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Em busca da sustentabilidade: células solares sensibilizadas por extratos naturais; Toward sustainability: solar cells sensitized by natural extracts

PATROCÍNIO, Antonio Otávio T.; MURAKAMI IHA, Neyde Y.
Fonte: Sociedade Brasileira de Química Publicador: Sociedade Brasileira de Química
Tipo: Artigo de Revista Científica
POR
Relevância na Pesquisa
56.04%
The present work reports the use of anthocyanins extracted from mulberry (Morus Alba L.), raspberry (Rubus Idaeus L.) and blueberry (Vaccinium myrtillus L.) as sensitizers in dye-sensitized solar cells. The conversion efficiency of these devices is dependent on the extracts employed and can be rationalized in terms of their composition and spectral properties. Solar cells sensitized by the mulberry extract showed the highest efficiency among the fruits investigated. Moreover, a 16 cm² active area solar cell with the mulberry extract has presented fair good efficiency of conversion for natural dye-based solar cells, besides stability over twenty weeks, showing perspectives for developing these low cost devices with a commercial viability.

Effects of natural antioxidants on the lipid profile of electron beam-irradiated beef burgers

TRINDADE, Reginaldo Almeida da; MANCINI-FILHO, Jorge; VILLAVICENCIO, Anna Lucia Casanas Haasis
Fonte: WILEY-V C H VERLAG GMBH Publicador: WILEY-V C H VERLAG GMBH
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
46.07%
The purpose of this study was to assess the efficacy of rosemary and oregano extracts in avoiding oxidative changes in beef burgers, and to evaluate the fatty acid profile of these products after electron beam exposition. Extracts, individually or in combination, were added to beef burgers and compared to synthetic antioxidants commonly used in food (butylated hydroxytoluene, butylated hydroxyanisole). The ground beef were submitted to electron beam irradiation at doses of 0, 3.5 and 7 kGy, and stored for 90 days. At regular time intervals, lipid oxidation and fatty acid composition were evaluated through measurement of thiobarbituric acid-reactive substances (TBARS) and gas chromatography, respectively. The results indicate that, although the irradiation process triggers an increase in the lipid oxidation ratio expressed by TBARS values, great changes in the fatty acid profiles were not observed; instead, they continued to present characteristics very similar to that of non-irradiated beef. Thus, as irradiation doses of up to 7 kGy for frozen meat can make foods safe from foodborne pathogens, natural antioxidants derived from spices are able to reduce and avoid lipid changes that may cause a deterioration of the sensory quality of these foods...

Evaluation of the antioxidant activity as an additional parameter to attain the functional quality of natural extracts

MARQUELE-OLIVEIRA, Franciane; FONSECA, Yris M.; GEORGETTI, Sandra R.; VICENTINI, Fabiana T. M. C.; BRONZATI, Viviane; FONSECA, Maria J. V.
Fonte: COLEGIO FARMACEUTICOS PROVINCIA DE BUENOS AIRES Publicador: COLEGIO FARMACEUTICOS PROVINCIA DE BUENOS AIRES
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
66.2%
Due to differences in the functional quality of natural extracts, we have also faced differences in their effectiveness. So, it was intended to assess the antioxidant activity of natural extracts in order to attain their functional quality. It was observed that all the extracts (brown and green propolis, Ginkgo biloba and Isoflavin Beta (R)) and the standard used (quercetin) showed antioxidant activity in a dose-dependent manner with IC50 values ranging from 0.21 to 155.28 mu g mL(-1) (inhibition of lipid peroxidation and scavenging of the DPPH center dot assays). We observed a high correlation (r(2)= 0.9913) among the antioxidant methods; on the other hand, the antioxidant activity was not related to the polyphenol and flavonoid content. As the DPPH center dot assay is a fast method, presents low costs and even has a high correlation with other antioxidant methods, it could be applied as an additional parameter in the quality control of natural extracts.

