KALYANI JATOTH, SACHIN GAIKWAD, SWATHI VISLAWATH AND SANDEEPTA BURGULA
Abstract
In the present study, the Anti-bacterial activity of methanolic flower extracts of a Himalayan herb, Saussurea gossypiphora has been studied. The antibacterial activity of S. gossypiphora extracts was examined against Gram-positive and Gram-negative bacteria. The extracts inhibited Gram-positive bacteria, especially Staphylococcus epidermidis and Bacillus cereus. Hence these two strains were selected for further studies. Minimum Inhibitory Concentration of the extracts was assessed and observed to be 100 mg/ml for S. epidermidis and 125 mg/ml for B.cereus. Time-kill kinetic studies indicated bactericidal effect of the extract on both strains. Scanning electron microscopy of the strains when treated with the extracts revealed morphological changes in the cells i.e., shrinkage of cells, damage and disruption of cell wall and cell membrane. Further analysis revealed leakage of DNA and proteins from the bacteria upon treatment with the extracts. In conclusion, S. gossypiphora extracts have significant bactericidal activity against Gram-positive bacteria which results in disruption of the microbial membrane, leading to the leakage of intracellular material that results in microbial death. Thus the extracts can be further explored for their antimicrobial activity.