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Microbiology Spectrum Jun 2024During construction work (2017-2019), an increase in infections was noted among pediatric patients, the majority of whom were receiving amphotericin B prophylaxis....
UNLABELLED
During construction work (2017-2019), an increase in infections was noted among pediatric patients, the majority of whom were receiving amphotericin B prophylaxis. Microsatellite genotyping was used to characterize the outbreak. A total of 153 . isolates of clinical and environmental origin were included. Clinical isolates included 140 from 119 patients. Eight patients were outbreak-related patients, whereas 111 were outbreak-unrelated patients from Danish hospitals (1994-2023). We further included four control strains. Nine isolates were from subsequent air sampling in the outbreak ward (2022-2023). Typing followed Rudramurthy et al.(S. M. Rudramurthy, H. A. de Valk, A. Chakrabarti, J. Meis, and C. H. W. Klaassen, PLoS One 6:e16086, 2011, https://doi.org/10.1371/journal.pone.0016086). Minimum spanning tree (MST) and discriminant analysis of principal components (DAPC) were used for cluster analysis. DAPC analysis placed all 153 isolates in five clusters. Microsatellite marker pattern was clearly distinct for one cluster compared to the others. The same cluster was observed in an MST. This cluster included all outbreak isolates, air-sample isolates, and additional patient isolates from the outbreak hospital, previously undisclosed as outbreak related. The highest air prevalence of was found in two technical risers of the outbreak ward, which were then sealed. Follow-up air samples were negative for . Microsatellite typing defined the outbreak as nosocomial and facilitated the identification of an in-hospital source. Six months of follow-up air sampling was without . Outbreak-related/non-related isolates were easily distinguished with DAPC and MST, as the outbreak clone's distinct marker pattern was delineated in both statistical analyses. Thus, it could be a variant of , with a niche ability to thrive in the outbreak-hospital environment.
IMPORTANCE
can cause severe infections and hospital outbreaks in immunocompromised individuals. Although lack of isogeneity does not preclude an outbreak, our study underlines the value of microsatellite genotyping in the setting of potential outbreaks. Microsatellite genotyping documented an isogenic hospital outbreak with an internal source. This provided the "smoking gun" that prompted the rapid allocation of resources for thorough environmental sampling, the results of which guided immediate and relevant cleaning and source control measures. Consequently, we advise that vulnerable patients should be protected from exposure and that genotyping be included early in potential outbreak investigations. Inspection and sampling are recommended at any site where airborne spores might disperse from. This includes rarely accessed areas where air communication to the hospital ward cannot be disregarded.
PubMed: 38888358
DOI: 10.1128/spectrum.00273-24 -
FEMS Microbiology Ecology Jun 2024Fungi are increasingly recognized to play diverse roles within honey bee hives, acting as pathogens, mutualists, and commensals. Pollen products, essential for hive...
Fungi are increasingly recognized to play diverse roles within honey bee hives, acting as pathogens, mutualists, and commensals. Pollen products, essential for hive nutrition, host significant fungal communities with potential protective and nutritional benefits. In this study, we profile the fungal communities and antifungal properties of three pollen products from healthy and stressed hives: fresh pollen collected by forager bees from local plants; stored pollen packed into the comb inside the hive; and bee bread, which is stored pollen following anaerobic fermentation used for bee and larval nutrition. Using amplicon sequencing, we found significant differences in fungal community composition, with hive health and sample type accounting for 8.8% and 19.3% of variation in beta diversity, respectively. Pollen and bee bread extracts had species-specific antimicrobial activity and inhibited the fungal hive pathogens Ascosphaera apis, Aspergillus flavus, and Aspergillus fumigatus, and the bacterial hive pathogen Paenibacillus larvae. Activity was positively correlated with phenolic and antioxidant content and was diminished in stressed hives. The plant source of pollen determined by amplicon sequencing differed in stressed hives, suggesting altered foraging behaviour. These findings illustrate the complex interplay between honey bees, fungal communities, and hive products, which should be considered in hive management and conservation.
