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1.
BMC Evol Biol ; 19(1): 98, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-31064342

RESUMO

BACKGROUND: The Micronycterinae form a subfamily of leaf-nosed bats (Phyllostomidae) that contains the genera Lampronycteris Sanborn, 1949, and Micronycteris Gray, 1866 (stricto sensu), and is characterized by marked karyotypic variability and discrepancies in the phylogenetic relationships suggested by the molecular versus morphological data. In the present study, we investigated the chromosomal evolution of the Micronycterinae using classical cytogenetics and multidirectional chromosome painting with whole-chromosomes probes of Phyllostomus hastatus and Carollia brevicauda. Our goal was to perform comparative chromosome mapping between the genera of this subfamily and explore the potential for using chromosomal rearrangements as phylogenetic markers. RESULTS: The Micronycterinae exhibit great inter- and intraspecific karyotype diversity, with large blocks of telomere-like sequences inserted within or adjacent to constitutive heterochromatin regions. The phylogenetic results generated from our chromosomal data revealed that the Micronycterinae hold a basal position in the phylogenetic tree of the Phyllostomidae. Molecular cytogenetic data confirmed that there is a low degree of karyotype similarity between Lampronycteris and Micronycteris specimens analyzed, indicating an absence of synapomorphic associations in Micronycterinae. CONCLUSIONS: We herein confirm that karyotypic variability is present in subfamily Micronycterinae. We further report intraspecific variation and describe a new cytotype in M. megalotis. The cytogenetic data show that this group typically has large blocks of interstitial telomeric sequences that do not appear to be correlated with chromosomal rearrangement events. Phylogenetic analysis using chromosome data recovered the basal position for Micronycterinae, but did not demonstrate that it is a monophyletic lineage, due to the absence of common chromosomal synapomorphy between the genera. These findings may be related to an increase in the rate of chromosomal evolution during the time period that separates Lampronycteris from Micronycteris.


Assuntos
Quirópteros/classificação , Quirópteros/genética , Evolução Molecular , Cariótipo , Filogenia , Animais , Teorema de Bayes , Mapeamento Cromossômico , Coloração Cromossômica/métodos , Cromossomos de Mamíferos/genética
2.
Carbohydr Polym ; 201: 31-38, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-30241824

RESUMO

An integrated process enabling the simultaneous production and purification of fructo-oligosaccharides (FOS) was explored. A co-culture fermentation with Aspergillus ibericus (used as FOS producer strain) and Saccharomyces cerevisiae YIL162 W (for small saccharides removal) was optimized. Inoculation conditions of S. cerevisiae, fermentative broth composition, temperature and pH were optimized by experimental design. Yeast extract concentration and temperature were the most significant variables affecting FOS purity. Co-culture fermentations with simultaneously inoculation of the strains, run under 30 °C, initial pH 6.0 and 17 g L-1 yeast extract led to FOS mixtures with 97.4 ± 0.2% (w/w) purity. The fermentations conducted in bioreactor, at a 0.8 vvm aeration rate, yielded 0.70 ± 0.00 gFOS.ginitial GF-1 at 45 h fermentation, with a FOS content of 133.7 ± 0.1 g L-1. A purity of FOS up to 93.8 ± 0.7% (w/w) was achieved. The one-step fermentation proved to be efficient, economical and fast.

