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Applied and Environmental Microbiology Sep 2015Submicronic fungal fragments have been observed in in vitro aerosolization experiments. The occurrence of these particles has therefore been suggested to contribute to...
Submicronic fungal fragments have been observed in in vitro aerosolization experiments. The occurrence of these particles has therefore been suggested to contribute to respiratory health problems observed in mold-contaminated indoor environments. However, the role of submicronic fragments in exacerbating adverse health effects has remained unclear due to limitations associated with detection methods. In the present study, we report the development of an indirect immunodetection assay that utilizes chicken polyclonal antibodies developed against spores from Aspergillus versicolor and high-resolution field emission scanning electron microscopy (FESEM). Immunolabeling was performed with A. versicolor fragments immobilized and fixed onto poly-l-lysine-coated polycarbonate filters. Ninety percent of submicronic fragments and 1- to 2-μm fragments, compared to 100% of >2-μm fragments generated from pure freeze-dried mycelial fragments of A. versicolor, were positively labeled. In proof-of-concept experiments, air samples collected from moldy indoor environments were evaluated using the immunolabeling technique. Our results indicated that 13% of the total collected particles were derived from fungi. This fraction comprises 79% of the fragments that were detected by immunolabeling and 21% of the spore particles that were morphologically identified. The methods reported in this study enable the enumeration of fungal particles, including submicronic fragments, in a complex heterogeneous environmental sample.
Topics: Aspergillus; Immunoassay; Microscopy, Electron, Scanning; Particle Size; Spores, Fungal
PubMed: 26092450
DOI: 10.1128/AEM.00929-15 -
Antimicrobial Agents and Chemotherapy Mar 2020The rise of Gram-negative pathogens expressing metallo-β-lactamases (MBLs) is a growing concern, threatening the efficacy of β-lactam antibiotics, in particular, the...
The rise of Gram-negative pathogens expressing metallo-β-lactamases (MBLs) is a growing concern, threatening the efficacy of β-lactam antibiotics, in particular, the carbapenems. There are no inhibitors of MBLs in current clinical use. Aspergillomarasmine A (AMA) is an MBL inhibitor isolated from with the ability to rescue meropenem activity in MBL-producing bacteria both and Here, we systematically explored the pairing of AMA with six β-lactam antibiotic partners against 19 MBLs from three subclasses (B1, B2, and B3). Cell-based assays performed with and showed that bacteria producing NDM-1 and VIM-2 of subclass B1 were the most susceptible to AMA inhibition, whereas bacteria producing CphA2 and AIM-1 of subclasses B2 and B3, respectively, were the least sensitive. Intracellular antibiotic accumulation assays and enzyme assays demonstrated that the efficacy of AMA/β-lactam combinations did not correlate with outer membrane permeability or drug efflux. We determined that the optimal β-lactam partners for AMA are the carbapenem antibiotics and that the efficacy of AMA is linked to the Zn affinity of specific MBLs.
Topics: Anti-Bacterial Agents; Aspartic Acid; Aspergillus; Carbapenems; Cell Membrane Permeability; Escherichia coli; Klebsiella pneumoniae; Microbial Sensitivity Tests; beta-Lactam Resistance; beta-Lactamase Inhibitors; beta-Lactamases
PubMed: 31932375
DOI: 10.1128/AAC.01386-19 -
Mycobiology 2021Despite recent studies, relatively few are known about the diversity of fungal communities in the deep Atlantic Ocean. In this study, we investigated the diversity of...
Despite recent studies, relatively few are known about the diversity of fungal communities in the deep Atlantic Ocean. In this study, we investigated the diversity of fungal communities in 15 different deep-sea sediments from the South Atlantic Ocean with a culture-dependent approach followed by phylogenetic analysis of ITS sequences. A total of 29 fungal strains were isolated from the 15 deep-sea sediments. These strains belong to four fungal genera, including , , , and . , accounting for 44.8% of the total fungal isolates, was a dominant genus. The antiaflatoxigenic activity of these deep-sea fungal isolates was studied. Surprisingly, most of the strains showed moderate to strong antiaflatoxigenic activity. Four isolates, belonging to species of , , and , could completely inhibit not only the mycelial growth of mutant strain NFRI-95, but also the aflatoxin production. To our knowledge, this is the first report to investigate the antiaflatoxigenic activity of culturable deep-sea fungi. Our results provide new insights into the community composition of fungi in the deep South Atlantic Ocean. The high proportion of strains that displayed antiaflatoxigenic activity demonstrates that deep-sea fungi from the Atlantic Ocean are valuable resources for mining bioactive compounds.
