The first report on the in vitro antimicrobial activities of extracts of leaves of Ehretia serrata

Saudi J Biol Sci. 2019 Sep;26(6):1253-1261. doi: 10.1016/j.sjbs.2018.05.025. Epub 2018 May 24.

Abstract

The increasing resistance of infectious microbial organisms to the existing arsenal of antibiotic drugs is on the rise. There is a growing demand for the new antibiotics that are cost effective and easily available to the common people. In search of new antimicrobial entities, this report deals with the in vitro antimicrobial activities of the crude extracts of leaves of Ehretia Serrata. The methanolic extract and its sub-fractions namely n-hexane, chloroform, ethyl acetate, n-butanol and residual water fraction were screened against a range of 30 different bacterial strains and their zones of inhibition (ZI) and minimum inhibitory concentration (MIC) were subsequently evaluated. Methanolic extract has shown activity against all the tested microorganisms such as Azospirillum lipoferum, Escherichia coli, Pseudomonas aeruginosa, Stenotrophomonas maltophilia and Enterococcus sp. with ZOI ranged from 10.3 to 29.0 mm. Moreover, the MIC values of methanolic extract and its sub-fractions against the tested bacteria ranged from 0.8 to 5.1 mg/mL. GC-MS analysis of sub-fractions revealed the presence of mono (2-ethylexyl) 1,2-benzenedicarboxylate, diisooctyl-1,2-benzenedicarboxylate, 3,5-dehydro-6-methoxypivalate-cholest-22-ene-21-ol, and 3,5-bis (1,1-dimethylethyl)-4-hydroxybenzene-propanoic acid. This is the first report on the in vitro antimicrobial activities of leaves of E. Serrata.

Keywords: Antimicrobial activity; Boraginacae; Ehretia serrata; GC–MS analysis; Phytochemical studies.