Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 6 de 6
Filter
Add more filters











Publication year range
1.
Chem Biodivers ; 20(2): e202200888, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36703594

ABSTRACT

Aiming of self-sustainable production, the search for biodegradable and biocompatible materials has brought with it the need to know the physicochemical and dielectric characteristics of polysaccharide-based composite structures, which can be used as important and promising raw materials for biotechnology and electronic industries. Galactomannans are polysaccharides, extracted from seeds and microbiological sources, consisting of mannose and galactose. In this context, this work aimed to extract, purify and characterize by XRD, FTIR and impedance spectroscopy galactomannan obtained from seeds of Adenanthera pavonina L. The purification process was made with ethyl alcohol at concentrations of 70, 80 and 90 %. Polymeric films were prepared by solvent slow evaporation at low temperatures. XRD measurements revealed that Galactomannan from Adenanthera pavonina L., after purification, has a semi-crystalline structure due to the identification of two peaks the first between 5.849° and 6.118° and the second between 20.011° and 20.247°. FTIR spectra showed the functional groups associated with monosaccharides of the galactomannan from Adenanthera pavonina L. seeds, as well as the typical polysaccharide bands and peaks, confirmed by literature data. The impedance results give an increment on the state-of-the-art of this biomaterial by showing the existence of dielectric relaxations, independent of the degree of purification, using the dielectric modulus formalism. The permittivity analysis reveals the presence of water in the structure of the film, whose dipoles contribute to the relatively high value of the dielectric constant. From the results obtained, it can be concluded that purified galactomannan has the potential for possible applications in the electronics industry as a green and eco-friendly dielectric material.


Subject(s)
Fabaceae , Mannans , Mannans/analysis , Mannans/chemistry , Fabaceae/chemistry , Polysaccharides/chemistry , Galactose , Seeds/chemistry , Biocompatible Materials
2.
Genet Mol Res ; 16(1)2017 Feb 23.
Article in English | MEDLINE | ID: mdl-28252168

ABSTRACT

High plasma homocysteine (Hcy) ​​levels may be responsible for vaso-occlusive episodes and may have acquired and/or genetic causes. This cross-sectional study aimed to investigate the role of methylenetetrahydrofolate reductase (MTHFR; C677T; A1298C) and cystathionine-ß-synthase (CBS; T833C/844ins68, G919A) polymorphisms in serum levels of folic acid, vitamin B12 and Hcy, and to verify a possible association between these polymorphisms and the clinical variability. Blood samples of Brazilian patients with a diagnosis of thrombosis were submitted to genotyping by PCR-based methods and serum dosages of folic acid, vitamin B12 and Hcy. Except for the CBS G919A polymorphism, all other genetic markers were in Hardy-Weinberg equilibrium. An increased risk for venous thrombosis was found for the MTHFR 1298CC carriers (OR = 1.688; 95%CI = 0.839-3.398, P = 0.018) and those homozygously mutant for the CBS haplotype 844ins68/T833C (OR = 2.488; 95%CI = 0.501-12.363, P = 0.031), while heterozygous for this CBS haplotype showed an increased risk for higher Hcy levels (OR = 5.900; 95%CI = 1.003-34.691, P = 0.030). Significant interactions were observed among the MTHFR C677T, MTHFR A1298C and CBS haplotype 844ins68/T833C polymorphisms in the results for Hcy levels (P = 0.000), where heterozygous had higher values. Interactions among these polymorphisms can affect serum Hcy levels, where multiple heterozygosis could be a risk factor for vaso-occlusive episodes.


