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Frontiers in Microbiology 2022The utility of fungi as stabilizing and reducing agents in the biogenic synthesis of silver nanoparticles is striking due to the production of large quantities of...
The utility of fungi as stabilizing and reducing agents in the biogenic synthesis of silver nanoparticles is striking due to the production of large quantities of biomolecules of minute toxic residuals. During the current study, sunlight- and dark-assessed silver nanoparticles were synthesized from wasp nest fungus, , at different pHs. Synthesized silver nanoparticles (AgNPs) at 6 pH were found to be more prominent than at 7 and 8 pHs. AgNPs were within the 20- to 90-nm range and were polygonal and elongated in shape. FTIR spectra of light-mediated AgNPs showed diverse transmittance bands than the silver nanoparticles synthesized in the dark. The synthesized AgNPs were found with diverse antimicrobial activities against pathogenic MTCC bacterial strains, i.e., , , , , and fungus, . Aqueous filtrate and filtrate-mediated AgNPs combined with methanol solvent extract of yeast extract manitol broth (YEMB) had more inhibitory effects on all bacteria and . Furthermore, the combined effect of AgNPs and methanol solvent extract from YEMB culture filtrate was found more effective against , while AgNPs combined with methanol solvent of aqueous filtrate had inhibitory effects on and
PubMed: 35464920
DOI: 10.3389/fmicb.2022.841666 -
Frontiers in Microbiology 2022Cover crops are known to alleviate the adverse effects of continuous cropping by influencing plant health and changing host fungal-microbiome structures. However,...
Cover Plants-Mediated Suppression of Fusarium Wilt and Root-Knot Incidence of Cucumber is Associated With the Changes of Rhizosphere Fungal Microbiome Structure-Under Plastic Shed System of North China.
Cover crops are known to alleviate the adverse effects of continuous cropping by influencing plant health and changing host fungal-microbiome structures. However, insight into the shift of rhizomicrobiota composition and their effects on plant growth performance and resistance mechanism is still limited under plastic shed cultivation (PSC). Four leafy vegetable rotations namely spinach rotation (SR), non-heading Chinese cabbage rotation (NCCR), coriander rotation (CR), and leafy lettuce rotation (LLR) were used as cover crops in 7-years of continuous cucumber planted soil (CC). Their ecological impacts were studied for plant growth performance, replant diseases incidence rate, and rhizosphere fungal microbiome. Compared to CC, SR showed a highly suppressive effect on fusarium wilt, i.e., by 13.2% in the spring season, while NCCR decreased the root-knot nematode incidence rate by 8.9% in the autumn season. Such protective effects caused a significant increase of shoot and fruit biomass and thus sustained the fruit quality of cucumber. High-throughput sequencing revealed that the CR, SR, and NCCR treatments altered the fungal community composition by increasing the abundance of the beneficial fungal genera, decreasing pathogenic taxa, and fostering the saprotrophic and symbiotic functions. However, the relative abundance of most of the potentially pathogenic fungal genera increased in CC and LLR cropping. There were 8 potential pathogens and 10 beneficial or biocontrol fungi characterized. It was found that , , , , , and were the putative biocontrol microbes that positively affected plant growth and replanted diseases inhibition. The characterized , , , , and were the key pathogenic fungal agents found to be negatively associated with plant growth characters, suggesting that rhizomicrobiome may play an important role in the occurrence of disease incidence of cucumber plants. Considering the ecological potential of some cover plants, this study suggested that rotation with spinach, non-heading Chinese cabbage, or coriander can enhance rhizosphere immunity by triggering the development of plant-protective fungal microbiomes under plastic shed cucumber cultivation.
PubMed: 35444626
DOI: 10.3389/fmicb.2022.697815 -
Scientific Reports Apr 2022we optimized medium components for the production of ergosterol peroxide (EP) by Paecilomyces cicadae based on a mono-factor experiment, a uniform design, and a...
we optimized medium components for the production of ergosterol peroxide (EP) by Paecilomyces cicadae based on a mono-factor experiment, a uniform design, and a non-linear regression analysis. The maximum EP yield achieved was 256 μg/L, which was increased by 5 folds compared with that before the optimization. Structured Monod model, Andrews model, Contois model, and Aibe model were developed to describe the effects of viscosity inhibition, substrate, and production on biomass growth. The results showed that the Monod model could predict biomass growth, and the effects of viscosity and substrate on the EP concentration were significantly higher compared with the effect of production. The addition of water and glycerol could decrease the viscosity inhibition and glycerol inhibition, and further increase the EP yield. The newly developed structured model was demonstrated for batch growth of P. cicadae.
Topics: Cordyceps; Ergosterol; Fermentation; Glycerol; Models, Theoretical
PubMed: 35393454
DOI: 10.1038/s41598-022-09773-x -
Mycotoxin Research May 2022Fungi and mycotoxins in silage can have detrimental consequences for both cattle and human health. This pilot study identified, via the routinary direct plating method,...
