outbreaks or endemicity of diseases in new areas. CC could cause increasing chemical emissions, or change in its biodegradability, or restriction in its dispersion, such as PM, PAHs, heavy metals, mycotoxins, and aquatic toxins. Increase in the concentrations of these chemicals may have significant impacts in changing the health map of hepatic toxicity and liver cancer. The current review confirms the role of CC in changing the pattern of several liver health problems and remapping of these problems in several regions of the world. This review could be of high importance to the health decision-makers as an early alarm and prediction of hepatic health problems with the projected CC.

Caffeic acid mitigates aflatoxin B1-mediated toxicity in the male rat reproductive system by modulating inflammatory and apoptotic responses, testicular function, and the redox-regulatory systems

Aflatoxin B1 (AFB₁ ) is a toxic metabolite of public health concern. The present study investigates the protective effects of caffeic acid (CA) against AFB₁ -induced oxidative stress, inflammation, and apoptosis in the hypothalamus, epididymis, and testis of male rats. Five experimental rat cohorts (n = 6) were treated per os for 28 consecutive days as follows: Control (Corn oil 2 ml/kg body weight), AFB1 alone (50μg/kg), CA alone (40 mg/kg) and the co-treated rat cohorts (AFB₁ : 50μg/kg + CA1: 20 or 40 mg/kg). Following sacrifice, the biomarkers of hypothalamic, epididymal, and testicular toxicities, antioxidant enzyme activities, myeloperoxidase (MPO) activity, as well as levels of nitric oxide (NO), reactive oxygen and nitrogen (RONS) species and lipid peroxidation (LPO) were analysed spectrophotometrically. Besides, the concentration of tumour necrosis factor-alpha (TNF-α), Bcl-2 and Bax proteins were assessed using ELISA. Results showed that the AFB₁ -induced decrease in biomarkers of testicular, epididymal and hypothalamic toxicity was significantly (p < .05) alleviated in rats coexposed to CA. Moreover, the reduction of antioxidant status and the increase in RONS and LPO were lessened (p < .05) in rats co-treated with CA. AFB₁ mediated increase in TNF-α, Bax, NO and MPO activity were reduced (p< .05) in the hypothalamus, epididymis, and testis of rats coexposed to CA. In addition, Bcl-2 levels were reduced in rats treated with CA dose-dependently. Light microscopic examination showed that histopathological lesions severity induced by AFB₁ were alleviated in rats coexposed to CA. Taken together, the amelioration of AFB₁ -induced neuronal and reproductive toxicities by CA involves anti-inflammatory, antioxidant, antiapoptotic mechanisms in rats. PRACTICAL APPLICATIONS: The beneficial antioxidant effects of caffeic acid (CA) are attributed to CA delocalized aromatic rings and free electrons, easily donated to stabilize reactive oxygen species. We report in vivo findings on CA and AfB1 mediated oxidative stress and reproductive dysfunction in rats. CA conjugated esters including chlorogenic acids are widely distributed in plants, and they act as a dietary source of natural defense against infections. CA can chelate heavy metals and reduce production of damaging free radicals to cellular macromolecules. Along these lines, CA can stabilize aflatoxin B1-epoxide as well and avert deleterious conjugates from forming with deoxyribonucleic acids. Hence CA, as a dietary phytochemical can protect against the damaging effects of toxins including aflatoxin B1 that contaminate food. CA dose-dependently abated oxidative, inflammatory, and apoptotic stimuli, improved functional characteristics of spermatozoa and reproductive hormone levels, and prevented histological alterations in experimental rats' hypothalamus and reproductive organs brought about by AFB1 toxicity.

