ABSTRACT
Fusarium culmorum is a major wheat pathogen, and its secondary metabolites (mycotoxins) cause damage to plants, animals, and human health. In the era of sustainable agriculture, eco-friendly methods of prevention and control are constantly needed. The use of plant extracts as biocontrol agents has gained popularity as they are a source of active substances that play a crucial role in fighting against phytopathogens. This study evaluated the impact of Lamium album on wheat seed germination and seedling growth. In a pot experiment, the effect of L. album on wheat seedlings artificially inoculated with F. culmorum was evaluated by measuring seedling growth parameters, and by using chromatographic methods, ergosterol and mycotoxins levels were analyzed. The results showed that the phytotoxic effect of L. album flower extracts on wheat seed germination and seedling growth was concentration dependent. The radicle length was also reduced compared to the control; however, L. album did not significantly affect the dry weight of the radicle. A slight phytotoxic effect on seed germination was observed, but antifungal effects on artificially infected wheat seedlings were also confirmed with the reduction of ergosterol level and mycotoxins accumulation in the roots and leaves after 21 days of inoculation. F. culmorum DNA was identified in the control samples only. Overall, this study is a successful in planta study showing L. album flower extract protection of wheat against the pathogen responsible for Fusarium crown and root rot. Further research is essential to study the effects of L. album extracts on key regulatory genes for mycotoxin biosynthetic pathways.
ABSTRACT
The present study assessed the ability of Trichoderma to combat F. sporotrichioides, focusing on their antagonistic properties. Tests showed that Trichoderma effectively inhibited F. sporotrichioides mycelial growth, particularly with T. atroviride strains. In co-cultures on rice grains, Trichoderma almost completely reduced the biosynthesis of T-2 and HT-2 toxins by Fusarium. T-2 toxin-α-glucoside (T-2-3α-G), HT-2 toxin-α-glucoside (HT-2-3α-G), and HT-2 toxin-ß-glucoside (HT-2-3ß-G) were observed in the common culture medium, while these substances were not present in the control medium. The study also revealed unique metabolites and varying metabolomic profiles in joint cultures of Trichoderma and Fusarium, suggesting complex interactions. This research offers insights into the processes of biocontrol by Trichoderma, highlighting its potential as a sustainable solution for managing cereal plant pathogens and ensuring food safety.
Subject(s)
Fusarium , T-2 Toxin , T-2 Toxin/analogs & derivatives , Trichoderma , T-2 Toxin/metabolism , Fusarium/metabolism , Trichoderma/metabolism , Glycosylation , Edible Grain/metabolism , Glucosides/metabolismABSTRACT
The diversity of fungal strains is influenced by genetic and environmental factors, growth conditions and mycelium age, and the spectral features of fungal mycelia are associated with their biochemical, physiological, and structural traits. This study investigates whether intraspecific differences can be detected in two closely related entomopathogenic species, namely Cordyceps farinosa and Cordyceps fumosorosea, using ultraviolet A to shortwave infrared (UVA-SWIR) reflectance spectra. Phylogenetic analysis of all strains revealed a high degree of uniformity among the populations of both species. The characteristics resulting from variation in the species, as well as those resulting from the age of the cultures were determined. We cultured fungi on PDA medium and measured the reflectance of mycelia in the 350-2500 nm range after 10 and 17 days. We subjected the measurements to quadratic discriminant analysis (QDA) to identify the minimum number of bands containing meaningful information. We found that when the age of the fungal culture was known, species represented by a group of different strains could be distinguished with no more than 3-4 wavelengths, compared to 7-8 wavelengths when the age of the culture was unknown. At least 6-8 bands were required to distinguish cultures of a known species among different age groups. Distinguishing all strains within a species was more demanding: at least 10 bands were required for C. fumosorosea and 21 bands for C. farinosa. In conclusion, fungal differentiation using point reflectance spectroscopy gives reliable results when intraspecific and age variations are taken into account.
