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1.
Nat Prod Res ; : 1-6, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38579277

RESUMO

Fusarium graminearum causes destructive ear rot diseases in maize and wheat. New antifungals are essential to combat this pathogen, and aerial parts of Justicia species (Acanthaceae) are a potential source. We investigated the antifungal activity of extracts from stems and leaves of five Justicia species native to Northwest Argentina. The aerial parts were subjected to sequential extractions with dichloromethane, ethyl acetate, and methanol. The resulting extracts were tested by the disc diffusion method against F. graminearum strains. Only the leaf and stem extracts from J. xylosteoides displayed inhibitory effects, with the dichloromethane leaf extract as the most active. The compounds involved were identified as the lignans hinokinin, savinin, and isohibalactone. Both the dichloromethane extract and hinokinin synergised with tebuconazole, and inhibited deoxynivalenol biosynthesis. The identified compounds warrant further research as additives to azole fungicides for F. graminearum control.

2.
Nat Prod Res ; 37(23): 4058-4062, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36622895

RESUMO

Essential oils from aerial parts of six aromatic plants were analysed by GC-MS. The major compounds identified were γ-terpinene (11.5%), cuminaldehyde (26.6%) and γ-terpinen-7-al (40.6%) in Cuminum cyminum, trans-anethol (95.2%) in Pimpinella anisum, α-pinene (11.6%), limonene (21.0%), ß-caryophyllene (22.3%) and α-humulene (16.7%) in Lippia integrifolia, limonene (40.8%) and artemisia ketone (19.3%) in Lippia junelliana, trans-ß-ocimene (15.6%), 4-ethyl-4-methyl-1-hexene (24.5%), trans-tagetone (20.5%) and verbenone (27.2%) in Tagetes minuta, 1,8-cineole (17.9%),elixene (10.3%) and spathulenol (13.8%) in Aloysia gratissima. Oils with strong insecticidal activity on Carpophilus dimidiatus and Oryzaephilus mercator were from P. anisum (LC50 = 4 µl/L; LC100 = 10 µl/L) and T. minuta (LC50=10.19-12.57 µl/L; LC100=20 µl/L). Scents of C. cyminum and L. junelliana were strong insecticides on O. mercator (LC50=7.02-7.17 µl/L; LC100=10.00-20.00 µl/L). The insecticidal activity was associated to the whole content of C10 molecules and oxygenated constituents. The P. anisum oil is promising as protective agent of nut products.


Assuntos
Besouros , Inseticidas , Óleos Voláteis , Animais , Óleos Voláteis/farmacologia , Limoneno , Inseticidas/farmacologia , Argentina
3.
Bol. latinoam. Caribe plantas med. aromát ; 22(1): 115-129, ene. 2023. tab, graf, ilus
Artigo em Inglês | LILACS | ID: biblio-1555348

RESUMO

The stem bark of Geoffroea decorticans (Gill.ex Hook. etArn.) Burk. was used medicinally to cure several skin affections; however, phytochemical and biological antecedents were not found. Analyses of purified methanolic extract from G. decorticans bark (PFGB), realized by silylation derivatization for GC/MS, C18-CC and HPLC followed by two-dimensional TLC and UV-Vis spectroscopy, allowed to characterize nine phenolic compounds, among these, two methoxy flavonoids. Antibacterial assays of PFGB showed the highest activity (MICs = 125 µg/mL) against Staphylococcus aureus (25923) and Enterococcus faecalis (29212) ATCC strains. Moreover, PFGB showed the highest intracellular antioxidant activity at low concentration (5 µg/mL), evaluated by using the fluorescent DA-H2DCF probe on lymphocyte culture; cytotoxic effects on lymphocytes activated or not by LPS were not observed, through Trypan Blue Exclusion and MTT colorimetric assays. The results obtained from the ethnomedicinal approach of this work contribute to the scientific validation of the vulnerary medicinal use of G. decorticans.


