Search Results (53)

Background/Objectives: Ellagic acid (EA) is a polyphenol found in several fruits and vegetables, including pomegranate, nuts and berries. It exhibits significant health benefits, mainly cardio- and vaso-protective; indeed, EA protects the myocardium against infarction and inhibits cardiac fibrosis. These beneficial effects may be, at least in part, promoted by calcium release from and uptake by the sarcoplasmic reticulum, which are crucial events for cardiac relaxation and contraction. Regardless, the exact mechanism is currently unclear. Methods: A deeper investigation of the role of EA in cardiac contractility and the underlying mechanism has been carried out by using an ex vivo model of isolated and perfused rat heart. Results and Discussion: EA perfusion (100 nM–10 µM) did not influence the coronary flow (CF), suggesting the absence of a vasoactivity, but significantly increased contractility parameters (LVDP and dP/dt). Interestingly, a more marked effect of EA on LVDP and dP/dt values was observed when it was perfused in the presence of AngII. Cyclopiazonic acid (CA) and red ruthenium (RR), specific antagonists of SERCA and RyRs, respectively, were used to explore the contribution of EA when the intracellular calcium handling was altered. In the presence of CA, EA, perfused at increasing concentrations, showed a very modest positive inotropism (significant only at 1 µM). Instead, RR, which significantly compromised all functional parameters, completely masked the effects of EA; furthermore, a marked reduction in CF and a dramatic impact on the positive inotropism occurred. Conclusions: These results demonstrate the positive inotropism of EA on isolated and perfused hearts and suggest that the RyRs may be a main target through which EA plays its effects, since inhibition with RR almost completely blocks the positive inotropism. Full article

Aflatoxins, toxic secondary metabolites produced primarily by Aspergillus flavus and Aspergillus parasiticus, pose significant risks to food safety, public health, and global trade. These mycotoxins contaminate staple crops such as maize and peanuts, particularly in warm and humid regions, leading to economic losses and severe health effects, including hepatocellular carcinoma, immune suppression, and growth impairment. In addition to aflatoxins, Aspergillus species produce other toxic metabolites such as ochratoxin A, sterigmatocystin, and cyclopiazonic acid, which are associated with nephrotoxic, carcinogenic, and neurotoxic effects, respectively. This review provides a comprehensive analysis of aflatoxin toxicity, mitigation strategies, and chemical detection methods. The toxicity of aflatoxins is discussed in relation to their biochemical mechanisms, carcinogenicity, and synergistic effects with other mycotoxins. Various mitigation approaches, including pre-harvest biocontrol, post-harvest storage management, and novel detoxification methods such as enzymatic degradation and nanotechnology-based interventions, are evaluated. Furthermore, advances in aflatoxin detection, including chromatographic, immunoassay, and biosensor-based methods, are explored to improve regulatory compliance and food safety monitoring. This review underscores the need for integrated management strategies and global collaboration to reduce aflatoxin contamination and its associated health and economic burdens. Future research directions should focus on genetic engineering for resistant crop varieties, climate adaptation strategies, and improved risk assessment models. Full article

The global increase in chicken meat production and consumption has heightened concerns regarding the safety of chicken meat and its derived products. This study aimed to investigate the presence of Penicillium and Aspergillus mycotoxins in 50 samples of chicken breast muscle and liver collected from the Croatian market. Eight mycotoxins commonly produced by Aspergillus and Penicillium species were analyzed: aflatoxins B₁ (AFB₁), G₁ (AFG₁), B₂ (AFB₂), and G₂ (AFG₂); sterigmatocystin (STC); ochratoxin A (OTA); cyclopiazonic acid (CPA); and citrinin (CIT). Mycotoxin concentrations were determined using liquid chromatography–tandem mass spectrometry (LC-MS/MS) following sample cleanup with immunoaffinity columns while a QuEChERS-based method was applied for CPA. Mycotoxin occurrence was higher in liver samples, indicating the liver as primary site of mycotoxin accumulation compared to muscle tissue, where only CPA was detected. CPA was present in 20% of all samples, with the highest concentration (6.50 µg/kg) found in breast muscle, detected for the first time in fresh meat. AFB₁ and OTA were each detected in 10% of samples, and CIT was found in 4%—all exclusively in liver tissue. Notably, 4 out of the 17 contaminated samples contained more than one mycotoxin. Although the detected concentrations can be considered too low to pose an immediate health risk, the contamination rate suggests further research into these mycotoxins in chicken and other poultry species is needed. Full article

