1.The use of phosphorus nanoparticles synthesized by rhizospheric fungus Aspergillius fumigatus as a nanofertilizer for flax plant
Rabaa Yaseen ; Basma Hamdy Amin
Malaysian Journal of Microbiology 2021;17(3):244-253
Aims:
This study examined the mycosynthesis of phosphorus nanoparticles (PNPs) and its application as a fertilizer for flax plant.
Methodology and results:
A total of thirty eight fungal isolates were isolated and screened for their abilities to
synthesize PNPs. The fungal isolate was determined and identified as Aspergillus fumigatus (NCBI GenBank accession
No. MN610566-MN610567). The biosynthesized nanoparticles were characterized by particle size analyzer, UV-visible
spectrophotometer, transmission electron microscope (TEM), energy-dispersive X-ray spectroscopy (EDX) and fourier
transform infrared spectroscopy (FT-IR). They were found to have an average diameter of 45.1 nm, regular round
shape, EDX confirms the 54.63 atom % of phosphorous. The cytotoxicity of produced nanoparticles was performed to
determine the safe dose that will be applied in agricultural experiment and was found to be 12.5 μg/mL. Pot experiment
was performed to determine the fertilizing impact of mycosynthesized PNPs on flax plant and to equate their influence
with granular single super phosphate. Results revealed that growth parameters, phosphorus content and microbial
activities in the rhizosphere of flax plants were highly significantly (p ≤ 0.05) affected by foliar application of PNPs in
presence of half dose of super phosphate. The TEM-micrographs of stained ultrastructural leaves showed that the PNPs
treated leaves in the presence of half dose of super phosphate had normal cell structure similar to control, while the cell
structure of leaves treated with PNPs but did not receive super phosphate were adversely affected.
Conclusion, significance and impact of study
This study clearly indicated that the application of low cost
biosynthesised PNPs could save about 50% of recommended dose of phosphorus fertilizer. This study also
demonstrates that it is not preferred to use PNPs as a fertilizer alone without adding super phosphate. Hence, this
investigation suggests that further studies should be established to detect the safety of this nanofertilizers.
Nanoparticles--chemistry
;
Aspergillus fumigatus
2.Isolation and Identification of Aspergillus Section Fumigati Strains from Arable Soil in Korea.
Seung Beom HONG ; Dae Ho KIM ; In Cheol PARK ; Robert A SAMSON ; Hyeon Dong SHIN
Mycobiology 2010;38(1):1-6
63 strains of Aspergillus section Fumigati were isolated from 17 samples of arable soil in a central province of Korea. Based on the results of genotypic and phenotypic analyses, they were identified as Aspergillus fumigatus, A. lentulus, Neosartorya coreana, N. fennelliae, N. fischeri, N. glabra, N. hiratsukae, N. laciniosa, N. pseudofischeri, N. quadricincta, N. spinosa and N. udagawae. Among these, N. fennelliae, N. hiratsukae, N. quadricincta, and N. udagawae had not been previously recorded in Korea. The diversity of Aspergillus section Fumigati species from arable soil in Korea is also addressed.
Aspergillus
;
Aspergillus fumigatus
;
Korea
;
Neosartorya
;
Soil
3.Effect of Temperature and Relative Humidity on Growth of Aspergillus and Penicillium spp. and Biocontrol Activity of Pseudomonas protegens AS15 against Aflatoxigenic Aspergillus flavus in Stored Rice Grains.
Mycobiology 2018;46(3):287-295
In this study, we evaluated the effect of different temperatures (10, 20, 30, and 40 °C) and relative humidities (RHs; 12, 44, 76, and 98%) on populations of predominant grain fungi (Aspergillus candidus, Aspergillus flavus, Aspergillus fumigatus, Penicillium fellutanum, and Penicillium islandicum) and the biocontrol activity of Pseudomonas protegens AS15 against aflatoxigenic A. flavus KCCM 60330 in stored rice. Populations of all the tested fungi in inoculated rice grains were significantly enhanced by both increased temperature and RH. Multiple linear regression analysis revealed that one unit increase of temperature resulted in greater effects than that of RH on fungal populations. When rice grains were treated with P. protegens AS15 prior to inoculation with A. flavus KCCM 60330, fungal populations and aflatoxin production in the inoculated grains were significantly reduced compared with the grains untreated with strain AS15 regardless of temperature and RH (except 12% RH for fungal population). In addition, bacterial populations in grains were significantly enhanced with increasing temperature and RH, regardless of bacterial treatment. Higher bacterial populations were detected in biocontrol strain-treated grains than in untreated control grains. To our knowledge, this is the first report showing consistent biocontrol activity of P. protegens against A. flavus population and aflatoxin production in stored rice grains under various environmental conditions of temperature and RH.