3.
Int J Biol Macromol ; 109: 971-979, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29162463

RESUMO

The antimicrobial and anti-adhesive activities of the cell-bound biosurfactants, produced by Lactobacillus pentosus (PEB), characterized as glycolipopeptide macromolecules, were evaluated against several microorganisms present in the skin microflora, envisaging its potential use as a "natural" ingredient in cosmetic and personal care formulations. Their performance was compared with another cell-bound biosurfactants also characterized as glycolipopeptides produced by Lactobacillus paracasei (PAB). At concentrations of 50mg/mL, the PEB showed an important antimicrobial activity against Pseudomonas aeruginosa (85% when extracted with phosphate buffer (PB) and 100% when extracted with phosphate buffer saline (PBS)), Streptococcus agalactiae (100% for both extracts), Staphylococcus aureus (67% when extracted with PBS and 100% when extracted with PB), Escherichia coli (72% when extracted with PB and 89% when extracted with PBS), Streptococcus pyogenes (about 85% for both extracts) and Candida albicans (around 70% for both extracts), comparable with that obtained for the PAB. However, at lower concentrations the PAB exhibited in general higher antimicrobial activities. Biosurfactants produced by both microorganisms also showed significant anti-adhesive properties against all the microorganisms under study, except for E. coli and C. albicans (less than 30%). Overall, these cell-bound biosurfactants could be used as potential antimicrobial and anti-adhesive agents in cosmetic and pharmaceutical formulations.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Lipopeptídeos/química , Lipopeptídeos/farmacologia , Tensoativos/química , Tensoativos/farmacologia , Aderência Bacteriana/efeitos dos fármacos , Glicosilação , Lactobacillus/efeitos dos fármacos , Testes de Sensibilidade Microbiana
4.
Colloids Surf B Biointerfaces ; 155: 522-529, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28494430

RESUMO

Cosmetic and personal care products including toothpaste, shampoo, creams, makeup, among others, are usually formulated with petroleum-based surfactants, although in the last years the consume trend for "green" products is inducing the replacement of surface-active agents in these formulations by natural surfactants, so-called biosurfactants. In addition to their surfactant capacity, many biosurfactants can act as good emulsifiers, which is an extra advantage in the preparation of green cosmetic products. In this work, a biosurfactant obtained from Lactobacillus paracasei was used as a stabilizing agent in oil-in-water emulsions containing essential oils and natural antioxidant extract. In the presence of biosurfactant, maximum percentages of emulsion volumes (EV=100%) were observed, with droplets sizes about 199nm. These results were comparable with the ones obtained using sodium dodecyl sulfate (SDS), a synthetic well known surfactant with high emulsify capacity. Moreover, the biosurfactant and emulsions cytotoxicity was evaluated using a mouse fibroblast cell line. Solutions containing 5g/L of biosurfactant presented cell proliferation values of 97%, whereas 0.5g/L of SDS showed a strong inhibitory effect. Overall, the results herein gathered are very promising towards the development of new green cosmetic formulations.


Assuntos
Produtos Biológicos/química , Cosméticos/química , Lacticaseibacillus paracasei/química , Tensoativos/química , Células 3T3 , Animais , Antioxidantes/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Emulsificantes/química , Emulsificantes/farmacologia , Emulsões/química , Emulsões/farmacologia , Camundongos , Óleos Voláteis/química , Dodecilsulfato de Sódio/química , Dodecilsulfato de Sódio/farmacologia
5.
Crit Rev Biotechnol ; 37(7): 911-923, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28076995

RESUMO

Cosmetic products play an essential role in everyone's life. People everyday use a large variety of cosmetic products such as soap, shampoo, toothpaste, deodorant, skin care, perfume, make-up, among others. The cosmetic industry encompasses several environmental, social and economic impacts that are being addressed through the search for more efficient manufacturing techniques, the reduction of waste and emissions and the promotion of personal hygiene, contributing to an improvement of public health and at the same time providing employment opportunities. The current trend among consumers is the pursuit for natural ingredients in cosmetic products, as many of these products exhibit equal, better or additional benefits in comparison with the chemical-based products. In this sense, biosurfactants are natural compounds with great potential in the formulation of cosmetic products given by their biodegradability and impact in health. Indeed, many of these biosurfactants could exhibit a "prebiotic" character. This review covers the current state-of-the-art of biosurfactant research for cosmetic purposes and further discusses the future challenges for cosmetic applications.


