ABSTRACT
Abstract Recent publications have highlighted the numerous biological activities attributed to the lignan (-)-cubebin (1), Piper cubeba L. f., Piperaceae, and ongoing studies have focused on its structural optimization, in order to obtain derivatives with greater pharmacological potential. The aim of this study was the obtainment of (1), its semisynthetic derivatives and evaluation of antibacterial activity. The extract of the seeds of P. cubeba was chromatographed, subjected to recrystallization and was analyzed by HPLC and spectrometric techniques. It was used for the synthesis of: (-)-O-methylcubebin (2), (-)-O-benzylcubebin (3), (-)-O-acetylcubebin (4), (-)-O-(N, N-dimethylamino-ethyl)-cubebin (5), (-)-hinokinin (6) and (-)-6.6'-dinitrohinokinin (7). The evaluation of the antibacterial activity has been done by broth microdilution technique for determination of the minimum inhibitory concentration and the minimum bactericidal concentration against Porphyromonas gingivalis, Prevotella nigrescens, Actinomyces naeslundii, Bacteroides fragilis and Fusobacterium nucleatum. It was possible to make an analysis regarding the relationship between structure and antimicrobial activity of derivatives against microorganisms that cause endodontic infections. The most promising were minimum inhibitory concentration =50 µg/ml against P. gingivalis by (2) and (3), and minimum inhibitory concentration =100 µg/ml against B. fragilis by (6). Cytotoxicity assays demonstrated that (1) and its derivatives do not display toxicity.
ABSTRACT
Abstract Schistosomiasis, a chronic disease that affects million people worldwide, is caused by trematode flukes of the genus Schistosoma. The lack of an anti-schistosomiasis vaccine and massive monotherapy with praziquantel reinforces the need for search and development of new therapeutic drugs. Recently, we demonstrated that the essential oil of Piper cubeba L., Piperaceae, and their derivative dibenzylbutyrolactolic (-)-6,6'-dinitrohinokinin, presents in vitro and in vivo activities against Schistosoma mansoni. Here, we identified changes in the protein expression after exposure to dibenzylbutyrolactolic (-)-6,6'-dinitrohinokinin. We applied two-dimensional gel electrophoresis (2-DE) to S. mansoni soluble protein extracts and observed at least 38 spots to be affected by dibenzylbutyrolactolic (-)-6,6'-dinitrohinokinin. We further identified 25 differentially expressed proteins by mass spectrometry. Enrichment for biological processes and predictive analyses of protein-protein interactions suggest that dibenzylbutyrolactolic (-)-6,6'-dinitrohinokinin targets proteins involved mainly in metabolic processes, especially carbohydrate metabolism. In summary, this study provides an interesting approach to understand the anti-parasitic activity of semi-synthetic (-)-6,6'-dinitrohinokinin a derivative compound from lignan and for the development of new therapy strategies.
ABSTRACT
The Copaifera langsdorffii Desf., Fabaceae, is a Brazilian native tree, known as copaiba, which oil is commonly used in folk medicine as muscle relaxant, wound healing, antiseptic and anti-inflammatory to respiratory and urinary tracts. Despite of the wide use of the oil of Copaifera species, scientific works related to the study of its leaves are rarely found. In fact, processes for flavonoid extraction from C. langsdorffii leaves have not been studied yet leaving a wide field to be investigated. In this work, the 2(5-2) fractional factorial design was selected in order to study how the factors of a dynamic maceration process influence the responses of total flavonoids, total phenols, quercetrin and afzelin contents, and antioxidant activity in extracts from C. langsdorffii leaves. The results demonstrated that the significant factors studied were the drug load in extractor, the ethanol/water ratio and the stirring speed whereas the temperature and the extraction time were not significant. In conclusion, this study allowed visualizing which factors were considered the most important in copaiba leaves dynamic maceration and their effect in extract antioxidant activity. Furthermore, this technological study gives directions to optimize future extraction experiments from C. langsdorffii.