Triagem da atividade antioxidante e anticolinesterásica de extratos naturais: seleção e estudo químico biomonitorado de Streptomyces sp. e de Psychotria carthagenensis; Screening of antioxidant and anticholinesterase activity of natural extracts: selection and bioassay-guided chemical study of Streptomyces sp. and Psychotria carthagenensis

Lima, Letícia Bazeia
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 29/09/2011 PT
Relevância na Pesquisa
56.14%
Esse trabalho descreve o estudo monitorado de extratos de origem microbiológica e vegetal. Com o objetivo de identificar compostos com atividade antioxidante e/ou inibidores da enzima acetilcolinesterase em extratos de origem microbiológica e vegetal do cerrado brasileiro, uma triagem de atividade foi realizada utilizando ensaios simples e rápidos. Nessa triagem dois extratos promissores foram selecionados para os estudos de identificação dos compostos responsáveis pela atividade inicial. O trabalho de purificação foi iniciado com a fração em acetato de etila do extrato etanólico da actinobactéria-36 (50PL), Streptomyces sp., fermentado em meio de canjica amarela que apresentou atividade nos dois ensaios realizados. As atividades antioxidante e anticolinesterásica são relatadas pela primeira vez para essa actinobactéria. Nesse estudo foram identificados dois compostos, o éster metílico do ácido cis-6, cis-8 octadecadienóico e o tetradecanal. Da espécie Psychotria carthagenensis, uma planta da família Rubiaceae, foram objeto de estudo as frações hexânica e acetato de etila oriundas do extrato etanólico das folhas, o extrato hexânico das folhas e o extrato etanólico dos caules. A espécie P. cartahgenensis foi investigada quanto à presença de alcalóides uma vez que é utilizada juntamente com as espécies Psychotria viridis e Banisteriopsis caapi no preparo de uma bebida alucinógena conhecida como ayahuasca. A partir dos extratos etanólicos das sementes...

Uso de extratos antioxidantes naturais obtidos de ervas aromáticas na elaboração de produtos a base de carne ovina; Use of natural antioxidant extracts obtained from aromatic herbs in developing products based on sheep meat

Fernandes, Rafaella de Paula Paseto
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 09/06/2015 PT
Relevância na Pesquisa
36.22%
Atualmente, existem inúmeros questionamentos quanto aos prováveis efeitos mutagênicos e carcinogênicos dos antioxidantes sintéticos no organismo, e devido a isto, hoje em dia estudos tendem a promover a substituição destes compostos por naturais com o intuito de maior segurança do alimento, sendo que estes apresentam benefícios potenciais à saúde. O objetivo deste estudo foi o uso de antioxidantes naturais obtidos de ervas e especiarias no desenvolvimento de produtos cárneos a base de carne ovina buscando suas propriedades antioxidantes e sensoriais, bem como agregar valor ao produto final, desenvolvido com carne de baixo valor comercial. O apelo de saudabilidade dos produtos foi obtido pela adição de extratos antioxidantes naturais à base de ervas aromáticas selecionadas em função de seu poder antioxidante e harmonização de sabores com a carne ovina. Um primeiro experimento (Capítulo 2) consistiu na avaliação da capacidade antioxidante dos extratos de 13 espécies vegetais, sendo selecionados por Cluster analysis em relação a três métodos colorimétricos e sensorialmente após a adição em produto cárneo. O extrato selecionado foi avaliado quanto a acidez, à identificação e quantificação de compostos fenólicos e utilizado para a elaboração de hambúrguer congelado (Capítulo 3) e linguiça cozida (Capítulo 4)...

Antioxidant activity of basil and oregano extracts added to soybean oil for accelerated storage test

Pitaro, S.; Fiorani, L.; Jorge, N.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 485-490
ENG
Relevância na Pesquisa
45.96%
The objective of this research was to evaluate the antioxidant activity of extract of basil and oregano, and its synergistic effect when added to soybean oil and subjected to accelerated storage test. Extracts of basil, oregano and mixtures of both were applied to soybean oil at a concentration of 2.000mg/kg, then the extracts were heated in an oven at 60C for a period of 10 days. Samples were taken every 2 days and analyzed for concentrations of peroxides and conjugated dienes. Synthetic antioxidant tert-butylhydroquinone (TBHQ) at a concentration of 50mg/kg and soybean oil free antioxidant (control) subject to the same conditions were used as benchmarks. The results showed that the antioxidant effect decreases according to oil heating for all treatments. However, the synthetic antioxidant showed superior protection to the soybean oil during the formation of primary oxidation compounds, followed by the natural extracts, which showed no synergism. © 2012 Wiley Periodicals, Inc.

