EVALUATION OF ANTIBACTERIAL ACTIVITY OF FRESH AND DRY FLOWER EXTRACTS OF CAESALPINIA PULCHERRIMA L.
The aim of present work is to screen out the antibacterial properties of flowers. Since plants are used as therapeutic agents, the present study is designed to evaluate the phytochemical profile and antibacterial activities of fresh and dry flower extracts of Caesalpinia pulcherrima L. against selective Gram positive & Gram negative strains invitro. The fresh and dry flowers of Caesalpinia pulcherrima L. were extracted by using solvents like n-hexane, chloroform, acetone, ethanol, methanol and water. Presence of phytoconstituents such as alkaloids, glycosides, saponins, carbohydrates, proteins, aminoacids, flavonoids, tannins, steroids were observed in fresh and dry flowers of C. pulcherrima. The antibacterial activity was studied by using various organisms by means of disc diffusion method. Susceptibility of some Gram positive (Staphylococcus aureus, Bacillus subtilis, Enterococcus faecalis) and Gram negative (Escherichia coli, Pseudomonas aeruginosa & Klebsiella pneumoniae) bacteria were tested. The antibacterial activity was determined by measuring the diameter of zone of inhibition (mm) produced after incubation. The phytoconstituents present in fresh and dry flowers of C. pulcherrima were found to possess potent antibacterial activity. It was found that the ethanol extract of dry flower of C.pulcherrima exhibited maximum activity against Bacillus subtilis (25mm) bacteria. Chloroform and ethanol extracts of dry flowers exhibited moderate activity against Bacillus subtilis and Klebsiella pneumoniae (22mm). The minimum inhibitory concentration ranged between 2.5mg/mL and 15mg/mL depending on microorganism and various extract. The results reported in the present work shows evidence that the extracts of C.pulcherrima possess potent antibacterial activity against tested pathogenic organisms.