Screening of Petroleum ether, Chloroform, Ethyl acetate, Ethanol and Water Extracts of Medicinal Plant, Avicennia marina for Antibacterial Activity against Antibiotic Resistant Bacteria Species, Staphylococcus and Proteus

Abstract

The secondary metabolites of the young leaves of Avicennia marina were obtained by sequential Soxhlet extracts with petroleum ether, chloroform, ethyl acetate, ethanol and water as solvents. Antibacterial activity against antibiotic resistance and pathogenic bacterial species of Staphylococcus and Proteus was screened by agar diffusion technique and paper disk method. The extracts exhibited different degree of growth inhibition against tested bacterial strains. Ethyl acetate extract exhibited the highest antibacterial activity while water extract did not show any growth inhibition. The extracts of A. marina when purified with activated charcoal showed more inhibition than the untreated extracts. Components of young leaf extracts were separated by Thin Layer Chromatography (TLC). The results of TLC analysis of petroleum ether, chloroform, and ethyl acetate and ethanol Soxhlet extracts of A. marina may be a mixture of 4, 8, 4 and 4 respectively. The results of the two dimensional TLC analysis for the chloroform extract isolated from the Soxhlet plant extracts of A. marina may be a mixture of twenty components. Chloroform, ethyl acetate and ethanol extracts were fractionated using column chromatography and obtained fourteen, seven and seven fractions respectively. Phytochemical screening revealed that young leaf of A. marina contained alkaloids, steroids. Phytochemical screening of Soxhlet extracts of chloroform contained alkaloids and steroids/triterpenoids. Ethyl acetate and ethanol extract contained steroids/ triterpenoids and alkaloids respectively. Chemical tests revealed that fractions obtained from column chromatography of chloroform, ethyl acetate, ethanol extracts contained carbonyl groups and chloroform extract contained phenolic groups.