48 research outputs found
Isolation and characterization of carbendazim-degrading bacteria from agricultural soil samples
The use of chemical pesticides in agriculture generates many ecological and human toxicological problems. One of the most frequently used fungicides is carbendazim, however, in spite of its importance, there are only a few reports dealing with its microbial degradation in the environment. It has high acute ecotoxicological effect, as well as a suspected endocrine disruptor potential, so its residues in food and feed are dangerous. Until now, single isolates of Pseudomonas, Rhodococcus and Ralstonia have been found to be able to degrade carbendazim. Among fungi, one isolate of Alternaria alternata and Phanaerochete crysosporium were described as good carbendazim degraders. Bacterial degradation pathways have been partially explored: the first step is the hydrolysis of the carbamate group, followed by a ring-fission in 2-aminobenzimidazole resulting 1,2-diaminobenzene. This compound is further metabolized via the beta-ketoadipic acid pathway. As part of our studies on pesticide biodegradation, new carbendazim-metabolizing bacteria were isolated from Hungarian agricultural soil samples. These degrader bacteria were isolated from soil samples by microbiological enrichment methods. The molecular analysis revealed that the best isolates belong to the Variovorax paradoxus species. The isolate 10/1 was able to use carbendazim as sole carbon and nitrogen source. The pH optimum and temperature optimum for growth were found to be pH 6.3 and 30 °C, respectively. This isolate seems to be an efficient tool for the bioremediation of carbendazim polluted agricultural soils
Qualitative and quantitative characterization of a coal power plant waste by TG/DSC/MS, XRF and XRD
SO2 removal from coal-fired power plant flue gases can be done by dry, semi-dry or wet desulphurization processes, using limestone or lime-containing products as sorbents. In a Brazilian coal power plant, there is a dry desulphurization unit to capture SO2 with hydrated lime from the combustion gases. A part of the flying ashes produced is mixed with the bottom coal ashes and the spent sulphated product generated after SO2 capture. This residual solid blend is then buried in a non-productive area, from which coal was already extracted and is studied in this work. According to the authors’ experience in the development and characterization of adsorbents for low temperature dry desulphurization processes and in thermogravimetric analysis, this paper shows and discusses a method which was developed to characterize qualitatively and quantitatively the chemical and mineral composition of this waste by using thermogravimetry coupled with mass spectrometry, X-ray fluorescence and X-ray diffraction, to preview new potential industrial applications for this waste.We are thankful to the University of Cantabria for the financial support under the Project: 51.VP61.64005, to the Brazilian Research Council, under the project CNPq no. 407005/2013-7, and to the Brazilian Education Council CAPES
Recurrent Scedosporium apiospermum mycetoma successfully treated by surgical excision and terbinafine treatment: a case report and review of the literature
Background:
Scedosporium apiospermum
is an emerging opportunistic filamentous fungus, which is notorious for its
high levels of antifungal
‑resistance. It is able to cause localized cutaneous or subcutaneous infections in both immu‑
nocompromised and immunocompetent persons, pulmonary infections in patients with predisposing pulmonary
diseases and invasive mycoses in immunocompromised patients. Subcutaneous infections caused by this fungus
frequently show chronic mycetomatous manifestation.
Case report:
We report the case of a 70
‑year
‑old immunocompromised man, who developed a fungal mycetoma‑
tous infection on his right leg. There was no history of trauma; the aetiological agent was identified by microscopic
examination and ITS sequencing. This is the second reported case of
S. apiospermum
subcutaneous infections in
Hungary, which was successfully treated by surgical excision and terbinafine treatment. After 7
months, the patient
remained asymptomatic. Considering the antifungal susceptibility and increasing incidence of the fungus,
Sce
-
dosporium
related subcutaneous infections reported in the past quarter of century in European countries were also
reviewed.
