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1.
Arch Gynecol Obstet ; 300(2): 293-297, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31069489

RESUMEN

OBJECTIVE: To assess the association of the attendant of the parturient (husband or mother or both), on labor duration, mode of delivery, maternal and neonatal complications. STUDY DESIGN: A retrospective cohort study, over a 4-year period, of women admitted to the delivery room accompanied by their husband, their mother or both. Medical records were reviewed for demographic, medical and obstetrical history. RESULTS: Overall, 3029 patients were included, 2192 were accompanied by their husband; 127 were accompanied by their mother and 710 were accompanied by both. Women accompanied by their husbands were significantly older and more likely to be multiparous than women accompanied by their mother (30.2 years vs. 27.8 years, P < 0.001 and 60% vs. 48.8%, P = 0.02, respectively). Compared to women supported during labor by their mothers, women supported only by their husbands spent less hours in the delivery room (from admission to delivery) (11.1 h vs. 13.7 h, P = 0.02). While the nature of the attendant had no influence on the mode of delivery among nulliparous women (p = 0.13), multiparous women supported by the mothers had a significantly higher rate of cesarean delivery compared to those supported only by their husband or by both (OR = 2.07, 95% CI = [1.317-3.246], P = 0.002, OR = 3.33, 95% CI = [1.623-6.849], P = 0.001, respectively). CONCLUSIONS: Women supported by their mothers during labor have a longer second stage of labor, a decreased rate of vaginal delivery and an increased risk for cesarean delivery compared to women supported by their husbands. Future large prospective studies are needed to confirm our observation and to find causative affect.


Asunto(s)
Cesárea/métodos , Salas de Parto/normas , Parto Obstétrico/métodos , Trabajo de Parto/fisiología , Adulto , Femenino , Humanos , Recién Nacido , Embarazo , Estudios Retrospectivos
2.
Front Microbiol ; 8: 984, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28634472

RESUMEN

Antimicrobial peptides (AMPs) are ubiquitous and multipotent components of the innate immune defense arsenal used by both prokaryotic and eukaryotic organisms. The search for new AMPs has increased in recent years, due to the growing development of microbial resistance to therapeutical drugs. In this work, we evaluate the effects of Tityus serrulatus venom (Tsv), its fractions and its major toxin Ts1, a beta-neurotoxin, on fungi growth. The fractions were obtained by ion-exchange chromatography of Tsv. The growth inhibition of 11 pathogenic and non-pathogenic filamentous fungi (Aspergillus fumigatus, A. nidulans, A. niger, A. terreus, Neurospora crassa, Penicillium corylophilum, P. ochrochloron, P. verrucosum, P. viridicatum, P. waksmanii, and Talaromyces flavus) was evaluated by quantitative microplate reader assay. Tsv (100 and 500 µg/well, which correspond to 1 and 5 mg/mL, respectively, of total soluble protein) was active in inhibiting growth of A. nidulans, A. terreus, P. corylophilum, and P. verrucosum, especially in the higher concentration used and at the first 30 h. After this period, fungi might have used Tsv components as alternative sources of nutrients, and therefore, increased their growth tax. Only fractions IX, X, XI, XIIA, XIIB (3 and 7.5 µg/well, which correspond to 30 and 75 µg/mL, respectively, of total soluble protein) and Ts1 (1.5, 3, and 6 µg/well, which correspond to 2.18, 4.36, and 8.72 µM, respectively) showed antifungal activity. Ts1 showed to be a non-morphogenic toxin with dose-dependent activity against A. nidulans, inhibiting 100% of fungal growth from 3 µg/well (4.36 µM). The inhibitory effect of Ts1 against A. nidulans growth was accompanied by fungistatic effects and was not amended by 1 mM CaCl2 or tetrodotoxin (46.98 and 93.96 µM). The structural differences between Ts1 and drosomycin, a potent cysteine-rich antifungal peptide, are discussed here. Our results highlight the antifungal potential of the first cysteine-containing scorpion toxin. Since Ts1 is a multifunctional toxin, we suggest that it could be used as a template in the design of engineered scorpion AMPs and in the search for new mechanisms of action of antifungal drugs.

