STUDY OF THE ANTIMICROBIAL ACTIVITY OF ROSEMARY (ROSMARINUS OFFICINALIS L.) CALLUS EXTRACT AND SELECTED TYPES OF ANTIBIOTICS AGAINST SOME BACTERIAL SPECIES

Abstract

The chemical analysis of rosemary (Rosmarinus officinalis L.) callus ethanol extract was carried out using gas chromatography-mass spectrometry (GC-MS). The most abundant compounds of callus ethanol extract were, qunoline alkaloid, phytol, eucalyptol, camphor, borneol, verbenone and bornyl acetate. Escherichia coli and Salmonella typhi showed resistance to Rifampicin and Erythromycin, while they were sensitive to other antibiotics. On the other hand, Staphylococcus aureus showed moderate sensitivity to antibiotics used. Standard compounds have an activity at range of 0.7 to 2.5 cm, Rosmarinic acid and carnosic acid were found to be the most effective antimicrobial compounds against bacterial species involved in this study. The study indicates that higher concentrations of the extract were required to inhibit gram-negative bacteria. It was found that 320 ul/ml of callus extract was enough to inhibit Escherishia coli, while 640 ul/ml of extract was required to inhibit Salmonella typhi. Callus ethanol extract was more active against gram-positive bacteria; Staphyllococcus aureus. Their growth was inhibited at 60 ul/ml of the extract. Thus, the callus extract having a broad spectrum activity against gram positive and gram negative bacteria.