La corteza de Geoffroea decorticans (Gill.ex Hook. EtArn.) Burk. se utiliza con fines medicinales para curar diferentes afecciones de la piel; sin embargo, no encontramos antecedentes fitoquímicos y biológicos que validen las propiedades medicinales atribuidas. Analizamos el extracto metanólico purificado de corteza de G. decorticans (PFGB), por CG-EM de la muestra derivatizada por sililación, C18-CC y HPLC seguido de CCF bidimensional, y espectroscopia UV-Vis; estos métodos nos permitieron caracterizar nueve compuestos fenólicos, entre estos, dos metoxi-flavonoides. Los ensayos antibacterianos de PFGB mostraron mayor actividad (CIMs = 125 µg/mL) contra las cepas ATCC de Staphylococcus aureus (25923) y Enterococcus faecalis (29212). Además, PFGB evidenció la mayor actividad antioxidante intracelular a baja concentración(5 µg/mL), evaluada en cultivo de linfocitos, mediante el uso de sonda fluorescente DA-H2DCF; no se observaron efectos citotóxicos sobre linfocitos activados o no por LPS, a través de ensayos colorimétricos con MTT y test de exclusión con azul Tripán. Los resultados obtenidos del abordaje etnomedicinal de este trabajo, contribuyen con la validación científica del uso medicinal vulnerario de G. decorticans.


Assuntos
Extratos Vegetais/química , Fabaceae/química , Antibacterianos/química , Fenóis/análise , Espectrofotometria/métodos , Staphylococcus aureus/efeitos dos fármacos , Extratos Vegetais/farmacologia , Testes de Sensibilidade Microbiana , Cromatografia Líquida/métodos , Enterococcus faecalis/efeitos dos fármacos , Casca de Planta , Metanol , Medicina Tradicional , Antibacterianos/farmacologia
4.
Nat Prod Res ; 34(18): 2656-2659, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30663355

RESUMO

Twenty four extracts from Bignoniaceae plants of northwest Argentina were tested for antifungal activity against Aspergillus species responsible of the grape black rot. Stems and leaves of Amphilophium cynanchoides, Macfadyena cynanchoides, Tecoma stans and Jacaranda mimosifolia were separately extracted with solvents of increasing polarity to obtain the dichloromethane (fCH2Cl2), ethyl acetate (fEtOAc) and methanol extracts (fMeOH). The fCH2Cl2 from stem of M. cynanchoides had the lowest IC50 (1.0-1.2 mg/mL) and MID values (0.6-1.2 mg) and the highest ID values (5.0-6.8 mm) on A. niger and A. carbonarius. The main contributors of the antifungal activity of fCH2Cl2 were identified as lapachol (MIC = 0.25-1.00 mg/ml) and 1-hydroxy-4-methylanthraquinone (MIC = 0.0625-0.125 mg/mL). These compounds synergized the antifungal activity of sodium metabisulfite and showed an additive effect in mixtures with propiconazol. They might be used as additives of commercial antifungals to protect grapes against A. niger and A. carbonarius.


Assuntos
Antifúngicos/isolamento & purificação , Aspergillus niger/efeitos dos fármacos , Bignoniaceae/química , Antifúngicos/farmacologia , Aspergillus/efeitos dos fármacos , Bignoniaceae/microbiologia , Ocratoxinas , Doenças das Plantas/microbiologia , Folhas de Planta/química , Caules de Planta/química , Vitis/microbiologia
5.
Nat Prod Res ; 34(22): 3299-3302, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30663391

RESUMO

Extracts from aerial parts of Prosopis ruscifolia, Bidens pilosa, Cercidium praecox and Phoradendron liga were assayed against toxigenic Aspergillus species. They were obtained by sequential extraction of the aerial parts with hexane (fHex), dichloromethane (fDCM), ethyl acetate (fEtOAc) and methanol (fMeOH). The fMeOH from P. ruscifolia showed the highest antifungal spectrum (MIC = 750-1500 µg mL-1; MID = 50-200 µg; DI = 1.7-3.0 mm). Indolizidine alkaloids (juliflorine and juliprosine) and tryptamine were identified with strong (MIC = 188 µg mL-1) and moderate antifungal activities (MIC = 750 µg mL-1), respectively, towards A. parasiticus and A. flavus. The fMeOH, the indolizidine alkaloids and tryptamine synergized the fungitoxic effect of potassium sorbate and propiconazole. They completely suppressed the biosynthesis of aflatoxins at concentrations of 47, 94 and 375 µg mL-1, respectively. Our results indicate that fMeOH and its identified alkaloids are promisory additives of commercial antifungals and are antiaflatoxigenic agents at concentrations below of those required for complete suppression of fungal growth.