3.
J Microencapsul ; 32(1): 16-21, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25198912

RESUMEN

Two simple procedures for the preparation of magnetic chitosan enzyme microparticles have been investigated and used for the immobilisation of endophytic fungus Cercospora kikuchii lipase as model enzyme. In the first case, lipase was entrapped in Fe3O4-chitosan microparticles by cross-linking method, while in the second case magnetic immobilised derivatives were produced using spray drying. Immobilised enzymes showed high enzyme activity retention and stability during storage without significant loss of activity. Glutaraldehyde Fe3O4-chitosan powders presented a higher lipase activity retention and storage stability than the others preparations. However, the immobilised derivatives produced by cross-linking showed higher enzyme activity after reuse cycles. The results proved that the magnetic Fe3O4-chitosan microparticles are an effective support for the enzyme immobilisation since the immobilised lipase showed best properties than the free form.


Asunto(s)
Ascomicetos/enzimología , Quitosano/química , Enzimas Inmovilizadas/química , Óxido Ferrosoférrico/química , Proteínas Fúngicas/química , Lipasa/química
4.
Braz. arch. biol. technol ; 57(4): 578-586, Jul-Aug/2014. tab, graf
Artículo en Inglés | LILACS | ID: lil-712932

RESUMEN

This work studied the immobilization of Cercospora kikuchii lipases on chitosan microparticles by chemical attachment on chitosan acetate microparticles activated by glutaraldehyde (CAM) added before or after the enzyme and physical adsorption on highly deacetylated chitosan hydrochloride microparticles (CHM). Lipases covalently immobilized on pre-activated CAM showed better performance retaining 88.4% of the enzymatic activity, with 68.2% of immobilization efficiency (IE). The immobilized enzyme retained an activity of about 53.5 % after five reuses, using p-NPP as substrate. Physical adsorption of lipase onto highly deacetylated CHM showed 46.2 % of enzymatic activity and 28.6% of IE. This immobilized derivative did not lose activity up to 80 days of storage at 4°C, while lipases immobilized on pre-activated CAM maintained its activity up to 180 days at same conditions. Taken together the results indicate that chitosan microparticles provide an optimal microenvironment for the immobilized enzyme to maintain good activity and stability.

5.
Phytochemistry ; 96: 92-100, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24135634

RESUMEN

Biotransformation of chemicals by microorganisms can be effective in increasing chemical diversity. Some fungi have been described to be useful for the biotransformation of sesquiterpene lactones. Nevertheless, in most cases, only minor or simple transformations of functional groups have been observed. Budlein A is a sesquiterpene lactone found in high amounts in American sunflower-like species of the genus Viguiera (Asteraceae). It shows important biological effects like in vitro and in vivo anti-inflammatory activity, as well as cytotoxicity against cancer cell lines. With the aim to obtain potentially bioactive derivatives of budlein A and taking into account that obtaining semi-synthetic analogues is a very complex task, the capability of soil fungi to promote biotransformation was investigated. In this work, the biotransformation of budlein A by the soil fungi Aspergillus terreus and A. niger affording three unusual sesquiterpenoid derivatives with carbon skeletons is reported. The chemical structures of the compounds were elucidated by 1D and 2D NMR spectrometry and HR-ESI-MS. The stereochemistry and molecular conformation of one derivative was assessed by molecular modeling techniques. The fungal metabolites displayed a reduced cytotoxicity against HL-60 cells when compared to the original natural product. The results show the versatility of microbial-catalyzed biotransformations leading to unusual derivatives.


Asunto(s)
Antiinflamatorios/metabolismo , Aspergillus/metabolismo , Lactonas/metabolismo , Sesquiterpenos/metabolismo , Aspergillus/crecimiento & desarrollo , Asteraceae/química , Asteraceae/metabolismo , Asteraceae/microbiología , Biotransformación , Detección Precoz del Cáncer , Células HL-60 , Humanos , Lactonas/química , Modelos Moleculares , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Sesquiterpenos/química , Microbiología del Suelo , Estereoisomerismo
6.
Bioorg Med Chem ; 21(18): 5870-5, 2013 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-23916147

