Abstract

Casuarina equisetifolia (Casuarinaceae) is a plant that is used in folk medicine for the treatment of astringent, in diarrhea, cough, ulcers, toothache, lotion for swelling and diabetes. To evaluate the scientific basis for the use of the plant, the antimicrobial activities of leaves extract was investigated against 7 medically important bacterial strains, namelyBacillus subtilis, methicillin-resistant Staphylococcus aureus (MRSA), Micrococcus,Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumoniae and 4 fungi. The antibacterial activity of aqueous and organic solvents was determined by agar well diffusion method. The most pronounced effect was shown by the methanol extract. The most susceptible bacteria were S. aureus, followed by K. pneumoniae, while the most resistant bacteria was B. subtilis followed by Micrococcus. The antifungal activity of aqueous and organic solvents was also determining. The most pronounced effect was shown by ethanolic. The most susceptible fungi were Aspergillus flavus while the most resistant fungi were Candida albicans. The high performance liquid chromatography (HPLC) analysisindicated the presence of 8 phenolic compounds as major active constituent (gallic, protocatioic, chlorogenic, syringic, p.hydroxy benzoic, p.coumaric, vanillic and salicylic acid). Result obtained indicated variable difference in concentration of the compounds in C. equisetifolia leaves extract. Results of HPLC showed gallic, salicylic and protocatioic in high concentration of 19.18, 11.57 and 6.84 µg/g, respectively. The concentration of other phenolic compounds ranged from 1.63 to 4.70 µg/g. The least concentration was chlorogenic with 1.63 µg/g.

Key words: Casuarina equisetifolia, antibacterial, antifungal, phytochemical constituents, crude extract