Assuntos
Antifúngicos/farmacologia , Aspergillus/efeitos dos fármacos , Extratos Vegetais/farmacologia , Plantas/química , Aflatoxinas/metabolismo , Alcaloides/química , Alcaloides/farmacologia , Antifúngicos/química , Argentina , Aspergillus/metabolismo , Bidens/química , Avaliação Pré-Clínica de Medicamentos , Microbiologia de Alimentos , Fungicidas Industriais/química , Fungicidas Industriais/farmacologia , Indolizinas/farmacologia , Metanol/química , Testes de Sensibilidade Microbiana , Componentes Aéreos da Planta/química , Componentes Aéreos da Planta/metabolismo , Extratos Vegetais/química , Prosopis/química , Triptaminas/farmacologia
6.
Nat Prod Res ; 34(10): 1442-1445, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-30456990

RESUMO

Essential oils from aerial parts of Senecio nutans, Senecio viridis, Tagetes terniflora and Aloysia gratissima were analysed by GC-MS and their antifungal activities were assayed on toxigenic Fusarium and Aspergillus species. Sabinene (27.6 ± 0.1%), α-phellandrene (15.7 ± 0.3%), o-cymene (9.6 ± 0.2%) and ß-pinene (6.1 ± 0.2%) in S. nutans, 9,10-dehydrofukinone (92.7 ± 0.2%) in S. viridis, ß-thujone (36.1 ± 0.1%), α-thujone (32.2 ± 0.2%), 1,8-cineol (10.7 ± 0.1%) and sabinene (6.2 ± 0.2%) in A. gratissima, and cis-tagetone (33.6 ± 0.2%), cis-ß-ocimene (17.1 ± 0.2%), trans-tagetone (17.0 ± 0.1%), cis-ocimenone (8.0 ± 0.2%) and trans-ocimenone (8.2 ± 0.1%) in T. terniflora. The oils showed moderate antifungal activity (1.2 mg/mL > MIC >0.6 mg/mL) on the Fusarium species and a weak effect on Aspergillus species. The antifungal activity was associated on F. verticillioides to the high content of cis-tagetone, trans-tagetone, cis-ß-ocimene, cis-ocimenone, trans-ocimenone and on F. graminearum due to the total content of oxygenated sesquiterpenes and 9,10- dehydrofukinone. The oil of S. viridis synergized the effect of fungicides and food preservatives on F. verticillioides.[Formula: see text].


Assuntos
Antifúngicos/química , Antifúngicos/farmacologia , Aspergillus/efeitos dos fármacos , Fusarium/efeitos dos fármacos , Óleos Voláteis/química , Monoterpenos Bicíclicos/análise , Monoterpenos Cicloexânicos/análise , Conservação de Alimentos , Testes de Sensibilidade Microbiana , Óleos Voláteis/farmacologia , Componentes Aéreos da Planta/química , Senécio/química , Tagetes/química , Verbenaceae/química
7.
Int J Food Microbiol ; 305: 108242, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31176953

