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1.
Chem Biodivers ; 20(2): e202200888, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36703594

RESUMO

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.


Assuntos
Fabaceae , Mananas , Mananas/análise , Mananas/química , Fabaceae/química , Polissacarídeos/química , Galactose , Sementes/química , Materiais Biocompatíveis
2.
Chemosphere ; 242: 125157, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31698213

RESUMO

Sequential anaerobic and aerobic processes have been recommended to treat textile wastewater reliably. In this work, the focus was on finding an energetically more competitive system to remove tetra-azo dye Direct Black 22 (DB22). We operated two upflow anaerobic sludge blanket (UASB) reactors (R1 and R2) in three phases (PI, PII, and PIII). R1 was operated as a conventional UASB, while R2 was microaerated in the upper part (0.18 ±â€¯0.05 mg O2. L-1), aiming to remove DB22 simultaneously with the aromatic amine byproducts. PI consisted of feeding reactors with synthetic textile wastewater (STW), PII had higher salinity in the STW, and PIII was the same as PII, plus sulfate. The results showed that color and COD removal efficiencies were similar for both reactors (67-72% for R1 and 59-78% for R2) without a substantial influence of oxygen in R2. However, microaeration played a crucial role in R2 by removing the anaerobically formed aromatic amines; during PIII, the effluent was 16 times less toxic than that of R1. The microbial community that developed in the sludge bed of both reactors was quite similar, with the core microbiome represented by Trichococcus, Syntrophus and Methanosaeta genera. The increase in salinity in PII and PIII promoted a shift in the microbial community, excluding salty-sensitive genera from the core microbiome. The putative genera Brevundimonas and Ornatilinea were associated to aromatic amine microaerobic removal. Therefore, there is a potential application of a compact microaerated anaerobic system for textile wastewater treatment.


Assuntos
Reatores Biológicos/normas , Microbiota , Naftalenos/isolamento & purificação , Têxteis , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Purificação da Água/métodos , Aerobiose , Anaerobiose , Compostos Azo , Esgotos/microbiologia , Sulfatos , Águas Residuárias/microbiologia
3.
Water Sci Technol ; 76(11-12): 3319-3327, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29236011

RESUMO

In the present study, we evaluate the behavior of real textile wastewater treatment using a system composed of two sequential pilot-scale reactors (anaerobic followed by aerobic) during 622 days. The work focused on the competition between color and sulfate removal processes, when the hydraulic retention time (HRT) was increased in the anaerobic/aerobic reactors from 16/12 hours in phase I (PI) to 4/3 days in phase II (PII). The organic matter was successfully removed in both phases through the system, and the highest efficiency (75%) was achieved in PII. The increase in the HRT did not improve azo dye degradation under anaerobic conditions. Instead, it favored sulfate reduction, which removal efficiency increased from 26% in PI to 75% in PII. Aromatic amines were detected in the anaerobic reactor effluent and removed in the aerobic reactor.


Assuntos
Compostos Azo/metabolismo , Reatores Biológicos , Corantes/metabolismo , Sulfatos/metabolismo , Indústria Têxtil , Águas Residuárias/química , Aerobiose , Anaerobiose , Compostos Azo/química , Corantes/química , Resíduos Industriais , Sulfatos/química , Óxidos de Enxofre , Eliminação de Resíduos Líquidos
4.
Genet Mol Res ; 16(1)2017 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-28252168

RESUMO

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.


Assuntos
Cistationina beta-Sintase/genética , Epistasia Genética , Predisposição Genética para Doença/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Polimorfismo de Nucleotídeo Único , Trombose/genética , Adolescente , Adulto , Brasil , Estudos Transversais , Feminino , Ácido Fólico/sangue , Frequência do Gene , Genótipo , Heterozigoto , Homocisteína/sangue , Homozigoto , Humanos , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Trombofilia/sangue , Trombofilia/genética , Trombose/sangue , Vitamina B 12/sangue , Adulto Jovem
5.
Rev. bras. plantas med ; 18(1): 19-26, jan.-mar. 2016. tab, graf
Artigo em Português | LILACS | ID: lil-780042

RESUMO

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.


Assuntos
Toxicidade , Óleos Voláteis/química , Química , Aedes/classificação , Myrtaceae/química , Artemia/classificação , Larvicidas
6.
Bioresour Technol ; 163: 364-9, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24813565

RESUMO

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.


Assuntos
Cor , Compostos Orgânicos/isolamento & purificação , Sulfatos/isolamento & purificação , Indústria Têxtil , Águas Residuárias , Aerobiose , Anaerobiose , Análise da Demanda Biológica de Oxigênio , Reatores Biológicos , Ácidos Graxos Voláteis/síntese química , Filtração/métodos , Esgotos
7.
Rev. bras. plantas med ; 16(1): 135-167, 2014. tab
Artigo em Português | LILACS | ID: lil-703734

RESUMO

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.


Assuntos
Saúde Bucal/classificação , Odontologia/classificação , Plantas Medicinais/metabolismo , Extratos Vegetais , Noxas
8.
Rev. bras. farmacogn ; 13(supl.1): 27-30, 2003. ilus
Artigo em Português | LILACS | ID: lil-526237

RESUMO

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.

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