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1.
Photochem Photobiol ; 89(2): 391-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23057576

RESUMO

Antioxidant compounds protect plants against oxidative stress caused by environmental conditions. Different light qualities, such as UV-A radiation and blue light, have shown positive effects on the production of phenols in plants. Kalanchoe pinnata (Lamarck) Persoon (Crassulaceae) is used for treating wounds and inflammations. Some of these beneficial effects are attributed to the antioxidant activity of plant components. We investigated the effects of blue light and UV-A radiation supplementation on the total phenol content, antioxidant activity and chromatographic profile of aqueous extracts from leaves of K. pinnata. Monoclonal plants were grown under white light, white plus blue light and white plus UV-A radiation. Supplemental blue light improved the antioxidant activity and changed the phenolic profile of the extracts. Analysis by HPLC of supplemental blue-light plant extracts revealed a higher proportion of the major flavonoid quercetin 3-O-α-L-arabinopyranosyl (1→2) α-L-rhamnopyranoside, as well as the presence of a wide variety of other phenolic substances. These findings may explain the higher antioxidant activity observed for this extract. Blue light is proposed as a supplemental light source in the cultivation of K. pinnata, to improve its antioxidant activity.


Assuntos
Antioxidantes/metabolismo , Kalanchoe/efeitos da radiação , Fenóis/metabolismo , Folhas de Planta/efeitos da radiação , Quercetina/análogos & derivados , Kalanchoe/metabolismo , Luz , Oxirredução , Extratos Vegetais/química , Folhas de Planta/metabolismo , Quercetina/biossíntese
2.
Rev. bras. farmacogn ; 21(5): 835-840, Sept.-Oct. 2011. tab
Artigo em Inglês | LILACS | ID: lil-600975

RESUMO

Tuberculosis (TB), caused by Mycobacterium tuberculosis, is the world's number one killer among infectious diseases. The search for new naturalproducts that can act as drugs against TB has received increased attention duringthe last years. In this work we describe the isolation and identification of the active antimycobacterial principles of the dichloromethane extract from Lippia lacunosa Mart. & Schauer, Verbenaceae. Compounds were evaluated for their in vitro activity against Mycobacterium tuberculosis (susceptible and rifampicin resistantstrain) using a redox bioassay. From the dichloromethane extract of L. lacunosa leaves, seven methoxy-flavones named cirsimaritin (1), eupatilin (2), eupatorin (3), salvigenin (4), 3'-O-methyl-eupatorin (5), 3',7-dimethoxy-5,6,4'- trihydroxyflavone (6), and 7'-O-methylapigenin (7), and one triterpene, named oleanolic acid (8), were isolated. All compounds were found to display antimycobacterial activity against susceptible strain, with MIC ranging from 25 to 200 µg/mL. None of them was active against rifampicin resistant strain. This is the first report in the antimycobacterial activity of 6-substituted flavones, as well as the first report of the occurrence of these substances in L. lacunosa.

3.
An Acad Bras Cienc ; 83(2): 719-30, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21670890

RESUMO

The present work analyzes the different modalities of protection of the intellectual creations in the biotechnology agricultural field. Regarding the Brazilian legislations related to the theme (the Industrial Property Law - no. 9. 279/96 and the Plant Variety Protection Law - no. 9. 456/97), and based in the international treaties signed by Brazil, the present work points to the inclusions of each of them, as well as to their interfaces using as reference the case study of glyphosate tolerant genetically modified soybean. For this case study, Monsanto's pipelines patents were searched and used to analyze the limits of patent protection in respect to others related to the Intellectual Property (IP) laws. Thus, it was possible to elucidate the complex scenario of the Intellectual Property of the glyphosate tolerant soybeans, since for the farmer it is hard to correlate the royalties payment with the IP enterprise's rights.


Assuntos
Engenharia Genética/legislação & jurisprudência , Glycine max/genética , Glicina/análogos & derivados , Herbicidas/farmacologia , Propriedade Intelectual , Plantas Geneticamente Modificadas/genética , Brasil , Engenharia Genética/economia , Glicina/farmacologia , Resistência a Herbicidas/genética , Patentes como Assunto/legislação & jurisprudência , Plantas Geneticamente Modificadas/efeitos dos fármacos , Glycine max/efeitos dos fármacos , Glifosato
4.
An. acad. bras. ciênc ; 83(2): 719-730, June 2011. ilus, tab
Artigo em Inglês | LILACS | ID: lil-589926

RESUMO

The present work analyzes the different modalities of protection of the intellectual creations in the biotechnology agricultural field. Regarding the Brazilian legislations related to the theme (the Industrial Property Law - no. 9. 279/96 and the Plant Variety Protection Law - no. 9. 456/97), and based in the international treaties signed by Brazil, the present work points to the inclusions of each of them, as well as to their interfaces using as reference the case study of glyphosate tolerant genetically modified soybean. For this case study, Monsanto's pipelines patents were searched and used to analyze the limits of patent protection in respect to others related to the Intellectual Property (IP) laws. Thus, it was possible to elucidate the complex scenario of the Intellectual Property of the glyphosate tolerant soybeans, since for the farmer it is hard to correlate the royalties payment with the IP enterprise's rights.