PubMed: 37970182
DOI: 10.1080/12298093.2020.1871175 -
Materials (Basel, Switzerland) Aug 2019The aim of this study was to develop new sulfur-copolymer concrete composites using waste compounds that have good mechanical characteristics and show a resistance to...
The aim of this study was to develop new sulfur-copolymer concrete composites using waste compounds that have good mechanical characteristics and show a resistance to biocorrosion. The comonomers used to synthesize the sulfur-organic copolymers were-90 wt. % sulfur; 5 wt. % dicyclopentadiene (DCPD); 5 wt. % organic monomers, styrene (SDS), 1-decene (SDD), turpentine (SDT), and furfural (SDF). The concrete composites based on sulfur-organic copolymers were filled with aggregates, sand, gravel, as well as additives and industrial waste such as fly ash or phosphogypsum. The sulfur-organic copolymers were found to be chemically stable (softening temperature, thermal stability, melting temperature, amount of recrystallized sulfur, and shore D hardness). Partial replacement of DCPD with other organic comonomers did not change the thermal stability markedly but did make the copolymers more elastic. However, the materials became significantly stiffer after repeated melting. All the tested copolymers were found to be resistant to microbial corrosion. The highest resistance was exhibited by the SDS-containing polymer, while the SDF polymer exhibited the greatest change due to the activity of the microorganisms (FTIR analysis and sulfur crystallization). The concrete composites with sulfur-organic copolymers containing DCPD, SDS, SDF, fly ash, and phosphogypsum were mechanically resistant to compression and stretching, had low water absorbance, and were resistant to factors, such as temperature and salt. Resistance to freezing and thawing (150 cycles) was not confirmed. The concrete composites with sulfur-organic copolymers showed resistance to bacterial growth and acid activity during 8 weeks of incubation with microorganisms. No significant structural changes were observed in the SDS composites after incubation with bacteria, whereas composites containing SDF showed slight changes (FTIR and microscopic analysis). The concrete composite containing sulfur, DCPD, SDS, sand, gravel, and fly ash was the most resistant to microbiological corrosion, based on the metabolic activity of the bacteria and the production of ergosterol by the molds after eight weeks of incubation. It was found that was the first of the acidifying bacteria to colonize the sulfur concrete, decreasing the pH of the environment. The molds , and were able to grow on the surface of the tested composites only in the presence of an organic carbon source (glucose). During incubation, they produced organic acids and acidified the environment. However, no morphological changes in the concretes were observed suggesting that sulfur-organic copolymers containing styrene could be used as engineering materials or be applied as binders in sulfur-concretes.
PubMed: 31443281
DOI: 10.3390/ma12162602 -
International Journal of Molecular... Feb 2023Scientific examination of the heart of Blessed Pauline Jaricot-a French missionary figure-was carried out in 2022. As tandem mass spectrometry proteotyping has proven to...
Scientific examination of the heart of Blessed Pauline Jaricot-a French missionary figure-was carried out in 2022. As tandem mass spectrometry proteotyping has proven to be valuable to obtain the broad taxonomic repertoire of a given sample without any a priori information, we aimed at exploring the conditions of preservation of the relics and possible conditions of death. Metaproteomics and high-resolution microtomography imaging approaches were combined. A dataset comprising 6731 high-resolution MS/MS spectra was acquired and 968 of these spectra could be assigned to specific peptidic biomolecules. Based on the taxonomical information encompassed by the identified peptide sequences, 5 phyla were identified amongst eukaryota (94% of the biomass): Ascomycota (55%), with the species , and , corresponding to expected cadaverous fungal flora; Chordata (42%), represented by a unique species, ; Streptophyta (3%); and Arthropoda (traces). Bacteria (6% of the biomass) were poorly represented. No trace of embalming substance could be retrieved, nor any pathogens. Imaging evidenced no heart defect nor embalming traces. No evidence that was inconsistent with natural and spontaneous conservation could be retrieved. This study prefigures the power of modern molecular techniques such as paleoproteotyping coupled to microtomography to gain insight into historical relics.