Fungi and mycotoxins in silage can have detrimental consequences for both cattle and human health. This pilot study identified, via the routinary direct plating method, the dominant cultivable fungi in mouldy grass silages (GS) (n = 19) and maize silages (MS) (n = 28) from Austria. The profiles of regulated, modified, and emerging mycotoxins together with other fungal metabolites were analysed via LC-(ESI)MS/MS. Penicillium roqueforti, Saccharomyces spp., Geotrichum candidum, Aspergillus fumigatus and Monascus ruber were the most frequent fungal organisms identified. Other species including Mucor circinelloides, Fusarium spp. and Paecilomyces niveus were detected at lower frequencies. The presence of complex mixtures of toxic and potentially toxic compounds was evidenced by high levels and occurrences (≥ 50%) of Penicillium-produced compounds such as mycophenolic acid (MPA), roquefortines (ROCs), andrastins (ANDs) and marcfortine A. Mouldy silages contained toxins commonly produced by genus Fusarium (e.g. zearalenone (ZEN) and trichothecenes), Alternaria (like tenuazonic acid (TeA) and alternariol (AHO)) and Aspergillus (such as sterigmatocystin (STC)). Compared to those in GS, mouldy spots in MS presented significantly higher fungal counts and more diverse toxin profiles, in addition to superior levels of Fusarium spp., Penicillium spp. and total fungal metabolites. Generally, no correlation between mould counts and corresponding metabolites was detected, except for the counts of P. roqueforti, which were positively correlated with Penicillium spp. metabolites in mouldy MS. This study represents a first assessment of the fungal diversity in mouldy silage in Austria and highlights its potential role as a substantial contributor to contamination with complex mycotoxin mixtures in cattle diets.
Topics: Alternaria; Animals; Austria; Cattle; Food Contamination; Fusarium; Mycotoxins; Pilot Projects; Poaceae; Silage; Tandem Mass Spectrometry; Zea mays
PubMed: 35347677
DOI: 10.1007/s12550-022-00453-3 -
Food Science & Nutrition Mar 2022This study updates the mycobiota resident in groundnut seeds, their phenology during storage with the view to ascertain their occurrence, potential toxigenic species,...
This study updates the mycobiota resident in groundnut seeds, their phenology during storage with the view to ascertain their occurrence, potential toxigenic species, and pathologically important species in the stored samples. The moisture content of the seeds ranged from 5.7% to 6.5% within the stipulated safe moisture content of 8% for extension of shelf life. Culturing the seeds on mycological media (Sabouraud's Dextrose Agar SDA; Oxytetracycline Glucose Yeast Extract OGYE, Potato Dextrose Agar, PDA) caused a de novo growth of the quiescent spores at 28-30°C for 7-14 days. Fungal population counts on the three media ranged from 2.01 to 2.16 log CFU/g samples to a final 6-month count of 1.67-2.60 log CFU/g. Eighteen different fungal species belonging to ten genera were encountered on the media, namely , and . . (, and were the most frequently isolated, followed by , and and and , and . The species which were seed borne , and were isolated on both surface sterilized and non-surface sterilized seeds. The phenology of the encountered fungal species generally followed five patterns. The most frequently isolated , and predominated throughout the 6 months sampling period, while and appeared sporadically and disappeared. The early colonizers (, and ) could not be isolated after 2-3 months owing presumably to stronger antibiosis competition from the species. The most predominant species initially constituted 36%-48% of the total population but declined to 10%-36% in 6 months. Mycobiota encountered with mycotoxigenic potential and human health importance were , and . Other species of pathological importance to plants were and . The practical implications of these findings are discussed.
PubMed: 35311164
DOI: 10.1002/fsn3.2719 -
Communicative & Integrative Biology 2022Root-knot nematodes possess a major threat to agricultural production of various crops worldwide. The intensive use of chemical nematicides to control plant parasitic...
Root-knot nematodes possess a major threat to agricultural production of various crops worldwide. The intensive use of chemical nematicides to control plant parasitic nematodes has adverse effects on our environment and human health. Owing to the importance of developing new strategies, an experiment was conducted to reveal the influence of arbuscular mycorrhizal fungus, and nematophagous fungus, alone or in combination with various organic amendments such as superphosphate, green and organic manure to control the infection of root-knot, nematode in a vegetable crop . These two fungi along with soil amendments significantly improved plant growth and fruit yield and effectively controlled infection of . The dual inoculation of and reduced the number of galls and egg masses, thereby revealing the controlled proliferation of infection in roots. The beneficial effect of these fungi further increased on supplementation of soil with organic or green manures. Inoculation of with these two fungi showed a significant increase in egg parasitization; however, maximum effect was detected on dual inoculation. Amongst the soil amendments, the best response was obtained in case of green manure along with mycorrhizal fungus and . Present study revealed that nematophagous and AM fungi, in combination with green manure were effective in controlling , thus suggesting the use of such agents for biocontrol of plant parasitic nematodes in agriculture.