RESUMEN

Microbial transformation stands out among the many possible semi-synthetic strategies employed to increase the variety of chemical structures that can be applied in the search for novel bioactive compounds. In this paper we obtained ent-pimaradienoic acid (1, PA, ent-pimara-8(14),15-dien-19-oic acid) derivatives by fungal biotransformation using Aspergillus niger strains. To assess the ability of such compounds to inhibit vascular smooth muscle contraction, we also investigated their spasmolytic effect, along with another five PA derivatives previously obtained in our laboratory, on aortic rings isolated from male Wistar rats. The microbial transformation experiments were conducted at 30°C using submerged shaken liquid culture (120 rpm) for 10 days. One known compound, 7α-hydroxy ent-pimara-8(14),15-dien-19-oic acid (2), and three new derivatives, 1ß-hydroxy ent-pimara-6,8(14),15-trien-19-oic acid (3), 1α,6ß,14ß-trihydroxy ent-pimara-7,15-dien-19-oic acid (4), and 1α,6ß,7α,11α-tetrahydroxy ent-pimara-8(14),15-dien-19-oic acid (5), were isolated and identified on the basis of spectroscopic analyses and computational studies. The compounds obtained through biotransformation (2-5) did not display a significant antispasmodic activity (values ranging from 0% to 16.8% of inhibition); however the previously obtained diterpene, methyl 7α-hydroxy ent-pimara-8(14),15-dien-19-oate (8), showed to be very effective (82.5% of inhibition). In addition, our biological results highlight the importance to study the antispasmodic potential of a large number of novel diterpenes, to conduct further structure-activity relationship investigations.


Asunto(s)
Aspergillus niger/metabolismo , Diterpenos/metabolismo , Animales , Aorta/efectos de los fármacos , Aorta/fisiología , Asteraceae/metabolismo , Biotransformación , Diterpenos/química , Diterpenos/farmacología , Espectroscopía de Resonancia Magnética , Masculino , Conformación Molecular , Contracción Muscular/efectos de los fármacos , Fenilefrina/farmacología , Ratas , Ratas Wistar , Estereoisomerismo , Relación Estructura-Actividad
7.
Nat Prod Res ; 27(23): 2240-3, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23805902

RESUMEN

Fractionation of extracts from the fermentation broth of the endophytic fungus Arthrinium state of Apiospora montagnei resulted in the isolation of the major secondary metabolites, R-(-)-mellein (1) and cis-(3R,4R)-4-hydroxymellein (2). The chemical structures of compounds were determined by spectroscopic analyses. The isolated compounds were tested in vitro to determine their activity against Schistosoma mansoni adult worms. Compounds 1 and 2 caused death of 100% of parasites at 200 and 50 µg mL(-1), respectively. Ultrastructural analysis suggested that the tegument can be a target of compound 1.


Asunto(s)
Ascomicetos/metabolismo , Isocumarinas/farmacología , Schistosoma mansoni/efectos de los fármacos , Animales , Medios de Cultivo , Evaluación Preclínica de Medicamentos , Femenino , Fermentación , Isocumarinas/química , Isocumarinas/metabolismo , Masculino
8.
Phytother Res ; 27(10): 1502-7, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23193079

RESUMEN

The present study describes the antimicrobial activity of five pimarane-type diterpenes obtained by fungal biotransformation against several nosocomial multidrug-resistant bacteria. Among the investigated metabolites, ent-8(14),15-pimaradien-3ß-ol was the most active compound, with very promising minimal inhibitory concentration values (between 8.0 and 25.0 µg mL(-1)). Time-kill assays using this metabolite against Staphylococcus aureus (HCRP180) revealed that this compound exerted its bactericidal effect within 24 h at all the evaluated concentrations (8.0, 16.0, and 24.0 µg mL(-1)). When this metabolite was associated with vancomycin at their minimal bactericidal concentration values, the resulting combination was able to drastically reduce the number of viable strains of S. aureus within the first 6 h, compared with these chemicals alone. The checkerboard assays conducted against this microorganism did not evidence any synergistic effects when this same combination was employed. In conclusion, our results point out that ent-8(14),15-pimaradien-3ß-ol is an important metabolite in the search for new effective antimicrobial agents.


