Potential Mycotoxin Research Articles

Fermentation by Penicillium polonicum improves the functional components and biological effects of orange peel via producing β-glucosidase without the risk of potential mycotoxins

This paper presented the initial investigation into the impact of Penicillium polonicum fermentation on the functional components and bioactivities of navel orange peel. The fermentation process resulted in a notable enhancement of the total flavonoid content (TFC), total phenolic content (TPC), antioxidant capacity, antibacterial activity, and antiglycation activity of orange peel. Eighteen flavonoids were isolated and identified from the ethanolic extract of fermented orange peel (FEE) by employing chromatographic and spectroscopic techniques. The results of the HPLC analysis showed that three flavanones (naringenin, hesperetin, and isosakuranetin) were newly produced and present in high concentrations in FEE, with hesperetin being the most abundant component (39.74 mg/g) in comparison to the ethanolic extract of unfermented orange peel (EE). The TPC, TFC, antioxidant, and antiglycation activities of FEE, as well as the enzymatic activity of β-glucosidase in the fermented orange peels, showed a gradual increase with the progression of fermentation time over a five-month period. HPLC analysis revealed that the fermentation metabolites generated by P. polonicum in rice and orange peel media exhibited distinct profiles, indicating that the fermentation of orange peel by P. polonicum did not result in the production of potential mycotoxins. The findings of this study provided a scientific basis for the high-value utilization of navel orange peels and established a reference point for the potential applications of other peel byproducts via microbial fermentation.

Assessment of Mycotoxins in Infants and Children Cereal-Based Foods: Dietary Exposure and Potential Health Risks

AbstractPublic health concerns are rising regarding potential mycotoxin contamination in processed cereal-based products consumed by infants and young children. Due to their developing physiological systems and greater vulnerability, children are particularly susceptible to the adverse health effects of mycotoxins. This study investigated the presence of a wide range of mycotoxins (20 in total, encompassing various chemical classes, such as aflatoxins, ochratoxins, trichothecenes, zearalenones, fumonisins, citrinin and sterigmatocystin) in readily available processed cereal-based foods targeted towards infants and children in Portugal. Among the 148 analysed samples, 43% contained at least one of the targeted mycotoxins. Aflatoxin B1 (8.1%) and fumonisin B1 (10.8%) were the most commonly detected regulated mycotoxins, while emerging mycotoxins like enniatin B (14.9%) and beauvericin (10.1%) were also prevalent. The most commonly co-occurring mycotoxins were ENNB + BEA and FB1 + FB2. Although the Estimated Daily Intake of non-carcinogenic mycotoxins in most products was below their respective Tolerable Daily Intake (DONs and FBs (1 μg/kg bw/day), HT-2 and T-2 (0.02 μg/kg bw/day), ZEN (0.25 μg/kg bw/day), and CIT (0.2 μg/kg bw/day)), Hazard Quotient and Hazard Index values exceeded safe thresholds, indicating potential health risks.

Monitoring fungi and mycotoxin potential in pistachio nuts of Turkish origin: A snap-shot for climate change scenario

Pistachio (Pistacia vera L.) is an economically important tree nut. Due to its nutritional properties and health benefits, it is considered a healthy food and thus widely consumed worldwide. However, fungal contamination of the commodities has received considerable attention because of possible contamination by toxigenic fungi, important source of mycotoxins, resulting from secondary metabolism and hazards to health consumer. Members of the genus Aspergillus, mainly Aspergillus flavus and Aspergillus niger, are reported as occurring most frequently on pistachio nuts, because able to grow in the presence of low amounts of water and to produce mycotoxins (aflatoxins and ochratoxins), that are well known for their harmful health effects on humans.Monitoring the contaminating fungal species is particularly worthy of note also in climate change scenario, allowing to notice changes in fungal population composition through the time.This study aimed to contribute to collect data about fungal population and mycotoxins occurred in pistachio samples collected in Turkey: prevalence of 2 species, A. flavus and Aspergillus tubingensis, was assessed. The A. flavus strains consisted of a mixed population of aflatoxin producers and non-producing strains in vitro, with evidence of a new genotype in gene cluster within strains of aflatoxin non-producing chemotype.

