164 resultados para xanthone glycoside
Resumo:
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Resumo:
Este estudo visou identificar substâncias biologicamente ativas e o potencial alelopático de esteroides glicosilados, provenientes das sementes de Annona crassiflora. O isolamento dos esteroides glicosilados foi realizado com a separação dos constituintes químicos do extrato bruto de acetato de etila em coluna cromatográfica, sendo a completa elucidação estrutural por meio de espectroscopia de RMN 1H. Testes de germinação com as espécies Euphorbia heterophylla e Ipomoea grandifolia foram conduzidos em câmaras tipo BOD a 25ºC e fotoperíodo de 12 horas, monitorados durante 10 dias com avaliação diária, nas concentrações de 0, 20, 40, 80 e 100 mg L-1 dos materiais isolados. Utilizando as mesmas concentrações, os experimentos de desenvolvimento de radícula e hipocótilo foram mantidos em câmara de germinação a 25ºC e fotoperíodo de 24 horas, com avaliação no décimo dia. Após o extrato de acetato de etila ser submetido ao fracionamento, verificou-se a presença de sinais característicos de fitoesteróis no espectro do RMN 1H, resultando em uma mistura de estigmasterol glicosilado e sitosterol glicosilado. Os resultados indicam que as substâncias estigmasterol e sitosterol não proporcionaram inibição na germinação e no índice de velocidade de germinação (IVG) de E. heterophylla e I. grandifolia. Por outro lado, estigmasterol e sitosterol interferiram no desenvolvimento de radícula e hipocótilo de E. heterophylla.
Resumo:
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Resumo:
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Resumo:
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Resumo:
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
Rheumatoid arthritis (RA) is a chronic illness with great potential to cause comorbidities resulting from cumulative inflammatory activities, and it contributes with the increase of disabilities and death of patients. It affects 1 to 2% of world population and usually occurs between 30 and 50 years of age. Among existing therapeutic options for the disease non-steroidal anti-inflammatory drugs (NSAIDs) still play an important part in the treatment, being widely used by patients to relieve pain and stiffness. However, this class of drugs causes many adverse gastrointestinal effects, such as dyspepsia, heartburn, nausea and vomit, and its use is one of the most common causes of peptic ulcers. Mangiferin (a glicosilated xanthone extracted mainly from the bark of Mangifera indica L.) is the main compound of an aqueous extract made from the bark stem of the mango tree. Previous studies conducted by our research group prove the anti-inflammatory action of mangiferin on an animal model of periodontitis, and its gastroprotective action has been described before. Considering these informations this study evaluated mangiferin’s potential on the treatment of RA and on gastric ulcer healing in animal models, and analyzed toxicity parameters to assure efficacy and safety of the compound as potential new drug for the treatment of the disease. RA was induced in rats by subcutaneous injection of bovine collagen and Freund’s complete adjuvant. This method presented low incidence of RA in rats, but we were able to induce the disease in 60 to 70% of the animals. Due to the wide use of NSAIDs and its potential to cause peptic ulcers, we induced gastric ulcer on arthritic rats to analyze mangiferin’s gastric healing effect. After 14 days of treatment we noticed small increase of the lesion area of animals treated with mangiferin or ibuprofen, when compared to the animals... (Complete abstract click electronic access below)
Resumo:
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
Asclepias subulata Decne. is a shrub occurring in Sonora-Arizona desert (Mexico-USA). The ethnic groups, Seris and Pimas, use this plant for the treatment of sore eyes, gastrointestinal disorders and cancer. To isolate the compounds responsible for antiproliferative activity of the methanol extract of A. subulata. A bioguided fractionation of methanol extract of A. subulata was performed using MTT assay to measure the antiproliferative activity of different compounds on three human cancer cell lines (A549, LS 180 and PC-3), one murine cancer cell line (RAW 264.7) and one human normal cell line (ARPE-19). The methanol extract was partitioned with hexane, ethyl acetate and ethanol. The active fractions, ethanol and residual, were fractioned by silica-column chromatography and active sub-fractions were separated using HPLC. The chemical structures of isolated compounds were elucidated with different chemical and spectroscopic methods. A new cardenolide glycoside, 12, 16-dihydroxycalotropin, and three known, calotropin, corotoxigenin 3-O-glucopyranoside and desglucouzarin, were isolated of active sub-fractions. All isolated compounds showed a strong antiproliferative activity in human cancer cells. Calotropin was the more active with IC50 values of 0.0013, 0.06 and 0.41 µM on A549, LS 180 and PC-3 cell lines, respectively; while 12, 16-dihydroxycalotropin reached values of 2.48, 5.62 and 11.70 µM, on the same cells; corotoxigenin 3-O-glucopyranoside had IC50 of 2.64, 3.15 and 6.62 µM and desglucouzarin showed values of 0.90, 6.57 and 6.62, µM. Doxorubicin, positive control, showed IC50 values of 1.78, 6.99 and 3.18 µM, respectively. The isolated compounds had a weak effect on murine cancer cells and human normal cells, exhibiting selectivity to human cancer cells. In this study, we found that 12, 16-dihydroxicalotropin, calotropin, corotoxigenin 3-O-glucopyranoside and desglucouzarin are responsible of antiproliferative properties of A. subulata, and that these compounds are highly selective to human cancer cells. Further studies are needed in order to establish the action mechanisms of the isolated compounds.
