Acute toxicity and antimicrobial activity of leaf tincture Baccharis trimera (Less).

Biomed J. 2018 Jun;41(3):194-201. doi: 10.1016/j.bj.2018.04.006. Epub 2018 Jul 11. da Silva ARH1, Lopes LQS2, Cassanego GB3, de Jesus PR3, Figueredo KC3, Santos RCV2, Lopes GHH4, de Freitas Bauermann L3. Author information 1 Department of Physiology and Pharmacology, Federal University of Santa Maria, Santa Maria, RS, Brazil. Electronic address: andreiaregina_silva@yahoo.com.br. 2 Department of Microbiology and Parasitology, Federal University of Santa Maria, Santa Maria, RS, Brazil. 3 Department of Physiology and Pharmacology, Federal University of Santa Maria, Santa Maria, RS, Brazil. 4 Department of Technology and Food Science, Federal University of Santa Maria, Santa Maria, RS, Brazil. Abstract BACKGROUND: The present study aimed to evaluate the possible acute oral toxicity of Baccharistrimera leaf dye as well as its antimicrobial activity. METHOD: Organization for Economic co-operation and development (OECD) 423 was used to assess acute oral toxicity and as per protocol a dose of 2000 mg/kg of tincture was administered to Wistar rats, male and female, and observed for 14 days. Biochemical and hematological analyzes were performed with sample collected of rat. The dye was evaluated for antimicrobial activity by agar diffusion and microdilution methods, which allow to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) and antibiofilm potential. RESULTS: The results showed that there was no loss of animals and no significant changes in hematological and biochemical parameters after oral administration of 2000 mg/kg of tincture and was considered safe by the OECD, classified as category 5. The dyeing also showed an important antimicrobial activity against gram positive and gram negative bacteria also significantly decreased the microbial biofilm. CONCLUSION: The tincture of B.trimera leaf when given orally once can be considered safe and has a relevant antimicrobial potential that should be elucidated in subsequent research. Copyright © 2018 Chang Gung University. Published by Elsevier B.V. All rights reserved. KEYWORDS: Antimicrobial activity; Carqueja; Medicinal plants; Toxicity PMID: 30080659 DOI: 10.1016/j.bj.2018.04.006 Free full text