Subject(s)
Light , Mycelium , Discriminant Analysis , Phylogeny , Spectrum Analysis/methodsABSTRACT
BACKGROUND: Flavokawain B is one of the naturally occurring chalcones in the kava plant (Piper methysticum). It exhibits anticancer, anti-inflammatory and antimalarial properties. Due to its therapeutic potential, flavokawain B holds promise for the treatment of many diseases. However, due to its poor bioavailability and low aqueous solubility, its application remains limited. The attachment of a sugar unit impacts the stability and solubility of flavonoids and often determines their bioavailability and bioactivity. Biotransformation is an environmentally friendly way to improve the properties of compounds, for example, to increase their hydrophilicity and thus affect their bioavailability. Recent studies proved that entomopathogenic filamentous fungi from the genera Isaria and Beauveria can perform O-methylglycosylation of hydroxyflavonoids or O-demethylation and hydroxylation of selected chalcones and flavones. RESULTS: In the present study, we examined the ability of entomopathogenic filamentous fungal strains of Beauveria bassiana, Beauveria caledonica, Isaria farinosa, Isaria fumosorosea, and Isaria tenuipes to transform flavokawain B into its glycosylated derivatives. The main process occurring during the reaction is O-demethylation and/or hydroxylation followed by 4-O-methylglycosylation. The substrate used was characterized by low susceptibility to transformations compared to our previously described transformations of flavones and chalcones in the cultures of the tested strains. However, in the culture of the B. bassiana KCh J1.5 and BBT, Metarhizium robertsii MU4, and I. tenuipes MU35, the expected methylglycosides were obtained with high yields. Cheminformatic analyses indicated altered physicochemical and pharmacokinetic properties in the derivatives compared to flavokawain B. Pharmacological predictions suggested potential anticarcinogenic activity, caspase 3 stimulation, and antileishmanial effects. CONCLUSIONS: In summary, the study provided valuable insights into the enzymatic transformations of flavokawain B by entomopathogenic filamentous fungi, elucidating the structural modifications and predicting potential pharmacological activities of the obtained derivatives. The findings contribute to the understanding of the biocatalytic capabilities of these microbial cultures and the potential therapeutic applications of the modified flavokawain B derivatives.
Subject(s)
Chalcones , Flavones , Flavonoids/metabolism , Flavones/metabolism , BiotransformationABSTRACT
Lamium album is a medicinal flowering plant that is rich in bioactive compounds with various biological properties. Fusarium species, known for causing significant crop losses and mycotoxin contamination, pose threats to food safety and human health. While synthetic fungicides are commonly employed for fungal management, their environmental impact prompts the ongoing development of alternative methods. This study aimed to evaluate the efficacy of L. album flower extracts in inhibiting the in vitro growth and biosynthesis of mycotoxins by Fusarium culmorum and F. proliferatum strains. The extracts were obtained by supercritical fluid extraction using CO2 (SC-CO2). The effects of various concentrations (2.5, 5, 7.5, and 10%) were assessed on a potato dextrose agar (PDA) medium using the "poisoning" technique. L. album flower extracts reduced mycelium growth by 0 to 30.59% for F. culmorum and 27.71 to 42.97% for F. proliferatum. Ergosterol content was reduced by up to 88.87% for F. culmorum and 93.17% for F. proliferatum. Similarly, the amounts of synthesized mycotoxins produced by both strains were also lower compared to control cultures. These findings are a preliminary phase for further in vivo tests planned to determine the fungistatic effect of L. album flower extracts on cereal substrates as seedlings incubated in controlled environments and under field conditions. Their phytotoxicity and biological stability, as well as the possibility of formulating a bio-preparation to protect cereals against Fusarium infections, will be evaluated.