Efeitos in vitro de extratos naturais sobre Enterococcus faecalis, Staphylococcus aureus, Escherichia coli e endotoxinas em canais radiculares

Brito, Emanuele Gonçalves
Fonte: Universidade Estadual Paulista (UNESP) Publicador: Universidade Estadual Paulista (UNESP)
Tipo: Dissertação de Mestrado Formato: 130 f. : il. il.
POR
Relevância na Pesquisa
46.03%
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Pós-graduação em Biopatologia Bucal - ICT; A proposta deste trabalho foi avaliar a efetividade de extratos naturais, como soluções irrigadoras, sobre E. faecalis, S. aureus, E. coli, e endotoxinas (LPS) em canais radiculares. Foi avaliado também o efeito citotóxico do conteúdo do canal, após os tratamentos, pela produção de TNF-α e IL-1β em cultura de macrófagos. Foram utilizados 84 dentes unirradiculados, contaminados com associação dos três microrganismos por 28 dias. Após, foram divididos em 7 grupos (n=12), de acordo com o irrigante utilizado: G1) solução fisiológica (controle); G2) solução de clorexidina 2%; G3) extrato glicólico de própolis 12%; G4) extrato glicólico de alcaçuz 20%; G5) extrato glicólico de barbatimão 20%; G6) extrato glicólico de romã 20%; G7) extrato glicólico de cavalinha 20%. Foram realizadas 2 coletas do conteúdo do canal radicular: imediatamente após a instrumentação e após 7 dias da instrumentação. Para todas as coletas, foi realizada avaliação da atividade antimicrobiana pela contagem de UFC/mL em meios de cultura seletivos, verificação da neutralização de endotoxinas pelo teste cinético cromogênico do lisado de amebócitos de Limulus (LAL) e avaliação dos efeitos citotóxicos do conteúdo do canal pela produção de IL-1 e TNF-α por macrófagos. Os resultados foram analisados estatisticamente (ANOVA e teste de Tukey...

Secagem convectiva de papel reciclado com incorporação de corantes naturais; Convective drying of recycled paper with incorporation of natural dyes

Néstor David López González
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 16/08/2012 PT
Relevância na Pesquisa
46.02%
O papel está presente em muitas das atividades do cotidiano que vão desde usos sanitários, passando pelas embalagens até fins educativos. Este material que teve sua origem há quase 2000 anos, continua sua evolução na procura de alternativas limpas para seu reaproveitamento. Novos processos de reciclagem, secagem e a incorporação de materiais alternativos para melhorar as propriedades do papel fazem desta área de pesquisa a base para a criação de novas tecnologias e produtos com apelo ambiental. Neste contexto, este trabalho teve como objetivo a avaliação da reutilização de papel de escritório na forma de papel cartão com adição de extratos corantes naturais Carmim de cochonilha, Cúrcuma e Urucum, implementando um processo de destintagem dos papéis a serem reciclados e secando o papel em um secador convectivo em escala laboratorial para obter papel cartão artesanal colorido. Para isto, foi determinada uma formulação para cada uma das três polpas a serem tingidas com os corantes naturais e construídas as curvas de secagem para diferentes condições de secagem. Efetuou-se uma análise comparativa da qualidade dos papéis obtidos em diferentes condições de secagem e avaliou-se a degradação da cor dos papéis obtidos sob diferentes condições de iluminação. O estudo da secagem mostrou que as polpas fabricadas com cada um dos três corantes apresentaram processos de secagem equivalentes apesar de ter formulações diferentes. Além disso...

Utilização de extratos comerciais derivados de plantas em produtos cárneos : avaliação da atividade antioxidante; Plant-derived commercial extracts on meat products : study on the antioxidant activity

Camila de Souza Paglarini
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 06/04/2015 PT
Relevância na Pesquisa
46.27%
Os produtos cárneos são muito susceptíveis à oxidação lipídica, uma das principais reações de deterioração e a causa principal de sabor e odor desagradáveis, redução do valor nutricional e da vida útil, além da formação de compostos tóxicos. O consumo excessivo de produtos cárneos está relacionado com o aumento do risco de algumas doenças, tais como doenças cardiovasculares, câncer, hipertensão e obesidade e assim pesquisas vem sendo desenvolvidas para elaboração de produtos mais saudáveis, dentre os quais destacam-se aqueles com redução de aditivos sintéticos. Neste contexto, o objetivo do presente estudo foi avaliar a atividade antioxidante de extratos comerciais derivados de plantas em matéria-prima cárnea (carne de frango mecanicamente separada - CFMS) e em produto cárneo reestruturado elaborado com diferentes matérias-primas (carne bovina, suína, de frango e CFMS). As concentrações dos extratos naturais foram de 0,125, 0,25, 0,5 e 1,0%, m/m. Os extratos foram caracterizados quanto ao teor de compostos fenólicos, flavonóides totais, atividade antioxidante ORAC, DPPH e ABTS. A oxidação lipídica foi avaliada pela análise de substâncias reativas ao ácido tiobarbitúrico - TBARS. A matéria-prima cárnea foi avaliada crua em ambiente refrigerado (4 °C) nos dias 0...