Omics in the detection and identification of biosynthetic pathways related to mycotoxin synthesis

Mycotoxins are secondary metabolites that are known to be toxic to humans and animals. On the other hand, some mycotoxins and their analogues possess antioxidant as well as antitumor properties, which could be relevant in the fields of pharmaceutical analysis and food research. Omics techniques are a group of analytical tools applied in the biological sciences in order to study genes (genomics), mRNA (transcriptomics), proteins (proteomics), and metabolites (metabolomics). Omics have become a vital tool in the field of mycotoxins, especially contributing to the identification of biomarkers with potential use for the detection of mycotoxigenic species and the gathering of information about the biosynthetic pathways of mycotoxins in different environments. This approach has provided tools for the development of prevention strategies and control measures for different mycotoxins. Additionally, research has revealed important information about the impact of global warming and climate change on the prevalence of mycotoxin issues in society. In the context of foodomics, the aim is to apply omics techniques in order to ensure food safety. The objective of the present review is to determine the state of the art regarding the development of analytical techniques based on omics in the identification of biosynthetic pathways related to mycotoxin synthesis.

Aflatoxin Biosynthesis, Genetic Regulation, Toxicity, and Control Strategies: A Review

Aflatoxins (AFs) are highly toxic and cancer-causing compounds, predominantly synthesized by the Aspergillus species. AFs biosynthesis is a lengthy process that requires as minimum as 30 genes grouped inside 75 kilobytes (kB) of gene clusters, which are regulated by specific transcription factors, including aflR, aflS, and some general transcription factors. This paper summarizes the status of research on characterizing structural and regulatory genes associated with AF production and their roles in aflatoxigenic fungi, particularly Aspergillus flavus and A. parasiticus, and enhances the current understanding of AFs that adversely affect humans and animals with a great emphasis on toxicity and preventive methods.

Aflatoxins: History, Significant Milestones, Recent Data on Their Toxicity and Ways to Mitigation

In the early 1960s the discovery of aflatoxins began when a total of 100,000 turkey poults died by hitherto unknown turkey "X" disease in England. The disease was associated with Brazilian groundnut meal affected by Aspergillus flavus. The toxin was named Aspergillus flavus toxin-aflatoxin. From the point of view of agriculture, aflatoxins show the utmost importance. Until now, a total of 20 aflatoxins have been described, with B1, B2, G1, and G2 aflatoxins being the most significant. Contamination by aflatoxins is a global health problem. Aflatoxins pose acutely toxic, teratogenic, immunosuppressive, carcinogenic, and teratogenic effects. Besides food insecurity and human health, aflatoxins affect humanity at different levels, such as social, economical, and political. Great emphasis is placed on aflatoxin mitigation using biocontrol methods. Thus, this review is focused on aflatoxins in terms of historical development, the principal milestones of aflatoxin research, and recent data on their toxicity and different ways of mitigation.

Predicted Aflatoxin B1 Increase in Europe Due to Climate Change: Actions and Reactions at Global Level

Climate change (CC) is predicted to increase the risk of aflatoxin (AF) contamination in maize, as highlighted by a project supported by EFSA in 2009. We performed a comprehensive literature search using the Scopus search engine to extract peer-reviewed studies citing this study. A total of 224 papers were identified after step I filtering (187 + 37), while step II filtering identified 25 of these papers for quantitative analysis. The unselected papers (199) were categorized as “actions” because they provided a sounding board for the expected impact of CC on AFB₁ contamination, without adding new data on the topic. The remaining papers were considered as “reactions” of the scientific community because they went a step further in their data and ideas. Interesting statements taken from the “reactions” could be summarized with the following keywords: Chain and multi-actor approach, intersectoral and multidisciplinary, resilience, human and animal health, and global vision. In addition, fields meriting increased research efforts were summarized as the improvement of predictive modeling; extension to different crops and geographic areas; and the impact of CC on fungi and mycotoxin co-occurrence, both in crops and their value chains, up to consumers.

