Morphologic, molecular and metabolic characterization of Aspergillus section Flavi in spices marketed in Lebanon

Microbial Decontamination of Cuminum cyminum Seeds Using "Intensification of Vaporization by Decompression to the Vacuum": Effect on Color Parameters and Essential Oil Profile

Cumin seeds are frequently utilized in herbal infusions and as flavoring agents in home cuisine. Nevertheless, studies have demonstrated that spices are frequently contaminated with pathogenic bacteria, including bacterial spores. The aim of this study was to assess the effectiveness of a new decontamination method called "Intensification of Vaporization by Decompression to the Vacuum" (IVDV) on intentionally contaminated Cuminum cyminum seeds. The study also examined the impact of this treatment on the color and oil profile of the treated samples. The untreated samples were inoculated with Escherichia coli (ATCC 25922) and Salmonella Typhimurium (ATCC 14028) and then subjected to IVDV treatment. Response surface methodology was employed to obtain safe, high-quality cumin seeds presenting a balance between microbial load, color, and oil profile. The optimal IVDV conditions were achieved at a pressure of 3.5 bar and a time of 133.45 s, resulting in typical 4 log reductions observed with 99.99% of Escherichia coli and Salmonella Typhimurium inactivation. The treated spices presented a mild color modification compared to the untreated ones, manifested by a darker shade (decreased L* value), reduced greenness (increased a* value), and heightened yellowness (increased b* value). The GC-MS analysis detected the existence of seven compounds in the treated cumin, with cuminaldehyde being the primary compound (83.79%). Furthermore, the use of IVDV treatment resulted in an increase in the total content of essential oils in some samples, whereby six monoterpenes were identified in the untreated sample compared to seven monoterpenes in IVDV-treated samples. This innovative technology demonstrated high efficacy in decontaminating C. cyminum seeds, improving the extractability of the essential oils while only slightly affecting the color.

Genome and secretome insights: unravelling the lignocellulolytic potential of Myceliophthora verrucosa for enhanced hydrolysis of lignocellulosic biomass

Lignocellulolytic enzymes from a novel Myceliophthora verrucosa (5DR) strain was found to potentiate the efficacy of benchmark cellulase during saccharification of acid/alkali treated bagasse by ~ 2.24 fold, indicating it to be an important source of auxiliary enzymes. The De-novo sequencing and analysis of M. verrucosa genome (31.7 Mb) revealed to encode for 7989 putative genes, representing a wide array of CAZymes (366) with a high proportions of auxiliary activity (AA) genes (76). The LC/MS QTOF based secretome analysis of M. verrucosa showed high abundance of glycosyl hydrolases and AA proteins with cellobiose dehydrogenase (CDH) (AA8), being the most prominent auxiliary protein. A gene coding for lytic polysaccharide monooxygenase (LPMO) was expressed in Pichia pastoris and CDH produced by M. verrucosa culture on rice straw based solidified medium were purified and characterized. The mass spectrometry of LPMO catalyzed hydrolytic products of avicel showed the release of both C1/C4 oxidized products, indicating it to be type-3. The lignocellulolytic cocktail comprising of in-house cellulase produced by Aspergillus allahabadii strain spiked with LPMO & CDH exhibited enhanced and better hydrolysis of mild alkali deacetylated (MAD) and unwashed acid pretreated rice straw slurry (UWAP), when compared to Cellic CTec3 at high substrate loading rate.

Species Identification and Mycotoxigenic Potential of Aspergillus Section Flavi Isolated from Maize Marketed in the Metropolitan Region of Asunción, Paraguay

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.

A multi-aspect analysis of two analogous aspergillus spp. belonging to section Flavi: aspergillus flavus and aspergillus oryzae

