Byrsonima fagifolia Niedenzu Apolar Compounds with Antitubercular Activity.

Bioassay-guided fractionation of the chloroform extract of Byrsonima fagifolia leaves led to the isolation of active antitubercular compounds alkane dotriacontane (Minimal Inhibitory Concentration-MIC, 62.5 µg mL(-1)), triterpenoids as bassic acid (MIC = 2.5 µg mL(-1)), α-amyrin acetate (MIC = 62.5 µg mL(-1)), a mixture of lupeol, α- and ß-amyrin (MIC = 31.5 µg mL(-1)) and a mixture of lupeol, and acetates of α- and ß-amyrin (MIC = 31.5 µg mL(-1)). The antimycobacterial activity was determined by the Microplate Alamar Blue Assay (MABA) and the structures of promising compounds were determined by spectroscopic analysis. This investigation constitutes the first report of a chemical and antitubercular study of apolar compounds from B. fagifolia Niedenzu (IK).

Plantas do cerrado brasileiro com atividade contra Mycobacterium fortuitum / Brazilian cerrado plants active against Mycobacterium fortuitum

Mycobacterium fortuitum é uma micobactéria de crescimento rápido, ubíquo na natureza e relacionada a micobacteriose de importância médica.Ela tem sido isolada de bacteremias, abscessos, endocardites, feridas cirúrgicas e traumáticas.De difícil tratamento, o bacilo é reconhecido na literatura como resistente inclusive aos medicamentos utilizados na terapêutica da tuberculose.O objetivo deste trabalho foi pesquisar extratos vegetais do Cerrado brasileiro com atividade contra M. fortuitum, empregando a técnica do Microplate Alamar Blue Assay (MABA) como método analítico.Dos 26 extratos testados frente ao M.fortuitum, o extrato apolar de Quassia amara (extrato diclorometanico) foi o que apresentou melhor resultado com valor de CIM de 62,5mg/mL seguidos pelos extratos apolares de Syngonanthus macrolepsis, Davilla elliptica, Turnera ulmifolia com CIM de 125g/mL.Para as mesmas plantas analisadas, utilizando-se agentes extratores polares (etanol e metanol), foram verificados CIM superiores a 500g/mL.Os valores foram semelhantes aos de extratos de outras plantas analisadas sendo considerados não promissores.

Antimycobacterial physalins from Physalis angulata L. (Solanaceae).

Crude extracts and fractions from aerial parts of Physalis angulata have been bioassayed for antimycobacterial activity. Fraction A1-29-12 containing physalins B, F and D exhibited a minimum inhibitory concentration value (MIC) against Mycobacterium tuberculosis H(37)Rv strain of 32 microg/mL. Purified physalin B and physalin D were also tested showing MIC values against Mycobacterium tuberculosis H(37)Rv strain of > 128 microg/mL and 32 microg/mL respectively, suggesting that physalin D plays a relevant role in the antimycobacterial activity displayed. Structural elucidation of both physalins D and B was based on detailed (13)C and (1)H NMR spectral analysis with the aid of 2D-correlation spectroscopy ((1)H-(1)H, COSY, HSQC and HMBC). The assignment of the (13)C chemical shift for physalin D is reported here for the first time.

In vitro antimycobacterial activities of Physalis angulata L.

The HIV-tuberculosis co-infection has caused an impact on tuberculosis epidemiology all over the world and the efficacies of the therapeutic schemes traditionally prescribed in the treatment of tuberculosis, such as isoniazid, rifampicin and pyrazinamide, have decreased due to the appearance of multidrug-resistant M. tuberculosis strains (MDR). This work is part of research on natural antimicrobial agents from plant extracts through bioassay-guided fractionation, by in vitro determination of the minimum inhibitory concentration (MIC) using the microdilution method with Alamar blue oxidation-reduction dye. Crude CHCl3 Physalis angulata extracts and physalin-containing fractions displayed antimycobacterial activity against Mycobacterium tuberculosis, Mycobacterium avium, Mycobacterium kansasii, Mycobacterium malmoense and Mycobacterium intracellulare.