RESUMO

Fusarium meridionale and F. boothii cause Gibberella Ear Rot (GER) in maize. This study determined the effects of temperature (5-35 °C) and water activity (0.90-0.995 aw) on the growth, and deoxynivalenol (DON) and nivalenol (NIV) production of F. meridionale and F. boothii strains in maize grains. Fusarium graminearum sensu stricto strains from wheat were also tested. The three Fusarium species grew best at 0.995 aw and 25 °C. Growth was absent or marginal at 0.90 aw regardless of temperature. F. meridionale and F. boothii were sensitive to 30 °C and more affected by water stress than F. graminearum sensu stricto. The highest DON levels were at 0.995-0.97 aw and 30 °C and at 0.97 aw and 20 °C for F. graminearum sensu stricto, and at 0.995-0.97 aw and 20 °C for F. boothii. Fusarium meridionale reached maximum NIV accumulation at 0.995 aw and 20 °C. This produced DON at negligible levels compared to the other two Fusarium species. Growth of F. meridionale and F. boothii was well adapted to the usual autumn high humidity and mild temperatures associated with GER in northwest Argentina. Control strategies during grain development should be taken into account to reduce the risk of the presence of DON and NIV in the harvested grains.


Assuntos
Fusarium/metabolismo , Doenças das Plantas/microbiologia , Tricotecenos/metabolismo , Água/análise , Zea mays/microbiologia , Argentina , Fusarium/classificação , Fusarium/crescimento & desenvolvimento , Fusarium/isolamento & purificação , Umidade , Estações do Ano , Temperatura , Tricotecenos/análise , Triticum/química , Triticum/microbiologia , Água/metabolismo , Zea mays/química
8.
Nat Prod Res ; 31(12): 1464-1467, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27879146

RESUMO

The composition of essential oils from leaves of Kazakhstan medicinal plants was analysed by GC-MS. The major compounds identified were 1,8-cineole (34.2%), myrcene (19.1%) and α-pinene (9.4%) in Ajania fruticulosa; 1,8-cineole (21.0%), ß-thujone (11.0%), camphor (8.5%), borneol (7.3%) and α-thujone (6.5%), in Achillea nobilis; camphor (47.3%), 1,8-cineole (23.9%), camphene (9.8%) and ß-thujone (6.0%) in Artemisia terrae-albae; 1,8-cineole(55.8%) and ß-pinene (6.2%) in Hyssopus ambiguus; α-thuyene(46.3%) and δ-cadinene(6.3%) in Juniperus sibirica; sabinene (64%) in Juniperus sabina; and α-pinene (51.5%), ß-phellandrene (11.2%) and δ-cadinene (6.3%) in Pinus sibirica. The essential oils did not show antifungal effect (MIC > 1.20 mg/mL) on Aspergillus carbonarius and Aspergillus niger, while the oils from A. nobilis, A. terrae-albae, H. ambiguus and J. sabina exhibited moderate and moderate to weak antimicrobial activities on Fusarium verticillioides (MIC = 0.60 mg/mL) and Fusarium graminearum (MIC = 0.60-1.20 mg/mL), respectively. A principal component analysis associated the antifungal activity (r2 > 0.80, p = 0.05) with the presence of borneol, camphor, camphene, 1,8-cineole,α- and ß-thujone, and of the oxygenated monoterpenes.


Assuntos
Antifúngicos/farmacologia , Óleos Voláteis/farmacologia , Plantas Medicinais/química , Cazaquistão , Folhas de Planta/química , Análise de Componente Principal
9.
Nat Prod Res ; 30(17): 1950-5, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26404704

RESUMO

Essential oils from aerial parts of Acantholippia deserticola, Artemisia proceriformis, Achillea micrantha and Libanotis buchtormensis were analysed by GC-MS. The major compounds identified were ß-thujone (66.5 ± 0.2%), and trans-sabinyl acetate (12.1 ± 0.2%) in A. deserticola; α-thujone (66.9 ± 0.4%) in A. proceriformis; 1,8-cineole (26.9 ± 0.5%), and camphor (17.7 ± 0.3%) in A. micrantha and cis-ß-ocimene (23.3 ± 0.3%), and trans-ß-ocimene (18.4 ± 0.2%) in L. buchtormensis. The oils showed a weak antimicrobial effect (MIC100 > 1.5 mg/ml) on most phytopathogens tested. A moderate antimicrobial activity (MIC100 between 0.5 and 1.5 mg/ml) was displayed by the oils of A. deserticola, A. micrantha and L. buchtormensis on Septoria tritici and by the oil of A. deserticola on Septoria glycine. The antimicrobial activity was associated to the contents of ß-thujone, trans-sabinyl acetate and trans-sabinol. Our results indicate that the tested essential oils have little inhibitory potency not suitable for use as plant protection products against the phytopathogens assayed.