PubMed: 35273677
DOI: 10.1080/19420889.2021.2025195 -
Plant Disease Mar 2022Salix acmophylla Boss. (Brook willow), is native to Iran and mainly grows in natural riparian landscapes. It has excellent potential to use in erosion and...
Salix acmophylla Boss. (Brook willow), is native to Iran and mainly grows in natural riparian landscapes. It has excellent potential to use in erosion and phytoremediation projects. Since 2018, dieback has been observed on S. acmophylla at the Gilan-e Gharb forest (34°05'59.9"N, 46°00'52.6"E) in Kermanshah province, Iran. Affected trees showed wilting and yellowing of leaves, cankers, branch dieback, and decline (Fig. 1A, B). Small pieces (5 mm2) from the canker margins of 10 affected tree branches were surface sterilized with 75% ethanol for 30 s and 1% NaClO for 90 s. Subsequently, samples were rinsed three times with sterile H2O, plated on potato dextrose agar (PDA) supplemented with 100 mg/l streptomycin sulfate and 25 μg/mL chloramphenicole, and incubated at 25°C for 5 days. The same fungus was isolated from all samples. Pure cultures were obtained by monosporic isolation. A representative isolate, RU-PaMa-S1, was used for morphological and molecular characterization and deposited in the Fungal Reference Collection of the Ministry of Jihad-e Agriculture at the Iranian Research Institute of Plant Protection, Tehran, Iran. Radial growth of colonies on PDA and Czapek yeast extract agar (CYA) were 30 and 25 mm after seven days at 25 °C in the dark, respectively. Fungal colonies grew more rapidly on malt extract agar (MEA), and reaches a diameter of about 70 mm within 7 days at 25 °C in the dark. Color of colony on MEA, PDA, and CYA was light yellow to yellow-brown, which gets darker upon aging. In biochemical assay, our isolate grow and produced acid in culture on creatine sucrose agar medium. The conidiophore was irregularly branched out with one to seven phialides. The phialides were in whorls or solitary, flask shaped with cylindrical bases, and narrow apices. Conidia were one-celled, hyaline to yellow brown in mass, smooth, and ellipsoidal to cylindrical with truncate ends. Conidia were 3.0-9.6 (4.5) × 1.7-4.0 (2.6) µm (n = 50). Chlamydospores were present in two week old cultures. The morphology matched the description of Paecilomyces formosus (Sakag., May., Inoue and Tada) Houbraken and Samson (Samson et al., 2009). For an accurate identification, genomic DNA of RU-PaMa-S1 was extracted to amplify ITS regions, and β-tub gene with ITS1/ITS4 (White et al. 1990), and βt2a/βt2b (Glass and Donaldson 1995) primers, respectively. The sequences were deposited in GenBank (ITS: OL891502, β-tub OL944475). A BLAST search of GenBank showed that the ITS, and β-tub sequences of RU-PaMa-S1 were similar to those of Paecilomyces formosus. Baed on the multigene phylogeny and morphology, RU-PaMa-S1 isolate was identified as Paecilomyces formosus (Fig. 2). Molecular analyses based on sequencing of the ITS region, and parts of the β-tubulin and calmodulin genes, showed that P. formosus may be composed of three species, including P. maximus, P. lecythidis and P. formosus. However, the three species could be distinguished by only molecular data and not by microscopical examination (Samson et al. 2009). To fulfill Koch's postulates, 10 detached and 10 attached healthy branches from two 20-year-old S. acmophylla plants at the Gilan-e Gharb forest in Kermanshah province, Iran, were inoculated with 5-mm mycelial plugs of 5-day-old culture of RU-PaMa-S1 isolate (Fig. 1 C). Control branches were treated with agar plugs. The detached inoculated branches were stored in sterilized glass jar containing moist sponge and incubated at 25-30°C for 35 days until the appearance of the canker symptoms. After 35 days, inoculated branches were cut from the trees and transferred to the laboratory to check disease development and re-isolation of the pathogen. All inoculated points on detached and intact branches showed lesions similar to those observed on naturally infected trees, whereas controls were symptomless (Fig. 1 D, E). The same fungus was re-isolated from these lesions. P. formosus has been reported to infect a broad range of hosts, including Amygdalus scoparia, Malus domestica, Pistatia vera, and Querqus brantii (Sabbagh and Khosravi Moghaddam 2016; Sabernasab et al. 2019; Azizi et al. 2020). This is the first report of P. formosus on S. acmophylla in Iran and in the world. This finding provides crucial information on this high-risk disease to S. acmophylla and other forest trees and basis for identifying management strategies.