Subject(s)
Fungicides, Industrial , Fusarium , Mycotoxins , Humans , Carbon Dioxide , Mycotoxins/analysis , Edible Grain/chemistry , Fungicides, Industrial/pharmacologyABSTRACT
Quercetin is the most abundant flavonoid in food products, including berries, apples, cauliflower, tea, cabbage, nuts, onions, red wine and fruit juices. It exhibits various biological activities and is used for medical applications, such as treating allergic, inflammatory and metabolic disorders, ophthalmic and cardiovascular diseases, and arthritis. However, its low water solubility may limit quercetin's therapeutic potential. One method of increasing the solubility of active compounds is their coupling to polar molecules, such as sugars. The attachment of a glucose unit impacts the stability and solubility of flavonoids and often determines their bioavailability and bioactivity. Entomopathogenic fungi are biocatalysts well known for their ability to attach glucose and its 4-O-methyl derivative to bioactive compounds, including flavonoids. We investigated the ability of cultures of entomopathogenic fungi belonging to Beauveria, Isaria, Metapochonia, Lecanicillium and Metarhizium genera to biotransform quercetin. Three major glycosylation products were detected: (1), 7-O-ß-D-(4â³-O-methylglucopyranosyl)-quercetin, (2) 3-O-ß-D-(4â³-O-methylglucopyranosyl)-quercetin and (3) 3-O-ß-D-(glucopyranosyl)-quercetin. The results show evident variability of the biotransformation process, both between strains of the tested biocatalysts from different species and between strains of the same species. Pharmacokinetic and pharmacodynamic properties of the obtained compounds were predicted with the use of cheminformatics tools. The study showed that the obtained compounds may have applications as effective modulators of intestinal flora and may be stronger hepato-, cardio- and vasoprotectants and free radical scavengers than quercetin.
Subject(s)
Hypocreales , Quercetin , Quercetin/pharmacology , Quercetin/metabolism , Glycosylation , Flavonoids/pharmacology , Hypocreales/metabolism , Antioxidants/pharmacology , Antioxidants/metabolism , Fungi/metabolismABSTRACT
This study evaluated the ability of selected strains of Trichoderma viride, T. viridescens, and T. atroviride to inhibit mycelium growth and the biosynthesis of mycotoxins deoxynivalenol (DON), nivalenol (NIV), zearalenone (ZEN), α-(α-ZOL) and ß-zearalenol (ß-ZOL) by selected strains of Fusarium culmorum and F. cerealis. For this purpose, an in vitro experiment was carried out on solid substrates (PDA and rice). After 5 days of co-culture, it was found that all Trichoderma strains used in the experiment significantly inhibited the growth of Fusarium mycelium. Qualitative assessment of pathogen-antagonist interactions showed that Trichoderma colonized 75% to 100% of the medium surface (depending on the species and strain of the antagonist and the pathogen) and was also able to grow over the mycelium of the pathogen and sporulate. The rate of inhibition of Fusarium mycelium growth by Trichoderma ranged from approximately 24% to 66%. When Fusarium and Trichoderma were co-cultured on rice, Trichoderma strains were found to inhibit DON biosynthesis by about 73% to 98%, NIV by about 87% to 100%, and ZEN by about 12% to 100%, depending on the pathogen and antagonist strain. A glycosylated form of DON was detected in the co-culture of F. culmorum and Trichoderma, whereas it was absent in cultures of the pathogen alone, thus suggesting that Trichoderma is able to glycosylate DON. The results also suggest that a strain of T. viride is able to convert ZEN into its hydroxylated derivative, ß-ZOL.
Subject(s)
Fusarium , Mycotoxins , Oryza , Trichoderma , Trichothecenes , Zearalenone , Zearalenone/pharmacologyABSTRACT
BACKGROUND: Decision-making skills are considered crucial life skills that condition proper social functioning within groups (i.e., support authentic leadership skills and increasing one's chances of success and wellbeing in life). Nonetheless, the number of scientific papers addressing the role of life skills in developing authentic leadership skills in public health students is limited. The aim of the present study was to develop a theoretical model to determine the role of selected life skills in developing authentic leadership skills in public health students. METHODS: The study was conducted from January 16 through February 28, 2018. In total, 653 students undertaking in-service training in Master's degree programs qualified for the study, and complete data sets were obtained from 329 students (response rate 50.38%). The data were collected by means of a paper questionnaire. Four research tools were used in the study: The Authentic Leadership Self-Assessment Questionnaire, The Moral Foundations Questionnaire, The General Self-Efficacy Scale, and The Youth Leadership Life Skills Development Scale. RESULTS: Two subgroups were identified among the public health students in the study: 1) the extra life skills training group (N = 113) and 2) the no extra life skills training group (N = 216). Both groups of study participants did not differ significantly in terms of age (M (SD): 25.0 (3.89) vs. 25.0 (3.66); t = 0.068, P = 0.946). On the other hand, clear differences were observed in the case of the respondents' participation in voluntary service. The respondents from the extra life skills training group declared participation in voluntary activities less frequently than the respondents from the second identified group (48.7 vs. 31.9%). CONCLUSIONS: A verified theoretical model showed that course aimed at strengthening authentic leadership competences should be modular, should focus on self-improvement and critical reflection, and should be spread over time to enable and encourage each participant to grow and flourish at their own pace.