Assuntos
Cosméticos , Indústrias , Tensoativos
6.
N Biotechnol ; 34: 59-67, 2017 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-27167856

RESUMO

Butanol and 1,3-propanediol (1,3-PDO) are simultaneously produced by Clostridium pasteurianum from glycerol. In this study, random chemical mutagenesis of C. pasteurianum DSM 525 was conducted to improve its tolerance to butanol. Selected nutritional and operational parameters were evaluated to identify strategies that favour the production of each metabolite. From those experiments, it was possible to isolate cells able to produce 22% more butanol than the parent strain in serum bottles. The supplementation of the culture medium with 2mgl-1 of iron increased the production of butanol by 163%, and the optimum inoculum age was found to be 12hours. Overall, the experiments conducted in bioreactor led to lower butanol titers than in serum bottles, which is attributed to the higher pressure present in the bottles. At pH 6.0, N2 sparging notoriously favoured the production of biomass and 1,3-PDO, while a lower pH (5.0) led to a higher butanol yield, although growth was negatively affected. The results herein gathered allowed the identification of specific conditions that favour the production of either butanol or 1,3-PDO. Furthermore, it was found that N2 sparging is a suitable strategy to maximize the titer, yield and productivity of 1,3-PDO using C. pasteurianum.


Assuntos
Butanóis/metabolismo , Clostridium/metabolismo , Propilenoglicóis/metabolismo , Biomassa , Reatores Biológicos/microbiologia , Biotecnologia , Clostridium/genética , Fermentação , Glicerol/metabolismo , Microbiologia Industrial , Ferro/metabolismo , Cinética , Redes e Vias Metabólicas , Mutagênese , Mutação
7.
J Fish Biol ; 89(1): 315-36, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27278087

RESUMO

The Patos Lagoon basin is a large (201 626 km(2) ) and complex drainage system in southern Brazil. The lagoon is 250 km long and 60 km wide, covering an area of 10 360 km(2) . The exchange of water with the Atlantic Ocean occurs through a 0·8 km wide and 15 m deep inlet, fixed by 4 km long jetties, at the southernmost part of the Patos Lagoon. The estuarine area is restricted to its southern portion (10%), although the upper limit of saline waters migrates seasonally and year to year, influenced by the wind regime and river discharge. The known number of recorded limnetic fish species is 200, but this number is expected to increase. A higher endemism is observed in fish species occurring in upper tributaries. The basin suffers from the direct impact of almost 7 million inhabitants, concentrated in small to large cities, most with untreated domestic effluents. There are at least 16 non-native species recorded in natural habitats of the Patos Lagoon basin, about half of these being from other South American river basins. Concerning the fishery, although sport and commercial fisheries are widespread throughout the Patos Lagoon basin, the lagoon itself and the estuarine area are the main fishing areas. Landing statistics are not available on a regular basis or for the whole basin. The fishery in the northern Patos Lagoon captures 31 different species, nine of which are responsible for most of the commercial catches, but only three species are actually sustaining the artisanal fishery: the viola Loricariichthys anus: 455 kg per 10 000 m(2) gillnet per day, the mullet Mugil liza: 123 kg per 10 000 m(2) gillnet per day and the marine catfish Genidens barbus: 50 kg per 10 000 m(2) gillnet per day. A decline of the fish stocks can be attributed to inadequate fishery surveillance, which leads to overfishing and mortality of juveniles, or to decreasing water quality because of urban and industrial activities and power production. Global climatic changes also represent a major threat to the Patos system by changing the frequency of El Niño-La Niña-Southern Oscillation (ENSO).


