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The aim of this investigation was to simplify extracts to facilitate the isolation
of antibacterial compounds from the complex mixture of chemicals in the plant
by using different extractants. Intact dried leaves were extracted with acetone
and 1% aqueous sodium bicarbonate and ground leaves were extracted by hexane,
carbon tetrachloride, di-isopropylether, ethyl ether, methylene dichloride,
tetrahydrofuran, acetone, ethanol, ethyl acetate, methanol and water. TLC was
used to determine chemical composition and antibacterial activity of extracts
was determined by a microplate serial dilution method. The different solvents
extracted from 2.6 to 17.4% of the dry weight. Methanol, methylene dichloride
and tetrahydrofuran extracted the most components. The chemical composition
of the non-polar components of the different extracts were remarkably similar.
The minimum inhibitory concentration for the different extractants varied from
0.01 to 1.25mg/ml with the four test organisms used (Staphylococcus aureus,
Pseudomonas aeruginosa, Escherichia coli and Enterococcus faecalis). The extracts
had similar activity towards Gram-negative and Gram-positive bacteria. Di-isopropyl
ether, ethanol, ethyl ether, acetone and ethyl acetate extracted high antibacterial
activity with a lower quantity of other non-active compounds and could be useful
for isolating bioactive compounds.

South African Journal of Botany 2002, 68: 62–67