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1.
J Sci Food Agric ; 91(3): 492-7, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21218483

RESUMO

BACKGROUND: Increasing evidence of fungicide-resistant toxinogenic and pathogenic fungal species is obvious. Looking for new possibilities of antifungal treatment or sources of antifungal substances is a major problem. Some medicinal plants exert strong antifungal properties and could be conveniently used as a promising alternative source for presently problematic antifungal treatment in many areas with respect to their natural origin. Methanol extracts of 46 medicinal plants from the Eurasian area were used in a screening assay for antifungal activity in this study. The growth inhibitory effect was tested against six significant pathogenic and toxinogenic fungal species: Fusarium oxysporum, F. verticillioides, Penicillium expansum, P. brevicompactum, Aspergillus flavus and A. fumigatus. RESULTS: For 14 plant species, the possibility of using them as natural fungicides was indicated. The extract from Grindelia camporum showed significant activity against all target fungal species. The most sensitive target fungus was the toxinogenic and human pathogenic species A. fumigatus. CONCLUSION: This study has identified 14 extracts of medicinal plants with a potential use as an antifungal treatment in various areas. One of them showed promising efficiency against all selected significant pathogenic and toxinogenic fungal species.


Assuntos
Antifúngicos/farmacologia , Fungos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Plantas Medicinais , Ásia , Europa (Continente)
2.
Plants (Basel) ; 10(10)2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34685990

RESUMO

The antifungal and insecticidal effect of the essential oil from Ocimum sanctum L. was evaluated using a model set of harmful organisms hazardous for health and the economy. Toxigenic and plant pathogenic filamentous fungi, including causal agents of human infections, were chosen as exemplary fungal groups-Fusarium verticillioides, Penicillium expansum and Aspergillus flavus. Spodoptera littoralis (African cotton leafworm), Culex quinquefasciatus (Southern house mosquito), the lymphatic filariasis vector and potential Zika virus vector, and the common housefly, Musca domestica were chosen as model insects. Major and minor active substances were detected and quantified using GC/MS analysis. Environmental safety was verified using the non-target useful organism Eisenia fetida. Significant antifungal and insecticidal activity, as well as environmental safety, were confirmed. The essential oil showed the highest efficacy against A. flavus according to MIC50/90, and against S. littoralis larvae according to LD50/90. The monoterpenoid alcohol linalool, t-methyl cinnamate, and estragole as phenylpropanoids were detected as effective major components (85.4%). The essential oil from Ocimum sanctum L. was evaluated as universal and significantly efficient, providing a high potential for use in environmentally safe botanical pesticides.

3.
J Nat Prod ; 73(6): 1027-32, 2010 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-20509707

RESUMO

Pseudallescheria boydii sensu lato is an emerging fungal pathogen causing fatal infections in both immunocompromised and immunocompetent hosts. In this work, two P. boydii isolates (human and animal origin) have been identified as being producers of cyclic peptides. Five putative nonribosomal peptides with a unique structure, which have been named pseudacyclins, were characterized by nuclear magnetic resonance spectroscopy and mass spectrometry. The most abundant representative of the pseudacyclins was quantified also on fungal spores. The presence of these peptides on inhaled fungal spores creates the possibility for exploitation of pseudacyclins as early indicators of fungal infections caused by Pseudallescheria species.


Assuntos
Peptídeos Cíclicos/isolamento & purificação , Pseudallescheria/química , Sequência de Aminoácidos , Animais , Humanos , Camundongos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Peptídeos Cíclicos/química , Pseudallescheria/patogenicidade
4.
Int J Spine Surg ; 12(4): 441-452, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30276104