Resumo:
The aim of the present study was to investigate the effect of isofl avones supplementation of a fermented soy product on its sensory acceptance, physicochemical properties and probiotic cell viable count. Additionally we also investigated the ability of the mixed starter cultures (Enterococcus faecium CRL 183 and Lactobacillus helveticus 416) to modify the isofl avones profi le of soy product during the fermentation process. Three products were analysed: soy product fermented with E. faecium CRL 183 and L. helveticus 416, isofl avonessupplemented soy product (fermented with E. faecium CRL 183 and L. helveticus 416; 50mg/100g, Isofl avin®, Galena, Brazil) and unfermented soy product. A panel of judges evaluated the acceptability of the samples on a nine point structured hedonic scale. The chemical composition namely fat, protein, ash and total carbohydrate contents, pH, enumeration of viable Lactobacillus spp. and Enterococcus spp. and quantifi cation of isofl avones using HPLC were investigated. All determinations were conducted after 7 days storage at 10°C. The sensorial acceptance was reduced in the isofl avones-supplemented soy product, but this effect was not signifi cant compared to the sample without isofl avones addition. Chemical composition did not differ (p<0.05) among the samples. Cell viable counts were reduced and total fermentation time was longer in the isofl avonessupplemented soy product, suggesting that the isofl avone addition could inhibit the starter cultures. However, all the products may be considered probiotic since they exhibited lactic acid bacterial populations varying from 2.3 x 109 up to 1.22 x 1010 CFU/mL. Fermentation of soymilk did not change the isofl avones profi le. In conclusion, it was possible to obtain a fermented soy product containing a high isofl avones concentration, adequate sensory and chemical characteristics and lactic acid bacterial viability suffi ciently high to characterize the product as a probiotic. The mixed starter culture was not able to convert the glycoside isofl avones into aglycone or produce equol during the fermented soy product processing.
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
Pós-graduação em Microbiologia Agropecuária - FCAV
Resumo:
SUMMARY: Federal Urban Rat Control Program grants were awarded to cities in different areas of the United States. Severe problems of rat infestations have been detected in many of the cities by the Environmental Health Service. Approximately 20% of 3.8 million people in the project areas were occupying homes infested with rats. Control operations are now in effect in all cities, and the living conditions of the people have been substantially improved. An increase in interest in rodent control also is evident in countries outside of the United States. The Technical Development Laboratories of the National Communicable Disease Center are participating in the World Health Organization program of research on new rodenticides. The evaluation program involves five steps which carry a candidate toxi¬cant from laboratory phase through field testing. Acceptability and suitable concentrations of both acute and accumulative rodenticides are determined. Observations are made on the hazard of the compound to pets and to other nontarget vertebrates. Laboratory and field studies have been completed on a new, promising stabilized scilliroside glycoside which has given excellent control of the Norway rat in 16 out of 19 premises. Another new coded compound has shown a unique specificity for roof rats as compared to Norway rats. Although anticoagulant resistant rat populations have occurred in several countries in Europe, as yet no evidence has been noted of such resistance in rats in the United States.