Topics: Humans; Embalming; Tandem Mass Spectrometry; Heart; Heart Defects, Congenital; Bacteria
PubMed: 36769339
DOI: 10.3390/ijms24033011 -
Microorganisms Dec 2020The secretion of metabolites in guttation droplets by indoor moulds is not well documented. This study demonstrates the guttation of metabolites by actively growing...
The secretion of metabolites in guttation droplets by indoor moulds is not well documented. This study demonstrates the guttation of metabolites by actively growing common indoor moulds. Old and fresh biomasses of indoor isolates of , , , , , sp. and sp. were compared. Metabolic activity indicated by viability staining and guttation of liquid droplets detected in young (<3 weeks old) biomass were absent in old (>6 months old) cultures consisting of dehydrated hyphae and dormant conidia. Fresh (<3 weeks old) biomasses were toxic more than 10 times towards mammalian cell lines (PK-15 and MNA) compared to the old dormant, dry biomasses, when calculated per biomass wet weight and per conidial particle. Surfactant activity was emitted in exudates from fresh biomass of , sp. and sp. Surfactant activity was also provoked by fresh conidia from and sp. strains. Water repealing substances were emitted by cultures of , and strains. The metabolic state of the indoor fungal growth may influence emission of liquid soluble bioreactive metabolites into the indoor air.
PubMed: 33297485
DOI: 10.3390/microorganisms8121940 -
Journal of Fungi (Basel, Switzerland) Mar 2023Potential markers were sought to diagnose mold hypersensitivity. Indoor air condensed water and human macrophage THP-1 test were applied to evaluate the buildings....
Potential markers were sought to diagnose mold hypersensitivity. Indoor air condensed water and human macrophage THP-1 test were applied to evaluate the buildings. Basophil activation tests (BAT) were conducted and mold-specific immunoglobulins (IgE, IgG, IgA, and IgD) were measured in study subjects' serum and feces. Exposed subjects reported markedly more symptoms from occupational air than controls. Basophils from exposed subjects died/lost activity at 225 times lower concentrations of toxic extracts from the target building than recommended in the common BAT protocol. Fecal IgG and IgD levels against and produced receiver operating curves (ROC) of 0.928 and 0.916, respectively, when plotted against the inflammation marker MRP8/14. Assaying serum immunoglobulin concentrations against the toxic from another building, a test control, did not differentiate study individuals. However, if liver metabolism produced the same core molecule from other strains, this would explain the increased response in fecal immunoglobulins in the exposed. The altered immunoglobulin values in the samples of exposed when compared to controls revealed the route of mold exposure. The toxicity of indoor air condensed water samples, BAT and serology confirmed the severity of symptoms in the target building's employees, supporting earlier findings of toxicity in this building.
PubMed: 36983500
DOI: 10.3390/jof9030332 -
Mediated Green Synthesis of Iron Oxide (FeO) Nanoparticles and Their Diverse In Vitro Bioactivities.Molecules (Basel, Switzerland) Feb 2023Iron oxide nanoparticles (FeO-NPs) were synthesized using extract as strong reducing and capping agents. The synthesized iron oxide nanoparticles IONPs were...
Iron oxide nanoparticles (FeO-NPs) were synthesized using extract as strong reducing and capping agents. The synthesized iron oxide nanoparticles IONPs were characterized by UV-visible spectroscopy, Fourier transform infrared (FTIR), X-ray diffractive analysis (XRD), scanning electron microscope (SEM), and Energy dispersive X-ray spectroscopy (EDX). IONPs synthesis was confirmed by UV-visible spectroscopy by observing the peak at 471 nm. Furthermore, different in vitro biological assays, which showed important therapeutic potentials, were performed. Antimicrobial assay of biosynthesized IONPs was performed against four different Gram-positive and Gram-negative bacterial strains. was found to be the least suspected strain (MIC: 35 µg/mL), and was found to be the most suspected strain (MIC: 14 µg/mL). The maximum antifungal assay was observed for (MIC: 27 µg mL). The cytotoxic assay of IONPs was also studied using a brine shrimp cytotoxicity assay, and LD value was reported as 47 µg/mL. In toxicological evaluation, IONPs was found to be biologically compatible to human RBCs (IC: >200 µg/mL). The antioxidant assay, DPPH 2,2-diphenyl-1-picrylhydrazyly was recorded at 73% for IONPs. In conclusion, IONPs revealed great biological potential and can be further recommended for in vitro and in vivo therapeutic purposes.