Microfungal isolates were routinely identified depending on both macro and micro morphological characteristics, sometimes, some fungal isolates appeared to be similar and such cases caused severe confusion for mycologists during the preliminary identification. During our previous studies dealing with isolation of fungi for some biotechnological applications; two mystifying species Aspergillus flavus and Aspergillus oryzae showed similar cultural and macroscopic features. Therefore, the current study aimed to easily distinguish between these two species depending on simple approaches which are routinely followed by a large segment of researchers. Investigation of the macroscopic features was performed to check the fungal growth on four different media (PDA, MEA, YES, and CYA) followed by microscopic examination using an ordinary light microscope, and scanning electron microscope SEM. Also, screening of secondary metabolites for both strains was preliminarily identified to find out the difference between their metabolic profiles. Finally, ITS rDNA was involved to clarify the molecular differences along their partial sequence. Conclusively, the BLAST strategy confirmed the similarity of ITS rDNA segments of both fungal strains that supported our hypothesis. The color of the fungal growth is a very critical factor whereas it is extensively influenced by the type of cultivation media. Accordingly, the YES medium was an inspiring tool assisting in prompt differentiation during the culture investigation step whereas A. oryzae and A. flavus appeared significant mustard yellow and olive green respectively. During the microscopic examination, the CYA medium also had a robust effect on the formation of the conidial chain whereas the knit long chain was observed in A. oryzae while the conidia appeared scattered and not in a chain in the case of A. flavus. Likewise, both two strains possessed different metabolic profiles where A. oryzae is not an Afla toxin producer, unlike A. flavus.

Public health risk associated with the co-occurrence of aflatoxin B1 and ochratoxin A in spices, herbs, and nuts in Lebanon

Background

Aflatoxin B1 and ochratoxin A are mycotoxins produced by filamentous fungi that attack crops on field and storage. Both mycotoxins present a risk on public health since aflatoxin B1 is a hepatotoxic and hepatocarcinogenic agent while ochratoxin A can be nephrotoxic. Those mycotoxins can be found in several food items including spices, herbs, and nuts.

Objectives

In Lebanon, few studies address aflatoxin B1 and ochratoxin A contamination in spices, herbs, and nuts. So, the aim of this study is to investigate the concentrations of those two mycotoxins particularly in spices and herbs and the concentration of aflatoxin B1 in nuts, and to determine the dietary exposure of the Lebanese population and their possible attribution to liver cancer and renal damage.

Methods

In this work, a total of 198 samples of spices, herbs, and nuts were collected from different sites. Aflatoxin B1 and ochratoxin A were quantified using immune-affinity columns. A food frequency questionnaire was used to quantify the consumption of spices, herbs, and nuts in Lebanon. Exposure to aflatoxin B1 and ochratoxin A was calculated accordingly and liver and kidney cancer risks were evaluated.

Results

Aflatoxin B1 was respectively found in 100, 20.4, and 98.6% of the spices, herbs, and nuts samples, while ochratoxin A was found in 100 and 44.4% of spices and herbs, respectively. Aflatoxin B1 was found at mean concentration of 0.97, 0.27, and 0.40 μg/kg in spices, herbs, and nuts, respectively while ochratoxin A was found at mean concentrations of 38.8 and 1.81 μg/kg in spices and herbs, respectively. Aflatoxin B1 occurrence was shown to be associated in this study with 0.017 additional cancer cases per 100,000 persons per year, and ochratoxin A weekly exposure was shown to be 5.04 ng/kg bw less than the Provisional Tolerable Weekly Intake of 100 ng/kg bw which indicates low risk of renal damage from spices and herbs consumption.

Conclusion

The consumption of spices, herbs, and nuts in Lebanon could lead to an increase in health risks associated with aflatoxin B1 and ochratoxin A, specifically spices. The reported occurrence may be directly related to poor storage conditions.

Asymmetrical lineage introgression and recombination in populations of Aspergillus flavus: Implications for biological control

Aspergillus flavus is an agriculturally important fungus that causes ear rot of maize and produces aflatoxins, of which B1 is the most carcinogenic naturally-produced compound. In the US, the management of aflatoxins includes the deployment of biological control agents that comprise two nonaflatoxigenic A. flavus strains, either Afla-Guard (member of lineage IB) or AF36 (lineage IC). We used genotyping-by-sequencing to examine the influence of both biocontrol agents on native populations of A. flavus in cornfields in Texas, North Carolina, Arkansas, and Indiana. This study examined up to 27,529 single-nucleotide polymorphisms (SNPs) in a total of 815 A. flavus isolates, and 353 genome-wide haplotypes sampled before biocontrol application, three months after biocontrol application, and up to three years after initial application. Here, we report that the two distinct A. flavus evolutionary lineages IB and IC differ significantly in their frequency distributions across states. We provide evidence of increased unidirectional gene flow from lineage IB into IC, inferred to be due to the applied Afla-Guard biocontrol strain. Genetic exchange and recombination of biocontrol strains with native strains was detected in as little as three months after biocontrol application and up to one and three years later. There was limited inter-lineage migration in the untreated fields. These findings suggest that biocontrol products that include strains from lineage IB offer the greatest potential for sustained reductions in aflatoxin levels over several years. This knowledge has important implications for developing new biocontrol strategies.