Assuntos
Achillea/química , Anti-Infecciosos/farmacologia , Apiaceae/química , Artemisia/química , Óleos Voláteis/farmacologia , Plantas Medicinais/química , Verbenaceae/química , Bactérias/efeitos dos fármacos , Fungos/efeitos dos fármacos , Óleos Voláteis/análise
10.
Antonie Van Leeuwenhoek ; 108(5): 1047-57, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26342699

RESUMO

The main secondary metabolite of Senecio nutans is 4-hydroxy-3-(3-methyl-2-butenyl)acetophenone (4HMBA). The antifungal activity of this compound and three derivatives was assessed using Candida albicans. 4HMBA exhibited the highest antifungal activity among the assayed compounds. The Fractional Inhibitory Concentration (FIC = 0.133) indicated a synergistic fungicidal effect of 4HMBA (5 mg L(-1)) and fluconazole (FLU) (0.5 mg L(-1)) against the C. albicans reference strain (ATCC 10231). Microscopy showed that 4HMBA inhibits filamentation and reduces cell wall thickness. Our findings suggest that 4HMBA is an interesting compound to diminish resistance to commercial fungistatic drugs such as fluconazole.


Assuntos
Acetofenonas/farmacologia , Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Acetofenonas/química , Antifúngicos/química , Candida albicans/ultraestrutura , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Relação Dose-Resposta a Droga , Viabilidade Microbiana/efeitos dos fármacos
11.
Nat Prod Commun ; 9(7): 1019-22, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25230518

RESUMO

The composition of the essential oils from leaves (Sal) and fruits of S. areira (Saf), and fruits of S. fasciculatus (Sff) and S. gracilipes (Sgf) were analyzed by GC/MS. The major compounds identified were sabinene (26.0 +/- 0.5%), bicyclogermacrene (14.5 +/- 0.4%), and E-citral (6.7+/- 0.2%) in Sal oil, limonene (27.7 +/- 0.7%), sabinene (16.0+/- 0.5%), beta-phellandrene (14.6 +/- 0.8%) and bicyclogermacrene (8.1 +/- 0.2%) in Saf oil, sabinene (22.7 +/- 0.6%), alpha-phellandrene (18.7 +/- 0.3%), beta-phellandrene (15.7 +/- 0.4%), and bicyclogermacrene (8.1 +/- 0.2%) in Sff oil and beta-pinene (25.4 +/- 0.8%), alpha-pinene (24.7 +/- 0.7%), and sabinene (13.6 +/- 0.4%) in Sgf oil.The antifungal activity of the four oils was evaluated on strains of Fusarium verticillioides and F. graminearum, and the results compared with the effect of epoxyconazole, pyraclostrobin and thyme oil. The Sff oil had the highest antifungal activity among the Schinus oils tested, with MIC100 (F. graminearum) = 6 per thousand and MIC100 (F. verticillioides) = 12 per thousand. A principal component analysis suggests that 9 constituents (alpha-thujene, alpha-terpinene, p-cymene, gamma-terpinene, terpinolene, 1-terpineol, alpha-calacorene, alpha-phellandrene, and terpinen-4-ol) explain the higher antifungal effect of Sff. The MIC100s of Schinus oils were on average 30-60 and 8.5-17 fold lower than those obtained for thyme oil on F. verticillioides and F. graminearum, respectively. In the case of commercial fungicides, their MIC100s were three orders of magnitude lower than those of Schinus oils. The last ones showed an additive interaction when assayed in mixtures with the commecial fungicides and thyme oil. The results suggest that the doses of fungicides required for control of the Fusarium species can be reduced when they are assayed in mixtures with the Schinus oils.