Aflatoxins
;
Aspergillus flavus*
;
Aspergillus fumigatus
;
Aspergillus*
;
Fungi
;
Humidity*
;
Linear Models
;
Penicillium*
;
Pseudomonas*
4.Biocontrol Activity of Volatile-Producing Bacillus megaterium and Pseudomonas protegens Against Aspergillus and Penicillium spp. Predominant in Stored Rice Grains: Study II.
Mycobiology 2018;46(1):52-63
In our previous studies, Bacillus megaterium KU143, Microbacterium testaceum KU313, and Pseudomonas protegens AS15 have been shown to be antagonistic to Aspergillus flavus in stored rice grains. In this study, the biocontrol activities of these strains were evaluated against Aspergillus candidus, Aspergillus fumigatus, Penicillium fellutanum, and Penicillium islandicum, which are predominant in stored rice grains. In vitro and in vivo antifungal activities of the bacterial strains were evaluated against the fungi on media and rice grains, respectively. The antifungal activities of the volatiles produced by the strains against fungal development and population were also tested using I-plates. In in vitro tests, the strains produced secondary metabolites capable of reducing conidial germination, germ-tube elongation, and mycelial growth of all the tested fungi. In in vivo tests, the strains significantly inhibited the fungal growth in rice grains. Additionally, in I-plate tests, strains KU143 and AS15 produced volatiles that significantly inhibited not only mycelial growth, sporulation, and conidial germination of the fungi on media but also fungal populations on rice grains. GC-MS analysis of the volatiles by strains KU143 and AS15 identified 12 and 17 compounds, respectively. Among these, the antifungal compound, 5-methyl-2-phenyl-1H-indole, was produced by strain KU143 and the antimicrobial compounds, 2-butyl 1-octanal, dimethyl disulfide, 2-isopropyl-5-methyl-1-heptanol, and 4-trifluoroacetoxyhexadecane, were produced by strain AS15. These results suggest that the tested strains producing extracellular metabolites and/or volatiles may have a broad spectrum of antifungal activities against the grain fungi. In particular, B. megaterium KU143 and P. protegens AS15 may be potential biocontrol agents against Aspergillus and Penicillium spp. during rice grain storage.
Aspergillus flavus
;
Aspergillus fumigatus
;
Aspergillus*
;
Bacillus megaterium*
;
Bacillus*
;
Fungi
;
Germination
;
In Vitro Techniques
;
Penicillium*
;
Pseudomonas*
6.In Vitro Antifungal Activity and Mode of Action of 2',4'-Dihydroxychalcone against Aspergillus fumigatus.
Young Ho SEO ; Sung Su KIM ; Kwang Soo SHIN
Mycobiology 2015;43(2):150-156
2',4'-Dihydroxychalcone (2',4'-DHC) was identified from a heat shock protein 90 (Hsp90)-targeting library as a compound with Hsp90 inhibitory and antifungal effects. In the presence of 2',4'-DHC (8 microg/mL), radial growth of Aspergillus fumigatus was inhibited 20% compared to the control, and green pigmentation was completely blocked. The expression of the conidiation-associated genes abaA, brlA, and wetA was significantly decreased (approximately 3- to 5-fold) by treatment with 2',4'-DHC. The expression of calcineurin signaling components, cnaA and crzA, was also significantly reduced. The inhibitory effects of 2',4'-DHC on metabolic activity and mycelial growth were significantly enhanced by combination treatment with itraconazole and caspofungin. Docking studies indicated that 2',4'-DHC bind to the ATPase domain of Hsp90. These results suggest that 2',4'-DHC act as an Hsp90-calcinurin pathway inhibitor.
Adenosine Triphosphatases
;
Aspergillus fumigatus*
;
Calcineurin
;
Heat-Shock Proteins
;
Itraconazole
;
Pigmentation
7.Regulation of Development in Aspergillus nidulans and Aspergillus fumigatus.
Mycobiology 2010;38(4):229-237
Members of the genus Aspergillus are the most common fungi and all reproduce asexually by forming long chains of conidiospores (or conidia). The impact of various Aspergillus species on humans ranges from beneficial to harmful. For example, several species including Aspergillus oryzae and Aspergillus niger are used in industry for enzyme production and food processing. In contrast, Aspergillus flavus produce the most potent naturally present carcinogen aflatoxins, which contaminate various plant- and animal-based foods. Importantly, the opportunistic human pathogen Aspergillus fumigatus has become the most prevalent airborne fungal pathogen in developed countries, causing invasive aspergillosis in immunocompromised patients with a high mortality rate. A. fumigatus produces a massive number of small hydrophobic conidia as the primary means of dispersal, survival, genome-protection, and infecting hosts. Large-scale genome-wide expression studies can now be conducted due to completion of A. fumigatus genome sequencing. However, genomics becomes more powerful and informative when combined with genetics. We have been investigating the mechanisms underlying the regulation of asexual development (conidiation) and gliotoxin biosynthesis in A. fumigatus, primarily focusing on a characterization of key developmental regulators identified in the model fungus Aspergillus nidulans. In this review, I will summarize our current understanding of how conidiation in two aspergilli is regulated.