RESUMO

BACKGROUND: This trial reports the 2-year and immediate postremoval clinical outcomes of a novel posterior apical short-segment (PASS) correction technique allowing for correction and stabilization of adolescent idiopathic scoliosis (AIS) with limited fusion. METHODS: Twenty-one consecutive female AIS patients were treated at 4 institutions with this novel technique. Arthrodesis was limited to the short apical curve after correction with translational and derotational forces applied to upper and lower instrumented levels. Instrumentation spanned fused and unfused segments with motion and flexibility of unfused segments maintained. The long concave rods were removed at maturity. Radiographic data collected included preoperative and postoperative data for up to 2 years as well as after long rod removal. RESULTS: All 21 patients are beyond 2 years postsurgery. Average age at surgery was 14.2 years (11-17 years). A mean of 10.5 ± 1 levels per patient were stabilized and 5.0 ± 0.5 levels (48%) were fused. Cobb angle improved from 56.1° ± 8.0° to 20.8° ± 7.8° (62.2% improvement) at 1 year and 20.9° ± 8.4°, (62.0% improvement) at 2 years postsurgery. In levels instrumented but not fused, motion was 26° ± 6° preoperatively compared to 10° ± 4° at 1 year postsurgery, demonstrating 38% maintenance of mobility in nonfused segments. There was no report of implant-related complications. CONCLUSIONS: PASS correction technique corrected the deformity profile in AIS patients with a lower implant density while sparing 52% of the instrumented levels from fusion through the 2-year follow-up.

5.
J Mass Spectrom ; 39(8): 949-60, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15329847

RESUMO

Profiling of cyclic tetradepsipeptides beauverolides was tested as a chemotaxonomic tool for fungal strain identification/discrimination. Two new tetradepsipeptides, beauverolides Q and R, were characterized by tandem mass spectrometry. Specific elimination of 113 atomic mass units from both protonated and sodiated molecules of beauverolides is ubiquitous for all 12 most dominant congeners evaluated in this profiling study. Reconstruction of the total ion chromatogram, according to this neutral fragment release, was used for data filtering and selectivity enhancement. Selective ring opening and fragment ion formation of beauverolide I are discussed in detail utilizing high-level theoretical modeling of the fragmentation pathways.


Assuntos
Depsipeptídeos , Fungos/metabolismo , Peptídeos Cíclicos/metabolismo , Ribossomos/metabolismo , Biomarcadores/análise , Cromatografia Líquida de Alta Pressão , Fungos/classificação , Peptídeos/química , Peptídeos Cíclicos/análise , Peptídeos Cíclicos/química , Prótons , Especificidade da Espécie , Espectrometria de Massas por Ionização por Electrospray
6.
Artigo em Inglês | MEDLINE | ID: mdl-12748394

RESUMO

High-performance liquid chromatography and tandem mass spectrometry (HPLC/MS/MS) was used for the detection of cyclic hexadepsipeptides roseotoxins produced by Trichothecium roseum. Roseotoxins were found in both submerged standard cultivation on CzapekDox medium and in vivo cultivation extract obtained from an apple. Roseotoxin chromatographic profiles from these two experiments were compared. Product-ion collision-induced dissociation (CID) spectra obtained on an ion trap (electrospray ionisation, ESI) were used for the identification of natural roseotoxins A, B, C and of minor destruxins A and B. The dissociation behavior of roseotoxins is discussed in terms of a fragmentation scheme proposed for describing the dissociation pathways of cyclic peptides. This scheme involves opening of the cyclopeptide ring via formation of oxazolone derivatives and fragmentation of the resulting linear species, which have a free N-terminus and an oxazolone ring at the C-terminus. Some aspects of this fragmentation scheme are underlined by modeling the dissociation channels of roseotoxin A using quantum chemical calculations. The structures of roseotoxin A and destruxin B were verified by nuclear magnetic resonance (NMR) spectroscopy. Structures of three new minor natural roseotoxins [Val(4)]RosA, [MeLxx(4)]RosA and [MeLxx(4)]RosB were deduced by ion cyclotron resonance Fourier transform mass spectrometry (ICR-FT-MS) and ion trap tandem mass spectrometry by examining the pre-separated roseotoxin fraction.