Characterization and diversity of potential mycotoxin producing endophytic fungi isolated from maize husk leaves

Maize (Zea mays L.) is an important staple food due to its good nutritional profile. Unfortunately, maize can be vulnerable to contamination by fungi, which are capable of producing mycotoxins that have an impact on human and animal health, crop productivity and lead to economic losses. In addition, the ubiquitous presence of mycotoxin-producing fungi in maize poses significant challenges to food safety and economic stability. Mycotoxins are toxic secondary metabolites produced by certain fungi, which, when ingested by humans or animals through contaminated maize products can lead to a variety of health issues. There is a shift of non-pathogenic microbes to pathogenic state due to unfavourable conditions arising. The aim of this study was to characterize and identify fungi that have the potential to produce mycotoxins isolated from maize husks. The study identified Fusaria sp., Aspergillus and Penicillium sp. as target species since they are often regarded as primary mycotoxin producing fungi, which often contaminates the maize plants. Ten (n=10) healthy (disease-free) and mature maize samples were obtained, and a total of 200 maize husk segments were utilized to isolate eighty-four (n=84) endophytic fungi. Preliminary identification was conducted using macroscopic and microscopic characteristics. Molecular processes using the Internal transcribed spacer region (ITS1 and ITS4) were used for PCR amplification as a confirmatory test. A total of 13 isolates were identified by macroscopic and microscopic characterization based on morphological features and their identification was confirmed using molecular techniques. Fusaria sp. were found to be predominant (46%), followed by Aspergillus sp. (39%) and Penicillium sp. (15%). The findings suggest a community of mycotoxin producing fungi inhibited within the maize husks. Under unfavourable conditions, these fungi might be the source of contamination and produce mycotoxins. In the face of changing environmental conditions and evolving fungal threats, our research serves as a valuable resource for understanding and addressing the challenges posed by mycotoxin contamination in maize. Effective strategies and interventions are essential to mitigate the impact of these fungi on food security, human health, and the global maize industry. Key words: Endophytes; fungi; food safety; maize; maize husks; mycotoxin; mycotoxin-producing fungi

Analysis of composition and molecular characterization of mycobiota occurring on surface of cheese ripened in Dossena's mine

Accurate identification of the fungal community spontaneously colonizing food products, aged in natural and not controlled environments, provides information about potential mycotoxin risk associated with its consumption.Autochthonous mycobiota colonizing cheese aging in Dossena mines, was investigated and characterized by two approaches: microbial isolations and metabarcoding. Microbial isolations and metabarcoding analysis were conducted on cheese samples, obtained by four batches, produced in four different seasons of the year, aged for 90 and 180 days, by five dairy farms. The two approaches, with different taxonomical resolution power, highlighted Penicillium biforme among filamentous fungi, collected from 58 out of 68 cheeses, and Debaryomyces hansenii among yeasts, as the most abundant species (31 ÷ 65%), none representing a health risk for human cheese consumption. Shannon index showed that the richness of mycobiota increases after 180 days of maturation. Beta diversity analysis highlighted significant differences in composition of mycobiota of cheese produced by different dairy farms and aged for different durations. Weak negative growth interaction between P. biforme and Aspergillus westerdijkiae by in vitro analysis was observed leading to hypothesize that a reciprocal control is possible, also affected by natural environmental conditions, possibly disadvantageous for the last species.

Emerging Alternaria toxins present in naturally contaminated dried tomatoes and their reduction using cold atmospheric plasma

This study investigated the efficacy of cold atmospheric plasma (CAP) treatment in degrading the emerging Alternaria toxins as pure molecules and as natural contaminants in dried tomatoes. The analyses of 25 batches of dried tomatoes showed that more than 40% of samples were contaminated with tenuazonic acid (TeA), one with Alternariol (AOH), while Tentoxin (TEN), Alternariol monomethyl ether (AME) and Altenuene (ALT) were not detected. CAP under ozone (O3) and NOx regimes were used to reduce the mycotoxin contamination, the results shown that O3 regime was more effective against all mycotoxins tested, while NOx regime showed different efficacy depending on the specific mycotoxin. The Weibull model proved to be appropriate for the degradation kinetics of all Alternaria toxins, regardless of the kinetic order they possess. Under the O3 regime, the resistance of the mycotoxin was AME > AOH > TEN > TeA > ALT. Our studies have shown for the first time that CAP reduces Alternaria toxins in naturally contaminated dried tomatoes. In particular, the rate of degradation under O3 regime increased significantly with the longest exposure time, reaching 52.80 ± 1.21 % of mycotoxin degradation. Our results expand our knowledge of CAP treatment as a potential means of reducing mycotoxin contamination in food. Further studies will be carried out to investigate the potential mycotoxin degradation products and to ensure food safety.