Asunto(s)
Abietanos/farmacología , Antibacterianos/farmacología , Staphylococcus aureus/efectos de los fármacos , Abietanos/química , Abietanos/aislamiento & purificación , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Aspergillus ochraceus/metabolismo , Asteraceae/química , Biotransformación , Farmacorresistencia Bacteriana Múltiple , Pruebas de Sensibilidad Microbiana , Raíces de Plantas/química , Vancomicina/farmacología
9.
Chem Biodivers ; 9(8): 1465-74, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22899607

RESUMEN

The schistosomicidal effects of pimaradienoic acid (PA) and two derivatives, obtained by fungal transformation in the presence of Aspergillus ochraceus, were investigated. PA was the only compound with antischistosomal activity among the three diterpenes studied, with the ability to significantly reduce the viability of the parasites at concentrations ranging from 25 to 100 µM. PA also promoted morphological alterations of the tegument of Schistosoma mansoni, separated all the worm couples, and affected the production and development of eggs. Moreover, this compound was devoid of toxicity toward human fibroblasts. In a preliminary in vivo experiment, PA at a dose of 100 mg/kg significantly diminished the number of parasites in infected Balb/c mice. Taken together, these results show that PA may be potentially employed in the discovery of novel schistosomicidal agents, and that diterpenes are an important class of natural compounds for the investigation of agents capable of fighting the parasite responsible for human schistosomiasis.


Asunto(s)
Aspergillus ochraceus/metabolismo , Diterpenos/metabolismo , Diterpenos/uso terapéutico , Schistosoma mansoni/efectos de los fármacos , Esquistosomiasis mansoni/tratamiento farmacológico , Esquistosomicidas/metabolismo , Esquistosomicidas/uso terapéutico , Animales , Asteraceae/química , Biotransformación , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Diterpenos/química , Diterpenos/farmacología , Fibroblastos/efectos de los fármacos , Humanos , Ratones , Ratones Endogámicos BALB C , Extractos Vegetales/química , Extractos Vegetales/metabolismo , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Schistosoma mansoni/crecimiento & desarrollo , Esquistosomiasis mansoni/parasitología , Esquistosomicidas/química , Esquistosomicidas/farmacología
10.
J Ind Microbiol Biotechnol ; 39(11): 1719-24, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22782617

RESUMEN

The biotransformation of the sesquiterpene lactone tagitinin C by the fungus Aspergillus terreus MT 5.3 yielded a rare derivative that was elucidated by spectrometric methods. The fungus led to the formation of a different product through an unusual epoxidation reaction between C4 and C5, formation of a C3,C10 ether bridge, and a methoxylation of the C1 of tagitinin C. The chemical structure of the product, namely 1ß-methoxy-3α-hydroxy-3,10ß-4,5α-diepoxy-8ß-isobutyroyloxygermacr-11(13)-en-6α,12-olide, is the same as that of a derivative that was recently isolated from the flowers of a Brazilian population of Mexican sunflower (Tithonia diversifolia), which is the source of the substrate tagitinin C. The in vitro cytotoxic activity of the substrate and the biotransformed product were evaluated in HL-60 cells using an MTT assay, and both compounds were found to be cytotoxic. We show that soil fungi may be useful in the biotransformation of sesquiterpene lactones, thereby leading to unusual changes in their chemical structures that may preserve or alter their biological activities, and may also mimic plant biosynthetic pathways for production of secondary metabolites.


Asunto(s)
Aspergillus/metabolismo , Lactonas/metabolismo , Sesquiterpenos/metabolismo , Asteraceae/química , Asteraceae/metabolismo , Vías Biosintéticas , Biotransformación , Brasil , Células HL-60 , Humanos , Lactonas/química , Lactonas/aislamiento & purificación , Lactonas/toxicidad , Sesquiterpenos/química , Sesquiterpenos/aislamiento & purificación , Sesquiterpenos/toxicidad , Microbiología del Suelo
11.
Can J Microbiol ; 57(7): 611-6, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21770720

RESUMEN

In this work, we disrupted one of three putative phosphatidylinositol phospholipase C genes of Aspergillus nidulans and studied its effect on carbon source sensing linked to vegetative mitotic nuclear division. We showed that glucose does not affect nuclear division rates during early vegetative conidial germination (6-7 h) in either the wild type or the plcA-deficient mutant. Only after 8 h of cultivation on glucose did the mutant strain present some decrease in nuclear duplication. However, decreased nuclear division rates were observed in the wild type when cultivated in media amended with polypectate, whereas our plcA-deficient mutant did not show slow nuclear duplication rates when grown on this carbon source, even though it requires induction and secretion of multiple pectinolytic enzymes to be metabolized. Thus, plcA appears to be directly linked to high-molecular-weight carbon source sensing.