According to the scientific information reviewed, cheese is highly susceptible to contamination by mycotoxin-producing fungi, primarily species from the genera Aspergillus (A. niger, A. flavus) and Penicillium (P. commune, P. solitum, P. palitans, and P. crustosum). Studies on various types of cheese made from cow’s milk report an average concentration of Aflatoxin M1 (AFM₁) at 13,000 ng kg⁻¹, which is alarming since the regulatory limits for AFM₁ in cheese range from 250 to 500 ng kg⁻¹. For instance, limits set by Codex Alimentarius, the European Commission (EC), Turkey, and Iran are 250 ng kg⁻¹. In the Netherlands, the limit is 200 ng kg⁻¹, and in Italy, it is 450 ng kg⁻¹. However, the concentration of mycotoxins frequently exceeds these regulatory limits, including critical mycotoxins such as ochratoxin A, citrinin, and cyclopiazonic acid, which pose significant global health concerns. Therefore, this study aims to review the mycobiota responsible for producing key mycotoxins in cheese and to assess the influence of physicochemical factors on fungal growth and mycotoxin production. By incorporating control strategies such as hygiene practices, pasteurization, and the use of preservatives, this study seeks to improve methodologies in the cheese production chain and mitigate contamination by fungi and mycotoxins. Full article

Kojic acid is a secondary metabolite with strong chelating and antioxidant properties produced by Aspergillus flavus and A. oryzae. Although antioxidants and chelators are important virulence factors for plant pathogens, the ecological role of kojic acid remains unclear. We previously observed a greater gene expression of antioxidants, especially kojic acid, by non-aflatoxigenic A. flavus when co-cultured with aflatoxigenic A. flavus. Aflatoxin production was also reduced. In this study, we investigated kojic acid production in 22 A. flavus isolates from Louisiana and compared them to four common A. flavus strains in liquid medium and on corn kernels. Corn kernel infection was assessed by quantifying the maize beta tubulin DNA content of the kernels using drop digital PCR (ddPCR). Maize beta tubulin DNA content decreased with increased corn kernel infection. Greater kojic acid production by A. flavus isolates coincided with greater levels of corn kernel infection. All isolates produced 60 and 700 times more kojic acid than aflatoxin and cyclopiazonic acid (a known virulence factor), respectively, which varied among sclerotial size categories. A. flavus strains with small sclerotia, which were rarely isolated from corn, produced the least kojic acid and infected corn kernels the least, while medium and large sclerotia strains—mainly isolated from corn—produced the most kojic acid and were more infectious. Non-aflatoxigenic isolates from Louisiana produced the most kojic acid. These results suggest that kojic acid is a potential virulence factor and may increase the pathogenic success of medium and large sclerotia-producing A. flavus, which could ultimately lead to more effective A. flavus biocontrol strains. Further studies are required to determine the effects that kojic acid has on the redox environment during corn infection and how the altered redox environment decreases aflatoxin production. Full article

(1) Background: Food and feed safety legislation does not concern all the mycotoxins generated by Penicillium and Aspergillus spp. Certain mycotoxins, including mycophenolic acid (MPA), cyclopiazonic acid (CPA), penicillic acid (PA), roquefortine C (ROQ C), and gliotoxin (GLI), are regarded as having lower toxicity levels, and hence are not included in food and feed legislation. It is obvious that xenobiotics, including mycotoxins, exert synergistic harmful health effects on human and animal when exposed through food and feed. (2) Methods: The presence of these substances in maize and wheat grown in Albania across two consecutive harvesting seasons was investigated by liquid chromatography and mass spectrometry (LC-MS/MS). (3) Results: The findings indicated the presence of these mycotoxins in maize grain but not in wheat grain. In the 2014 season, they exhibited a higher contamination incidence than in the 2015 season. The most commonly detected mycotoxin was MPA, followed by CPA and ROQ C toxin, while PA and GLI were not detected. The MPA revealed a concentration range of 72.9–3447 μg/kg, with a mean value of 1064 μg/kg. Mycophenolic acid was detected in the maize samples collected during the 2015 season. (4) Conclusions: These findings suggest that focusing the investigation only on “controlled” mycotoxins will not produce a proper risk assessment and may not adequately address the possible harmful impacts of mycotoxins on human and animal health due to mycotoxins’ co-occurrence. Full article