Storage mycotoxin producing fungi in Hungarian sorghum (Sorghum bicolor L. Moench) samples—molecular approach of Fusarium spp.

AbstractThe last few years have been a huge challenge for every farmer in Europe and Hungary because of the increase in hot days and the decrease in precipitation. These facts induced the farmer’s interest in sorghum because it has better stress tolerance than many other cereales, but little is known about mycotoxin-producing fungi, which can infect this crop. Mycotoxins are secondary metabolites of filamentous fungi, and they are not only phytotoxic but also harmful to humans and animals. This study aimed to determine the internal infection caused by Alternaria spp., Fusarium spp., and Aspergillus spp., which are known as mycotoxin-producing fungi in food raw material. In our study in the case of sorghum, the presence of various mycotoxin-producing fungi was detected on Fusarium selective media (Nash and Snyder media), and the results indicate that these genera are present in sorghum grains as potential mycotoxin producers. To determine which Fusarium species is occurring in our sorghum grain samples, a molecular genetic study was performed on isolated fungi using the TEF region primer pairs to identify the occurring Fusarium species. We mainly identified Fusarium proliferatum in our conventional sorghum samples. The results show that the mentioned mycotoxin-producing fungi are in the sorghum grains and may pose a risk to the safety of feed and food because they may produce mycotoxins in the field or while being stored.

Mycotoxic effects of entomopathogenic fungi of fall armyworm (Spodoptera frugiperda J.E. Smith) on poultry feed safety

This study was carried out to analyze mycotoxins of entomopathogenic fungi of fall armyworm (Spodoptera frugiperda J.E. Smith) and poultry feed safety. An experiment was set up to assess the types of mycotoxins produced by entomopathogenic fungal parasite of fall armyworm larvae and their subsequent effect on the safety of the larvae as a feed ingredient. Molecular characterization was done to estimate the diversity of entomopathogenic fungi on fall armyworm larvae specimens from the treatment plots. Sequenced data was analyzed and processed using Molecular Evolutionary Genetic Analysis 6.0 software. The results showed relative diversity of fall armyworm larvae with 11 species isolated belonging to Aspergillus, Penicillium, Fusarium, Trichoderma, Bipolaris and Irpex genus. Some of these are potential mycotoxin producing fungi. Although isolated fungi potentially produce Ochratoxin, Fumonisin, Zearalenone and Trichothecene mycotoxins, only aflatoxins were analyzed in this study. About 3.98 μg /kg of aflatoxin was observed using the ELISA total assay which is within the threshold toxicity levels set in Kenya for feed of about 20 μg /kg. While this is under the threshold set by Kenya, it is still enough to cause concern as the cumulative exposure of even low doses can have impacts. This study therefore concludes that, Spodoptera frugiperda can be potentially contaminated with aflatoxins and when formulating poultry diets, there is need to monitor production so that the quality is not compromised and feed safety is ensured. Further studies are recommended to determine how much produced aflatoxins are then transferred into the poultry products such as eggs and meat.

Kernel Bioassay Evaluation of Maize Ear Rot and Genome-Wide Association Analysis for Identifying Genetic Loci Associated with Resistance to Fusarium graminearum Infection.

Gibberella ear rot (GER) caused by Fusarium graminearum (teleomorph Gibberella zeae) is one of the most destructive diseases in maize, which severely reduces yield and contaminates several potential mycotoxins in the grain. However, few efforts had been devoted to dissecting the genetic basis of maize GER resistance. In the present study, a genome-wide association study (GWAS) was conducted in a maize association panel consisting of 303 diverse inbred lines. The phenotypes of GER severity were evaluated using kernel bioassay across multiple time points in the laboratory. Then, three models, including the fixed and random model circulating probability unification model (FarmCPU), general linear model (GLM), and mixed linear model (MLM), were conducted simultaneously in GWAS to identify single-nucleotide polymorphisms (SNPs) significantly associated with GER resistance. A total of four individual significant association SNPs with the phenotypic variation explained (PVE) ranging from 3.51 to 6.42% were obtained. Interestingly, the peak SNP (PUT-163a-71443302-3341) with the greatest PVE value, was co-localized in all models. Subsequently, 12 putative genes were captured from the peak SNP, and several of these genes were directly or indirectly involved in disease resistance. Overall, these findings contribute to understanding the complex plant-pathogen interactions in maize GER resistance. The regions and genes identified herein provide a list of candidate targets for further investigation, in addition to the kernel bioassay that can be used for evaluating and selecting elite germplasm resources with GER resistance in maize.