Natural extracts from wild flowers used in Portuguese folk medicine like a new antifungal agents against Candida species

Alves, Carlos; Ferreira, Isabel C. F. R.; Barros, Lillian; Silva, Sónia Carina; Oliveira, Rosário; Henriques, Mariana
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Conferência ou Objeto de Conferência
Publicado em //2012 ENG
Relevância na Pesquisa
46.16%
The prevalence of opportunistic fungal infections has been increasing dramatically over the recent decades mainly due to the boom of the AIDS epidemic, increasing number of immunocompromised patients and the commonly use of indwelling medical devices. Although Candida albicans has been regarded as the most common causative agent of fungal infection in humans, nowadays other non-Candida albicans Candida (NCAC) species such as Candida glabrata, Candida tropicalis and Candida parapsilosis, are emerging as significant nosocomial pathogens and with high level of resistance to certain antifungal drugs. So, in the last years the interest in natural compounds has raised, specifically some phenolic extracts which have been known in folk medicine as antimicrobial agents. Thus, this work aimed to perform a screening of the antifungal potential of phenolic extracts of Castanea sativa, Filipendula ulmaria and Rosa micrantha flowers from Northeastern Portugal, against Candida species. The extracts were exhaustively characterized by HPLC-DAD-ESI/MS. Hydrolysable tannins were the main group of phenolic compounds in C. sativa and F. ulmaria samples, while flavonoids including procyanidins were the most abundant group in R. micrantha (6090 ± 253 mg/Kg). The minimal inhibitory concentration (MIC) was determined according with the guidelines in National Committee for Clinical Laboratory Standards (NCCLS...

Antifungal activity of natural extracts from Northeastern Portuguese flowers against Candida biofilms

Alves, Carlos; Ferreira, Isabel C. F. R.; Barros, Lillian; Silva, Sónia Carina; Oliveira, Rosário; Henriques, Mariana
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Conferência ou Objeto de Conferência
Publicado em //2012 ENG
Relevância na Pesquisa
66.21%
In healthy individuals, many species of Candida are endogenous commensals of the gastrointestinal and urogenital tracts. However, the prevalence of opportunistic fungal infections (candidosis) has been increasing dramatically over the recent decades and this is particularly evident in immunocompromised individuals. The importance of candidosis is the potential synergistic effect on virulence and subsequent difficulties encountered in treatment. Moreover, a major virulence factor of Candida is its ability to adapt to a variety of different habitats and the consequent formation of surface attached microbial communities known as biofilms. The resistance of Candida biofilms to antifungal agents was first demonstrated by Hawser et al., 1995. Although most episodes of candidosis are attributed to C. albicans, nowadays non-Candida albicans Candida (NCAC), such as C. glabrata, C. tropicalis and C. parapsilosis have emerged as important pathogens and tend to be inherently less susceptible to commonly used antifungal agents. So, in the last years the interest in natural compounds has increased, specifically some phenolic extracts which have been known in folk medicine as antimicrobial agents. Thus, this work aimed to preform a screening of the antifungal potential of phenolic extracts from Castanea sativa...

