an investigation into the antibacterial activities of medicinal plants ...

(1.30 x10 11 ) in the plant extract suspension in comparison to the bacteria control
(1.34 x 10 11 ). Further testing is needed in the plant extract concentrations and the
inhibition of the bacteria.
The antibacterial activity of the medicinal plant extracts and traditional preparations
especially M. major and L. leonurus supports the traditional uses of these plants for
treating infected skin lesions.
The aim of this study was achieved by proving the in vitro antibacterial activities of
the indigenous plants used traditionally for bacterial wound infections. The objectives
of screening indigenous plants for antibacterial activity and reporting on the MIC of
the plant extracts were also achieved. This study may contribute to the increased
scientific investigation done on indigenous medicinal plants used traditionally in the
different parts of South Africa.
The different chemical composition of medicinal plants and extraction solvent
characteristics influenced the amount of plant material extracted from medicinal
plants. In this study M. major yielded the highest average concentration of plant
material extracted and B. frutescence yielded the lowest concentration of plant
material following the different extractions. The difference in the plant concentration
yield for the two plants may be ascribed to the plant processing and surface area of
plant material presented for extraction.
The acetone extraction solvent yielded the highest average concentration of plant
material extracted and the aqueous solvent produced the lowest average
concentration of plant material extracted from medicinal plants. Similar findings
were displayed in previous investigations using these solvents for plant extraction
(Martini & Eloff, 1998).
Consequently the acetone extract of M. major yielded the highest concentration of
plant material extracted in comparison to the other solvents and medicinal plants.
The plant extracts of M. major followed by L. leonurus gave promising antibacterial
activity against a wide range of the bacteria that was tested. Purification of the B.
frutescens and Z. aethiopica plant extracts may yield more potent extracts with
higher antibacterial activity.
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