Characterization of Argentine commercial bee pollen intended for human consumption

Bee pollen is consumed as a dietary supplement. Its quality parameters are regulated by the Argentine Food Code (AFCode). The present study characterized 10 commercial dehydrated samples from five Argentine provinces to provide information on hygienic quality and health safety. We assessed their microbiological quality, including potential mycotoxins. We also determined their botanical origin and moisture. Results showed that seven out of ten samples presented lower counts of culturable heterotrophic mesophilic bacteria than those allowed by the AFCode. In contrast, all samples showed higher filamentous fungi and yeast counts than the level approved by the AFCode. No fumonisin or deoxynivalenol was detected; we observed only aflatoxin B2 in one sample and ochratoxin A in two. The results of the botanical origin of samples showed that all samples had a predominant pollen type, except one. The microbiological quality of all samples agreed with that required by the AFCode, except filamentous fungi and yeasts. In addition, we found variations among samples from the same province. Therefore, if pollen is intended for human consumption, appropriate hygiene standards must be applied to all bee pollen production operations. Highlights: The microbiological quality of bee pollen samples, regardless of the province or botanical origin, agreed with the requirements of the AFCode, except for filamentous fungus and yeast. All samples showed filamentous fungus and yeast counts higher than the permitted level in the AFCode. Mycotoxin levels found in bee pollen were far from the limits allowed in humans (10 µg.kg-1) by regulations for other foods. All samples analyzed were pollen mixes verified by identifying numerous botanical species. The characterization of Argentinian commercial bee pollen showed that it was suitable for human consumption.

Preharvest and postharvest management practices related to mycotoxin contamination in maize in Ethiopia – a review

Abstract Mycotoxins are fungal metabolites that commonly contaminate food crops such as maize. Conducive climatic conditions together with improper crop value chain practices are favorable for mycotoxin contamination. Previous studies in Ethiopia have indicated that mycotoxin contamination in maize is prevalent. For the implementation of proper mycotoxin prevention and control strategies, identifying the current local value chain practices that are related to mycotoxin contamination is needed. This review investigates current preharvest and postharvest management practices of maize cultivation in Ethiopia in relation to mycotoxin contamination and identifies gaps in knowledge and priority areas for future research. Findings indicate that the majority of applied preharvest and postharvest practices of maize in Ethiopia seem to favor mycotoxin contamination. Recent developments in grain drying and storage technologies, which are also potential mycotoxin management strategies, are facing constraints for proper implementation in subsistence farmers’ level.

Harmonizing Drying Time, Layer Thickness, and Drier Zones for Drying Kinetics: Quality and Safety of Solar Tunnel-Dried Wet-Processed Parchment Coffee (Coffea arabica L.).

Tunnel solar dryer is the recently used drying method for better quality and safety of parchment coffee. However, the higher variation of drying temperature and RH along the long tunnel solar dryer results in a heterogeneous environment in the tunnel, which could make parchment coffee dried at different times or with different moisture contents. This study is aimed at investigating the effect of solar tunnel dryer zones at different zones of the dryer, divided into three zones from the inlet to the exit side of the drier and drying layer thicknesses on the drying time, drying kinetics, physicochemical, sensory, and fungal growth loads of parchment coffee. Furthermore, seven mathematical models were evaluated to select the best-fitting model for a specific zone to predict drying time. Results showed that dryer zones significantly (p < 0.05) interacted with layer thickness for most of the measured parameters except titratable acidity and sensory properties. The dryer zone, coupled with the reduction in drying layer thickness, caused an increase in effective diffusivity and moisture removal rate and reduced drying time. The drying time to reach constant moisture content varied from 14 to 17 hours. Overall raw bean, cup, and total quality varied from 36.3 to 37, 48 to 51, and 84.3 to 87.3%, respectively. Values for physicochemical parameters ranged from 5.3 to 6.9 (pH), 2.1 to 2.6% (titratable acidity), 2.3 to 4.3°Brix TSS, 10.9 to 15.2% (ether extract), 39.2 to 53.5GAE/g (total phenolic content), and 38.5 to 59.2 (DPPH scavenging capacity). The fungal infection percentage at the end of drying varied from 4 to 93.3%, which could be associated with potential mycotoxin formation if recommended conditions were not maintained. In general, for better quality, similar drying times, and a lesser fungal load, it is recommended to use 4, 5, and 6 cm layer thickness in zones one, two, and three, respectively. The drying kinetics of parchment coffee in different dryer zones with different drying layer thicknesses showed variation. Zone one at 2 and 4 cm layer thicknesses is best described by the Verma model. Four- and six-centimetre layer thicknesses in zones 2 and 3 are best described by the modified Midilli model.

