Antimicrobial Efficacy of Moss Bryum argenteum (Hedw.) (Bryales: Bryaceae) against Plant Pathogen Pseudomonas syringae (PV.) (Pseudomonadales: Pseudomonadaceae)

Abstract

Introduction: Bryophytes are considered as a remarkable reservoir of new, natural products or secondary compounds, many of which have shown interesting biological activity. Biological activities of number of liverworts and mosses were studied which suggests that they contain a large number of terpenoids and phenolic compounds. Aims: To assess antimicrobial activity of moss Bryum argenteum (Hedw.) (Bryales: Bryaceae) methanolic crude extract against plant pathogen Pseudomonas syringae (pv.) (Pseudomonadales: Pseudomonadaceae). Study Design: In vitro testing. Methodology: In vitro antimicrobial activity of moss B. argenteum was evaluated by using different concentrations of methanolic crude extract for number of bacterial colonies formation and zone of inhibition. Antibiotic drugs such as amoxillin and streptomycin were used as positive control. Phytochemical screening was performed according to the methods described by Raman (2006) to determine the presence of various bioactive antimicrobial compounds. Methanolic crude extract of B. argenteum was analyzed for the presence of secondary metabolites using a Perkin Elmer series 200 HPLC system. Results: Methanolic crude extract of B. argenteum had significant antibacterial potential. Number of bacterial colonies decreased with increased concentrations of B. argenteum extract. Zone of inhibition was increased from lower to higher concentration of the extract. The results were confirmed with the different concentrations of commercially available antibiotic drugs, amoxillin and streptomycin. Decreased number of colonies and increased size of zone of inhibition of test bacterium P. syringae suggests that moss B. argenteum possesses high antibacterial efficacy. α-terpineol was confirmed by HPLC analysis. Conclusion: Present study indicates that natural antimicrobial agents of B. argenteum showed inhibitory effect on in vitro growth of phytopathogenic bacterium P. syringae in form of number of colonies and zone of inhibition.