RESUMEN
ABSTRACT A new C-glycosylflavone, apigenin 7-methyl ether 6-C-[β-xylopyranosyl-(1→3)-β-glucopyranoside] named distemonanthoside was isolated from the stem bark of Distemonanthus benthamianus Baill., Fabaceae, along with six known compounds, sitosterol 3-O-β-D-glucopyranoside, 4-methoxygallic acid, syringic acid, quercetin, 6"-O-acetylvitexin, quercetin 3-O-β-D-glucopyranoside. The structures of those compounds and others were determined through spectral analyses. Compounds distemonanthoside, sitosterol 3-O-β-D-glucopyranoside, 4-methoxygallic acid and quercetin were tested against a clinical isolate strain of Mycobacterium tuberculosis AC 45; they exhibited good to moderate antitubercular activities with MIC values ranged from 31.25 to 125 µg/ml.
RESUMEN
Modern civilization is facing hundreds of disorders associated with free radicals. The natural antioxidants from non-edible plants are gaining importance to fight against these disorders. The intention of this study is to evaluate the petroleum ether, chloroform and methanol extracts of roots of Leucas marrubioides Desf. (Lamiaceae) for antioxidant and antitubercular activities. The antioxidant activity of the extracts has been evaluated using DPPH radical scavenging, reducing power and nitric oxide scavenging methods. The results of the study indicated that, methanol extract posses promising DPPH radical scavenging, reducing power and nitric oxide scavenging activity. The petroleum ether and chloroform extracts showed moderate antioxidant activity in all the three models. The antitubercular activity of all the extracts of L. marrubioides have been evaluated against Mycobacterium tuberculosis H73Rv strain using Microplate Alamar Blue Assay (MABA). The activity was documented within MIC range of 0.2 to 100μg/ml. The results of MABA showed that petroleum ether extract exhibited excellent antitubercular activity. The chloroform extract is moderately active, whereas methanol extract is less active against M. tuberculosis. The present investigation suggests that L. marrubioides posses remarkable antioxidant and antitubercular activity.
RESUMEN
2-Aryl/heteryl-3-aryloxy/heteryloxy-4H-chromones 5 have been synthesized through a series of reactions starting from phenols under microwave irradiation. This process is an effective alternative to the traditional thermal heating method. The yields are excellent and the reaction time is in a few minutes. These compounds have been characterized on the basis of IR, 1H NMR, 13C NMR and Mass spectrometry and evaluated for antibacterial activity.
RESUMEN
O objetivo deste trabalho foi realizar uma seleção de algumas plantas de uma determinada região Brasileira com atividade contra Mycobacterium tuberculosis. Extratos clorofórmicos e metanólicos de 37 espécies de plantas distribuídas em 17 famílias do "Cerrado" Brasileiro foram avaliadas contra M. tuberculosis H37Rv e a Concentração Inibitória Mínima (CIM) foi determinada pelo uso do Microplate Alamar Blue Assay (MABA). Extratos brutos de dezesseis plantas apresentaram valor de CIM < 125 µg/mL e três de 31,2 µg/mL. Estes resultados sugerem que o "Cerrado" Brasileiro deve possuir um recurso de plantas com constituintes ativos anti-M. tuberculosis que podem ser extraídos por solventes polares e apolares.
The aim of this work was to carry out a screening of some plants of this Brazilian region with activity against Mycobacterium tuberculosis. Chloroform and methanol extracts of 37 plant species distributed among 17 families from Brazilian "Cerrado" which were tested against M. tuberculosis H37Rv and the Minimum Inhibitory Concentration (MIC) was determined by the use of Microplate Alamar Blue Assay (MABA). Crude extracts from sixteen plants showed MIC value of < 125 µg/mL and three 31.2 µg/mL. These results suggest that the Brazilian "Cerrado" may be a source of plants that have activity anti-M. tuberculosis constituents that can be extracted by polars and apolars solvents.