O presente trabalho analisa as diferentes modalidades de proteção das criações intelectuais no campo da biotecnologia agrícola. A partir das leis Brasileiras relacionadas ao tema (Lei da Propriedade Industrial - nº 9.279/96 e Lei da Proteção de Cultivares - nº 9.456/97), e com base nos tratados internacionais assinados pelo Brasil, o presente trabalho aponta as inclusões de cada uma, assim como, suas interfaces usando como referência o estudo de caso da soja geneticamente modificada para tolerância ao glifosato. Para este caso, patentes pipelines da Monsanto foram buscadas e usadas para analisar os limites de proteção das patentes frente às outras leis de Propriedade Intelectual (PI) relacionadas. Assim, foi possível elucidar o cenário complexo da Propriedade Intelectual das sojas tolerantes ao glifosato, já que para o agricultor não é fácil correlacionar o pagamento dos royalties com os direitos de PI da empresa.


Assuntos
Engenharia Genética/legislação & jurisprudência , Glicina/análogos & derivados , Herbicidas/farmacologia , Propriedade Intelectual , Plantas Geneticamente Modificadas/genética , Glycine max/genética , Brasil , Engenharia Genética/economia , Glicina/farmacologia , Resistência a Herbicidas/genética , Patentes como Assunto/legislação & jurisprudência , Plantas Geneticamente Modificadas/efeitos dos fármacos , Glycine max/efeitos dos fármacos
5.
J Ethnopharmacol ; 133(1): 132-7, 2011 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-20883762

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Leaves from Kalanchoe pinnata (Lamarck) Persoon (Crassulaceae) are popularly used for healing wounds. Its antileishmanial properties are established in experimental animals, and its active flavonoid components have been identified. AIM OF THE STUDY: In this study, we attempted to standardize the extract from K. pinnata leaves by evaluating the influence of season of harvest, sunlight exposure and method of extraction on antileishmanial flavonoids content. MATERIALS AND METHODS: HPLC-DAD-MS was used to identify and quantify the active antileishmanial flavonoids in different extracts. ANOVA test for analyses of variance followed by the Tukey test of multiple comparisons were used in the statistical analysis. The antileishmanial potential was assessed by the activation of nitric oxide production by murine macrophage using the Griess method. RESULTS: We demonstrated that active flavonoids were significantly more abundant when the leaves were collected in the summer, and that aqueous extraction at 50°C allowed the highest flavonoid extraction. The benefit of sunlight exposure was confirmed in plants cultivated under direct sunlight when compared with those that grown under shade. Under sunny conditions the yield of the most active antileishmanial favonoid quercitrin was increased by 7-fold. All aqueous extracts tested were capable to enhance the macrophage nitric oxide production. However, hot aqueous extract from leaves collected in summer exhibited the higher activity, in agreement with HPLC-DAD-MS analysis tendency. In addition, with the aim of reducing the individual chemical variations of the plant constituents and optimizing the production of the active extract, it was obtained in vitro monoclonal KP specimens that were easily adapted to field conditions and were able to produce antileishmanial flavonoids. CONCLUSION: Our study reports the better conditions of cultivation, harvest and extraction protocol for obtaining a K. pinnata extract exhibiting the highest antileishmanial activity. Additionally, we propose the flavonoids quercetin 3-O-α-L-arabinopyranosyl (1→2)-α-L-rhamnopyranoside and quercitrin, as satisfactory chemical markers for standardization purposes.


Assuntos
Antiprotozoários/química , Flavonoides/análise , Kalanchoe/química , Leishmaniose/tratamento farmacológico , Extratos Vegetais/química , Estações do Ano , Animais , Antiprotozoários/farmacologia , Flavonoides/farmacologia , Kalanchoe/crescimento & desenvolvimento , Macrófagos/efeitos dos fármacos , Camundongos , Óxido Nítrico/metabolismo , Fitoterapia , Extratos Vegetais/farmacologia , Folhas de Planta
6.
Rev. bras. farmacogn ; 19(3): 697-701, jul.-set. 2009. ilus, tab
Artigo em Inglês | LILACS | ID: lil-537912

RESUMO

Leaf oil prepared by hydrodistillation of Alpinia zerumbet Pers.) B.L. Burtt & R.M. Sm. was analyzed by GC/FID and GC/MS to determine the major compounds and it was also evaluated for antimicrobial activity. The oil presented a high content of oxygenated monoterpenes (52.5 percent), terpinen-4-ol, 1,8 cineole and γ-terpinene as the major constituents. The antimicrobial activity of leaf oil was tested by drop diffusion and bioauthography methods. Through drop test, all bacteria and fungi tested were inhibited by leaf oil. Preparative TLC (thin-layer chromatography) plates were developed using the mobile phase hexane: ethyl acetate (70:20, v/v) and fractions of the leaf oil were separated in three zones, scraped, extracted from silica and identified by GC/MS. The bioauthography method permitted to verify pronounced inhibition of Cryptococcus neoformans by fractions F2 and F3, both rich in oxygenated monoterpenes. The fraction F2 comprised 1,8 cineole (9.6 percent), linalool (3.7 percent) and caryophyllene oxide (5.4 percent), while fraction F3 showed mainly terpinen-4-ol (43.6 percent) and an amount of 32.7 percent oxygenated sesquiterpenes. The obtained data may be used to suggest the constituents of A. zerumbet leaf oil involved in antimicrobial activity.