Asunto(s)
Aspergillus nidulans/enzimología , Carbono/metabolismo , División del Núcleo Celular , Proteínas Fúngicas/fisiología , Fosfoinositido Fosfolipasa C/fisiología , Aspergillus nidulans/genética , Aspergillus nidulans/metabolismo , Núcleo Celular/metabolismo , Proteínas Fúngicas/genética , Glucosa/metabolismo , Fosfoinositido Fosfolipasa C/genética , Esporas Fúngicas/crecimiento & desarrollo
12.
Molecules ; 15(12): 8553-66, 2010 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-21116225

RESUMEN

In the present work, the anticariogenic activities of three pimarane-type diterpenes obtained by fungal biotransformation were investigated. Among these metabolites, ent-8(14),15-pimaradien-19-ol was the most active compound, displaying very promising MIC values (ranging from 1.5 to 4.0 µg mL(-1)) against the main microorganisms responsible for dental caries: Streptococcus salivarius, S. sobrinus, S. mutans, S. mitis, S. sanguinis, and Lactobacillus casei. Time kill assays performed with ent-8(14),15-pimaradien-19-ol against the primary causative agent S. mutans revealed that this compound only avoids growth of the inoculum in the first 12 h (bacteriostatic effect). However, its bactericidal effect is clearly noted thereafter (between 12 and 24 h). The curve profile obtained by combining ent-8(14),15-pimaradien-19-ol and chlorhexidine revealed a significant reduction in the time necessary for killing S. mutans compared with each of these two chemicals alone. However, no synergistic effect was observed using the same combination in the checkerboard assays against this microorganism. In conclusion, our results point out that ent-8(14),15-pimaradien-19-ol is an important metabolite in the search for new effective anticariogenic agents.


Asunto(s)
Abietanos/farmacología , Antibacterianos/farmacología , Caries Dental/tratamiento farmacológico , Hongos , Bacterias Gramnegativas/crecimiento & desarrollo , Abietanos/química , Antibacterianos/química , Caries Dental/microbiología , Humanos
13.
Braz. arch. biol. technol ; 53(3): 629-632, May-June 2010. tab
Artículo en Inglés | LILACS | ID: lil-548584

RESUMEN

Papulaspora immersa and Arthrinium state of Apiospora montagnei Sacc. were isolated from the roots of Smallanthus sonchifolius (yacón). The crude extracts from their cultures inhibited the growth of Staphylococcus aureus, Kocuria rhizophila, Pseudomonas aeruginosa and Escherichia coli. The more relevant results were observed in the ethyl acetate extract from P immersa against P aeruginosa (90 µg/mL) and ethyl acetate extract from Arthrinium state of A montagnei Sacc. against P aeruginosa (160 µg/mL). The two endophytic fungi isolated from yacón roots as well as their antimicrobial activity detected in the crude extracts cultures were being reported for the first time.


Mesmo havendo grandes investimentos, a resistência a fármacos continua sendo um grave problema de saúde pública. Produtos naturais têm prevalecido como a maior fonte de novas drogas e muitos deles são isolados de sistemas simbióticos: microorganismos-plantas. Os fungos endofíticos Papulaspora immersa e Arthrinium state of Apiospora montagnei Sacc. foram isolados de raízes de Smallanthus sonchifolius (yacón). Extratos de culturas destes fungos apresentaram atividade antibacteriana frente Staphylococcus aureus, Kocuria rhizophila, Pseudomonas aeruginosa e Escherichia coli, sendo as mais relevantes observadas nas frações acetato de etila provenientes dos fungos P. immersa e Arthrinium state of Apiospora montagnei Sacc. frente a P. aeruginosa, apresentando CIM de 90µg/mL e 160µg/mL, respectivamente.

14.
Microbiol Res ; 161(3): 273-80, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16765844

RESUMEN

A Brazilian strain of Penicillium verrucosum was cultivated under different conditions in a two-step process, in order to verify the influence of nutrients, and of time periods of pre-fermentative and fermentative steps on the biosynthesis of metabolites. Extracellular and intracellular extracts were obtained from each culture in the four different production media used. Chemical profiles of the extracts were obtained by HPLC. Extract trypanocidal activities against trypomastigote forms of Trypanosoma cruzi were evaluated. The time period of incubation in the pre-fermentative and fermentative media, as well as the different nutrients tested, qualitatively and quantitatively modified the production of secondary metabolites by P. verrucosum, and the extract trypanocidal activities.


