Abstract:
Pericarp of the fruit of Garcinia mangostana L is used for the treatment of skin
infections, wounds and diarrhea in indigenous medicine of Thailand, India, Sri
Lanka and Myanmar. In the present study, the inhibitory effect of extracts of
pericarp ofGarcinia mangostana on bacterial growth was investigated.
An inhibitory activity was exhibited by methanolic extract against Gram-positive
bacteria tested (Bacillus subtilis., Staphylococcus aureus. and Streptococcus
faecalis) whilst no inhibitory effect was observed against Gram -negative bacteria
such as Escherichia coli, Proteus mirabilis and Pseudomonas aeruginosa.
Minimum inhibitory concentration (MIC) was determined using serially diluted
extract with methanol on nutrient agar. After 24 hours of incubation at room
temperature, the lowest concentration of the extract which inhibited the visible
bacterial growth was recorded as MIC. The MIC of the extract was 0.0005 glml
against Bacillus subtilis and Staphylococcus aureus while 0.005g1ml against
Streptococcus faecalis.
Crude extract was fractionated with ether and ethyl acetate successively to obtain
ether-soluble and ethy I acetate - soluble phenolics respectively. These two fractions
were found to possess inhibitory effect on growth of Bacillus subtilis.,
Staphylococcus aureus. and Streptococcus faecalis. Chromatographic analysis of
the two fractions showed the presence of several phenolic compounds.