Assuntos
Conservação dos Recursos Naturais , Peixes , Animais , Oceano Atlântico , Brasil , Ecossistema , El Niño Oscilação Sul , Pesqueiros , Espécies Introduzidas , Rios , Smegmamorpha
8.
Carbohydr Polym ; 136: 274-81, 2016 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-26572356

RESUMO

Fructo-oligosaccharides (FOS) obtained by fermentation of sucrose may be purified at large-scale by continuous chromatography (Simulated Moving Bed: SMB). In order to improve the efficiency of the subsequent SMB purification, the optimization of the fermentative broth composition in salts and sugars was investigated. Fermentations conducted at reduced amount of salts, using Aureobasidium pullulans whole cells, yielded 0.63 ± 0.03 g of FOS per gram of initial sucrose. Additionally, a microbial treatment was proposed to reduce the amount of small saccharides in the mixture. Two approaches were evaluated, namely a co-culture of A. pullulans with Saccharomyces cerevisiae; and a two-step fermentation in which FOS were first synthesized by A. pullulans and then the small saccharides were metabolized by S. cerevisiae. Assays were performed in 100mL shaken flasks and further scaled-up to a 3 L working volume bioreactor. Fermentations in two-step were found to be more efficient than the co-culture ones. FOS were obtained with a purity of 81.6 ± 0.8% (w/w), on a dry weight basis, after the second-step fermentation with S. cerevisiae. The sucrose amount was reduced from 13.5 to 5.4% in total sugars, which suggests that FOS from this culture broth will be more efficiently separated by SMB.


Assuntos
Ascomicetos/metabolismo , Biotecnologia/métodos , Fermentação , Frutose/química , Oligossacarídeos/biossíntese , Oligossacarídeos/química , Saccharomyces cerevisiae/metabolismo , Ascomicetos/citologia , Técnicas de Cocultura , Saccharomyces cerevisiae/citologia
9.
Genet Mol Res ; 14(2): 5123-6, 2015 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-26125704

RESUMO

The Amazon pellona is one of the few species of Pristigasteridae with recognized commercial value in the Amazon. We isolated 24 and characterized 8 microsatellite loci for this species. The number of alleles ranges from 2-8 per locus. Observed heterozygosities ranged from 0.052-0.823, while expected heterozygosities from 0.052-0.836. These 8 microsatellites are potentially valuable tools for characterizing the levels and distribution of genetic diversity, population structure, and gene flow. They may also be important parameters for the genetic conservation of this species, as well as for its sister taxon Pellona flavipinnis.


Assuntos
Conservação dos Recursos Naturais , Peixes/genética , Loci Gênicos , Repetições de Microssatélites , Alelos , Animais , Brasil , Peixes/classificação , Fluxo Gênico , Variação Genética , Genética Populacional , Heterozigoto , Filogenia
10.
Enzyme Microb Technol ; 71: 36-44, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25765308

RESUMO

Caffeic acid is a plant secondary metabolite and its biological synthesis has attracted increased attention due to its beneficial effects on human health. In this study, Escherichia coli was engineered for the production of caffeic acid using tyrosine as the initial precursor of the pathway. The pathway design included tyrosine ammonia lyase (TAL) from Rhodotorula glutinis to convert tyrosine to p-coumaric acid and 4-coumarate 3-hydroxylase (C3H) from Saccharothrix espanaensis or cytochrome P450 CYP199A2 from Rhodopseudomonas palustris to convert p-coumaric acid to caffeic acid. The genes were codon-optimized and different combinations of plasmids were used to improve the titer of caffeic acid. TAL was able to efficiently convert 3mM of tyrosine to p-coumaric acid with the highest production obtained being 2.62mM (472mg/L). CYP199A2 exhibited higher catalytic activity towards p-coumaric acid than C3H. The highest caffeic acid production obtained using TAL and CYP199A2 and TAL and C3H was 1.56mM (280mg/L) and 1mM (180mg/L), respectively. This is the first study that shows caffeic acid production using CYP199A2 and tyrosine as the initial precursor. This study suggests the possibility of further producing more complex plant secondary metabolites like flavonoids and curcuminoids.