Asunto(s)
Antiprotozoarios/metabolismo , Productos Biológicos/metabolismo , Penicillium/crecimiento & desarrollo , Penicillium/metabolismo , Animales , Antiprotozoarios/aislamiento & purificación , Antiprotozoarios/farmacología , Cromatografía Líquida de Alta Presión , Medios de Cultivo , Metanol , Micelio/crecimiento & desarrollo , Micelio/metabolismo , Sonicación , Factores de Tiempo , Trypanosoma cruzi/efectos de los fármacos
15.
Braz. j. microbiol ; 36(2): 190-195, Apr.-June 2005. ilus, graf
Artículo en Inglés | LILACS | ID: lil-421724

RESUMEN

Os efeitos de compostos benzênicos de plantas, respectivamente ácido cinâmico, ácido coumárico, ácido ferúlico, ácido cafeico e aldeído cinâmico, sobre o crescimento da colônia e a morfologia das hifas de Neurospora crassa foram investigados. Acido cinâmico, ácido ferúlico e aldeído cinâmico inibiram o crescimento colonial, mas não produziram diferencas visíveis sobre as hifas. Acido cafeico e ácido coumárico não inibiram o crescimento, mas alteraram a morfologia das hifas. Os resultados sugerem que os ácidos cafeico e coumárico afetam provavelmente a manutencão da polaridade (a contínua deposicão de material da parede na ponta em extensão), enquanto aldeído cinâmico e os ácidos cinâmicos e ferúlico diminuem a velocidade de crescimento, mas não alteram a polaridade das hifas. Actina no citoesqueleto e no Spitzenkõrper apareceu difuso e não estava claramente visível na presenca de um dos compostos benzênicos na cultura.


Asunto(s)
Benceno/química , Hifa/crecimiento & desarrollo , Técnicas In Vitro , Neurospora crassa , Benceno/farmacología , Neurospora crassa
16.
J Basic Microbiol ; 45(3): 199-206, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15900541

RESUMEN

Hyphal tip growth is a highly polarized process of cell extension, which may be affected by chemical and physical stress. Neurospora crassa exposed to cold-shock lost its polarized growth and dichotomous branches were detected. These effects were not observed in the presence of 500 mM Ca2+. We compared here the morphological pattern of a snow-flake mutant (sn) and the wild-type (wt) exposed to 4 degrees C. Hyphal morphology, nuclei, actin and microtubule distribution were analyzed. No effects on sn hyphal morphology were detected at 4 degrees C. Exogenous Ca2+ converted sn to an essentially wt appearance. The results presented here suggest that sn mutation and cold-shock treatment have affected Ca2+ influx since addition of this cation to sn (30 degrees C) and to wt (4 degrees C) maintained polarized growth and normal nuclear and microtubules distribution.


Asunto(s)
Calcio/metabolismo , Neurospora crassa/citología , Neurospora crassa/crecimiento & desarrollo , Actinas/ultraestructura , Calcio/farmacología , Núcleo Celular/ultraestructura , Polaridad Celular , Frío , Hifa/citología , Hifa/crecimiento & desarrollo , Microtúbulos/ultraestructura , Morfogénesis/efectos de los fármacos , Morfogénesis/genética , Mutación , Neurospora crassa/genética , Neurospora crassa/metabolismo
17.
Microbiol Res ; 159(4): 317-22, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15646377

RESUMEN

A strain of Penicillium corylophilum isolated from Brazilian soil sample was submitted to different culture conditions to investigate the production of secondary metabolites with antimicrobial activity. The largest number of conidia was obtained after 5 days of incubation in oat medium and the highest level of antimicrobial activity was produced when the fungus culture was developed in the Czapek medium. The activity against Staphylococcus aureus was found only in the chloroform extract from Czapek culture broth, which also showed activity against Micrococcus luteus. Fumiquinozoline F was isolated from the active chloroform extract by using chromatographic methods. The minimal inhibitory concentration (MIC) values for M. luteus and S. aureus were 99 microg/ mL and 137microg/mL, respectively.