Evaluation of chemotherapeutic potential of natural extracts using 3D models of colon cancer

Silva, Inês Alexandra Marreiros
Fonte: Faculdade de Ciências e Tecnologia Publicador: Faculdade de Ciências e Tecnologia
Tipo: Dissertação de Mestrado
Publicado em //2013 ENG
Relevância na Pesquisa
66.24%
Dissertation to obtain master degree in Biotechnology; Recently there is a growing interest in cancer treatment through the use of natural compounds. In particular, phenolic compounds and monoterpenes found in fruits and vegetables are very attractive in the prevention and chemotherapy of various types of cancer. However, many promising compounds previously tested in in vitro cell models fail to demonstrate activity when evaluated in vivo. Therefore, there is an emerging need to develop more robust and reliable cellular models for pre-clinical evaluation of new chemotherapeutic agents. The main goal of this thesis was the evaluation of the chemotherapeutic potential of natural extracts, rich in bioactive compounds, using 3D models of colon cancer. For this purpose, a 3D model of human colorectal cancer cell line HT29 was developed. By culturing HT29 cells in a stirred culture system, it was possible to obtain 3D cellular spheroids with different size diameter during culture time. It was verified phenotypic changes within the spheroid along culture, such as formation of apoptotic core and altered expression of stem and epithelial markers in different spheroid areas, which are typical features of tumor progression. After an initial screening of the antiproliferative potential of 14 natural extracts performed in a 2D model of HT29 cells...

Evaluation of neuroprotective effects of natural extracts obtained from portuguese agro-food residues

Ramos, Rita João Rosado Serranito
Fonte: Universidade Nova de Lisboa Publicador: Universidade Nova de Lisboa
Tipo: Dissertação de Mestrado
Publicado em /09/2012 ENG
Relevância na Pesquisa
56.12%
Countries are currently faced with problems derived from changes in lifespan and an increase in lifestyle-related diseases. Neurodegenerative disorders such Parkinson’s (PD) and Alzheimer’s (AD) diseases are an increasing problem in aged societies. Data from World Alzheimer Report 2011 indicate that 36 million people worldwide are living with dementia. Oxidative stress has been associated with the development of AD and PD. Therefore there is interest to search for effective compounds or therapies to combat the oxidative damage in these diseases. Current evidence strongly supports a contribution of phenolic compounds present in fruits and vegetables to the prevention of neurodegenerative diseases such AD and PD. The industrial processing of a wide variety of fruits results in the accumulation of by-products without commercial value. Opuntia ficus-indica (cactus pear) is consumed fresh and processed like in juice. Prunnus avium (sweet cherry) is consumed fresh but the organoleptics characteristics of the fruits leads to the smaller and ragged fruits have no commercial value. Fruit extracts of both species has described to be rich in phenolic compounds and to have high antioxidant activities due to its composition. The aim of this work was assessing the efficacy of O. ficus-indica and P. avium by-products extracts obtained with conventional solvent extraction and pressurized liquid extraction in a neurodegeneration cell model. All extracts have protected neuroblastoma cells from H2O2-induced death at low...

Antimicrobial Activity of Toothpastes Containing Natural Extracts, Chlorhexidine or Triclosan

Rossi,Andiara De; Ferreira,Danielly Cunha Araújo; Silva,Raquel Assed Bezerra da; Queiroz,Alexandra Mussolino de; Silva,Léa Assed Bezerra da; Nelson-Filho,Paulo
Fonte: Fundação Odontológica de Ribeirão Preto Publicador: Fundação Odontológica de Ribeirão Preto
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2014 EN
Relevância na Pesquisa
66.21%
Abstract: The objective of this in vitro study was to evaluate the antimicrobial effect of toothpastes containing natural extracts, chlorhexidine or triclosan. The effectiveness of toothpastes containing natural extracts (Parodontax(r)), 0.12% chlorhexidine (Cariax(r)), 0.3% triclosan (Sanogil(r)) or fluoride (Sorriso(r), control) was evaluated against yeasts, Gram-positive and Gram-negative bacteria using the disk diffusion method. Water was used as a control. Disks impregnated with the toothpastes were placed in Petri dishes containing culture media inoculated with 23 indicative microorganisms by the pour plate method. After incubation, the inhibition growth halos were measured and statistical analyses (α=0.05) were performed. The results indicated that all formulations, except for conventional toothpaste (Sorriso(r)), showed antimicrobial activity against Gram-positive bacteria and yeasts. The toothpaste containing natural extracts (Parodontax(r)) was the only product able to inhibit the growth of Pseudomonas aeruginosa. The toothpastes containing chlorhexidine, triclosan or natural extracts presented antimicrobial activity against Gram-positive bacteria and yeasts.

