Investigation of local anesthetic and antimycobacterial activity of Ottonia martiana Miq. (Piperaceae).

Ottonia martiana is a plant popularly known in Brazil by the use for toothache. Ethanolic extract (EE), hexane fraction (HF), dichloromethane fraction (DF) and piperovatine obtained from O. martiana were assayed in vitro and in vivo. The acute toxicity of EE was determined, and LD50 values of 164.5 and 65.0 mg/kg by the oral and intraperitoneal routes, respectively, indicated a high toxicity for EE in vivo, explaining its popular use by topical administration only. A local anesthetic-like effect of EE and its fractions was observed in experimental models using pain induction, and such effect involved an analgesic action. The antimycobacterial activity of EE, HF, DF and piperovatine was evaluated against Mycobacterium tuberculosis H37Rv ATCC 27924. EE, HF, DF, and piperovatine showed a potential antimycobacterial effect with MICs of 16.0, 62.0, 62.0 and 8.0 µg/mL, respectively. Piperovatine was more effective than the EE or the other fractions. The selectivity index (SI=IC50/MIC) values calculated for EE, HF, DF and piperovatine based on the MICs and the cytotoxicity against J774 macrophages (IC50 by MTT assay) revealed values of 6.43, 2.34, 1.5 and 9.66, respectively.

Atividade antibacteriana e antifúngica de extratos etanólicos de Aster lanceolatus Willd., Asteraceae / Antibacterial and antifungal activity of ethanolics extracts from Aster lanceolatus Willd., Asteraceae

Conhecida popularmente como áster-arbustiva, margarida-de-são-miguel e monte-cassino, Aster lanceolatus é uma planta ornamental de corte. Sabendo-se que não existem estudos que atestem a atividade biológica desta espécie, procurou-se neste trabalho atividades antibacteriana e antifúngica. Para tanto se utilizaram extratos brutos etanólicos de duas porções distintas, das flores e dos caules com folhas. Para a atividade antibacteriana, oito bactérias patogênicas foram submetidas a ensaio de difusão em gel e concentração inibitória mínima. Demonstrou-se atividade do extrato bruto etanólico de flores contra Streptococcus pyogenes, em difusão em gel e atividade de extrato bruto etanólico de caules e folhas contra Salmonella typhimurium e Streptococcus pyogenes em concentração inibitória mínima. Para a atividade antifúngica, utilizaram-se três fungos patogênicos em ensaios de crescimento micelial em placas e bioautografia direta. No ensaio de crescimento micelial em placas verificou-se a inibição de Fusarium oxysporum e na bioautografia direta, inibição do Cylindrocladium spathulatum. Os resultados delinearam uma nova fonte de pesquisa, as plantas ornamentais. Estas podem ser fonte de constituintes químicos capazes de servirem como protótipos para novos agentes terapêuticos e para tratamento sanitário de plantas medicinais.

Popularly known as aster-arbustiva, margarida-de-são-miguel and monte-cassino, Aster lanceolatus is an ornamental plant. Having the knowledge that there is no studies on the biological activity of this species, this work aimed to check the antibacterial and antifungal activities. The ethanol extracts of the flowers and of the stems with leaves were used. For the antibacterial activity eight pathogenic bacteria were submitted to the diffusion test in gel and minimal inhibitory concentration. The activity of the ethanolic extract of the flowers has been demonstrated against Streptococcus pyogenes in diffusion in gel and the activity of the ethanol extract of the stems and leaves against Salmonella typhimurium and Streptococcus pyogenes in minimal inhibitory concentration. For the antifungal activity, three pathogenic yeasts have been used in the micelial growth tests in plates and direct bioautography. In the micelial growth tests in plates the inhibition of Fusarium oxysporum has been verified and in the direct bioautography, inhibition of the Cylindrocladium spathulatum. The results indicated a new research source, the ornamental plants. These can be the source of chemicals capable of serving as prototypes for new therapeutic agents and for sanitary treatment of medicinal plants.