The Scourge of Aflatoxins in Kenya: A 60-Year Review (1960 to 2020)

Aflatoxins are endemic in Kenya. The 2004 outbreak of acute aflatoxicosis in the country was one of the unprecedented epidemics of human aflatoxin poisoning recorded in mycotoxin history. In this study, an elaborate review was performed to synthesize Kenya’s major findings in relation to aflatoxins, their prevalence, detection, quantification, exposure assessment, prevention, and management in various matrices. Data retrieved indicate that the toxins are primarily biosynthesized by Aspergillus flavus and A. parasiticus, with the eastern part of the country reportedly more aflatoxin-prone. Aflatoxins have been reported in maize and maize products (Busaa, chan’gaa, githeri, irio, muthokoi, uji, and ugali), peanuts and its products, rice, cassava, sorghum, millet, yams, beers, dried fish, animal feeds, dairy and herbal products, and sometimes in tandem with other mycotoxins. The highest total aflatoxin concentration of 58,000 μg/kg has been reported in maize. At least 500 acute human illnesses and 200 deaths due to aflatoxins have been reported. The causes and prevalence of aflatoxins have been grossly ascribed to poor agronomic practices, low education levels, and inadequate statutory regulation and sensitization. Low diet diversity has aggravated exposure to aflatoxins in Kenya because maize as a dietetic staple is aflatoxin-prone. Detection and surveillance are only barely adequate, though some exposure assessments have been conducted. There is a need to widen diet diversity as a measure of reducing exposure due to consumption of aflatoxin-contaminated foods.

Liver cancer mortality over six decades in an epidemic area: what we have learned

Background and aims:

Liver cancer is one of the most dominant malignant tumors in the world. The trends of liver cancer mortality over the past six decades have been tracked in the epidemic region of Qidong, China. Using epidemiological tools, we explore the dynamic changes in age-standardized rates to characterize important aspects of liver cancer etiology and prevention.

Methods

Mortality data of liver cancer in Qidong from 1958 to 1971 (death retrospective survey) and from 1972 to 2017 (cancer registration) were tabulated for the crude rate (CR), and age-standardized rate and age-birth cohorts. The average annual percentage change was calculated by the Joinpoint Regression Program.

Results

The natural death rate during 1958–2017 decreased from 9‰ to 5.4‰ and then increased to 8‰ as the population aged; cancer mortality rates rose continuously from 57/10⁵ to 240/10⁵. Liver cancer mortality increased from 20/10⁵ to 80/10⁵, and then dropped to less than 52/10⁵ in 2017. Liver cancer deaths in 1972–2017 accounted for 30.53% of all cancers, with a CR of 60.48/10⁵, age-standardized rate China (ASRC) of 34.78/10⁵, and ASRW (world) of 45.71/10⁵. Other key features were the CR for males and females of 91.86/10⁵ and 29.92/10⁵, respectively, with a sex ratio of 3.07:1. Period analysis showed that the ASRs for mortality of the age groups under 54 years old had a significant decreasing trend. Importantly, birth cohort analysis showed that the mortality rate of liver cancer in 40–44, 35–39, 30–34, 25–29, 20–24, 15–19 years cohort decreased considerably, but the rates in 70–74, and 75+ increased.

Conclusions

The crude mortality rate of liver cancer in Qidong has experienced trends from lower to higher levels, and from continued increase at a high plateau to most recently a gradual decline, and a change greatest in younger people. Many years of comprehensive prevention and intervention measures have influenced the decline of the liver cancer epidemic in this area. The reduction of intake levels of aflatoxin might be one of the most significant factors as evidenced by the dramatic decline of exposure biomarkers in this population during the past three decades.

