Medicinal plants: an alternative source for antimicrobials against emerging pathogens

This thesis is submitted in partial fulfillment of the requirements for the degree of Bachelor of Science in Microbiology, 2014.Cataloged from PDF version of thesis.Includes bibliographical references (page 61-62).Tagetes erecta, an extensively used medicinal plant is a small shrub which grows up to 1-2 mm. The present study was aimed to investigate the antibacterial activity of this locally available plant. Antimicrobial activity of three different crude extracts (cold aqueous, hot aqueous and methanol extracts) of Tagetes erecta leaves and flowers was evaluated by disk diffusion method against seven different pathogenic gram positive and gram negative bacteria. The leaf and flower of this plant part found to show a broad spectrum of antibacterial activity. All the extracts were found effective though the hot aqueous extract showed maximum inhibition against the test microorganisms followed by cold aqueous and methanol extracts. Current results will provide a background for further endeavor in development of antimicrobial agents from this important medicinal plant.Monisha Datta TrishaB. Microbiolog