O óleo essencial de folhas de Alpinia zerumbet (Pers.) B.L. Burtt & R.M. Sm., extraído por hidrodestilação, foi analisado por CG/DIC e CG/EM a fim de se determinar sua composição e atividade antimicrobiana. O óleo apresentou um elevado teor de monoterpenos oxigenados (52,5 por cento): terpinen-4-ol, 1,8-cineol e γ-terpineno como principais constituintes. A atividade antimicrobiana do óleo foi analisada pelos testes de difusão em agar e ensaios de bioautografia. Através do teste de difusão em agar, todas as bactérias e fungos testados foram inibidos pelo óleo essencial. Placas preparativas de CCD (cromatografia em camada fina) foram eluídas em hexano: acetato de etila (70:20, v/v), e o óleo foi separado em três frações que foram raspadas, extraídas da sílica e identificadas por CG/EM. A análise bioautográfica permitiu detectar pronunciada inibição de Cryptococcus neoformans pelas frações F2 e F3, ambas ricas em monoterpenos oxigenados. A fração F2 apresentou 1,8 cineol (9,6 por cento), linalol (3,7 por cento) e óxido de cariofileno (5,4 por cento), enquanto a fração F3 mostrou principalmente terpinen-4-ol (43,6 por cento) e cerca de 32,7 por cento de sesquiterpenos oxigenados. Os dados obtidos indicam os componentes do óleo de A. zerumbet envolvidos na atividade antimicrobiana.

7.
J Nutr Biochem ; 13(7): 411-420, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12121828

RESUMO

From the seeds of Bixa orellana are extracted the carotenoids bixin and norbixin that have been widely used for coloring food. In this study, the toxicity of norbixin, purified or not (annatto extract containing 50% norbixin), was investigated in mice and rats after 21 days of ingestion through drinking water. Mice were exposed to doses of 56 and 351 mg/kg (annatto extract) and 0.8, 7.6, 66 and 274 mg/kg (norbixin). Rats were exposed to doses of 0.8, 7.5 and 68 mg/kg (annatto extract) and 0.8, 8.5 and 74 mg/kg (norbixin). In rats, no toxicity was detected by plasma chemistry. In mice, norbixin induced an increase in plasma alanine aminotransferase activity (ALT) while both norbixin and annatto extract induced a decrease in plasma total protein and globulins (P < 0.05). However, no signs of toxicity were detected in liver by histopathological analysis. No enhancement in DNA breakage was detected in liver or kidney from mice treated with annatto pigments, as evaluated by the comet assay. Nevertheless, there was a remarkable effect of norbixin on the glycemia of both rodent species. In rats, norbixin induced hyperglycemia that ranged from 26.9% (8.5 mg/kg norbixin, to 52.6% (74 mg/kg norbixin, P < 0.01) above control levels. In mice, norbixin induced hypoglycemia that ranged from 14.4% (0.8 mg/kg norbixin, P < 0.05) to 21.5% (66 mg/kg norbixin, P < 0.001) below control levels. Rats and mice treated with annatto pigments showed hyperinsulinemia and hypoinsulinemia, respectively indicating that pancreatic beta-cells were functional. More studies should be performed to fully understand of how species-related differences influences the biological fate of norbixin.

8.
Rev. bras. farmacogn ; 12(supl.1): 103-105, 2002.
Artigo em Português | LILACS | ID: lil-528772

RESUMO

Esse estudo tem por objetivo discutir como a forma de produção do conhecimento científico pode determinar a maneira do homem conhecer, lidar e apropriar-se da natureza, especificamente, em relação ao conhecimento associado ao estudo das plantas medicinais e seus derivados. Visando fornecer subsídios para a compreensão do que norteia os pesquisadores que buscam o entendimento sobre as plantas medicinais a partir de uma abordagem complexa, algumas questões de caráter epistemológico são formuladas e discutidas à luz dos referenciais teóricos construídos por Morin6 e Latour7.


This paper discusses how the form of production of scientific knowledge may determine the manner people know, deal with and appropriate nature, specifically, relatively to knowledge associated to medicinal plants and their derivatives. Some epistemologically questions are formulated and discussed under the light of theoretical referential after Morin6 and Latour7, to provide information to comprehend the reasons that direct researchers who search understanding about medicinal plants starting from a complex approach.

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