Fungal microbiome related to mycotoxin contamination in medicinal and edible seed Semen Persicae

Medicinal and edible seed Semen Persicae is susceptible to mycotoxin and fungal contamination. However, the occurrence of mycotoxin contamination and fungal infection is still unclear. In this paper, ultra-high performance liquid chromatography-tandem triple quadrupole mass spectrometry and high-throughput sequencing were conducted to determine the mycotoxin contents and fungal abundances of Semen Persicae. 42.86% of samples were positive for aflatoxin B1 (26.48–48.37 μg/kg) and 28.57% of samples were positive for aflatoxin B2 (1.47–4.82 μg/kg). Ochratoxin A and fumonisin B1 were only detected in one sample (91.02 and 34.61 μg/kg, respectively). Chao 1 and Shannon indices were significantly higher in the Dalian of Liaoning, Baotou of Innermongolia and Langfang of Hebei regions than in other groups. Ascomycota, Basidiomycota, Wallemia, Candica, Saccharomyces and Aspergillus were the predominant fungi and they were significantly region-specific. Simultaneously, the diversity, composition and co-occurrence network complexity in the mycotoxin-free group were significantly higher than those in the mycotoxin-contaminated group. Spearman correlation analysis showed aflatoxins, ochratoxin A and fumonisins contents were positively and significantly correlated with the abundances of Aspergillus, Rhodotorula, Wallemia and Candida. In conclusion, this study reported the prevalence of mycotoxin contamination and the great diversity of fungi associated with Semen Persicae for the first time, providing an early warning for subsequent potential mycotoxin biosynthesis.

Encapsulation of Ammoides pusila Essential Oil into Mesoporous Silica Particles for the Enhancement of Their Activity against Fusarium avenaceum and Its Enniatins Production

Essential oils (EOs) that have antifungal activity and mycotoxin reduction ability are candidates to develop bioactive alternatives and environmentally friendly treatment against Fusarium species in cereals. However, their practical use is facing limitations such as high volatility, UV sensitivity, and fast oxidation. Encapsulation techniques are supposed to provide protection to the EOs and control their release into the environment. Ammoides pusilla essential oil (AP-EO) proved to be an efficient inhibitor of Fusarium avenaceum growth and its enniatins (ENNs) production. In the present work, AP-EO was encapsulated, using the impregnation method, into mesoporous silica particles (MSPs) with narrow slit pores (average diameter = 3.1 nm) and coated with chitosan. In contact assays using an agar medium, the antifungal activity of AP-EO at 0.1 µL mL-1 improved by three times when encapsulated into MSPs without chitosan and the ENNs production was significantly inhibited both in coated and non-coated MSPs. Controls of MSPs also inhibited the ENNs production without affecting the mycelial growth. In fumigation experiments assessing the activity of the EO volatile compounds, encapsulation into MSPs improved significantly both the antifungal activity and ENNs inhibition. Moreover, coating with chitosan stopped the release of EO. Thus, encapsulation of an EO into MSPs improving its antifungal and antimycotoxin properties is a promising tool for the formulation of a natural fungicide that could be used in the agriculture or food industry to protect plant or food products from the contamination by toxigenic fungi such as Fusarium sp. and their potential mycotoxins.