Cyclopiazonic acid (CPA) is an indole-tetramic acid neurotoxin produced by Aspergillus and Penicillium genera present mainly in fruit, cereals and nuts. This study compares the cytotoxicity produced by CPA after 24, 48 and 72 h of exposure using both monolayers and 3D spheroids in human neuroblastoma SH-SY5Y cells. Furthermore, CPA toxicokinetics was evaluated using in silico models. Cytotoxicity increased dose- and time-dependently, as shown by the MTT assay. The lowest CPA IC₅₀ values were found in the monolayer study compared to the 3D spheroids at all exposure times (24 h: 864.01 vs. 1132; 48 h: 437 vs. 1069; 72 h: 392 vs. 567 nM). The CPA exposure on SH-SY5Y spheroid organization and morphology was also studied. Morphological changes, including spheroid disaggregation, were observed after mycotoxin exposure. The in silico methods, SwissADME and admetSAR, were used for short and full ADMEt profiles of CPA. The ADMEt predictive profile shows high gastrointestinal absorption and ability to penetrate the blood–brain barrier. Including in silico studies emphasizes the comprehensive approach to understanding mycotoxin toxicity and risk assessment. By combining in vitro 3D spheroid models with computational simulations, this study aims to provide a holistic perspective on the effects of CPA, enhancing the accuracy and relevance of our findings. Full article

Mold-ripened cheese acquires a distinctive aroma and texture from mold cultures that mature on a fresh cheese wheel. Owing to its high moisture content (a_w = 0.95) and pliability, soft cheese is prone to contamination. Many contaminating mold species are unable to grow at colder temperatures, and the lactic acid produced by the cheese bacteria inhibits further infiltration. Thus, Camembert cheese is generally well protected against contamination by a wide range of species. In this study, cocultures of Penicillium camemberti and widely distributed mycotoxin-producing mold species were incubated on different types of agars, and purchased Camembert samples were deliberately contaminated with mycotoxin-producing mold species capable of growing at both 25 °C and 4 °C. The production of mycotoxins was then monitored by the extraction of the metabolites and their subsequent measurement by means of a liquid chromatography-tandem mass spectrometry (LC-MS/MS) based targeted metabolite profiling approach. The production of cyclopiazonic acid (CPA) was highly dependent on the species cocultivated with Penicillium camemberti, the temperature and the substrate. Contamination of Camembert cheese with Penicillium chrysogenum, Mucor hiemalis, or Penicillium glabrum induced CPA production at 25 °C. Although mold growth on cheese was not always evident on biofilms for certain cultures, except for Penicillium citrinum, which stained the monosaccharide agar yellow, mycotoxins were detected in many agar and cheese samples, as in all monosaccharide agar samples. In conclusion, cheese should be immediately discarded upon the first appearance of mold. Full article

Penicillium spp. occupy many diverse biological niches that include plant pathogens, opportunistic human pathogens, saprophytes, indoor air contaminants, and those selected specifically for industrial applications to produce secondary metabolites and lifesaving antibiotics. Recent phylogenetic studies have established Penicillium fuscoglaucum as a synonym for Penicillium commune, which is an indoor air contaminant and toxin producer and can infect apple fruit during storage. During routine culturing on selective media in the lab, we obtained an isolate of P. fuscoglaucum Pf_T2 and sequenced its genome. The Pf_T2 genome is far superior to available genomic resources for the species. Our assembly exhibits a length of 35.1 Mb, a BUSCO score of 97.9% complete, and consists of five scaffolds/contigs representing the four expected chromosomes. It was determined that the Pf_T2 genome was colinear with a type specimen P. fuscoglaucum and contained a lineage-specific, intact cyclopiazonic acid (CPA) gene cluster. For comparison, a highly virulent postharvest apple pathogen, P. expansum strain TDL 12.1, was included and showed a similar growth pattern in culture to our Pf_T2 isolate but was far more aggressive in apple fruit than P. fuscoglaucum. The genome of Pf_T2 serves as a major improvement over existing resources, has superior annotation, and can inform forthcoming omics-based work and functional genetic studies to probe secondary metabolite production and disparities in aggressiveness during apple fruit decay. Full article