Aflatoxins
;
Aspergillosis
;
Aspergillus
;
Aspergillus flavus
;
Aspergillus fumigatus
;
Aspergillus nidulans
;
Aspergillus niger
;
Aspergillus oryzae
;
Developed Countries
;
Food Handling
;
Fungi
;
Genome
;
Genomics
;
Gliotoxin
;
Humans
;
Immunocompromised Host
;
Spores, Fungal
;
Transcription Factors
8.A Case of Corneal Ulcer Caused by Combined Infection of Stenotrophomonas Maltophilia and Aspergillus Fumigatus.
Journal of the Korean Ophthalmological Society 2000;41(5):1242-1246
Stenotrophomonas maltophilia keratitis is rare and none of it has been reported to be combined with Aspergillus keratitis.I have experienced a corneal ulcer caused by combined infection of S.maltophilia and A. fumigatus.S. maltophilia was grown on culture and a brownish pigmented anterior chamber mass containing filamentous fungi was attached to corneal ulcer area endothelium without the usual filamentous fungal keratitis findings such as feathery edge, satellite lesions, endothelial plaques, etc. A spergillusfumigatus was grown on culture of abscess which developed along the superior incision for removal of anterior chamber mass.
Abscess
;
Anterior Chamber
;
Aspergillus fumigatus*
;
Aspergillus*
;
Corneal Ulcer*
;
Endothelium
;
Fungi
;
Keratitis
;
Stenotrophomonas maltophilia*
;
Stenotrophomonas*
9.Secretion of Interleukin-8 from Human Keratocyte Stimulated by Aspergillus fumigatus and Effect of Amphotericin B and Dexamethasone on The Secretion.
Dong Jun LEE ; Gi Su AHN ; Ju Heon RHO ; Young Ho HAHN
Journal of the Korean Ophthalmological Society 2001;42(8):1220-1226
PURPOSE: To measure the secretion of IL-8 from cultured human keratocytes after inoculation of conidia of A. fumigatus, and to compare the change of secretion of IL-8 following application of amphotericin B and dexamethasone. METHODS: Human corneal keraoctytes were cultured independently in vitro. The specimens were divided into 4 groups : Group I with only pure culture as control, Group II with conidia of A. fumigatus, Group III with conidia of A. fumigatus and amphotericin B, and Group IV with conidia of A. fumigatus and dexamethasone. The supernatants were aspirated from each group at different time intervals, and then were assayed for IL-8. RESULTS: Group II showed increased secretion of IL-8, at all selected time intervals except 12-h, in comparison with other three groups. Group III secreted IL-8 significantly less than the other groups(p<0.01). Group IV secreted IL-8 less than Group I and II at all selected time points(p<0.01), but more than Group III at the other time points except for 72-h(p<0.01). CONCLUSIONS: The secretion of IL-8 increased in the early stage of fungal keratitis but decreased in case of the administration of amphotericin B or dexamethasone. Amphotericin B was more potent than dexamethasone in decreasing the secretion of IL-8.
Amphotericin B*
;
Aspergillus fumigatus*
;
Aspergillus*
;
Dexamethasone*
;
Humans*
;
Interleukin-8*
;
Keratitis
;
Spores, Fungal
10.Sputum Inflammatory Mediators Are Increased in Aspergillus fumigatus Culture-Positive Asthmatics.
Michael A GHEBRE ; Dhananjay DESAI ; Amisha SINGAPURI ; Joanne WOODS ; Laura RAPLEY ; Suzanne COHEN ; Athula HERATH ; Andrew J WARDLAW ; Catherine H PASHLEY ; Richard MAY ; Chris E BRIGHTLING
Allergy, Asthma & Immunology Research 2017;9(2):177-181
Aspergillus fumigatus sensitization and culture in asthma are associated with disease severity and lung function impairment, but their relationship with airway inflammation is poorly understood. We investigated the profile of 24 sputum inflammatory mediators in A. fumigatus culture-positive or-negative moderate-to-severe asthmatics. Fifty-two subjects were recruited from a single center. A. fumigatus was cultured from 19 asthmatics. Asthma control, symptom score, lung function, and sputum cell count were not significantly different between the asthmatics with and without a positive A. fumigatus culture. All of the sputum mediators were numerically increased in subjects with a positive versus negative sputum A. fumigatus culture. Sputum TNF-R2 was significantly elevated (P=0.03) and the mediator that best distinguished A. fumigatus culture-positive from culture-negative subjects (receiver-operator characteristic area under the curve 0.66 [95% CI: 0.51 to 0.82, P=0.045]). A. fumigates-positive culture in moderate-to-severe asthma is associated with increased inflammatory sputum mediators.
Aspergillus fumigatus*
;
Aspergillus*
;
Asthma
;
Cell Count
;
Inflammation
;
Lung
;
Receptors, Tumor Necrosis Factor, Type II
;
Sputum*