Inhibition analysis of aflatoxin by in silico targeting the thioesterase domain of polyketide synthase enzyme in Aspergillus ssp

The spread of fungal growth causes enormous economic, agricultural, and health problems for humans, such as Aspergillus sp., which produce aflatoxins. Thus, the inhibition of aflatoxin production became a precious target. In this research, the thioesterase (TE) domain from Polyketide synthase enzyme was selected to employ the in silico docking, using AutoDock Vina, against 623 natural compounds from the South African natural compound database (SANCDB), to identify potential inhibitors that can selectively inhibit thioesterase domain. The top ten inhibitors components were pinocembrin, typhaphthalide, p-coumaroylputrescine, dilemmaone A, 9-angelylplatynecine, 2,4,6-octatrienal, 4,8-dichloro-3,7-dimethyl-, (2e,4z,6e)-, lilacinobiose, 1,3,7-octatriene, 5,6-dichloro-2-(dichloromethyl)-6-methyl-, [r*,s*-(e)]-(-)- (9ci), lilacinobiose, 1,3,7-octatriene, 5,6-dichloro-2-(dichloromethyl)-6-methyl-, [r*,s*-(e)]-(-)- (9ci), 1,3,7-octatriene, 1,5,6-trichloro-2-(dichloromethyl)-6-methyl-, [r*,s*-(z,e)] and 9-angelylhastanecine and that depending on the lowest binding energy, the best chemical interactions and the best drug-likeness. The results of those components gave successful inhibition with the thioesterase domain. So, they can be used for inhibition and controlling aflatoxin contamination of agriculture crop yields, specially, pinocembrin which gave promising results.Communicated by Ramaswamy H. Sarma.

Amelioration of pulmonary aflatoxicosis by green tea extract: An in vivo study

Aflatoxins (AFB₁) are mycotoxins known to be associated with human and animal diseases. The lung is a at risk from AFB₁exposure either via inhalation or circulation. Green tea consumption is increasing over time due to widespread popularity as antioxidants, anti-inflammatory, and cytoprotective agents. Therefore, we attempted to study the lung toxicity caused by AFB₁ and the possible ameliorating effect of green tea extract. Forty adult male albino rats were divided into five groups; Group I: Untreated control group, Group II (vehicle): Each rat received 1 ml of olive oil, Group III (GTE): Each rat received Camellia sinensis, green tea extract (30 mg/kg/day), Group IV(AFB₁): Each rat received (50 μg/kg/day of AFB₁). Group V (AFB₁+ GTE): Each rat received the same previously mentioned doses of AFB1 in addition to GTE concomitantly. All treatments were orally gavaged for 8 weeks then rats were sacrificed. Serum levels of pro-inflammatory (IL-1β, TNF-α, IL-6) and anti-inflammatory (IL-10) cytokines were measured, lung tissues' oxidative stress indices were also measured in addition to the histopathological study which was performed by using hematoxylin & eosin and Masson trichrome stains. Morphometric and statistical analyses were also performed. Oral gavage of AFB₁ resulted in significant histopathological changes in the lung tissues, in the form of variable degrees of congestion, hemorrhage, interstitial inflammation with infiltration by chronic inflammatory cells, interstitial fibrosis, bronchitis, vasculitis and fibrous thickening of arterial walls. Inflammation was evident by elevated levels of pro-inflammatory cytokines and a declined level of anti-inflammatory cytokines. Also, oxidative stress was evident by increased levels of Malondialdehyde (MDA), Myeloperoxidase (MPO), and decreased levels of total glutathione (tGSH) and Catalase (CAT). The histopathological changes, inflammatory cytokines, and oxidative stress markers were significantly decreased during concomitant administration of green tea extract in (AFB₁+ GTE) group. Aflatoxin B₁ has deleterious effects on the lung tissue that could be minimized by concomitant administration of Green tea extract owing to its anti-inflammatory, antioxidant, and protective properties.