Assuntos
Ácidos Cafeicos/metabolismo , Escherichia coli K12/metabolismo , Tirosina/metabolismo , Actinobacteria/enzimologia , Actinobacteria/genética , Amônia-Liases/genética , Amônia-Liases/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Sequência de Bases , Vias Biossintéticas , Ácidos Cumáricos/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , DNA Bacteriano/genética , Escherichia coli K12/genética , Genes Bacterianos , Engenharia Genética , Dados de Sequência Molecular , Propionatos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Rodopseudomonas/enzimologia , Rodopseudomonas/genética , Rhodotorula/enzimologia , Rhodotorula/genética
11.
Microbiol Mol Biol Rev ; 79(1): 39-60, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25631288

RESUMO

SUMMARY: Curcuminoids, components of the rhizome of turmeric, show several beneficial biological activities, including anticarcinogenic, antioxidant, anti-inflammatory, and antitumor activities. Despite their numerous pharmaceutically important properties, the low natural abundance of curcuminoids represents a major drawback for their use as therapeutic agents. Therefore, they represent attractive targets for heterologous production and metabolic engineering. The understanding of biosynthesis of curcuminoids in turmeric made remarkable advances in the last decade, and as a result, several efforts to produce them in heterologous organisms have been reported. The artificial biosynthetic pathway (e.g., in Escherichia coli) can start with the supplementation of the amino acid tyrosine or phenylalanine or of carboxylic acids and lead to the production of several natural curcuminoids. Unnatural carboxylic acids can also be supplemented as precursors and lead to the production of unnatural compounds with possibly novel therapeutic properties. In this paper, we review the natural conversion of curcuminoids in turmeric and their production by E. coli using an artificial biosynthetic pathway. We also explore the potential of other enzymes discovered recently or already used in other similar biosynthetic pathways, such as flavonoids and stilbenoids, to increase curcuminoid yield and activity.


Assuntos
Vias Biossintéticas , Curcuma , Curcumina/análogos & derivados , Curcumina/metabolismo , Escherichia coli/metabolismo , Disponibilidade Biológica , Ácidos Carboxílicos/metabolismo , Curcuma/química , Curcuma/metabolismo , Escherichia coli/genética , Fenilalanina/metabolismo , Policetídeos/metabolismo , Tirosina/metabolismo
12.
Bioresour Technol ; 155: 28-33, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24413479

RESUMO

1,3-Propanediol (1,3-PDO) was produced from glycerol in three parallel Expanded Granular Sludge Blanket (EGSB) reactors inoculated with granular sludge (control reactor-R1), heat-treated granular sludge (R2) and disrupted granular sludge (R3) at hydraulic retention times (HRT) between 3 and 24h. Maximum 1,3-PDO yield (0.52molmol(-1)) and productivity (57gL(-1)d(-1)) were achieved in R1 at HRTs of 12 and 3h, respectively. DGGE profiling of PCR-amplified 16S rRNA gene fragments showed that variations in the HRT had a critical impact in the dominant community of microorganisms. However, no appreciable differences in the bacterial population were observed between R2 and R3 at low HRTs. Production of H2 was observed at the beginning of the operation, but no methane production was observed. This study proves the feasibility of 1,3-PDO production in EGSB reactors and represents a novel strategy to valorise glycerol generated in the biodiesel industry.


Assuntos
Bactérias Anaeróbias/metabolismo , Reatores Biológicos , Glicerol/metabolismo , Propilenoglicóis/metabolismo , Esgotos/microbiologia , Bactérias Anaeróbias/genética , Biocatálise , Biotecnologia/métodos , Eletroforese em Gel de Gradiente Desnaturante , RNA Ribossômico 16S/genética , Fatores de Tempo
13.
Nat Commun ; 4: 1715, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23591882

RESUMO

Climate models are seen by many to be unverifiable. However, near-term climate predictions up to 10 years into the future carried out recently with these models can be rigorously verified against observations. Near-term climate prediction is a new information tool for the climate adaptation and service communities, which often make decisions on near-term time scales, and for which the most basic information is unfortunately very scarce. The Fifth Coupled Model Intercomparison Project set of co-ordinated climate-model experiments includes a set of near-term predictions in which several modelling groups participated and whose forecast quality we illustrate here. We show that climate forecast systems have skill in predicting the Earth's temperature at regional scales over the past 50 years and illustrate the trustworthiness of their predictions. Most of the skill can be attributed to changes in atmospheric composition, but also partly to the initialization of the predictions.