In vitro antimicrobial activity of auxiliary chemical substances and natural extracts on Candida albicans and Enterococcus faecalis in root canals

Valera,Marcia Carneiro; Maekawa,Lilian Eiko; Oliveira,Luciane Dias de; Jorge,Antonio Olavo Cardoso; Shygei,Erika; Carvalho,Claudio Antonio Talge
Fonte: Faculdade De Odontologia De Bauru - USP Publicador: Faculdade De Odontologia De Bauru - USP
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/2013 EN
Relevância na Pesquisa
45.91%
Objective: The aim of this study was to evaluate the antimicrobial activity of auxiliary chemical substances and natural extracts on Candida albicans and Enterococcus faecalis inoculated in root canals. Material and Methods: Seventy-two human tooth roots were contaminated with C. albicans and E. faecalis for 21 days. The groups were divided according to the auxiliary chemical substance into: G1) 2.5% sodium hypochlorite (NaOCl), G2) 2% chlorhexidine gel (CHX), G3) castor oil, G4) glycolic Aloe vera extract, G5) glycolic ginger extract, and G6) sterile saline (control). The samples of the root canal were collected at different intervals: confirmation collection, at 21 days after contamination; 1st collection, after instrumentation; and 2nd collection, seven days after instrumentation. Microbiological samples were grown in culture medium and incubated at 37°C for 48 hours. Results: The results were submitted to the Kruskal-Wallis and Dunn (5%) statistical tests. NaOCl and CHX completely eliminated the microorganisms of the root canals. Castor oil and ginger significantly reduced the number of CFU of the tested bacteria. Reduction of CFU/mL at the 1st and 2nd collections for groups G1, G2, G3 and G4 was greater in comparison to groups G5 and G6. Conclusion: It was concluded that 2.5% sodium hypochlorite and 2% chlorhexidine gel were more effective in eliminating C. albicans and E. faecalis...

Increased Survivorship and Altered Cytokine Profile from Treatment of Influenza A H1N1-Infected Mice with Ekybion: A Drug Complex of Natural Extracts and Inorganic Compounds

Lupfer, Christopher; Besnouin, Didier; Tepper, Samuel E.; Maselko, Maciej; Patton, Kristin M.; Pastey, Manoj
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
45.91%
Ekybion is a drug complex of 16 natural extracts and inorganic compounds designed to treat a variety of respiratory pathogens of bacterial and viral origin. It is licensed throughout Europe for the treatment of respiratory tract infections from equine parainfluenza type 3 and equine herpes virus type 1 in equine stables. The purpose of this paper was to test the efficacy of Ekybion on a well-developed animal model of influenza A infection and determine a mode of action. Experiments were performed with Balb/c mice infected with a lethal dose of influenza A/PR/8/34 H1N1 virus and treated with nebulized Ekybion every 8 h in a time-dependant or dose-dependant fashion. These experiments showed that mice treated prior to infection with Ekybion had a higher survival rates (~46%) compared with untreated animals (~0%). Paradoxically, these mice showed no significant difference in lung virus titer or weight loss. There was, however, a decrease in the level of GM-CSF, IL-6, and G-CSF cytokines in the lungs of Ekybion-treated, infected mice. It is possible that decreases in proinflammatory cytokines may have contributed to increased survivorship in Ekybion-treated influenza-infected mice.

Mycoflora and Ochratoxin A Control in Wheat Grain Using Natural Extracts Obtained from Wine Industry By-Products

Alexa, Ersilia; Poiana, Mariana-Atena; Sumalan, Renata-Maria
Fonte: Molecular Diversity Preservation International (MDPI) Publicador: Molecular Diversity Preservation International (MDPI)
Tipo: Artigo de Revista Científica
Publicado em 19/04/2012 EN
Relevância na Pesquisa
46.12%
The aim of this study was to evaluate the effect of some natural extracts obtained from grape pomace (GPE) and grape seeds (GSE) as compared to a synthetic food, antioxidant-butylated hydroxytoluene (BHT), in order to control fungal population and ochratoxin A (OTA) production in naturally contaminated wheat. The results showed that the addition of these extracts was efficient with OTA content decreasing. On treatment with these extracts the loss of OTA content after 14 days was in the range 7.8–28.3% relative to the control sample, but increased up to 26.48–37% after 28 days. The highest loss in OTA content was recorded for treatment with GPE at the 500 ppm level. Regarding the fungal development, the obtained results show that the total fungal populations were significantly reduced by using natural extracts. The most efficient extract was GPE. Both BHT and GPE inhibit the growth of Penicillium verrrucosum, for all doses, but less with Aspergillus genera. GPE affects the growth of other types of moulds such as Rhizopus microsporus, Fusarium graminearum, Alternaria infectoria and Cladosporium herbarum. Our data suggested that GPE and GSE are able to provide fungicidal and fungistatic protection and to control the OTA accumulation in wheat...