Topics: Bees; Animals; Pollen; Fungi; Stress, Physiological; Paenibacillus larvae; Mycobiome; Ascomycota; Anti-Infective Agents
PubMed: 38886123
DOI: 10.1093/femsec/fiae091 -
Bioresources and Bioprocessing Jun 2024Nanoparticles (NPs) formulation in biopolymers is an attractive process for the researcher to decrease the disadvantages of NPs application alone. Bimetallic NPs are a...
Nanoparticles (NPs) formulation in biopolymers is an attractive process for the researcher to decrease the disadvantages of NPs application alone. Bimetallic NPs are a promising formula of two NPs that usually act as synergetic phenomena. Zinc oxide and gold NPs (ZnO@AuNPs) biosynthesis as a bimetallic was prepared via the eco-friendly manner currently. Carboxymethylcellulose (CMC) was employed for the formulation of ZnO@AuNPs as a nanocomposite via a green method. Physicochemical and topographical characterization was assigned to ZnO@AuNPs and nanocomposite features. The nanostructure of bimetallic NPs and nanocomposite were affirmed with sizes around 15 and 25 nm, respectively. Indeed, the DLS measurements affirmed the more reasonable size and stability of the prepared samples as 27 and 93 nm for bimetallic NPs and nanocomposite, respectively. The inhibitory potential of nanocomposite was more than ZnO@AuNPs against Staphylococcus aureus, Escherichia coli, Salmonella typhi, Enterococcus faecalis, Mucor albicans, Aspergillus flavus, and Mucor circinelloid. ZnO@AuNPs and nanocomposite exhibited antioxidant activity via DPPH with IC of 71.38 and 32.4 µg/mL, correspondingly. Excellent anti-diabetic potential of nanocomposite with IC of 7.4 µg/mL, and ZnO@AuNPs with IC of 9.7 µg/mL was reported compared with the standard acarbose with the IC of 50.93 µg/mL for amylase inhibition (%). Photocatalytic degradation of RR195 and RB dyes was performed by ZnO@AuNPs and nanocomposite, where maximum degradation was 85.7 ± 1.53 and 88.7 ± 0.58%, respectively using ZnO@AuNPs, 90.3 ± 0.28 and 91.8 ± 0.27%, respectively using nanocomposite at 100 min.
PubMed: 38884830
DOI: 10.1186/s40643-024-00759-3 -
Heliyon Jun 2024Surface-active softening agents, such as Fatliquors, have a significant impact on the leather industry as they enhance the physicochemical properties of leather. This...
Surface-active softening agents, such as Fatliquors, have a significant impact on the leather industry as they enhance the physicochemical properties of leather. This study focuses on analyzing the synthesis, properties, characterization, and sulfonation of seed oil to determine its potential as a fatliquoring agent for leather. An investigation was conducted to verify the alteration of oil through the analysis of its properties before and after the sulfonation process. A scientific analysis was carried on the oil using GC-FID, revealing the presence of various unsaturated fatty acids such as linoleic, linolenic, oleic, palmitic, and arachidic acids. This demonstrates the sulfonating capability of this sky fruit seed oil. A fatliquor was created by sulfonating the oil, and the sulfonation was verified through Fourier Transform Infrared Spectroscopy (FTIR) and H Nuclear Magnetic Resonance (NMR) spectra. The prominent peak observed at 1209 cm-1 in the FTIR spectra indicated the stretching of S=O in both sulfate and sulfonate groups. The newly formed protons (H-C-S or H-C-O) showed signals between δ 4.09 and 4.29 ppm in the H NMR spectra, confirming the sulfonation of the fatliquor that was prepared. Moreover, the change in the melting point of sulfonated Mahogany oil from 40.8 °C to 48.1 °C suggests increased saturation levels. The fatliquor's emulsion stability was found to be at a satisfactory level. After conducting tests on the treated leather, the physical strength and morphological structure was analyzed using Field Emission Scanning Electron Microscopy (FE-SEM), the fatliquor improved the lubrication and strengthened the fibrous network structure of the leather, composed of thin and tight collagen fibers. The BOD5/COD ratio of the effluent from the experimental trial was determined to be 0.52, suggesting that the fatliquor developed is a biodegradable product. Finally, the antifungal capabilities of the fatliquor-treated leather were tested against four different fungus species: and the treated leather sample shown favorable antifungal activity.