14.
N Biotechnol ; 29(3): 395-401, 2012 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-22100432

RESUMO

In this study, a simple and efficient process to purify fructo-oligosaccharides (FOS) from a fermentative broth was proposed using a single activated charcoal column. The FOS adsorption onto the activated charcoal was modeled by a pseudo-second order model. Several volumes and concentrations of water/ethanol were studied to optimize the selective desorption of sugars from the broth mixture at 25°C. Mixtures containing 50.6% (w/w) of FOS (FOS content in the fermentative broth) were purified to 92.9% (w/w) with a FOS recovery of 74.5% (w/w). Moreover, with the proposed process, fractions with purity up to 97% (w/w) of FOS were obtained. This purification process was also found to be efficient in the desalting of the fermentative broth.


Assuntos
Carvão Vegetal/química , Meios de Cultura/química , Frutose/isolamento & purificação , Oligossacarídeos/isolamento & purificação , Saccharomycetales/crescimento & desenvolvimento , Adsorção , Frutose/biossíntese , Oligossacarídeos/biossíntese , Saccharomycetales/metabolismo
15.
J Biomed Mater Res A ; 98(4): 535-43, 2011 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-21681946

RESUMO

Depending on the final application envisaged for a given biomaterial, many surfaces must be modified before use. The material performance in a biological environment is mainly mediated by its surface properties that can be improved using suitable modification methods. The aim of this work was to coat poly(dimethyl siloxane) (PDMS) surfaces with biosurfactants (BSs) and to evaluate how these compounds affect the PDMS surface properties. BSs isolated from four probiotic strains (Lactococcus lactis, Lactobacillus paracasei, Streptococcus thermophilus A, and Streptococcus thermophilus B) were used. Bare PDMS and PDMS coated with BSs were characterized by contact angle measurements, infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM). The influence of the surface modifications on the materials blood compatibility was studied through thrombosis and hemolysis assays. The cytotoxicity of these materials was tested against rat peritoneal macrophages. AFM results demonstrated the successful coating of the surfaces. Also, by contact angle measurements, an increase of the coated surfaces hydrophilicity was seen. Furthermore, XPS analysis indicated a decrease of the silicon content at the surface, and ATR-FTIR results showed the presence of BS characteristic groups as a consequence of the modification. All the studied materials revealed no toxicity and were found to be nonhemolytic. The proposed approach for the modification of PDMS surfaces was found to be effective and opens new possibilities for the application of these surfaces in the biomedical field.


Assuntos
Dimetilpolisiloxanos/química , Probióticos/química , Tensoativos/química , Animais , Materiais Biocompatíveis/química , Materiais Revestidos Biocompatíveis/química , Teste de Materiais , Microscopia de Força Atômica , Espectroscopia Fotoeletrônica , Ratos , Ratos Wistar , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Tensoativos/isolamento & purificação
16.
Cytogenet Genome Res ; 133(1): 1-7, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21311179