Assuntos
Anacardiaceae/química , Antifúngicos/química , Antifúngicos/farmacologia , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia , Argentina , Fusarium , Óleos de Plantas/química
12.
J Ethnopharmacol ; 147(1): 63-73, 2013 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-23415707

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Caesalpinia paraguariensis (D. Parodi) Burkart stem bark infusion (CPBI) is traditionally used in Argentina because their "vulnerary" properties. AIM OF THE STUDY: CPBI was studied throughout bio-guided purification procedures conducted by in vitro biological assays in order to isolate the main bioactive compounds. MATERIAL AND METHODS: Anti-inflammatory activity was assessed by enzyme inhibition assays of Hyaluronidase (Hyal) and inducible Nitric Oxide Synthase (iNOS). The antioxidant properties were evaluated by DPPH free radical scavenging assay, lipid peroxidation inhibition assay on erythrocyte membranes, and a cell-based assay that included the fluorescent probe (DCFH-DA) for indicating reactive oxygen species (ROS) generation. Bioactive compounds were purified by chromatographic methods and their structures elucidated using spectroscopic methods (ESI-MS and 1D/2D-(1)H/(13)C-NMR). RESULTS: Four main bioactive compounds were isolated from CPBI: ellagic acid (1), 3-O-methylellagic acid (2), 3,3'-di-O-methylellagic acid (3) and 3,3'-di-O-methylellagic-4-ß-D-xylopyranoside (4). These were bioactive at concentrations in which are present in CPBI, being compounds 2 and 3 the best enzyme inhibitors of Hyal and iNOS, reaching the 90% inhibitory concentration (IC90) values ranging from 2.8 to 16.4 µM, that are better than that of the positive controls, aspirin (IC90: no reached) and aminoguanidine (IC90: 20.2 µM) respectively. Compounds 2 and 3 were also better scavengers for lipoperoxides than butylated hydroxytoluene (BHT), reaching the 90% effective concentration (EC90) at 1.2-4.5 µg/ml, and for DPPH radical (2.5-7.3 µg/ml); moreover compounds were able to exert its scavenging action on intracellular ROS. Structural features relevant to the biological activities are discussed. CONCLUSIONS: This work provides scientific validity to the popular usage of CPBI.


Assuntos
Anti-Inflamatórios/farmacologia , Caesalpinia , Lactonas/farmacologia , Fenóis/farmacologia , Preparações de Plantas/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Antioxidantes/farmacologia , Bioensaio , Compostos de Bifenilo/química , Caesalpinia/química , Fracionamento Químico , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Membrana Eritrocítica/efeitos dos fármacos , Membrana Eritrocítica/metabolismo , Hialuronoglucosaminidase/antagonistas & inibidores , Hialuronoglucosaminidase/metabolismo , Lactonas/química , Lactonas/isolamento & purificação , Peroxidação de Lipídeos/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Estrutura Molecular , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II/metabolismo , Fenóis/química , Fenóis/isolamento & purificação , Fitoterapia , Picratos/química , Casca de Planta , Preparações de Plantas/química , Preparações de Plantas/isolamento & purificação , Caules de Planta , Plantas Medicinais , Espécies Reativas de Oxigênio/metabolismo , Espectrometria de Massas por Ionização por Electrospray , Relação Estrutura-Atividade
13.
Int J Food Microbiol ; 153(1-2): 229-33, 2012 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-22119268