PubMed: 38882293
DOI: 10.1016/j.heliyon.2024.e31598 -
Microbial Pathogenesis Jun 2024Nano-biotechnology is quickly developing as an important field of modern research, generating the most promising applications in medicine and agriculture. Biosynthesis...
Nano-biotechnology is quickly developing as an important field of modern research, generating the most promising applications in medicine and agriculture. Biosynthesis of silver nanoparticles using biogenic or green approach provide ecofriendly, clean and effective way out for the synthesis of nanoparticles. The main aim of the study was to synthesize silver nanoparticles (AgNPs) from Aspergillus niger, Aspergillus flavus and Pencillium chrysogenum using a green approach and to test the antifungal activity of these synthesized AgNPs against a variety of pathogenic fungi. The characterization of samples was done by using UV-visible spectroscopy, SEM (scanning electron microscopy), FTIR (Fourier transmission infrared spectroscopy), and XRD (X-ray diffractometry). The investigation confirmed the creation of AgNPs by the fungi Aspergillus niger, Aspergillus flavus and Pencillium chrysogenum, as evidenced by prominent plasmon absorbance bands at 420 and 450 nm.The biosynthesized AgNPs were 80-100 nm in size, asymmetrical in shape and became spherical to sub-spherical when aggregated. Agar well diffusion method was performed to evaluate the antifungal activity of AgNPs against various plant pathogenic fungi. An efficient and strong antifungal activity was shown by these biosynthesized nanoparticles against serious plant pathogenic fungi, viz. Aspergillus terreus, Fusarium oxysporum, Penicillium citrinum, Rhizopus stolonifer and Mucor mucedo. The biosynthesized AgNPs at various concentrations caused significant zone of inhibition in the test fungal pathogens. Silver nanoparticles (AgNPs) biosynthesized from Aspergillus niger at highest concentrations showed maximum zone of inhibition against Penicillium citrinum (19.33 ± 0.57 mm) followed by Rhizopus stolonifer (17.66 ± 0.57), Aspergillus terreus (16.33 ± 1.54 mm), Fusarium oxysporum (14.00 ± 1.00 mm) and Mucor mucedo (13.33 ± 1.15 mm) respectively. Therefore, the findings clearly indicate that silver nanoparticles could play a significant role in managing diverse plant diseases caused by fungi.
PubMed: 38879139
DOI: 10.1016/j.micpath.2024.106742 -
Food Chemistry Jun 2024This study investigated the application of a hybrid nanocomposite of tin oxide nanorods (SnO NRs) and graphene oxide (GO) for the chemoresistive detection of some...
This study investigated the application of a hybrid nanocomposite of tin oxide nanorods (SnO NRs) and graphene oxide (GO) for the chemoresistive detection of some volatile compounds (hexanal, benzaldehyde, octanal, 1-octanol, and ethyl acetate vapours) emitted by Aspergillus flavus under simulated conditions. The synthesised materials were characterised using various analytical techniques, including high-resolution transmission electron microscopy (HR-TEM), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) analysis, and Fourier transform infrared spectroscopy (FTIR). Three sensors were fabricated: individual nanomaterials (i.e., SnO and GO) and composites (SnO-GO). The results showed that SnO NRs had limited sensitivity as a sensor, while GO-based sensors responded to various analyte vapours. However, the incorporation of SnO NRs into GO layers resulted in synergistic effects and improved sensor performance. The sensors' sensitivity, selectivity, recovery, and response times were quantitatively determined from the sensors' response curves. The nanocomposite sensor demonstrated superior sensitivity and selectivity for analyte vapours with acceptable response and recovery times. In addition, the sensor was insensitive to humidity and showed robust performance up to 62% RH, although sensor drift occurred at 70% RH. This study highlights the promising potential of using SnO NRs-GO composite-based sensor for sensitive and selective detection of analyte vapours, which has significant implications for food safety and environmental monitoring applications.