Subject(s)
Leadership , Students, Public Health , Adolescent , Attitude , Cross-Sectional Studies , Humans , PolandABSTRACT
The objectives of this research were to obtain the extracts of lemon balm (Melissa officinalis) using supercritical CO2 (SC-CO2) and methanol as co-solvent and evaluate the antifungal activity of those extracts against two selected strains of Fusarium species (Fusarium culmorum and Fusarium proliferatum). The extraction conditions were set at 40 and 60 °C and 250 bar. The obtained extracts were characterized in terms of antifungal activity on potato dextrose agar media (PDA). The results showed that the extraction parameters had different effects on mycelium growth and mycotoxins biosynthesis reduction. All studied lemon balm extracts (1, 2.5, 5, 7.5, and 10%) inhibited the growth of F. proliferatum and F. culmorum mycelia compared to the control. The lemon balm extracts significantly reduced ergosterol content and synthesized mycotoxins in both tested strains. These findings support the antifungal activity of lemon balm extracts against F. proliferatum and F. culmorum. However, more research on other Fusarium species is needed, as well as in vivo applications, before considering lemon balm extracts as a natural alternative to synthetic fungicides.
Subject(s)
Fusarium , Melissa , Mycotoxins , Antifungal Agents/pharmacology , Carbon Dioxide , Mycotoxins/pharmacology , Plant Extracts/pharmacologyABSTRACT
Fusarium head blight (FHB) caused by pathogenic species of Fusarium fungi is one of the most important diseases of cereal plants and a factor contributing to losses in plant production. The growth of FHB-associated species is often accompanied by biosynthesis of secondary metabolitesâmycotoxins, which serve as a virulence factor. The aim of the study was to evaluate the ratios between deoxynivalenol (DON) and nivalenol (NIV) and their derivatives in the ears of six cultivars of winter wheat with varying resistance to FHB, taking into account a range of factors (weather conditions, location, cultivar, and year) after inoculation with Fusarium culmorum, during a 3 year field experiment, 2018-2020. The presence of toxins in the ears was measured within 21 days of inoculation. The toxins were found in the ears as soon as on the third day from the start of the experiment, whereas relative humidity higher than 80% was a decisive factor for FHB incidence. All wheat cultivars showed the ability to biotransform DON and NIV present in the ears to glucosides, that is, deoxynivalenol-3-glucoside (DON-3G) and nivalenol-3-glucoside (NIV-3G). The levels of these metabolites showed significant correlation with the levels of their basic analogues. In most cases, higher levels of DON and NIV in wheat ears and higher levels of their metabolites were observed, but the relative levels of DON-3G/DON and NIV-3G/NIV at relatively high levels of toxins were lower compared to the ear samples with relatively low toxin levels. The presented results are the first studies, which systematically correlate a variety of wheat cultivars with their extent to glucosylate trichothecenes.