RESUMO

Members of the Fusarium graminearum species complex (Fg complex) cause Gibberella ear rot in maize from northwest Argentina. The potential of these pathogens to contaminate maize grains with type B trichothecenes is a health risk for both humans and animals. We evaluated the reliability of multiplex PCR assays based on TRI3 and TRI12 genes, and single PCR assays based on TRI7 and TRI13 genes to infer trichothecene chemotypes of 112 strains of Fg complex collected from northwest Argentina, checking trichothecene production by chemical analysis. Single and multiplex PCR assays indicated that strains belonging to F. meridionale (87/112) had a NIV genotype. The remainder strains (25/112), which belonged to F. boothii, had a DON genotype (based on single PCR assays) or 15ADON genotype (based on multiplex PCR assays). No strains tested were incorrectly diagnosed with a DON/NIV genotype. Chemical analysis indicated that the F. meridionale strains were NIV producers only (44/87), major NIV producers with unexpected high DON/NIV ratios (36/87), or unexpected major DON producers with minor NIV production (7/87). Strains with atypical DON/NIV production seem to be new phenotypes under a putative NIV genotype, since PCR assays do not provide evidences of a new trichothecene genotype. DON production and absence of its acetylated forms were shown for strains of F. boothii. The inconsistencies between genetic and chemical data highlight the risk of inferring the trichothecenes potentially contaminating food and feedstuffs based only on PCR assays. This study confirms for the first time that strains of Fg complex from maize of northwest Argentina are DON and NIV producers. In addition, dominance of NIV producers in the Fg complex population isolated from maize is unprecedented in Argentina, and of significant concern to food safety and animal production.


Assuntos
Fusarium/genética , Tricotecenos/biossíntese , Zea mays/microbiologia , Argentina , Fusarium/isolamento & purificação , Fusarium/metabolismo , Genótipo , Reação em Cadeia da Polimerase Multiplex , Tricotecenos/análise , Tricotecenos/genética
14.
J Ethnopharmacol ; 130(2): 329-33, 2010 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-20488234

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Leaf extracts from Tripodanthus acutifolius (Ruiz and Pavón) Van Tieghem have long been used in Argentinean traditional medicine as anti-inflammatory, however, there is no scientific evidence which supports this use in the literature. AIM OF THE STUDY: The present study was conducted to evaluate the ability of five phenolic compounds purified from infusion prepared from Tripodanthus acutifolius leaves to inhibit key enzymes in inflammatory processes. As anti-inflammatory compounds frequently possess free radical scavenging activities, purified substances were comparatively evaluated to asses their free radical scavenging properties. Genotoxic effects were also evaluated. MATERIALS AND METHODS: Compounds were evaluated on their ability to inhibit hyaluronidase and cyclooxygenase-2 (COX-2) activities to assess their anti-inflammatory capacities. Free radical scavenging activity was assessed by: 1,1-diphenyl-2-picryl-hydrazyl radical (DPPH), superoxide anion assay and the inhibition on lipid peroxidation. Genotoxicity was evaluated by Bacillus subtilis rec assay. RESULTS: Fractionation of Tripodanthus acutifolius infusion yielded a novel phenylbutanoid derivative (tripodantoside) and four known flavonoid glycosides (rutin, nicotiflorin, hyperoside and isoquercitrin). Flavonoids produced higher inhibition on hyluronidase activity (IC(50) approximately 1.7 mM) than tripodantoside (IC(50)=27.90 mM). A similar COX-2 inhibition activity was exerted by tripodantoside and monoglycosilated flavonoids (IC(50) approximately 50 microM). Compounds were strong radical scavengers, with effective concentration 50 (EC(50)) values for DPPH in the range of 2.7-6.3 microg/mL, and for superoxide anion in the range of 3.9-8.7 microg/mL. All compounds scavenged peroxyl radicals in the lipid peroxidation assay. The substances showed no genotoxic effects. CONCLUSIONS: The anti-inflammatory effects, free radical scavenging activities and lack of genotoxicity of purified compounds may support the folk use of infusion from Tripodanthus acutifolius leaves as anti-inflammatory.


Assuntos
Anti-Inflamatórios/farmacologia , Inibidores de Ciclo-Oxigenase 2/farmacologia , Sequestradores de Radicais Livres/farmacologia , Loranthaceae , Fenóis/farmacologia , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/toxicidade , Bacillus subtilis/efeitos dos fármacos , Bacillus subtilis/genética , Compostos de Bifenilo/química , Bovinos , Ciclo-Oxigenase 2/metabolismo , Inibidores de Ciclo-Oxigenase 2/química , Inibidores de Ciclo-Oxigenase 2/isolamento & purificação , Inibidores de Ciclo-Oxigenase 2/toxicidade , Dano ao DNA , Relação Dose-Resposta a Droga , Flavonoides/farmacologia , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/isolamento & purificação , Sequestradores de Radicais Livres/toxicidade , Humanos , Hialuronoglucosaminidase/antagonistas & inibidores , Hialuronoglucosaminidase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fenóis/química , Fenóis/isolamento & purificação , Fenóis/toxicidade , Picratos/química , Folhas de Planta , Quercetina/análogos & derivados , Quercetina/farmacologia , Proteínas Recombinantes/metabolismo , Rutina/farmacologia
15.
Mycol Res ; 113(Pt 12): 1404-10, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19781642