Conclusions:
Corticosteroid treatment represents a serious risk factor of
S. apiospermum
infections, especially if the
patient get in touch with manure
‑enriched or polluted soil or water. Such infections have emerged several times in
European countries in the past decades. The presented data suggest that besides the commonly applied voricona‑
zole, terbinafine may be an alternative for the therapy of mycetomatous
Scedosporium
infections
Finding needles in haystacks: Linking scientific names, reference specimens and molecular data for Fungi
DNA phylogenetic comparisons have shown that morphology-based species recognition
often underestimates fungal diversity. Therefore, the need for accurate DNA sequence
data, tied to both correct taxonomic names and clearly annotated specimen data, has
never been greater. Furthermore, the growing number of molecular ecology and microbiome
projects using high-throughput sequencing require fast and effective methods for
en masse species assignments. In this article, we focus on selecting and re-annotating a
set of marker reference sequences that represent each currently accepted order of Fungi.
The particular focus is on sequences from the internal transcribed spacer region in the
nuclear ribosomal cistron, derived from type specimens and/or ex-type cultures. Reannotated
and verified sequences were deposited in a curated public database at the
National Center for Biotechnology Information (NCBI), namely the RefSeq Targeted Loci
(RTL) database, and will be visible during routine sequence similarity searches with
NR_prefixed accession numbers. A set of standards and protocols is proposed to improve
the data quality of new sequences, and we suggest how type and other reference
sequences can be used to improve identification of Fungi.B.R. and C.L.S. acknowledge support from the Intramural Research
Program of the National Institutes of Health, National Library of
MedicinePeer Reviewe
Thermogravimetric analysis of selected group (II) carbonateminerals - Implication for the geosequestration of greenhouse gases
The precursors of carbonate minerals have the potential to react with greenhouse gases to form many common carbonate minerals. The carbonate bearing minerals, magnesite, calcite, strontianite and witherite, were synthesised and analysed using a combination of thermogravimetry and evolved gas mass spectrometry. The DTG curves show that as both the mass and the size of the metal cationic radii increase, the inherent thermal stability of the carbonate also increases dramatically. It is proposed that this inherent effect is a size stabilisation relationship between that of the carbonate and the metal cation. As the cationic radius increases in size, the radius approaches and in the case of Sr2+ and Ba2+ exceeds that of the overall size of the carbonate anion. The thermal stability of these minerals has implications for the geosequestration of greenhouse gases. The carbonates with the larger cations show significantly greater stability
A Commercial Extract of Cyanotis arachnoidea Roots as a Source of Unusual Ecdysteroid Derivatives with Insect Hormone Receptor Binding Activity
Genome expansion and lineage-specific genetic innovations in the forest pathogenic fungi Armillaria
Black Aspergilli and fumonisin contamination in onions purchased in Hungary
Black mould rot caused by black Aspergilli is an important post-harvest disease of onion worldwide. Usually Aspergillus niger is cited as the causative agent based on morphological criteria. In this study, the mycobiota and fumonisin contamination of mouldy onion bulbs purchased in Hungary were examined. All except one of the examined mouldy samples were found to be contaminated with black Aspergilli, which could be isolated both from the outer dry and the inner fleshy scales of onion bulbs. Species assignment of the isolates was carried out using sequence analysis of part of the calmodulin gene. Sequence data revealed that all 35 black Aspergilli isolated from onions belong to the Aspergillus awamori species. The range of fumonisin isomers present in the onion samples was also examined using reversed-phase high-performance liquid chromatography/electrospray ionization-ion trap mass spectrometry. Two of the examined onion samples were found to be contaminated with fumonisins at a rate of about 0.3 mg kg−1. This is the first report on fumonisin contamination of onion bulbs. The fumonisin isomers observed include fumonisins B2–4, 3-epi-FB4, iso-FB Tartalomjegyzék 1(FB Tartalomjegyzék 6) and an iso-FB2,3 form. The range of fumonisin isomers detected in the onion bulbs indicates that probably A. awamori is responsible both for mould rot and fumonisin contamination of onions in Hungary