A novel co-bonded octyl and pyridine silica (OPS) sorbent was prepared and applied for the solid phase extraction (SPE) of cyclopiazonic acid (CPA, a type of mycotoxin) in feed and agricultural products for the first time. A simple mixed-ligand one-pot reaction strategy was employed for OPS sorbent preparation. Nitrogen adsorption–desorption measurements, elemental analysis (EI), thermal gravimetric analysis (TGA), and Fourier transform infrared spectroscopy (FT-IR) analysis demonstrated the successful immobilization of octyl and quaternary ammonium groups onto the surface of silica gel. The large specific surface area, high-density functional groups, and mixed-mode anion-exchange characteristics of these silica particles made them the ideal material for the efficient extraction of CPA. Additionally, the OPS sorbents displayed excellent batch-to-batch reproducibility, satisfactory reusability, and low cost. The SPE parameters were optimized to explore the ionic and hydrophobic interactions between CPA and the functional groups, and the ultra-high performance liquid chromatography coupled with triple-quadrupole tandem mass spectrometry (UPLC-MS/MS) parameters were optimized to obtain a desirable extraction efficiency and high sensitivity to CPA. Meanwhile, the OPS sorbent presented a satisfactory extraction selectivity and low matrix effect. Under the optimized conditions, our developed CPA detection method was used to determine CPA level in rice, wheat flour, corn flour, peanut, and feed samples, exhibiting a lower detection limit, better linearity, higher sensitivity, and satisfactory extraction recovery rate than previously reported methods. Therefore, our method can be preferentially used as a method for the detection of CPA in agricultural products and feeds. Full article

Kodo millet, a staple food in North India, is frequently consumed, but its consumption can lead to intoxication and poisoning. Kodo millet is a rich source of nutrition, with anti-oxidant and medicinal properties, and is typically cultivated in dry and semi-arid regions. It is often infected by fungal species rather than bacterial and virus pathogens, causing economic crop loss and adversely affecting grain and fodder yield. Ergot, a parasitic fungal endophyte found in Kodo millet ear heads, can cause poisoning when consumed. Moreover, Kodo millet grains are frequently infested with Aspergillus tamarii Kita, which produces a significant amount of the mycotoxin cyclopiazonic acid (CPA). Cyclopiazonic acid (CPA) is a neurotoxin produced by certain A. flavus and Aspergillus oryzae strains, which produce aflatoxins. Mycotoxicosis outbreaks in humans are not well characterized, and the direct correlation between mycotoxin consumption and toxic effects In Vivo is not well established. CPA, a specific inhibitor of sarcoplasmic reticulum Ca²⁺-ATPase, can adversely affect broiler chicken health, as demonstrated by toxicological evaluation of aflatoxins and CPA alone or in combination. Most toxins have reported acute and chronic effects in prokaryotic and eukaryotic systems, including humans, despite thefact that their specific modes of action are unclear. This review explores fungal pathogens, the toxicity of CPA to animals and humans, both by itself and in combination with other mycotoxins, as well as biocontrol strategies and storage methods for better utilization of Kodo grains post harvest. Full article

The natural product α-cyclopiazonic acid (α-CPA) is a very potent Ca²⁺-ATPase inhibitor. The CPA family of compounds comprise over 80 chemical entities with at least five distinct skeletons. While α-CPA features a canonical 6/5/6/5/5 skeleton, the 6/5/6/5 skeleton is the most prevalent among the CPA family. However, the origin of the unique tetracyclic skeleton remains unknown. The 6/5/6/5-type CPAs may derive from a precursor of acetoacetyl-l-tryptophan (AATrp) generated from a hypothetic thioesterase-like pathway. Alternatively, cleavage of the tetramic acid ring would also result in the formation of the 6/5/6/5 scaffold. Aspergillus oryzae HMP-F28 is a marine sponge-associated filamentous fungus known to produce CPAs that act as primary neurotoxins. To elucidate the origin of this subfamily of CPAs, we performed homologous recombination and genetic engineering experiments on strain HMP-F28. Our results are supportive of the ring cleavage pathway through which the tetracyclic 6/5/6/5-type CPAs are generated from 6/5/6/5/5-type pentacyclic CPAs. Full article