Isolation of Aspergillus flavus strains from Bambara groundnut (Vigna subterranea (L.) Verdcourt) seeds and screening for the production of aflatoxin B1 and B2

In Burkina Faso, Bambara groundnut is the second most important food legume after cowpea, especially in rural areas. However, this crop, due to certain conditions of production, storage or preservation is susceptible to be contaminated by potential mycotoxin producing fungi. The aim of this study was to evaluate the aflatoxinogenic capacity of Aspergillus flavus isolates isolated from Bambara groundnut seeds produced in Burkina Faso. Thus, 198 isolates of fungi belonging to section Flavi were isolated from 99 samples of Bambara groundnut seeds collected in the three agro-ecological zones of Burkina Faso. From the 198 isolates, 28 were identified as Aspergillus flavus. Then, we investigated their potential for aflatoxin B1 (AFB1) and B2 (AFB2) production by growing them on rice at 25°C for 7 days. AFB1 and AFB2 were extracted and quantified by liquid chromatography–mass spectrometry (LC-MS/MS). All of the strains (28) produced AFB1 at concentrations ranging from 46.987 μg kg–1 to 1080.320 μg kg–1. However, AFB2 was produced by 26 strains with concentrations ranging from 47.200 μg kg–1 to 1760.240 μg kg–1. Globally, most of the tested strains produced higher levels of AFB1 than AFB2. The results obtained point out the risk associated with post-harvest fungi and the need for the development of storage technics to control them, for food security.

Reviews of fungi and mycotoxins in Chinese dark tea.

The fermentation is the main process to form the unique flavor and health benefits of dark tea. Numerous studies have indicated that the microorganisms play a significant part in the fermentation process of dark tea. Dark tea has the quality of "The unique flavor grows over time," but unscientific storage of dark tea might cause infestation of harmful microorganisms, thereby resulting in the remaining of fungi toxins. Mycotoxins are regarded as the main contributor to the quality of dark tea, and its potential mycotoxin risk has attracted people's attention. This study reviews common and potential mycotoxins in dark tea and discusses the possible types of masked mycotoxins in dark tea. A summary of the potential risks of mycotoxins and masked mycotoxins in dark tea is presented, intending to provide a reference for the prevention and risk assessment of harmful fungi in dark tea.

Occurrence, identification, and decontamination of potential mycotoxins in fruits and fruit by‐products

AbstractThe incidence of aflatoxins, ochratoxin A, and patulin in fruits and processed fruit products has been ever more challenging and gained additional focus on ecofriendly mitigation strategies. The onset of these toxins is due to several factors involving insect attacks, agricultural practices, and climate change. Acute and chronic health hazards are clinically proven after consuming contaminated foodstuffs, even at lower concentrations of mycotoxins. Synergistic, masked, and substantial occurrence in fruit matrices increase their complexity in detection and detoxification; apparently, this article reviewed the available information on the occurrence of mycotoxins in several fruits and their products, focused on the conventional and advanced methods of identification, quantification, and decontamination techniques. Strengthening and implementing stringent international and national guidelines are required for impactful, tangible measures in the future. Nevertheless, controlling the mycotoxins in fruits will certainly be challenging for scientists. Therefore, more impactful technologies are still needed to eliminate the toxins at the threshold level of the food chain and ensure sustainable global food safety.

Identification of Lasiodiplodia pseudotheobromae Causing Leaf Blight Disease of Thaumatococcus daniellii (Benn.) Benth (Sweet Prayer Plant)

This study is aimed at isolating and identifying the common fungal pathogens causing leaf blight disease of Thaumatococcus daniellii known as the sweet prayer plant, using the molecular technique. It is a highly nutritional plant, used as laxatives, venom antidote, sedative and in the treatment of diabetes mellitus. Despite its global popularity owing to the usefulness of the leaves in food wrapping and packaging, it has been observed that the plants suffer severe leaf blight disease caused by fungal pathogens. Samples of leaves showing disease symptoms were collected from the Umuakali community in Omuma Local Government Area of Rivers State between June 2021 and October 2022. Fungal isolates were collected from leaves and morphologically identified. The DNA of the most common fungal isolate, SPP-01, was molecularly characterized using Internal Transcribed Spacer 1 (ITS-1) molecular markers. Sequences obtained were subjected to BLAST search in the GenBank database. The morphological results indicated that the SPP- 01 isolate was a Lasiodiplodia species. The molecular weight of the DNA of the isolate was over 550 Base Pairs. Based on sequence similarity, the DNA sequence of the isolate was 99% identical to Lasiodiplodia pseudotheobromae. A pathogenicity test of the isolated pathogen was carried out. Therefore, these findings showed that L. pseudotheobromae is the causal fungal pathogen of leaf blight disease of the sweet prayer plant. It is expected that this finding will promote the acquaintance of the fungal species associated with the sweet prayer plant and provide information for developing an effective disease management strategy for mitigating the losses caused by L. pseudotheobromae and also provide the basis for further study of potential mycotoxin effect of consuming disease leaves. To the best of our knowledge, this is the first report of molecular characterization of L. pseudotheobromae infesting sweet prayer plant in Rivers State.