LC-NMR Technique in the Analysis of Phytosterols in Natural Extracts

Horník, Štěpán; Sajfrtová, Marie; Karban, Jindřich; Sýkora, Jan; Březinová, Anna; Wimmer, Zdeněk
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
45.91%
The ability of LC-NMR to detect simultaneously free and conjugated phytosterols in natural extracts was tested. The advantages and disadvantages of a gradient HPLC-NMR method were compared to the fast composition screening using SEC-NMR method. Fractions of free and conjugated phytosterols were isolated and analyzed by isocratic HPLC-NMR methods. The results of qualitative and quantitative analyses were in a good agreement with the literature data.

Antioxidant activity of rosemary and oregano ethanol extracts in soybean oil under thermal oxidation

ALMEIDA-DORIA,R.F.; REGITANO-D'ARCE,Marisa A.B.
Fonte: Sociedade Brasileira de Ciência e Tecnologia de Alimentos Publicador: Sociedade Brasileira de Ciência e Tecnologia de Alimentos
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2000 EN
Relevância na Pesquisa
46.09%
Four experiments were conducted to measure the antioxidant activity of ethanol extracts of rosemary and oregano compared with synthetic antioxidants such as TBHQ and BHA/BHT. The antioxidant activity was determined and results differed from those of the Oven test at 63º C. Peroxide values and absorptivities at 232 nm of soybean oil under Oven test were lower in treatments with 25, 50, 75, 100 and 200 mg.Kg-1 TBHQ than in treatments with 1000 mg.Kg-1 oregano extract (O), 500 mg.Kg-1 rosemary extract (R) and their mixture R+O. All the treatments were effective in controlling the thermal oxidation of oils; the natural extracts were as effective as BHA+BHT and less effective than TBHQ. The natural extracts were mixed with 25, 50, 75 and 100 mg.Kg-1 TBHQ and then added to the oil. No improvement in antioxidative properties was observed. The best antioxidant concentration could be determined from polynomial regression and quadratic equation from the experimental data.

In vitro antimicrobial activity of auxiliary chemical substances and natural extracts on Candida albicans and Enterococcus faecalis in root canals

Valera, Marcia Carneiro; Maekawa, Lilian Eiko; Oliveira, Luciane Dias de; Jorge, Antonio Olavo Cardoso; Shygei, Erika; Carvalho, Claudio Antonio Talge
Fonte: Universidade de São Paulo. Faculdade de Odontologia de Bauru Publicador: Universidade de São Paulo. Faculdade de Odontologia de Bauru
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; Formato: application/pdf
Publicado em 01/04/2013 ENG
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Objective: The aim of this study was to evaluate the antimicrobial activity of auxiliary chemical substances and natural extracts on Candida albicans and Enterococcus faecalis inoculated in root canals. Material and Methods: Seventy-two human tooth roots were contaminated with C. albicans and E. faecalis for 21 days. The groups were divided according to the auxiliary chemical substance into: G1) 2.5% sodium hypochlorite (NaOCl), G2) 2% chlorhexidine gel (CHX), G3) castor oil, G4) glycolic Aloe vera extract, G5) glycolic ginger extract, and G6) sterile saline (control). The samples of the root canal were collected at different intervals: confirmation collection, at 21 days after contamination; 1st collection, after instrumentation; and 2nd collection, seven days after instrumentation. Microbiological samples were grown in culture medium and incubated at 37°C for 48 hours. Results: The results were submitted to the Kruskal-Wallis and Dunn (5%) statistical tests. NaOCl and CHX completely eliminated the microorganisms of the root canals. Castor oil and ginger significantly reduced the number of CFU of the tested bacteria. Reduction of CFU/mL at the 1st and 2nd collections for groups G1, G2, G3 and G4 was greater in comparison to groups G5 and G6. Conclusion: It was concluded that 2.5% sodium hypochlorite and 2% chlorhexidine gel were more effective in eliminating C. albicans and E. faecalis...