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

Abstract

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 LD 50 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=IC 50 /MIC) values calculated for EE, HF, DF and piperovatine based on the MICs and the cytotoxicity against J774 macrophages (IC 50 by MTT assay) revealed values of 6.43, 2.34, 1.5 and 9.66, respectively.

Understanding the Cerrado biome, medicinal properties of a Piperaceae, and consequences of seasonal variation in Amazonian upland lakes

“…Among the more commonly used plants in tropical and subtropical areas are the Piperaceae (e.g., Cunico et al 2015). In the present issue of the AABC, López et al (2016) explore the anesthetic activity of Ottonia anisum, a Piperaceae that is commonly found in the Atlantic forest, confirming its efficiency.…”