Assuntos
Depsipeptídeos , Fungos Mitospóricos/química , Peptídeos Cíclicos/biossíntese , Peptídeos Cíclicos/química , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Peptídeos Cíclicos/análise , Peptídeos Cíclicos/síntese química
7.
Chemosphere ; 112: 443-8, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25048938

RESUMO

Health affecting, loss-inducing or otherwise harmful fungal pathogens (molds) pose a serious challenge in many areas of human activities. On the contrary, frequent use of synthetic fungicides is undesirable in some cases and may be equally problematic. Moreover, the ever more increasing fungal resistance against commercial synthetic fungicides justifies development of rising efforts to seek new effective, while environmentally friendly alternatives. Botanical fungicides based on Essential oils (EOs) undoubtedly provide such an alternative. The study explores the efficacy of 20 EOs against Alternaria alternata, Stachybotrys chartarum, Cladosporium cladosporioides and Aspergillus niger, related to abundance of majority active substances. Minimum inhibitory concentration (MIC100 and MIC50) was evaluated. GC-MS analysis revealed high abundance of highly effective phenolic compounds whose different molecular structures correlates with differences in EOs efficacy. The efficacy of some EOs, observed in our study, can be similar to the levels of some synthetic fungicides used in medicine and agriculture e.g. sometimes problematic azole-based formulations. Thanks to the EOs environmental safety and natural origin, they offer the potential to become an alternative where the use of synthetic fungicides is impossible for various reasons.


Assuntos
Microbiologia do Ar , Antifúngicos/química , Antifúngicos/farmacologia , Hipersensibilidade/microbiologia , Fungos Mitospóricos/efeitos dos fármacos , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Cromatografia Gasosa-Espectrometria de Massas , Testes de Sensibilidade Microbiana
8.
Chemosphere ; 93(6): 1051-6, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23800587

RESUMO

In terms of food safety, species of the Fusarium, Aspergillus and Penicillium genera are considered the most significant because they produce the great majority of known mycotoxins. Developing resistance against commonly used fungicides have become a critical problem in area such as agriculture, the storage and production of food and even in human medicines. The need for research and development of new alternative antifungal treatment based on natural antifungal substances is obvious. Here, the antifungal efficacy of 21 phenolic components of essential oils and plant substances were tested against these filamentous fungi with respect to their different molecular structures. Minimum inhibitory concentration values MIC50 and MIC100 were successfully estimated for 15 substances by means of probit analysis. Thymol and carvacrol were evaluated as the most effective. The MIC50 values for thymol ranged from 30 to 52 µg mL(-1). The MIC100 values for thymol ranged from 76 to 255 µg mL(-1), respectively. For carvacrol, the MIC50 values ranged from 37 to 76 µg mL(-1), and the MIC100 ranged from 131 to 262 µg mL(-1). The results also revealed differences in the efficacy of phenols depending on molecular structures and different inter-species sensitivity.


Assuntos
Antifúngicos/toxicidade , Fungos/efeitos dos fármacos , Fenóis/toxicidade , Aspergillus/efeitos dos fármacos , Fusarium/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Óleos Voláteis/toxicidade , Penicillium/efeitos dos fármacos
9.
Mycopathologia ; 162(1): 65-8, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16830194

RESUMO

Apples were exposed to various concentrations of roseotoxins - metabolites of Trichothecium roseum and kinetic fluorescence imaging was used to detect the area influenced by the phytotoxin. Contrast was quantified within these images between the areas exposed to roseotoxins and the untreated areas. It was proved that roseotoxin B is able to penetrate apple peel and produce chlorotic lesions. Activity of roseotoxin B is similar as the activity of destruxins, host specific phytotoxins of Alternaria brassicae parasitic on canola.


Assuntos
Depsipeptídeos/metabolismo , Malus , Fungos Mitospóricos/metabolismo , Doenças das Plantas/microbiologia , Depsipeptídeos/toxicidade , Fluorometria
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