RESUMO

Callicebus is a complex genus of neotropical primates thought to include 29 or more species. Currently, the genus is divided into 5 species groups: donacophilus, cupreus, moloch, torquatus and personatus. However, the phylogenetic relationships among the species are still poorly understood. This genus is karyotypically diverse and shows extensive variation in diploid number (2n = 16 to 50). To foster a better understanding of the chromosomal diversities and phylogenetic relationships among the species of Callicebus, we performed a chromosome-painting analysis on the Callicebus personatus genome using human probes, and compared the resulting hybridization map to those of previously mapped titi species. We detected 38 hybridization signals per haploid autosomal set of C. personatus. Few ancestral syntenies were conserved without rearrangement, but 4 human associations (HSA20/13, 3c/8b, 1b/1c and 21/3a/15a/14) were demonstrated to be apomorphic traits for C. persona tus. G-banding suggested that these associations are shared with C. nigrifrons and C. coimbrai (personatus group), while C. personatus is linked with C. pallescens (donacophilus group) by 2 synapomorphies: HSA10b/11 (submetacentric) and an inversion of HSA1a.


Assuntos
Genoma , Pitheciidae/genética , Animais , Coloração Cromossômica , Cromossomos Humanos , Cromossomos de Mamíferos , Feminino , Humanos , Cariotipagem
17.
Colloids Surf B Biointerfaces ; 84(1): 1-5, 2011 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-21247740

RESUMO

In the last years, researches developed with biosurfactants for application in the medical area have been revealing the promising biological activities of these biomolecules. In this work the antimicrobial and anti-adhesive properties of a biosurfactant Rufisan isolated from the yeast Candida lipolytica UCP 0988, growth in a medium supplemented with ground nut refinery residue was determined against several microorganisms. The biosurfactant was able to reduce the water surface tension from 70 to 25.3 mN/m and showed a critical micelle concentration (CMC) of 0.03%. The biosurfactant was isolated after 72 h of fermentation and was tested in concentrations varying from 0.75 to 12 mg/l. The highest antimicrobial activities were observed against Streptococcus agalactiae, Streptococcus mutans, Streptococcus mutans NS, Streptococcus mutans HG, Streptococcus sanguis 12, Streptococcus oralis J22 at a concentration superior to the biosurfactant critical micelle concentration. Moreover, the biosurfactant showed anti-adhesive activity against most of the microorganisms tested. As far as we know, this is the first compilation of data on antimicrobial and anti-adhesive activities of a biosurfactant obtained from a Candida strain against such a broad group of microorganisms. The results obtained in this work showed that the biosurfactant from C. lipolytica is a potential antimicrobial and/or anti-adhesive agent for several biomedical applications.


Assuntos
Anti-Infecciosos , Candida/metabolismo , Tensoativos , Anti-Infecciosos/metabolismo , Anti-Infecciosos/farmacologia , Candida/classificação , Escherichia/efeitos dos fármacos , Lactobacillus/efeitos dos fármacos , Streptococcus/efeitos dos fármacos , Tensoativos/metabolismo
18.
J Dairy Sci ; 94(1): 66-76, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21183018

RESUMO

The evidence that biologically active food components are key environmental factors affecting the incidence of many chronic diseases is overwhelming. However, the full extent of such components in our diet is unknown, as is our understanding of their mechanisms of action. Beyond the interaction of these food components with the gut and intestinal immune functions, whey proteins such as lactoferrin are being tested as anticancer agents. Lactoferrin is an iron-binding protein that has been reported to inhibit several types of cancer. In the present work, the effects of bovine milk lactoferrin on human breast cancer HS578T and T47D cells were studied. The cells were either untreated or treated with lactoferrin concentrations ranging from 0.125 to 125 µM. Lactoferrin decreased the cell viability of HS578T and T47D by 47 and 54%, respectively, and increased apoptosis about 2-fold for both cell lines. Proliferation rates decreased by 40.3 and 63.9% for HS578T and T47D, respectively. For the T47D line, cell migration decreased in the presence of the protein. Although the mechanisms of action are not fully known, the results gathered in this work suggest that lactoferrin interferes with some of the most important steps involved in cancer development.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Lactoferrina/farmacologia , Leite/química , Animais , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Bovinos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Feminino , Humanos
19.
Colloids Surf B Biointerfaces ; 81(1): 20-6, 2010 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-20638249