ABSTRACT
Este trabalho descreve a validação completa de metodologia analítica empregando cromatografia gasosa capilar com padronização interna para quantificação da cumarina (1,2-benzopirona) em produtos contendo guaco (Mikania glomerata Spreng - Asteraceae): xarope, planta e extrato padronizado, além do estudo de estabilidade do fitoterápico em questão. Utilizou-se uma coluna capilar HP-5 (30 m x 0,32 mm x 0,25 µm), hidrogênio a 1,8 mL/min e rampa de temperatura de 100 ºC a 250 ºC, a 15 ºC/min. A temperatura do injetor (split 1:20) foi de 250 ºC, enquanto a do detector foi de 270 ºC. Os tempos de retenção dos padrões foram: 2,86 minutos para o 1, 2, 3, 4-tetrametilbenzeno, 4,45 minutos para o piperonal (padrões internos) e 5,36 minutos para a cumarina. Após o procedimento de extração da planta in natura, a recuperação da cumarina foi de 101,6 por cento, enquanto que para o xarope esta foi de 100,8 por cento. Os limites de detecção e quantificação foram 0,5 µg/mL e 1,5 µg/mL, respectivamente. A precisão, determinada para todas as amostras, apresentou desvios padrões relativos menores que 2,5 por cento. Os teores de cumarina presentes nas folhas, extrato e xarope foram de 0,38 por cento m/m, 1,33 mg/mL e 0,143 mg/mL, respectivamente.
This work describes a full validation of a capillary gas chromatography analytical methodology using internal standardization for the quantification of coumarin (1,2-benzopyrone) in guaco (Mikania glomerata Spreng - Asteraceae) products: syrup, plant and its extract, including the stability study of the phytomedicine. For the analysis, it was used an HP-5 capillary column (30 m x 0.32 mm x 0.25 µm), hydrogen at a flow rate of 1.8 mL/min and the increasing temperature gradient was: 100 ºC to 250 ºC, 15 ºC/min. The temperature of injector (split 1:20) and detector were kept at 250 ºC and 270 ºC, respectively. The retention times of the standards for the above conditions were 2.86 minutes for 1, 2, 3, 4-tetramethylbenzene, 4.45 min for piperonal (internal standards), and 5.36 minutes for coumarin. After extraction procedure, the recovery of coumarin determined for plant raw material was 101.6 percent, while for syrup it was 100.8 percent. Detection and quantification limits were 0.5 µg/mL and 1.5 µg/mL, respectively. Precision was determined for all samples and the results were lower than 2.5 percent. The total amount of coumarin in plant raw material, its extract and syrup were 0.38 percent w/w, 1.33 mg/mL and 0.143 mg/mL, respectively.
ABSTRACT
Própolis é um termo genérico utilizado para denominar o material resinoso e balsâmico coletado e processado pelas abelhas a partir de várias fontes vegetais. A composição da própolis é complexa e ocorrem variações em função de fatores como a flora da região, estações do ano e características genéticas das abelhas. Sendo assim, objetivou-se neste trabalho realizarem-se análises para o controle de qualidade físico-químico de amostras de própolis, provenientes de seis diferentes locais situados nas microrregiões de Franca (SP) e Passo (MG), bem como verificar a qualidade deste produto para o consumo humano e selecionar regiões produtoras de própolis verde. Os resultados obtidos para as diferentes análises variaram entre as seis diferentes áreas. As localidades de Capetinga-MG e o distrito de Chave da Taquara-SP produziram própolis verde durante todo o período de coleta. Além disso, as amostras de própolis provenientes destes locais mostraram-se satisfatórias para o consumo humano haja vista que os teores de flavonóides totais variaram entre 1 e 2 por cento p/p e os teores de ácidos fenólicos oscilaram entre 4 e 8 por cento p/p.
Propolis is a generic term used to denominate the resinous and balsamic material collected from several vegetable sources and processed by the bees. Its chemical composition is complex and depends on the plant species of the region, seasonality, and genetic characteristics of the bees. Therefore, the aim of this work was to establish the physical and chemical quality controls of propolis samples from six different Brazilian micro regions of Franca (SP) and Passos (MG), as well as to verify the propolis quality for human consumption, and to select green propolis producing areas. The obtained results for the different analyses varied among the six different sites. The sites of Capetinga (MG) and Chave da Taquara (SP) produced green propolis during the whole collection period. Besides, the analyses of propolis samples from these sites indicated that they are satisfactory for human consumption based on the total flavonoids content, which varied between 1 and 2 percent (w/w) and on the phenolic acids content, which varied between 4 and 8 percent (w/w).