Subject(s)
Cystathionine beta-Synthase/genetics , Epistasis, Genetic , Genetic Predisposition to Disease/genetics , Methylenetetrahydrofolate Reductase (NADPH2)/genetics , Polymorphism, Single Nucleotide , Thrombosis/genetics , Adolescent , Adult , Brazil , Cross-Sectional Studies , Female , Folic Acid/blood , Gene Frequency , Genotype , Heterozygote , Homocysteine/blood , Homozygote , Humans , Linkage Disequilibrium , Male , Middle Aged , Risk Factors , Thrombophilia/blood , Thrombophilia/genetics , Thrombosis/blood , Vitamin B 12/blood , Young Adult
3.
Rev. bras. plantas med ; Rev. bras. plantas med;18(1): 19-26, jan.-mar. 2016. tab, graf
Article in Portuguese | LILACS | ID: lil-780042

ABSTRACT

RESUMO A dengue está entre as doenças virais de propagação vetorial mais importante no mundo, causando sérios impactos de morbidade e mortalidade. Desta forma, o presente trabalho teve como objetivo analisar a composição química e a toxicidade do óleo essencial de Myrcia sylvatica (G. Mey) D.C. frente Aedes aegypti e Artemia salina. Folhas de M. sylvatica foram coletadas no Parque Nacional da Chapada das Mesas, no município de Carolina (MA) no mês de fevereiro de 2012. O óleo foi obtido por hidrodestilação e sua composição química foi determinada por cromatografia gasosa acoplada à espectrometria de massa (CG/EM). O bioensaio frente Artemia salina e às larvas de 3° estádio de Aedes aegypti foram realizados em diferentes concentrações. Os dados de mortalidade foram avaliados por regressão linear para determinar os valores de CL50. Obteve-se 0,5% de rendimento, sendo o (E)-cariofileno o constituinte majoritário. O óleo essencial apresentou uma CL50 = 79,44 µg/mL frente A. salina, sendo considerado altamente tóxico. No entanto, este óleo não demonstrou efeito sobre as larvas de A. aegypti. Considerando que o teste de Artemia salina tem correlação com atividades biológicas de grande interesse terapêutico como antitumoral, o óleo essencial das folhas de M. sylvatica demonstrou potencial para desenvolvimento de produtos farmacêuticos.


ABSTRACT Dengue is among the most important viral diseases of vector spread in the world, causing serious impacts of morbidity and mortality. Thus, this study aimed to analyze the chemical composition and toxicity of the Myrcia sylvatica (G. Mey.) DC essential oil against Aedes aegypti and Artemia salina Leach. Leaves of M. sylvatica. were collected in the Tables Chapada National Park, in the municipality of Carolina (MA) in february 2012. The oil was obtained by hydrodistillation and their chemical composition was determined by GC / MS. The bioassay front and Artemia salina larvae of the 3° stage of Aedes aegypti were performed at different concentrations. Mortality data were evaluated by linear regression to determine the LC50. Was obtained 0.5% yield values, and (E) -caryophyllene the major constituent. The essential oil showed a LC50 = 79.44 mg / mL front A. saline and is considered highly toxic. However, this oil showed no effect on larvae of A. aegypti. Whereas the brine shrimp test has regard to several biological activities, as antitumoral property, the essential oil from the leaves of M. sylvatica demonstrated potential for development of medicines.


Subject(s)
Toxicity , Oils, Volatile/chemistry , Chemistry , Aedes/classification , Myrtaceae/chemistry , Artemia/classification , Larvicides
4.
Bioresour Technol ; 163: 364-9, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24813565

ABSTRACT

An upflow anaerobic sludge blanket (UASB)-submerged aerated biofilter (SAB) system was evaluated to remove color and chemical oxygen demand (COD) from real textile effluent. The system was operated for 335 days in three phases (P-1, P-2, P-3) with total hydraulic retention time varying from 21 h to 14 h. The results showed that high sulfate levels (>300 mg SO4(2-)/L) impaired the dye reduction. The best color removal efficiencies of 30% and 96% for the UASB and the reactor system, respectively, were obtained in P-1; the SAB higher efficiency was associated with adsorption. The best COD removal efficiency of 71% for the reactor system was obtained in P-2. Precipitation of some material composed mostly of sulfur (98%) and some metals occurred in the UASB. However, the precipitated sulfur was again oxidized in the SAB. The system also showed an effective toxicity reduction in tests (Daphnia magna) with the treated effluent.


