In vitro antibacterial activity of various tissue types of Dumortiera hirsuta (Sw) Nees from different altitudes of eastern Himalaya

Abstract Objective To study the antibacterial activity of methanol and ethanol extracts of vegetative, male sexual and female sexual reproductive thalli of the bryophyte Dumortiera hirsuta collected from five different altitudes of eastern Himalaya against some human pathogenic bacteria. Methods Well diffusion method, determination of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were carried out against strains of human pathogenic bacteria. Results Different tissue types of the bryophyte collected from various altitudes have shown to inhibit the human pathogenic bacterial strains in vitro. Maximum antibacterial activity was noted against S. marcescens (ATCC 13880) for both the 80% methanolic and ethanolic extracts of both the vegetative and the reproductive thalli. The extracts of the reproductive thallus showed less antibacterial activity than that of the vegetative thallus. Specimens collected from higher altitude showed slightly lesser antibacterial activity than their lower altitude counterparts. Conclusions Antibiotic activity was noted to be dependent on solvent system used for extraction, altitude and tissue type. Analyses of extracts may yield some bioactive molecule responsible for antibacterial efficacy of the bryophyte.