Detoxification of Aflatoxin B1 Contaminated Maize Using Human CYP3A4

Aflatoxin B1 (AFB1) is a mycotoxin produced by Aspergillus flavus (A. flavus). AFB1 is reported to have high thermal stability and is not decomposed by heat treatment during food processing. Therefore, in this study, knowing that AFB1 is metabolized by cytochrome P450 (CYP), our aim was to develop a method to detoxify A. flavus-contaminated maize, under normal temperature and pressure, using Escherichia coli expressing human CYP3A4. First, the metabolic activity of AFB1 by recombinant human CYP3A4 was evaluated. As a result, we confirmed that recombinant human CYP3A4 metabolizes 98% of AFB1. Next, we found that aflatoxin Q1, a metabolite of AFB1 was no longer mutagenic. Furthermore, we revealed that about 50% of the AFB1 metabolic activity can be maintained for 3 months when E. coli expressing human CYP3A4 is freeze-dried in the presence of trehalose. Finally, we found that 80% of AFB1 in A. flavus-contaminated maize was metabolized by E. coli expressing human CYP3A4 in the presence of surfactant triton X-405 at a final concentration of 10% (v/v). From these results, we conclude that AFB1 in A. flavus-contaminated maize can be detoxified under normal temperature and pressure by using E. coli expressing human CYP3A4.

Gallic acid protects against Aflatoxin B1 -induced oxidative and inflammatory stress damage in rats kidneys and liver

The adverse effect of Aflatoxin B1 (AFB₁ ) exposure in both humans and rodents has been widely reported. The beneficial health effects of gallic acid (GA) against AFB₁ -induced toxicity in vitro have been published. Here, we present in vivo findings on AFB₁ and GA on hepatorenal function in rats, exposed to AFB₁ (75 µg/kg body weight) only or co-treated with GA (20 or 40 mg/kg) for 28 successive days. AFB₁ significantly increased pro-inflammatory biomarkers and suppressed IL-10 levels in rats' liver and kidney. AFB₁ caused increased (p < .05) oxidative stress by decreasing antioxidant enzymes levels and increasing levels of reactive oxygen and nitrogen species. Furthermore, reduction (p < .05) in cellular glutathione (GSH) levels and increased (p < .05) hepatorenal markers of toxicity were detected in rats treated with AFB₁ . These observed alterations were, however, reversed in GA co-treated rats. GA ameliorated AFB₁ -induced hepatorenal dysfunction by decreasing oxidative stress and inflammation in rats. PRACTICAL APPLICATIONS: GA can chemoprotect against the damaging effects of toxins contaminating food. GA is widely distributed in plants and in use in industries as antioxidant, immune-regulator, and natural defense agent against infections when consumed. Here, we disclosed that GA ameliorates AFB₁ -induced hepatorenal dysfunction by suppressing oxidative stress, inflammation, and enhanced apoptosis, thus improving hepatorenal functions in rats exposed to AFB_1.

Characteristics, Occurrence, Detection and Detoxification of Aflatoxins in Foods and Feeds

Mycotoxin contamination continues to be a food safety concern globally, with the most toxic being aflatoxins. On-farm aflatoxins, during food transit or storage, directly or indirectly result in the contamination of foods, which affects the liver, immune system and reproduction after infiltration into human beings and animals. There are numerous reports on aflatoxins focusing on achieving appropriate methods for quantification, precise detection and control in order to ensure consumer safety. In 2012, the International Agency for Research on Cancer (IARC) classified aflatoxins B1, B2, G1, G2, M1 and M2 as group 1 carcinogenic substances, which are a global human health concern. Consequently, this review article addresses aflatoxin chemical properties and biosynthetic processes; aflatoxin contamination in foods and feeds; health effects in human beings and animals due to aflatoxin exposure, as well as aflatoxin detection and detoxification methods.

Bioactive compounds from Aspergillus niger extract enhance the antioxidant activity and prevent the genotoxicity in aflatoxin B1-treated rats