PubMed: 38878549
DOI: 10.1016/j.foodchem.2024.140068 -
BMC Microbiology Jun 2024Fungi can spoil the majority of baked products. Spoilage of cake during storage is commonly associated with fungi. Therefore, this study aimed to assess the quality of...
Fungi can spoil the majority of baked products. Spoilage of cake during storage is commonly associated with fungi. Therefore, this study aimed to assess the quality of different types of cakes sold in the market. The most predominant fungal genera in the tested cake samples (14 samples) were Aspergillus spp., and Penicillium spp. On Potato Dextrose Agar (PDA), the medium fungal total count was 43.3 colonies /g. Aspergillus was the most dominant genus and was isolated from six samples of cake. Aspergillus was represented by 3 species namely, A. flavus, A. niger, and A. nidulans, represented by 13.32, 19.99, and 3.33 colonies /g respectively. On Malt Extract Agar (MEA) Medium, the fungal total count was 123.24 colonies / g. Aspergillus was the most dominant isolated genus from 11 samples of cake and was represented by 5 species, namely, A. flavus, A. niger, A. ochraceous, A. terreus, and A. versicolor (26. 65, 63.29, 3.33, 6.66, and 3.33 colonies / g , respectively). Twenty-four isolates (88.88 %) of the total tested twenty-seven filamentous fungi showed positive results for amylase production. Ten isolates (37.03%) of the total tested filamentous fungi showed positive results for lipase production, and finally eleven isolates (40.74 %) of the total fungal isolates showed positive results for protease production. Aflatoxins B, B G G and ochratoxin A were not detected in fourteen collected samples of cake. In this study, clove oil was the best choice overpeppermint oil and olive oil for preventing mold development when natural agents were compared. It might be due to the presence of a varietyof bioactive chemical compounds in clove oil, whose major bioactive component is eugenol, which acts as an antifungal reagent. Therefore, freshly baked cake should be consumed within afew days to avoid individuals experiencing foodborne illnesses.
Topics: Fungi; Food Microbiology; Mycotoxins; Aspergillus; Penicillium; Food Contamination; Aflatoxins; Lipase; Amylases
PubMed: 38877423
DOI: 10.1186/s12866-024-03345-x -
BMC Chemistry Jun 2024Newly synthesized ligand 2-(2- acetamidophenyl)-2-oxo-N-(pyridin-2-ylmethyl)acetamide and its copper(II) complex were characterized by elemental analyses, FT-IR,...
Experimental and theoretical quantum chemical studies of 2-(2-acetamidophenyl)-2-oxo-N-(pyridin-2-ylmethyl)acetamide and its copper(II) complex: molecular docking simulation of the designed coordinated ligand with insulin-like growth factor-1 receptor (IGF-1R).
Newly synthesized ligand 2-(2- acetamidophenyl)-2-oxo-N-(pyridin-2-ylmethyl)acetamide and its copper(II) complex were characterized by elemental analyses, FT-IR, UV-Vis., ESR, H-NMR, and thermal analysis along with the theoretical quantum chemical studies. Combined experimental and theoretical DFT (density functional theory) studies showed the ligand to be a tridentate ligand with three coordinate bonds. The complex was suggested to be in a distorted octahedral structure with d ground state. The activation energy, ΔE; entropy ΔS; enthalpy ΔH and order of reaction has been derived from differential thermogravimetric (DTA) curve, using Horowitz-Metzeger method. The nujol mull electronic spectrum of the ligand and Cu(II) complex have been recorded and the difference of the excited and ground state densities has also been theoretically calculated and plotted to investigate the movement of electrons on excitation. The Cu(II) complex was evaluated for its antibacterial activity against two bacterial species, namely Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). Antifungal screening was performed against two species (Condida albicans and Aspergillus flavus). The complex under investigation was found to possess notable biological activity. Molecular docking investigation predicted different types of non-covalent interactions of the synthesized ligand towards Insulin-like growth factor 1 receptor (ID: 5FXR).
PubMed: 38872213
DOI: 10.1186/s13065-024-01217-z -
Environmental Health Insights 2024Aflatoxins (AFs) are secondary metabolites mainly produced by and and their contamination of red peppers can cause hepatocellular carcinoma, growth retardation in...