Asunto(s)
Antibacterianos/biosíntesis , Penicillium/metabolismo , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Brasil , Medios de Cultivo/química , Fermentación , Pruebas de Sensibilidad Microbiana , Micrococcus luteus/efectos de los fármacos , Estructura Molecular , Penicillium/crecimiento & desarrollo , Penicillium/aislamiento & purificación , Microbiología del Suelo , Staphylococcus aureus/efectos de los fármacos
18.
J Basic Microbiol ; 42(6): 381-7, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12442300

RESUMEN

The effects of cold-shock on Neurospora crassa was here investigated. In cold-shock treated hyphae (6 h at 4 degrees C) the branching pattern was changed and dichotomy as well as a fan-like-pattern structure were temporarily detected at the tips. When exogenous Ca(2+) (500 mM) was added to the hyphae, these morphological alterations were not detected. In addition, the protein electrophoretic profile of cultures submitted to cold-shock was different from that of cultures kept at 30 degrees C. After 1 and 2 hours at 4 degrees C at least 5 bands were more intense than at 30 degrees C. The results suggest that cold-shock temporarily increases the synthesis of some proteins probably involved in the acclimatization process at 4 degrees C, and that the effects on morphology are probably due to damage to calcium influx.


Asunto(s)
Frío , Neurospora crassa/citología , Calcio/metabolismo , Electroforesis en Gel de Poliacrilamida , Proteínas Fúngicas/análisis , Hifa/citología , Hifa/crecimiento & desarrollo , Micelio/aislamiento & purificación , Neurospora crassa/química , Neurospora crassa/crecimiento & desarrollo , Factores de Tiempo
19.
Microbiol Res ; 157(3): 207-11, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12398291

RESUMEN

In a screening program for new antibiotic producers, a strain of Aspergillus fumigatus was isolated from Brazilian soil samples. A pool of autoclaved bacteria was added to part of the fungus culture on the second day of fermentation to increase antibiotic production. The chloroform extract from the culture broth to which the pool of autoclaved bacteria was added showed an increase of 55%, 63% and more than 100% in activity against Staphylococcus aureus, Candida albicans and Micrococcus luteus, respectively. Also, the HPLC chromatographic profiles of the chloroform extracts from both culture conditions were different. Two active compounds were isolated from the broth of the culture grown in the presence of pooled bacteria and were identified as 3,4-dimethoxyphenol and 1,3,5-trimethoxybenzene.


Asunto(s)
Antibacterianos/farmacología , Aspergillus fumigatus/metabolismo , Antibacterianos/biosíntesis , Aspergillus fumigatus/efectos de los fármacos , Aspergillus fumigatus/crecimiento & desarrollo , Vacunas Bacterianas/administración & dosificación , Brasil , Candida albicans/efectos de los fármacos , Micrococcus luteus/efectos de los fármacos , Micelio/efectos de los fármacos , Micelio/crecimiento & desarrollo , Micelio/metabolismo , Microbiología del Suelo , Staphylococcus aureus/efectos de los fármacos
20.
Microbiol Res ; 157(3): 201-6, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12398290

RESUMEN

The conditions for the sequential production of antibiotic activity by Talaromyces flavus were determined. The highest level of activity against Trypanosoma cruzi was obtained from the aqueous extract of the Czapeck's fermentative culture after 48 hours, with lysis of 97.58% of the trypomastigote forms of Trypanosoma cruzi (red blood cells remained normal). The antimicrobial activity was detected in the extracts of fermentative cultures from different media just after 144 hours of incubation. Maximum activities against Micrococcus luteus, Staphylococcus aureus and Candida albicans were present in chloroform, butanolic and water extracts, in this order, when Talaromyces flavus was cultivated at pH 5.0. The minimal inhibitory concentration (MIC) of extracts of Takeuchi's cultures were determined.


Asunto(s)
Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Candida albicans/efectos de los fármacos , Talaromyces/química , Trypanosoma cruzi/efectos de los fármacos , Animales , Antibacterianos/biosíntesis , Glucosa Oxidasa/metabolismo , Concentración de Iones de Hidrógeno , Pruebas de Sensibilidad Microbiana , Micrococcus luteus/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Talaromyces/enzimología , Talaromyces/metabolismo , Factores de Tiempo
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