Lignocellulolytic enzymes from Aspergillus allahabadii for efficient bioconversion of rice straw into fermentable sugars and biogas

The study was aimed at developing lignocellulolytic strain capable of efficient hydrolysis of mild alkali deacetylated (MAD) rice straw. The valorisation of lignin rich black liquor obtained during pre-treatment of rice straw into biogas was also evaluated. Study reports highly proficient cellulolytic Aspergillus allahabadii strain harbouring a spectrum of CAZymes based on comparative genome wide analysis that was subjected to strain breeding for developing a hyper producing strain. The secretome analysis showed up-modulation and several folds increase in the CAZyme activities in the culture extracts of the developed strain MAN 40 when compared to parent. The cellulolytic cocktail of the developed strain showed 1.52 folds higher saccharification of MAD rice straw when compared to Cellic CTec 3. Moreover, in-situ addition of cellulases derived from developed strains resulted in ∼3.7 folds higher methane production during anaerobic digestion of mixture of lignin rich black liquor and differently treated rice straw.

Prevalence, Identification and Mycotoxigenic Potential of Fungi in Common Spices Used in Local Malaysian Cuisines

Spices are widely used in various cuisines in Malaysia to enhance the flavour and aroma. However, spices are susceptible to fungal infection, leading to mycotoxin contamination if the storage conditions are favourable for fungal growth. Thus, this study aimed to identify fungal species in spices commonly used in local Malaysian cuisines and determine their prevalence and mycotoxigenic potential. A total of 110 spice samples consisting of cumin, fennel, coriander, peppers (black pepper and white pepper), chillies (dried chilli, chilli paste and chilli powder), cinnamon, star anise, cloves, curry powder and korma powder were randomly purchased from retail markets in Penang. The samples were analysed for the total fungal count (ground spices) and the incidence of fungal infection (whole spices). The fungal species isolated from spices were identified based on morphological and molecular approaches, and the mycotoxigenic potential was determined using the Coconut Cream Agar method. The results showed that coriander seeds (ground) recorded the highest total fungal count (ADM 3.08 log CFU/g; DG18 3.14 log CFU/g), while black pepper (whole) recorded the highest incidence of fungal infection (94%). Interestingly, star anise and cloves were free from fungal contamination. The mycotoxigenic fungi of A. flavus and A. niger recorded the highest isolation frequency in ground and whole spices. These findings indicate the risk of mycotoxin exposure to consumers due to the high consumption of spices in local Malaysian cuisine.

Diversity of Fusarium Species Isolated from Symptomatic Plants Belonging to a Wide Range of Agri-Food and Ornamental Crops in Lebanon

Lebanon is a small Mediterranean country with different pedoclimatic conditions that allow the growth of both temperate and tropical plants. Currently, few studies are available on the occurrence and diversity of Fusarium species on Lebanese crops. A wide population of Fusarium strains was isolated from different symptomatic plants in the last 10 years. In the present investigation, a set of 134 representative strains were molecularly identified by sequencing the translation elongation factor, used in Fusarium as a barcoding gene. Great variability was observed, since the strains were grouped into nine different Fusarium Species Complexes (SCs). Fusarium oxysporum SC and Fusarium solani SC were the most frequent (53% and 24%, respectively). Members of important mycotoxigenic SCs were also detected: F. fujikuroi SC (7%), F. sambucinum SC (5%), F. incarnatum-equiseti SC (3%), and F. tricinctum SC (4%). Two strains belonging to F. lateritium SC, a single strain belonging to F. burgessii SC, and a single strain belonging to F. redolens SC were also detected. This paper reports, for the first time, the occurrence of several Fusarium species on Lebanese host plants. The clear picture of the Fusarium species distribution provided in this study can pose a basis for both a better understanding of the potential phytopathological and toxicological risks and planning future Fusarium management strategies in Lebanon.