This study aimed to identify the bioactive compounds of the ethyl acetate extract of Aspergillus niger SH2-EGY using GC-MS and to evaluate their protective role against aflatoxin B₁ (AFB₁)-induced oxidative stress, genotoxicity and cytotoxicity in rats. Six groups of male Sprague-Dawley rats were treated orally for 4 weeks included the control group, AFB₁-treated group (80 μg/kg b.w); fungal extract (FE)-treated groups at low (140) or high dose (280) mg/kg b.w and the groups treated with AFB₁ plus FE at the two tested doses. The GC-MS analysis identified 26 compounds. The major compounds found were 1,2,3,4,6-Penta-trimethylsilyl Glucopyranose, Fmoc-L-3-(2-Naphthyl)-alanine, D-(-)-Fructopyranose, pentakis (trimethylsilyl) ether, bis (2-ethylhexyl) phthalate, trimethylsilyl ether-glucitol, and octadecanamide, N-(2- methylpropyl)-N-nitroso. The in vivo results showed that AFB₁ significantly increased serum ALT, AST, creatinine, uric acid, urea, cholesterol, triglycerides, LDL, carcinoembryonic antigen, alpha-fetoprotein, interleukin-6, Malondialdehyde, nitric oxide, Bax, caspase-3 and P53 mRNA expression, chromosomal aberrations and DNA fragmentation. It decreased serum TP, albumin, HDL, Bcl-2 mRNA expression, hepatic and renal TAC, SOD and GPx content and induced histological changes in the liver and kidney. FE prevented these disturbances in a dosage-dependent manner. It could be concluded that A. niger SH2-EGY extract is safe a promising agent for pharmaceutical and food industries.

Aflatoxins: Producing-Molds, Structure, Health Issues and Incidence in Southeast Asian and Sub-Saharan African Countries

This review aims to update the main aspects of aflatoxin production, occurrence and incidence in selected countries, and associated aflatoxicosis outbreaks. Means to reduce aflatoxin incidence in crops were also presented, with an emphasis on the environmentally-friendly technology using atoxigenic strains of Aspergillus flavus. Aflatoxins are unavoidable widespread natural contaminants of foods and feeds with serious impacts on health, agricultural and livestock productivity, and food safety. They are secondary metabolites produced by Aspergillus species distributed on three main sections of the genus (section Flavi, section Ochraceorosei, and section Nidulantes). Poor economic status of a country exacerbates the risk and the extent of crop contamination due to faulty storage conditions that are usually suitable for mold growth and mycotoxin production: temperature of 22 to 29 °C and water activity of 0.90 to 0.99. This situation paralleled the prevalence of high liver cancer and the occasional acute aflatoxicosis episodes that have been associated with these regions. Risk assessment studies revealed that Southeast Asian (SEA) and Sub-Saharan African (SSA) countries remain at high risk and that, apart from the regulatory standards revision to be more restrictive, other actions to prevent or decontaminate crops are to be taken for adequate public health protection. Indeed, a review of publications on the incidence of aflatoxins in selected foods and feeds from countries whose crops are classically known for their highest contamination with aflatoxins, reveals that despite the intensive efforts made to reduce such an incidence, there has been no clear tendency, with the possible exception of South Africa, towards sustained improvements. Nonetheless, a global risk assessment of the new situation regarding crop contamination with aflatoxins by international organizations with the required expertise is suggested to appraise where we stand presently.

Chronic and Acute Toxicities of Aflatoxins: Mechanisms of Action

There are presently more than 18 known aflatoxins most of which have been insufficiently studied for their incidence, health-risk, and mechanisms of toxicity to allow effective intervention and control means that would significantly and sustainably reduce their incidence and adverse effects on health and economy. Among these, aflatoxin B1 (AFB1) has been by far the most studied; yet, many aspects of the range and mechanisms of the diseases it causes remain to be elucidated. Its mutagenicity, tumorigenicity, and carcinogenicity-which are the best known-still suffer from limitations regarding the relative contribution of the oxidative stress and the reactive epoxide derivative (Aflatoxin-exo 8,9-epoxide) in the induction of the diseases, as well as its metabolic and synthesis pathways. Additionally, despite the well-established additive effects for carcinogenicity between AFB1 and other risk factors, e.g., hepatitis viruses B and C, and the hepatotoxic algal microcystins, the mechanisms of this synergy remain unclear. This study reviews the most recent advances in the field of the mechanisms of toxicity of aflatoxins and the adverse health effects that they cause in humans and animals.