Aflatoxins (AFs) are secondary metabolites mainly produced by and and their contamination of red peppers can cause hepatocellular carcinoma, growth retardation in children, immune suppression, and death. In addition, their presence in the red peppers can affect international trade and cause significant economic burdens. Thus, the objective of this study was to assess the level of AFs contamination in packed powder (from supermarkets) and raw red pepper samples commercially available in the towns of Fiche and Mukaturi. Furthermore, this study aimed to determine the potential health and cancer risks associated with the consumption of red pepper contaminated with AFs. Red pepper samples (raw and packed powder) were collected randomly from the Fiche and Mukaturi open markets. Then AFs in the samples were extracted using methanol: water (80:20, v/v). These extract samples were then cleaned up using an immunoaffinity column (IAC) and determined with a high-performance liquid chromatography-fluorescence detector (HPLC-FLD). The finding showed that the amount of AFB, AFB, and AFG in raw red pepper was found to be 3.19 ± 0.01, 0.19 ± 0.001, and 4.07 ± 0.01 μg kg, respectively. The raw red pepper samples had a total of 7.66 ± 0.01 μg kg of AFs. On the other hand, the amount of AFB, AFB, and AFG in Afiya-packed red pepper was found to be 7.04 ± 0.03, 2.15 ± 0.06, and 0.50 ± 0.01 μg kg, while Mudayi packed red pepper contained 31.60 ± 0.22, 24.40 ± 0.17, 3.37 ± 0.02 and 2.48 ± 0.004 μg kg of aflatoxins, respectively. Afiya and Mudayi packed powder peppers had a total AFs content of 10.4 ± 0.07 and 61.90 ± 0.28 μg kg, respectively. The total AFs concentrations in packed pepper powder samples were higher than maximum toleratable limits (MTLs) set by the European Commission Regulation (EU) 2023/915 (5.00 μg kg for AFB and 10 μg kg for total AFs). AFB (31.60 ± 0.22 μg kg) had the highest level of contamination, followed by AFB (24.40 ± 0.17 μg kg) in packed pepper powder. In the adult population, the estimated daily intake (EDI) of AFB, AFB, AFG, and AFG ranged from 0.80 to 7.90, 0.04 to 6.10, 0.02 to 1.02, and 0.05 to 0.62 g kg body weight (bw) per day, respectively. However, the Margins of Exposure (MOE) values and combined Margin of Exposure (MoET) for these chemicals were significantly lower than the safe margin (<10 000). Therefore, this study highlights the potential health risks associated with consuming AFs-contaminated red peppers and the need for stricter regulations and monitoring to ensure food safety.
PubMed: 38863690
DOI: 10.1177/11786302241257746 -
Journal of Microbiology and... May 2024Fungi generate different metabolites some of which are intrinsically bioactive and could therefore serve as templates for drug development. In the current study, six...
Fungi generate different metabolites some of which are intrinsically bioactive and could therefore serve as templates for drug development. In the current study, six endophytic fungi namely and were isolated and identified from the medicinal plant, These endophytic fungi were identified through intra transcribed sequence (ITS) gene sequencing. The bioactive potentials of fungal extracts were investigated using several bioassays such as antibacterial activity by well-diffusion, MIC, MBC, anti-biofilm, antioxidant, and haemolysis. The strain PAO1 was used to determine the antibiofilm activity. The ethyl acetate extract of Aspergillus flavus showed strong to moderate efficacy against , and and exhibited significant antibiofilm activity with IC at 4.02 and 3.63 mg/ml while exhibited maximum antioxidant activity of 50.8%. Based on, HPLC, LC-MS and NMR experiments kojic acid (1) and carbamic acid (methylene-4, 1-phenylene) bis-dimethyl ester (2) were identified from Kojic acid exhibited DPPH free radical scavenging activity with an IC value of 99.3 μg/ml and moderate activity against ovarian teratocarcinoma (CH1), colon carcinoma (SW480), and non-small cell lung cancer (A549) cell lines. These findings suggest that endophytic fungi are able produce promising bioactive compounds which deserve further investigation.
PubMed: 38858094
DOI: 10.4014/jmb.2403.03036