Subject(s)
Fusarium , Mycotoxins , Trichothecenes , Fusarium/metabolism , Glucosides/metabolism , Mycotoxins/metabolism , Plant Diseases/microbiology , Trichothecenes/metabolism , Triticum/metabolismABSTRACT
Fusarium species present ubiquitously in the environment are capable of infecting a wide range of plant species. They produce several mycotoxins targeted to weaken the host plant. While infecting some resistant plants, the host can alter the expression of toxin-related genes and accumulate no/very low amounts of mycotoxins. The ability of the host plant to modulate the biosynthesis of these toxins is entirely depending on the secondary metabolites produced by the plant, often as a part of systemic acquired resistance (SAR). A major role plays in the family of metabolites called phenyl propanoids, consisting of thousands of natural products, synthesized from the phenylalanine or tyrosine amino acids through a cascade of enzymatic reactions. They are also famous for inhibiting or limiting infection through their antioxidant characteristics. The current study was aimed at identifying the differentially expressed secondary metabolites in resistant (Sokolik) and susceptible (Santana) cultivars of pea (Pisum sativum L.) and understanding their roles in the growth and mycotoxin biosynthesis of two different Fusarium species. Although metabolites such as coumarin, spermidine, p-coumaric acid, isoorientin, and quercetin reduced the growth of the pathogen, a higher level of p-coumaric acid was found to enhance the growth of F. proliferatum strain PEA1. It was also noticeable that the growth of the pathogen did not depend on their ability to produce mycotoxins, as all the metabolites were able to highly inhibit the biosynthesis of fumonisin B1 and beauvericin.
ABSTRACT
Fusarium species are common plant pathogens that cause several important diseases. They produce a wide range of secondary metabolites, among which mycotoxins and extracellular cell wall-degrading enzymes (CWDEs) contribute to weakening and invading the host plant successfully. Two species of Fusarium isolated from peas were monitored for their expression profile of three cell wall-degrading enzyme coding genes upon culturing with extracts from resistant (Sokolik) and susceptible (Santana) pea cultivars. The extracts from Santana induced a sudden increase in the gene expression, whereas Sokolik elicited a reduced expression. The coherent observation was that the biochemical profile of the host plant plays a major role in regulating the fungal gene expression. In order to uncover the fungal characteristics in planta, both pea cultivars were infected with two strains each of F. proliferatum and F. oxysporum on the 30th day of growth. The enzyme activity assays from both roots and rhizosphere indicated that more enzymes were used for degrading the cell wall of the resistant host compared to the susceptible host. The most commonly produced enzymes were cellulase, ß-glucosidase, xylanase, pectinase and lipase, where the pathogen selectively degraded the components of both the primary and secondary cell walls. The levels of beauvericin accumulated in the infected roots of both cultivars were also monitored. There was a difference between the levels of beauvericin accumulated in both the cultivars, where the susceptible cultivar had more beauvericin than the resistant one, showing that the plants susceptible to the pathogen were also susceptible to the toxin accumulation.
Subject(s)
Fusarium/pathogenicity , Mycotoxins/genetics , Pisum sativum/microbiology , Plant Diseases/genetics , Fusarium/genetics , Host-Pathogen Interactions/genetics , Pisum sativum/enzymology , Plant Diseases/microbiology , Plant Roots/growth & development , Plant Roots/microbiologyABSTRACT
The study aimed to compare the yeast species diversity in the specific environment of dishwashers, taking into account the potential risk for users. Yeasts were isolated from ten dishwashers and from tap water supplied to the appliances. Samples were collected for mycological analyses at the beginning of each month, from February to May 2016. Four dishwasher sites (rubber seals, detergent dispensers, sprinklers, and water drains) were analyzed. The microfungi were identified by the standard procedures applied in mycological diagnostics. To confirm species identification, molecular analysis was performed based on the sequences of the D1/D2 region. The presence of microfungi was detected in 70% of the investigated appliances. Rubber seals, detergent dispensers, and water drains were the most frequently colonized elements. Thirty-five yeast strains were isolated in this study, of which twenty-seven were obtained from dishwashers and eight from tap water. The strains belonged to six genera and six species (Candida parapsilosis, Clavispora lusitaniae, Dipodascus capitatus, Exophiala dermatitidis, Meyerozyma guilliermondii, and Rhodotorula mucilaginosa). Most of the strains came from rubber seals. In this way, it was demonstrated that the dishwashers' condition is sufficient as an ecological niche for microfungi.