RESUMO

The present work describes the purification and characterization of a novel extracellular polygalacturonase, PGase I, produced by Pycnoporus sanguineus when grown on citrus fruit pectin. This substrate gave enhanced enzyme production as compared to sucrose and lactose. PGase I is an exocellular enzyme releasing galacturonic acid as its principal hydrolysis product as determined by TLC and orcinol-sulphuric acid staining. Its capacity to hydrolyze digalacturonate identified PGase I as an exo-polygalacturonase. SDS-PAGE showed that PGase I is an N-glycosidated monomer. The enzyme has a molecular mass of 42kDa, optimum pH 4.8 and stability between pH 3.8 and 8.0. A temperature optimum was observed at 50-60 degrees C, with some enzyme activity retained up to 80 degrees C. Its activation energy was 5.352calmol(-1). PGase I showed a higher affinity towards PGA than citric pectin (Km=0.55+/-0.02 and 0.72+/-0.02mgml(-1), respectively). Consequently, PGase I is an exo-PGase, EC 3.2.1.82.


Assuntos
Glicosídeo Hidrolases/metabolismo , Poligalacturonase/metabolismo , Pycnoporus/enzimologia , Citrus/microbiologia , Meios de Cultura , Eletroforese em Gel de Poliacrilamida , Fermentação/genética , Frutas/microbiologia , Glicosídeo Hidrolases/genética , Glicosídeo Hidrolases/isolamento & purificação , Ácidos Hexurônicos/metabolismo , Concentração de Íons de Hidrogênio , Cinética , Peso Molecular , Pectinas/genética , Pectinas/isolamento & purificação , Pectinas/metabolismo , Poligalacturonase/genética , Poligalacturonase/isolamento & purificação , Análise de Sequência de DNA , Especificidade por Substrato , Temperatura
16.
Int J Food Microbiol ; 132(1): 42-6, 2009 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-19375811

RESUMO

The antifungal activity of the ethanolic extract (EE), (3R)-5,7,2',3'-tetrahydroxy-4'-methoxy-5'-prenylisoflavanone (1) and (3R)-7-2'-3'-trihydroxy-4'-methoxy-5'-prenylisoflavanone (2) isolated from Geoffroea decorticans was evaluated against four different species of Aspergillus. Their effect was compared with that displayed by synthetic products. The antifungal activity was assayed by bioautography, hyphal radial growth, hyphal extent and microdilution in liquid medium. The percentage of hyphal radial growth inhibition produced by EE varied between 18.4+/-0.1 and 39.6+/-0.2 for Aspergillus nomius VSC23 and Aspergillus nomius 13137, respectively; and the same value for 1 and 2 were between 31.2+/-0.1-60.8+/-1.5 and 28.9+/-0.7-57.2+/-0.6 for Aspergillus flavus (IEV 018) and Aspergillus nomius 13137, respectively. The values of MIC/MFC determined for EE, 1 and 2 were compared with the actions of ascorbic and sorbic acids, and clotrimazole. The sequence of antifungal potency was clotrimazole>1>2>ascorbic acid>sorbic acid>EE. Consequently, EE as well as the purified substances from Geoffroea decorticans would be used as biopesticides against Aspergillus species. The cytotoxicity was evaluated.


Assuntos
Ração Animal/microbiologia , Antifúngicos/farmacologia , Aspergillus/efeitos dos fármacos , Fabaceae/química , Isoflavonas/farmacologia , Animais , Artemia , Aspergillus/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Extratos Vegetais/farmacologia
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