Antibacterial, antioxidant and cytotoxic activities of extracts of Conyza canadensis (L.) Cronquist growing in Tunisia

Abstract

Antibacterial antioxidant and cytotoxic activities of petroleum ether, ethyl acetate and methanol extracts of Conyza Canadensis (L.) Cronquist were investigated. Antibacterial activity was evaluated using the agar diffusion and microwell dilution assays against four strains of bacteria. Antioxidant activity was measured by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) method and the cytotoxic activity was tested against Hep-2 cells (laryngeal carcinoma cell line) using methylene blue assays. Among tested extracts, the methanolic extract exhibited important antibacterial activity. It also showed good antioxidant activity with 50% inhibition concentration (IC 50 ) of 120 lg/ml. Cytotoxicity of extracts was time depend, increasing with exposure time and concentration. At 72 h of incubation, the ethyl acetate and petroleum ether extracts demonstrated effective cytotoxic activity against Hep-2 cells with IC 50 values of 45 and 50 lg/ml, respectively.

Comparison of Three Herbal Plants for Best Free Radical Scavenging Activity

“…Our results were supported by other researches where a methanol extract of Conyzacanadensis exhibited good DPPH radical scavenging effect than its petroleum ether and ethyl acetate extracts [13]. It was reported that Lippiagraveolens, and Phoenix theophrasti [14] also exhibited strong DPPH scavenging activities.…”

The effect of nisin and garlic (Allium sativum L.) essential oil separately and in combination on the growth of Listeria monocytogenes

“…Briefly, the GO was dissolved in dimethyl sulfoxide (DMSO) (10 g/100 mL) (Hayet et al, 2009;Sahin et al, 2004) and then in BHI broth to achieve a concentration of 6400 mg/mL. Serial twofold dilutions were made in a concentration range from 25 to 3200 mg/mL in sterile test tubes containing BHI broth.…”

Antibacterial Activity of Medicinal Aqueous Plant Extracts against Mycobacterium tuberculosis

“…(Masoodi et al, 2008;Warda et al, 2009) and gram negative bacteria (Masoodi et al, 2008) but M. tuberculosis was not included. Also Marrubium alysson plant extract was found effective against different Enterobacteriaceae and different Candida species (Hayet et al, 2007). Many other plants were found to be having antimicrobial activity against TB using MGIT960 (Mariita et al, 2010) in the detection method while in this work antibiotics susceptibility test (AST) was used.…”