ABSTRACT
Most of the fungi from the Fusarium genus are pathogenic to cereals, vegetables, and fruits and the products of their secondary metabolism mycotoxins may accumulate in foods and feeds. Non-ribosomal cyclodepsipeptides are one of the main mycotoxin groups and include beauvericins (BEAs), enniatins (ENNs), and beauvenniatins (BEAEs). When ingested, even small amounts of these metabolites significantly affect human and animal health. On the other hand, in view of their antimicrobial activities and cytotoxicity, they may be used as components in drug discovery and processing and are considered as suitable candidates for anti-cancer drugs. Therefore, it is crucial to expand the existing knowledge about cyclodepsipeptides and to search for new analogues of these compounds. The present manuscript aimed to highlight the extensive variability of cyclodepsipeptides by describing chemistry, biosynthesis, and occurrence of BEAs, ENNs, and BEAEs in foods and feeds. Moreover, the co-occurrence of Fusarium species was compared to the amounts of toxins in crops, vegetables, and fruits from different regions of the world.
Subject(s)
Depsipeptides , Fusarium , Mycotoxins , Animal Feed/analysis , Depsipeptides/analysis , Depsipeptides/biosynthesis , Depsipeptides/chemistry , Food Contamination/analysis , Mycotoxins/analysis , Mycotoxins/biosynthesis , Mycotoxins/chemistryABSTRACT
Beauvericin (BEA) is a cyclodepsipeptide mycotoxin, showing insecticidal, antibiotic and antimicrobial activities, as well as inducing apoptosis of cancer cell lines. BEA can be produced by multiple fungal species, including saprotrophs, plant, insect and human pathogens, particularly belonging to Fusarium, Beauveria and Isaria genera. The ability of Trichoderma species to produce BEA was until now uncertain. Biosynthesis of BEA is governed by a non-ribosomal peptide synthase (NRPS), known as beauvericin synthase (BEAS), which appears to present considerable divergence among different fungal species. In the present study we compared the production of beauvericin among Fusarium and Trichoderma strains using UPLC methods. BEAS fragments were sequenced and analyzed to examine the level of the gene's divergence between these two genera and confirm the presence of active BEAS copy in Trichoderma. Seventeen strains of twelve species were studied and phylogenetic analysis showed distinctive grouping of Fusarium and Trichoderma strains. The highest producers of beauvericin were F. proliferatum and F. nygamai. Trichoderma strains of three species (T. atroviride, T. viride, T. koningiopsis) were minor BEA producers. The study showed beauvericin production by Fusarium and Trichoderma species and high variance of the non-ribosomal peptide synthase gene among fungal species from the Hypocreales order.
ABSTRACT
The article presents a case of sudden death of a 56-year-old woman at the workplace, caused by a very rare primary cardiac tumor. The patient's family reported a crime to the prosecutor's office suggesting participation of third parties in causing the death or malpractice in physical examinations before the death. A review of clinical data concerning cardiac angiosarcoma, available in electronic databases (e.g., Web of Science, PubMed), was presented, which could be useful in the practice of occupational medicine specialists. A legal analysis of potential claims to occupational medicine specialist in the case of failure to recognize primary cardiac tumors was also included in the article. Med Pr. 2020;71(6):757-64.
Subject(s)
Hemangiosarcoma/diagnosis , Hemangiosarcoma/mortality , Malpractice/legislation & jurisprudence , Occupational Medicine/legislation & jurisprudence , Occupational Medicine/standards , Physical Examination/mortality , Physical Examination/standards , Workplace/legislation & jurisprudence , Female , Heart Neoplasms/diagnosis , Heart Neoplasms/mortality , Heart Neoplasms/physiopathology , Hemangiosarcoma/physiopathology , Humans , Malpractice/statistics & numerical data , Middle Aged , Poland , Workplace/statistics & numerical dataABSTRACT
Fungi from the Hypocreales order synthesize a range of toxic non-ribosomal cyclic peptides with antimicrobial, insecticidal and cytotoxic activities. Entomopathogenic Beauveria, Isaria and Cordyceps as well as phytopathogenic Fusarium spp. are known producers of beauvericins (BEAs), beauvenniatins (BEAEs) or enniatins (ENNs). The compounds are synthesized by beauvericin/enniatin synthase (BEAS/ESYN1), which shows significant sequence divergence among Hypocreales members. We investigated ENN, BEA and BEAE production among entomopathogenic (Beauveria, Cordyceps, Isaria) and phytopathogenic (Fusarium) fungi; BEA and ENNs were quantified using an LC-MS/MS method. Phylogenetic analysis of partial sequences of putative BEAS/ESYN1 amplicons was also made. Nineteen fungal strains were identified based on sequence analysis of amplified ITS and tef-1α regions. BEA was produced by all investigated fungi, with F. proliferatum and F. concentricum being the most efficient producers. ENNs were synthesized mostly by F. acuminatum, F. avenaceum and C. confragosa. The phylogeny reconstruction suggests that ancestral BEA biosynthesis independently diverged into biosynthesis of other compounds. The divergent positioning of three Fusarium isolates raises the possibility of parallel acquisition of cyclic depsipeptide synthases in ancient complexes within Fusarium genus. Different fungi have independently evolved NRPS genes involved in depsipeptide biosynthesis, with functional adaptation towards biosynthesis of overlapping yet diversified metabolite profiles.
