Assay of antibacterial agents against drug resistant and drug sensitive bacteria and identification of biologically active principles from Ceriops tagal stem extracts

Abstract

Plants are being used as traditional medicine due to their active natural ingredients. Screening of plants for biologically active compounds against human pathogens mostly drug resistant strains is as renewed interest in research field. The main objective of this study is to evaluate the antibacterial potentialities of Ceriops tagal stem  extracts in  different solvents against drug resistant strains-Staphylococcus  aureus (MTCC87), Bacillus subtilis(MTCC 441),Bacillus cereus (MTCC430), Escherichia coli (MTCC40), Klebsiella pneumonia (MTCC39) and drug sensitive strains-Bacillus subtilis (MTCC121), Enterobacter aerogenes (MTCC111) and Pseudomonas aeruginosa (MTCC424) by agar-well diffusion method and qualitative   screening of bioactive principles. The crude stem extracts demonstrated broad spectrum activity against all bacteria tested with inhibition zones in the range of ≤1to≥14mm at about 20mg/ml concentration. The most active solvent extracts methanol, acetone, and alcohol and water range from 9 to ≥14mm on drug - resistant Gram-positive Staphylococcus aureus. Of the eight extracts studied only four extracts showed good antimicrobial activity against the tested   bacteria whereas remaining extracts were showed less activity. However the methanol   extracts of Ceriops tagal stem was found to be most active towards drug resistant Gram-positive Staphylococcus aureus. Qualitative screening of stem extracts shows that, this plant had potent source of alkaloids, flavonoids, saponins, steroids and terpenoids.