Substantive Morphological Descriptions, Phylogenetic Analysis and Single Nucleotide Polymorphisms of Aspergillus Species From Foeniculum vulgare

Ascomycetous fungi are found associated with a wide variety of substrates which range from fresh water to marine ecosystems, tropical to temperate forest soils and deserts, throughout the world over. These demystifying fungi exist as endophytes, pathogens and saprobes. They have been studied due to their ability to contaminate foods and feedstuffs, causing an elaboration of mycotoxins. The objectives of the study included extensive analyses of the morphological features of fungi, especially Aspergilli, which have been presented while studying them on specific mycological media. It is also an elaborate compilation of substantive macro- and micro-morphological characterization of different Aspergilli isolated from the spice Foeniculum vulgare used in India and other countries in the world. Further, a first of its kind attempt has been made to study their relative abundance and frequency of occurrence, molecular phylogeny and genetic relatedness to characterize the Aspergilli into specific sections, groups and clades. Single nucleotide polymorphism (SNP) analysis was carried out to evaluate the functional consequences of nucleotide variations, synonymous and non-synonymous mutations in the protein structure. The study resulted in a total of 3,506 Aspergillus isolates, which were obtained from seventy (70) fennel samples, representing 14 Aspergillus species. The two most frequently found species were A. niger and A. flavus with a relative abundance of 32.24 and 11.63%, respectively. The taxonomy and current placements have been reappraised with suggestions and prospects for future research from six sections namely Terrei, Flavi, Fumigati, Nidulantes, Nigri, and Versicolores. In addition, a total number of 27 isolates were studied and deposited at the National Centre for Biotechnology Information (NCBI) and five Aspergillus species have been identified and are being reported for the first time from the fennel seeds, based on partial sequence analysis of the official fungal barcode namely, Internal Transcribed Spacer (ITS) and a functional gene, beta tubulin gene locus, coupled with phenotypic characterization. SNPs for specific DNA regions have been used to identify variants in Aspergilli obtained from Indian fennel seeds for the first time. The need for a polyphasic approach of morphological identification and genetic characterization of Aspergilli from Foeniculum vulgare is addressed and presented here in adequate detail. Our current work makes extensive use of partial beta-tubulin gene sequences analyses to evaluate the association between SNPs in five Aspergillus species sections.

Influence of Atmospheric Cold Plasma Exposure on Naturally Present Fungal Spores and Physicochemical Characteristics of Sundried Tomatoes (Solanum lycopersicum L.)

This research aimed to evaluate the impact of atmospheric cold plasma (ACP) treatment on the fungal spores naturally present in sundried tomatoes, as well as their influence on the physico-chemical properties and antioxidant activity. ACP was performed with a Surface Dielectric Barrier Discharge (SDBD), applying 6 kV at 23 kHz and exposure times up to 30 min. The results showed a significant reduction of mesophilic aerobic bacteria population and of filamentous fungi after the longer ACP exposure. In particular, the effect of the treatment was assessed on Aspergillus rugulovalvus (as sensible strain) and Aspergillus niger (as resistant strain). The germination of the spores was observed to be reliant on the species, with nearly 88% and 32% of non-germinated spores for A. rugulovalvus and A. niger, respectively. Fluorescence probes revealed that ACP affects spore viability promoting strong damage to the wall and cellular membrane. For the first time, the sporicidal effect of ACP against A. rugulovalvus is reported. Physicochemical parameters of sundried tomatoes such as pH and water activity (aw) were not affected by the ACP treatment; on the contrary, the antioxidant activity was not affected while the lycopene content was significantly increased with the increase in ACP exposure time (p ≤ 0.05) probably due to increased extractability.

Fungal communities in Nelumbinis semen characterized by high-throughput sequencing

For a long period, Nelumbinis semen has been widely used as a medicinal and edible product. However, it is susceptible to contamination with toxigenic fungi and aflatoxins during the growth, collection, transportation, and storage processes, causing serious health threats to humans and huge economic losses. Effectively monitoring the fungal communities is of great importance to avoid aflatoxins contamination in Nelumbinis semen. High-throughput sequencing (HTS) is a new technology to evaluate fungal communities so as to overcome the limitations of the traditional cultural ways. In this study, the ITS2 based Illumina-MiSeq platform was developed to evaluate the fungal communities in normal and moldy Nelumbinis semen by using the HTS technology. Two different primer pairs were introduced to compare their performance in amplifying the target gene. The primer pair that produced more reads was selected to analyze the results. In all the nine tested Nelumbinis semen samples, 2 phyla, 5 classes, 6 orders, 8 families, 9 genera and 4 species were detected. A total of 9 genera were spotted, of which, Aspergillus (0.04%-72.93%) and Rhizopus (0.002%-48.12%) were the most dominant. ANOISM analysis showed no significant differences in the normal and moldy groups. The use of HTS technology can detect the fungal communities in complex Nelumbinis semen samples, providing an early warning for toxigenic fungi and aflatoxins contamination to warrant their quality and safety.