Zea mays var. amylacea and Zea mays var. indurata are maize ecotypes from Paraguay. Aspergillus section Flavi is the main spoilage fungus of maize under storage conditions. Due to its large intraspecific genetic variability, the accurate identification of this fungal taxonomic group is difficult. In the present study, potential mycotoxigenic strains of Aspergillus section Flavi isolated from Z. mays var. indurata and Z. mays var. amylacea that are marketed in the metropolitan region of Asunción were identified by a polyphasic approach. Based on morphological characters, 211 isolates were confirmed to belong to Aspergillus section Flavi. A subset of 92 strains was identified as Aspergillus flavus by mass spectrometry MALDI-TOF and the strains were classified by MALDI-TOF MS into chemotypes based on their aflatoxins and cyclopiazonic acid production. According to the partial sequencing of ITS and CaM genes, a representative subset of 38 A. flavus strains was confirmed. Overall, 75 A. flavus strains (86%) were characterized as producers of aflatoxins. The co-occurrence of at least two mycotoxins (AF/ZEA, FUM/ZEA, and AF/ZEA/FUM) was detected for five of the Z. mays samples (63%). Considering the high mycological bioburden and mycotoxin contamination, maize marketed in the metropolitan region of Asunción constitutes a potential risk to food safety and public health and requires control measures. Full article

Volatile organic compounds (VOCs) produced by A. flavus strains were first captured and identified to discern between non-aflatoxigenic and toxigenic phenotypes, and more recently to help with detecting fungal infection, but not with the goal of using VOCs produced by non-aflatoxigenic strains to inhibit growth and/or production of one or more mycotoxins (e.g., aflatoxin and cyclopiazonic acid) by toxigenic aspergilli. In this study, four Aspergillus strains from Louisiana (one non-aflatoxigenic and three toxigenic) were grown on various substrates and had their headspaces captured and analyzed by solid-phase microextraction/gas chromatography/mass spectroscopy (SPME/GC/MS), to find biocontrol and biomarker compounds. Here, we present a collection of nearly 100 fungus-related VOCs, many of which were substrate dependent. Thirty-one were produced across multiple replicates and the rest were observed in a single replicate. At least three VOCs unique to non-aflatoxigenic strain LA1 can be tested for biocontrol properties (e.g., euparone, 4-nonyne), and at least four VOCs unique to toxigenic strains LA2-LA4 can be explored as biomarkers (e.g., 2-heptanone, glycocyamidine) to detect their presence while infecting crops in the field or in storage. Full article

Aspergillus flavus is an opportunistic pathogen responsible for millions of dollars in crop losses annually and negative health impacts on crop consumers globally. A. flavus strains have the potential to produce aflatoxin and other toxic secondary metabolites, which often increase during plant colonization. To mitigate the impacts of this international issue, we employ a range of strategies to directly impact fungal physiology, growth and development, thus requiring knowledge on the underlying molecular mechanisms driving these processes. Here we utilize RNA-sequencing data that are obtained from in situ assays, whereby Zea mays kernels are inoculated with A. flavus strains, to select transcription factors putatively driving virulence-related gene networks. We demonstrate, through growth, sporulation, oxidative stress-response and aflatoxin/CPA analysis, that three A. flavus strains with knockout mutations for the putative transcription factors AFLA_089270, AFLA_112760, and AFLA_031450 demonstrate characteristics such as reduced growth capacity and decreased aflatoxin/CPA accumulation in kernels consistent with decreased fungal pathogenicity. Furthermore, AFLA_089270, also known as HacA, eliminates CPA production and impacts the fungus’s capacity to respond to highly oxidative conditions, indicating an impact on plant colonization. Taken together, these data provide a sound foundation for elucidating the downstream molecular pathways potentially contributing to fungal virulence. Full article