PubMed: 35259306
DOI: 10.1094/PDIS-12-21-2812-PDN -
American Journal of Ophthalmology Case... Jun 2022The aim of this report is to cover a novel presentation and subsequent management of () oculomycosis in a child, and to review the available literature on...
PURPOSE
The aim of this report is to cover a novel presentation and subsequent management of () oculomycosis in a child, and to review the available literature on endophthalmitis.
OBSERVATIONS
This report is of a four year old boy from Australia. There have been 13 previous reports of endophthalmitis, comprising 30 adult cases.
CONCLUSIONS
AND IMPORTANCE. is an emerging ocular infection, associated with use of this fungus as a biological control agent. This case highlights the importance of early consideration of intraocular fluid sampling in a case of vitritis non-responsive to steroid treatment. statementThe first reported case of atraumatic endophthalmitis, occurring in a child. All published endophthalmitis cases are reviewed.
PubMed: 35243147
DOI: 10.1016/j.ajoc.2022.101375 -
Archives of Pathology & Laboratory... Oct 2022There is no standardized process for utilization of periodic acid-Schiff during intraoperative frozen sections to identify fungal organisms.
CONTEXT.—
There is no standardized process for utilization of periodic acid-Schiff during intraoperative frozen sections to identify fungal organisms.
OBJECTIVE.—
To develop a rapid staining process for fresh tissue with periodic acid-Schiff during intraoperative consultation and develop an appropriate control block.
DESIGN.—
Muscle tissue was inoculated with 2 species of fungus (Aspergillus fumigatus and Paecilomyces spp) and grown at 3 different temperatures for 72 hours. Inoculated tissue was embedded in optimal cutting temperature compound, cut, and stained using a modified periodic acid-Schiff stain. The optimal control was determined for future use as the standard control. Multiple control slides were cut and stained, using successively shorter time intervals for each step. The staining process that provided accurate results in the shortest amount of time was deemed ultra-rapid periodic acid-Schiff. This method was validated by carryover studies and clinical specimens.
RESULTS.—
Paecilomyces spp incubated at 30°C for 72 hours was the most optimal positive control, with numerous yeast and hyphal forms. The fastest staining process involved 2 minutes of periodic acid and Schiff reagent and 10 dips of light green solution. Tap water was as effective as distilled water. Validation was successfully achieved. Clinical cases all stained identical to formalin-fixed, paraffin-embedded tissue stained with hematoxylin-eosin and periodic acid-Schiff.
CONCLUSIONS.—
Ultra-rapid periodic acid-Schiff provides fast and reliable identification of fungal organisms on fresh tissue. Development of a concurrent positive control allows for quality control and validation.
Topics: Coloring Agents; Eosine Yellowish-(YS); Formaldehyde; Frozen Sections; Fungi; Hematoxylin; Humans; Methyl Green; Periodic Acid; Staining and Labeling; Water
PubMed: 35104313
DOI: 10.5858/arpa.2021-0273-OA -
Current Biology : CB Mar 2022The horizontal transfer of large gene clusters by mobile elements is a key driver of prokaryotic adaptation in response to environmental stresses. Eukaryotic microbes...
The horizontal transfer of large gene clusters by mobile elements is a key driver of prokaryotic adaptation in response to environmental stresses. Eukaryotic microbes face similar stresses; however, a parallel role for mobile elements has not been established. A stress faced by many microorganisms is toxic metal ions in their environment. In fungi, identified mechanisms for protection against metals generally rely on genes that are dispersed within an organism's genome. Here, we discover a large (∼85 kb) region that confers tolerance to five metal/metalloid ions (arsenate, cadmium, copper, lead, and zinc) in the genomes of some, but not all, strains of a fungus, Paecilomyces variotii. We name this region HEPHAESTUS (Hφ) and present evidence that it is mobile within the P. variotii genome with features characteristic of a transposable element. HEPHAESTUS contains the greatest complement of host-beneficial genes carried by a transposable element in eukaryotes, suggesting that eukaryotic transposable elements might play a role analogous to bacteria in the horizontal transfer of large regions of host-beneficial DNA. Genes within HEPHAESTUS responsible for individual metal tolerances include those encoding a P-type ATPase transporter-PcaA-required for cadmium and lead tolerance, a transporter-ZrcA-providing tolerance to zinc, and a multicopper oxidase-McoA-conferring tolerance to copper. In addition, a subregion of Hφ confers tolerance to arsenate. The genome sequences of other fungi in the Eurotiales contain further examples of HEPHAESTUS, suggesting that it is responsible for independently assembling tolerance to a diverse array of ions, including chromium, mercury, and sodium.
Topics: Byssochlamys; Cadmium; Copper; DNA Transposable Elements; Zinc
PubMed: 35063120
DOI: 10.1016/j.cub.2021.12.048