RESUMO

Poly(dimethyl siloxane) elastomer, (PDMS) is widely used as a biomaterial. However, PDMS is very hydrophobic and easily colonized by several bacteria and yeasts. Consequently, surface modification has been used to improve its wettability and reduce bacterial adhesion. The aim of this work was to modify the PDMS surface in order to improve its hydrophilicity and bacterial cell repulsion to be used as a biomaterial. Plasma was used to activate the PDMS surface and sequentially promote the attachment of a synthetic surfactant, Pluronic F-68, or a polymer, Poly(ethylene glycol) methyl methacrylate, PEGMA. Bare PDMS, PDMS argon plasma activated, PDMS coated with Pluronic F-68 and PEGMA-grafted PDMS were characterized by contact angle measurements, X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). The influence of the surface modifications on blood compatibility of the materials was evaluated by thrombosis and haemolysis assays. The cytotoxicity of these materials was tested for mouse macrophages. After modification, AFM results suggest the presence of a distinct layer at the surface and by the contact angle measures it was observed an increase of hydrophilicity. XPS analysis indicates an increase of the oxygen content at the surface as a result of the modification. All the studied materials revealed no toxicity and were found to be non-haemolytic or in some cases slightly haemolytic. Therefore, plasma was found to be an effective technique for the PDMS surface modification.


Assuntos
Materiais Biocompatíveis/química , Dimetilpolisiloxanos/química , Teste de Materiais/métodos , Animais , Materiais Biocompatíveis/farmacologia , Tecnologia Biomédica/métodos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Dimetilpolisiloxanos/farmacologia , Elastômeros/química , Elastômeros/farmacologia , Hemólise/efeitos dos fármacos , Interações Hidrofóbicas e Hidrofílicas , Macrófagos Peritoneais/citologia , Macrófagos Peritoneais/efeitos dos fármacos , Metacrilatos/química , Camundongos , Camundongos Endogâmicos BALB C , Microscopia de Força Atômica , Espectroscopia Fotoeletrônica , Poloxâmero/química , Polietilenoglicóis/química , Coelhos , Propriedades de Superfície
20.
Lett Appl Microbiol ; 50(4): 419-24, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20184670

RESUMO

AIMS: The aim of this study was to determine the antimicrobial and antiadhesive properties of a biosurfactant isolated from Lactobacillus paracasei ssp. paracasei A20 against several micro-organisms, including Gram-positive and Gram-negative bacteria, yeasts and filamentous fungi. METHODS AND RESULTS: Antimicrobial and antiadhesive activities were determined using the microdilution method in 96-well culture plates. The biosurfactant showed antimicrobial activity against all the micro-organisms assayed, and for twelve of the eighteen micro-organisms (including the pathogenic Candida albicans, Escherichia coli, Staphylococcus aureus, Staphylococcus epidermidis and Streptococcus agalactiae), the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) were achieved for biosurfactant concentrations between 25 and 50 mg ml(-1). Furthermore, the biosurfactant showed antiadhesive activity against most of the micro-organisms evaluated. CONCLUSIONS: As far as we know, this is the first compilation of data on antimicrobial and antiadhesive activities of biosurfactants obtained from lactobacilli against such a broad group of micro-organisms. Although the antiadhesive activity of biosurfactants isolated from lactic acid bacteria has been widely reported, their antimicrobial activity is quite unusual and has been described only in a few strains. SIGNIFICANCE AND IMPACT OF THE STUDY: The results obtained in this study regarding the antimicrobial and antiadhesive properties of this biosurfactant opens future prospects for its use against micro-organisms responsible for diseases and infections in the urinary, vaginal and gastrointestinal tracts, as well as in the skin, making it a suitable alternative to conventional antibiotics.


Assuntos
Anti-Infecciosos/isolamento & purificação , Lactobacillus/química , Tensoativos/química , Tensoativos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Candida albicans/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Tensoativos/isolamento & purificação
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