Subject(s)
Color , Organic Chemicals/isolation & purification , Sulfates/isolation & purification , Textile Industry , Wastewater , Aerobiosis , Anaerobiosis , Biological Oxygen Demand Analysis , Bioreactors , Fatty Acids, Volatile/chemical synthesis , Filtration/methods , Sewage
5.
Rev. bras. plantas med ; Rev. bras. plantas med;16(1): 135-167, 2014. tab
Article in Portuguese | LILACS | ID: lil-703734

ABSTRACT

Produtos derivados de plantas podem representar estratégia promissora na odontologia. Desse modo, o objetivo deste trabalho foi levantar na literatura os estudos sobre o uso popular de plantas em afecções orais, bem como os estudos de avaliação da atividade antimicrobiana in vitro de extratos vegetais e compostos isolados sobre patógenos orais, no período de 1996 a 2011. Quarenta e sete famílias botânicas foram referidas, com maior número de citações para Anacardiaceae, sendo Anacardium occidentale L., a espécie mais citada. O levantamento sobre estudos de avaliação antimicrobiana relacionou extratos de sessenta e seis espécies vegetais pertencentes a trinta e oito famílias botânicas, destacando-se Anacardiaceae, com pesquisas realizadas de forma predominante com as folhas, investigadas pelo método de difusão em ágar. Cinquenta e oito substâncias isoladas de plantas foram avaliadas, demonstrando que Terminalia chebula Retz (Combretaceae) representa a espécie vegetal com atividade antimicrobiana in vitro mais significativa, apresentando halo de inibição de 32,97 mm contra Staphylococcus aureus, microrganismo encontrado em infecções orais; enquanto ácido tetra iso-alfa isolada de Humulus lupulus L. (Canabinaceae) apresentou maior halo de inibição para Streptococcus mutans (26,0 mm). Os resultados apresentados devem estimular o desenvolvimento dos estudos de validação na garantia do uso seguro e eficaz de espécies vegetais em odontologia.


Products derived from plants may represent a promising strategy in dentistry. Thus, the objective of this paper is to review studies of the popular use of plants in oral diseases, as well as studies evaluating the in vitro antimicrobial activity of plant extracts and isolated compounds in oral pathogens from 1996 to 2011. Forty-seven botanical families were mentioned, with the highest number of referencesfor Anacardiaceae, and Anacardium occidentale L. was the most mentioned specie. The review of antimicrobial activity studies relatedextracts from sixty-six plant species belonging to thirty-eight botanical families, especially Anacardiaceae, being predominant tests with leaves, investigated by the agar diffusion method. Fifty-eight compounds isolated from plants have been evaluated, showing that Terminalia chebula Retz (Combretaceae) represents the plant species with more meaningful in vitro antimicrobial activity, with inhibition zone of 32.97 mm against Staphylococcus aureus, microorganism found in oral infections, while tetra iso-alpha acid isolated from Humulus lupulus L. (Canabinaceae) showed greater inhibition zone for Streptococcus mutans (26.0 mm). The presented results should encourage the development of validation studies, ensuring the safe and effective use of plant species in dentistry.


Subject(s)
Oral Health/classification , Dentistry/classification , Plants, Medicinal/metabolism , Plant Extracts , Noxae
6.
Rev. bras. farmacogn ; 13(supl.1): 27-30, 2003. ilus
Article in Portuguese | LILACS | ID: lil-526237

ABSTRACT

Análise da qualidade de plantas comercializadas para fins terapêuticos em mercados públicos de São Luís/MA. Realizou-se pesquisa de elementos estranhos, avaliação das características macroscópicas, determinação do teor de umidade e pesquisa de contaminantes microbiológicos, comprovandose a má qualidade do material vegetal disponibilizado à população maranhense, expondo ao risco real de aquisição e utilização de produto impróprio para consumo.


Qualitative analysis of plants commercialized for medical purposes in public markets in São Luís/MA. It's made a research on strange materials, evaluation of macroscopic characteristics, determination of humidity level and research on microbiological contamination, this way proving the bad quality of vegetable material available for the population in Maranhão state.

SELECTION OF CITATIONS
SEARCH DETAIL