Topics: Humans; Escherichia coli; Metal Nanoparticles; Antifungal Agents; Spectroscopy, Fourier Transform Infrared; Anti-Bacterial Agents; Plant Extracts; X-Ray Diffraction; Microbial Sensitivity Tests
PubMed: 36903337
DOI: 10.3390/molecules28052091 -
Toxins Dec 2016The aim of this study was to investigate in vitro and model the effect of temperature (T) and water activity () conditions on growth and toxin production by some...
The aim of this study was to investigate in vitro and model the effect of temperature (T) and water activity () conditions on growth and toxin production by some toxigenic fungi signaled in cheese. , , , , , , , were considered they were grown under different T (0-40 °C) and (0.78-0.99) regimes. The highest relative growth occurred around 25 °C; all the fungi were very susceptible to and 0.99 was optimal for almost all species (except for , = 0.96). The highest toxin production occurred between 15 and 25 °C and 0.96-0.99 . Therefore, during grana cheese ripening, managed between 15 and 22 °C, ochratoxin A (OTA), penitrem A (PA), roquefortine-C (ROQ-C) and mycophenolic acid (MPA) are apparently at the highest production risk. Bete and logistic function described fungal growth under different T and regimes well, respectively. Bete function described also STC, PA, ROQ-C and OTA production as well as function of T. These models would be very useful as starting point to develop a mechanistic model to predict fungal growth and toxin production during cheese ripening and to help advising the most proper setting of environmental factors to minimize the contamination risk.
Topics: Aspergillus; Cheese; Food Contamination; Food Microbiology; Heterocyclic Compounds, 4 or More Rings; Indoles; Models, Theoretical; Mycophenolic Acid; Mycotoxins; Ochratoxins; Penicillium; Piperazines; Temperature; Water
PubMed: 28029129
DOI: 10.3390/toxins9010004 -
Asian-Australasian Journal of Animal... Jun 2020This study was conducted to determine the composition and diversity of the fungal flora at various control points in cheese ripening rooms of 10 dairy farms from six...
OBJECTIVE
This study was conducted to determine the composition and diversity of the fungal flora at various control points in cheese ripening rooms of 10 dairy farms from six different provinces in the Republic of Korea.
METHODS
Floor, wall, cheese board, room air, cheese rind and core were sampled from cheese ripening rooms of ten different dairy farms. The molds were enumerated using YM petrifilm, while isolation was done on yeast extract glucose chloramphenicol agar plates. Morphologically distinct isolates were identified using sequencing of internal transcribed spacer region.
RESULTS
The fungal counts in 8 out of 10 dairy farms were out of acceptable range, as per hazard analysis critical control point regulation. A total of 986 fungal isolates identified and assigned to the phyla Ascomycota (14 genera) and Basidiomycota (3 genera). Of these Penicillium, Aspergillus, and Cladosporium were the most diverse and predominant. The cheese ripening rooms was overrepresented in 9 farms by Penicillium (76%), while Aspergillusin a single farm. Among 39 species, the prominent members were Penicillium commune, P. oxalicum, P. echinulatum, and Aspergillus versicolor. Most of the mold species detected on surfaces were the same found in the indoor air of cheese ripening rooms.
CONCLUSION
The environment of cheese ripening rooms persuades a favourable niche for mold growth. The fungal diversity in the dairy farms were greatly influenced by several factors (exterior atmosphere, working personnel etc.,) and their proportion varied from one to another. Proper management of hygienic and production practices and air filtration system would be effective to eradicate contamination in cheese processing industries.
PubMed: 32054221
DOI: 10.5713/ajas.19.0553