ABSTRACT
Investigating the in vitro fumonisin biosynthesis and the genetic structure of Fusarium verticillioides populations can provide important insights into the relationships between strains originating from various world regions. In this study, 90 F. verticillioides strains isolated from maize in five Mediterranean countries (Italy, Spain, Tunisia, Egypt and Iran) were analyzed to investigate their ability to in vitro biosynthesize fumonisin B1, fumonisin B2 and fumonisin B3 and to characterize their genetic profile. In general, 80% of the analyzed strains were able to biosynthesize fumonisins (range 0.03-69.84 µg/g). Populations from Italy, Spain, Tunisia and Iran showed a similar percentage of fumonisin producing strains (>90%); conversely, the Egyptian population showed a lower level of producing strains (46%). Significant differences in fumonisin biosynthesis were detected among strains isolated in the same country and among strains isolated from different countries. A portion of the divergent FUM1 gene and of intergenic regions FUM6-FUM7 and FUM7-FUM8 were sequenced to evaluate strain diversity among populations. A high level of genetic uniformity inside the populations analyzed was detected. Apparently, neither geographical origin nor fumonisin production ability were correlated to the genetic diversity of the strain set. However, four strains from Egypt differed from the remaining strains.
ABSTRACT
OBJECTIVES: A rare case of a suicidal use of gases from the car exhaust system of the car petrol engine in an open space is presented. CLINICAL PRESENTATION AND INTERVENTION: To verify suicidal intent of poisoning, an experimental reconstruction of the crime scene was performed. This demonstrated that appropriately long exposure to carbon monoxide with unfavorable weather conditions can cause acute carbon monoxide poisoning in an open space. CONCLUSIONS: This case was studied to observe the pattern of fatal carbon monoxide poisoning in an open space. This might be helpful for forensic medicine, emergency medicine, and occupational medicine.
Subject(s)
Carbon Monoxide Poisoning/diagnosis , Suicide , Autopsy , Forensic Medicine , Humans , Male , Middle Aged , Motor VehiclesABSTRACT
Beauvericin is a depsipeptide mycotoxin. The production of several beauvericin analogues has previously been shown among various genera among Hypocreales fungi. This includes so-called beauvenniatins, in which one or more N-methyl-phenylalanine residues is exchanged with other amino acids. In addition, a range of "unnatural" beauvericins has been prepared by a precursor addition to growth medium. Our aim was to get insight into the natural production of beauvericin analogues among different Hypocreales fungi, such as Fusarium and Isaria spp. In addition to beauvericin, we tentatively identified six earlier described analogues in the extracts; these were beauvericin A and/or its structural isomer beauvericin F, beauvericin C, beauvericin J, beauvericin D, and beauvenniatin A. Other analogues contained at least one additional oxygen atom. We show that the additional oxygen atom(s) were due to the presence of one to three N-methyl-tyrosine moieties in the depsipeptide molecules by using different liquid chromatographyâ»mass spectrometry-based approaches. In addition, we also tentatively identified a beauvenniatin that contained N-methyl-leucine, which we named beauvenniatin L. This compound has not been reported before. Our data show that N-methyl-tyrosine containing beauvericins may be among the major naturally produced analogues in certain fungal strains.