Differentiation of Aspergillus flavus from Aspergillus oryzae Targeting the cyp51A Gene

Aspergillus flavus is one of the most important agents of invasive and non-invasive aspergillosis, especially in tropical and subtropical regions of the world, including Iran. Aspergillus oryzae is closely related to A. flavus, and it is known for its economic importance in traditional fermentation industries. Reports of infection due to A. oryzae are scarce. Several studies reported that differentiating these two species in clinical laboratories is not possible using MALDI-TOF or by targeting fungal barcode genes, such as Internal Transcribed Spacer (ITS) and β-tubulin (benA). The species-level identification of causative agents and the determination of antifungal susceptibility patterns can play significant roles in the outcome of aspergillosis. Here, we aimed to investigate the discriminatory potential of cyp51A PCR-sequencing versus that of the ITS, benA and calmodulin (CaM) genes for the differentiation of A. flavus from A. oryzae. In a prospective study investigating the molecular epidemiology of A. flavus in Iran between 2008 and 2018, out of 200 clinical isolates of A. flavus, 10 isolates showed >99% similarity to both A. flavus and A. oryzae. Overall, the ITS, β-tubulin and CaM genes did not fulfil the criteria for differentiating these 10 isolates. However, the cyp51A gene showed promising results, which warrants further studies using a larger set of isolates from more diverse epidemiological regions of the world.

Aspergillus derived mycotoxins in food and the environment: Prevalence, detection, and toxicity

Aspergillus species are the paramount ubiquitous fungi that contaminate various food substrates and produce biochemicals known as mycotoxins. Aflatoxins (AFTs), ochratoxin A (OTA), patulin (PAT), citrinin (CIT), aflatrem (AT), secalonic acids (SA), cyclopiazonic acid (CPA), terrein (TR), sterigmatocystin (ST) and gliotoxin (GT), and other toxins produced by species of Aspergillus plays a major role in food and human health. Mycotoxins exhibited wide range of toxicity to the humans and animal models even at nanomolar (nM) concentration. Consumption of detrimental mycotoxins adulterated foodstuffs affects human and animal health even trace amounts. Bioaerosols consisting of spores and hyphal fragments are active elicitors of bronchial irritation and allergy, and challenging to the public health. Aspergillus is the furthermost predominant environmental contaminant unswervingly defile lives with a 40-90 % mortality risk in patients with conceded immunity. Genomics, proteomics, transcriptomics, and metabolomics approaches useful for mycotoxins' detection which are expensive. Antibody based detection of toxins chemotypes may result in cross-reactivity and uncertainty. Aptamers (APT) are single stranded DNA (ssDNA/RNA), are specifically binds to the target molecules can be generated by systematic evolution of ligands through exponential enrichment (SELEX). APT are fast, sensitive, simple, in-expensive, and field-deployable rapid point of care (POC) detection of toxins, and a better alternative to antibodies.

Molecular and HPLC-based approaches for detection of aflatoxin B1 and ochratoxin A released from toxigenic Aspergillus species in processed meat

BACKGROUND

Meat-products are considered an enriched media for mycotoxins. This study aimed to investigate the prevalence of toxigenic Aspergillus species in processed meat samples, HPLC-quantitative measurement of aflatoxin B1 and ochratoxin A residues, and molecular sequencing of aflR1 and pks genes. One hundred and twenty processed beef meat specimens (basterma, sausage, and minced meat; n = 40 for each) were collected from Ismailia Province, Egypt. Samples were prepared for total mold count, isolation, and identification of Aspergillus species. All samples were analyzed for the production of both Aflatoxin B1 and Ochratoxin A mycotoxins by HPLC. Molecular identification of Aspergillus flavus and Aspergillus ochraceus was performed using PCR amplification of the internal transcribed spacer (ITS) region; furthermore, the aflR1 and pks genes were sequenced.

RESULTS

The total mold count obtained from sausage samples was the highest one, followed by minced meat samples. The prevalence of A. flavus was (15%), (7.5%), and (10%), while the prevalence of A. ochraceus was (2.5%), (10%), and (0%) in the examined basterma, sausage, and minced meat samples, respectively. Using PCR, the ITS region was successfully amplified in all the tested A. flavus and A. ochraceus strains. Aflatoxin B1 was detected in six basterma samples (15%). Moreover, the ochratoxin A was detected only in four sausage samples (10%). The aflR1 and pks genes were amplified and sequenced successfully and deposited in the GenBank with accession numbers MF694264 and MF694264, respectively.