Surface fungal diversity and several mycotoxin-related genes’ expression profiles during the Lunar Palace 365 experiment

BackgroundChinese Lunar Palace 1 (LP1) is a ground-based bio-regenerative life support system (BLSS) test bed integrating highly efficient plant cultivation, animal protein production, urine nitrogen recycling, and bioconversion of solid waste. To date, there has been no molecular method-based detailed investigation of the fungal community and mycotoxin potential in BLSS habitats. To ensure safe BLSS design for actual space missions, we analyzed the LP1 surface mycobiome and mycotoxin potential during the Lunar Palace 365 project through internal transcribed spacer region 1 (ITS1) amplicon sequencing and quantitative polymerase chain reaction (qPCR) with primers specific for idh, ver1, nor1, tri5, and ITS1.ResultsThe LP1 system exhibited significant differences in fungal community diversity compared to other confined habitats, with higher fungal alpha diversity and different community structures. Significant differences existed in the surface fungal communities of the LP1 habitat due to the presence of different occupant groups. However, there was no significant difference between fungal communities in the plant cabin with various occupants. Source tracker analysis shows that most of the surface fungi in LP1 originated from plants. Regardless of differences in occupants or location, there were no significant differences in mycotoxin gene copy number.ConclusionsOur study reveals that plants are the most crucial source of the surface fungal microbiome; however, occupant turnover can induce significant perturbations in the surface fungal community in a BLSS. Growing plants reduced fungal fluctuations, maintaining a healthy balance in the surface fungal microbiome and mycotoxin potential. Moreover, our study provides data important to (i) future risk considerations in crewed space missions with long-term residency, (ii) an optimized design and planning of a space mission that incorporates crew shifts and plant growth, and (iii) the expansion of our knowledge of indoor fungal communities with plant growth, which is essential to maintain safe working and living environments.CKJxDJEfgffQukT8cscD4AVideo

Impact of water management and geographic location on the physicochemical traits and fungal population of ‘Calabacita’ dried figs in Extremadura (Spain)

The traditional process of sun-drying figs involves a high risk of toxigenic mold contamination and, as a consequence, potential mycotoxin occurrence. In this study, the influence of the environmental conditions in the three main production areas of ‘Calabacita’ dried figs in Extremadura (Spain), more precisely Almoharín, Guadajira, and Guareña, on physicochemical traits and microbiological quality was evaluated. Simultaneously, the impact of water management, irrigated and rainfed conditions, in the Almoharín area was also determined. For this purpose, dried fig samples were collected in two consecutive seasons (2018 and 2019) at different drying steps, harvesting from the ground and after final drying under greenhouse conditions until the final moisture content was reached. All physicochemical parameters were significantly influenced by geographic location whereas water management had only a significant impact on firmness, total soluble solids and fruit size. Changes in moisture content and aw of dried figs from different geographic locations as well as water management modified yeast counts, while mold counts did not show significant changes. However, the mold population was complex, with 40 species identified, mainly belonging to Penicillium spp. (29.4%), Aspergillus spp. (24.5%), Cladosporium spp. (18.9%) and Alternaria spp. (17.3%). The occurrence of these mold species was strongly influenced by geographic location while the influence of water management was minimal. Furthermore, a substantial co-occurrence of samples contaminated with aflatoxin- and ochratoxin A-producing Aspergillus species was found. Of the total samples of dried figs analysed, 10.8% were contaminated with aflatoxins ranging from 0.1 to >70 ppb and 12.5% with ochratoxin A in the range from 10 to >70 ppb. The edaphoclimatic conditions specific to each geographic location set the physicochemical and microbiological quality of dried figs in Extremadura. In contrast, rainfed conditions had a limited impact beyond fruit size and higher level of AFs-producing mold under water stress. These findings are crucial to minimize the risks associated with the occurrence of toxigenic molds on dried figs.