CONCLUSIONS

To the best of our knowledge, this is the first report concerning the HPLC-Molecular-based approaches for the detection of aflatoxin B1 and ochratoxin A in processed beef meat in Egypt. The production of aflatoxin B1 and ochratoxin A in processed meat constitutes a public health threat. Aflatoxin B1 is commonly associated with basterma samples. Moreover, ochratoxin A was detected frequently in sausage samples. The routine inspection of mycotoxins in processed meat products is essential to protect human consumers.

A Review on Mycotoxins and Microfungi in Spices in the Light of the Last Five Years

Spices are imported worldwide mainly from developing countries with tropical and/or subtropical climate. Local conditions, such as high temperature, heavy rainfall, and humidity, promote fungal growth leading to increased occurrence of mycotoxins in spices. Moreover, the lack of good agricultural practice (GAP), good manufacturing practice (GMP), and good hygienic practice (GHP) in developing countries are of great concern. This review summarizes recent data from a total of 56 original papers dealing with mycotoxins and microfungi in various spices in the last five years. A total of 38 kinds of spices, 17 mycotoxins, and 14 microfungi are discussed in the review. Worldwide, spices are rather overlooked in terms of mycotoxin regulations, which usually only cover aflatoxins (AFs) and ochratoxin A (OTA). In this paper, an extensive attention is devoted to the limits on mycotoxins in spices in the context of the European Union (EU) as well as other countries. As proven in this review, the incidence of AFs and OTA, as well as other mycotoxins, is relatively high in many spices; thus, the preparation of new regulation limits is advisable.

Development of PCR, LAMP and qPCR Assays for the Detection of Aflatoxigenic Strains of Aspergillus flavus and A. parasiticus in Hazelnut

Aspergillus flavus and A. parasiticus are two species able to produce aflatoxins in foodstuffs, and in particular in hazelnuts, at harvest and during postharvest phase. As not all the strains of these species are aflatoxin producers, it is necessary to develop techniques that can detect aflatoxigenic from not aflatoxigenic strains. Two assays, a LAMP (loop-mediated isothermal amplification) and a real time PCR with TaqMan^® probe were designed and validated in terms of specificity, sensitivity, reproducibility, and repeatability. The capability of the strains to produce aflatoxins was measured in vitro and both assays showed to be specific for the aflatoxigenic strains of A. flavus and A. parasiticus. The limit of detection of the LAMP assay was 100–999 picograms of DNA, while the qPCR detected 160 femtograms of DNA in hazelnuts. Both techniques were validated using artificially inoculated hazelnuts and naturally infected hazelnuts. The qPCR was able to detect as few as eight cells of aflatoxigenic Aspergillus in naturally infected hazelnut. The combination of the LAMP assay, which can be performed in less than an hour, as screening method, with the high sensitivity of the qPCR, as confirmation assay, is able to detect aflatoxigenic strains already in field, helping to preserve the food safety of hazelnuts.

Aspergillus spp. presence on mechanical protection gloves from the waste sorting industry

The organic material present on waste sorting units serve as a substrate for different microorganisms, increasing workers' exposure to Aspergillus spp. This study intends to assess the Aspergillus spp. contamination on Mechanical Protection Gloves (MPG) from different workstations and understand the role of MPG in workers' exposure to these genera. Sixty-seven used MPG were collected from different workstations and extracts were seeded on malt extract agar (MEA) supplemented with chloramphenicol (0.05%) and dichloran glycerol (DG18). The same extracts were used for the molecular detection of fungal species/strains, with reported toxigenic potential, namely Aspergillus sections (Circumdati, Flavi, Fumigati, and Nidulantes). Among Aspergillus spp., the sections with the highest prevalence on MEA were Nigri (88.29%) and Fumigati (8.63%), whereas on DG18 were Nigri (31.79%) and Circumdati (30.77%). Aspergillus section Circumdati was detected in 22 MPG samples by RT-PCR (32.84%), Fumigati in 59 samples (88.06%), Nidulantes in 61 samples (91.05%), and Flavi in 6 samples (8.96%). It was showed that, even with daily replacement, MPG presented Aspergillus spp. contamination. Thus, a more regular replacement of MPG and the adoption of complementary hygienic procedures by workers are critical to guarantee workers' protection in this occupational environment.