Organic acid content and Antimicrobial Properties of Eleiodoxa conferta Extracts at Different Maturity Stages

Eleiodoxa conferta water extracts at different maturity stages were shown to
contain three types of organic acid which are oxalic, ascorbic and malic acids
by HPLC analysis. The content of oxalic acid concentration was the highest at
young stage (1.33 gml
-1
) followed by mature stage (1.26 gml-1
) and ripe stage at
1.23 gml-1
. Malic acid content decreased during ripening from 1.38 gml-1
to 1.07
gml-1
. The concentration of ascorbic acid remained constants during the fruit
ripening. When antimicrobial activity of the extract was tested against several
bacteria it was observed that the activity decreased as the fruit ripen. Highest
diameter of inhibition zone was recorded against Escherichia coli by the young
fruit extract at 15.3 mm. MIC of 0.063 gml-1
exhibit by the young fruit extract
was helpful in controlling the growth of Gram negative bacteria, E. coli.
However, 0.063 gml-1
concentration of extract from mature fruit is shown to
regulate the growth of Gram positive bacteria, Staphylococus aureus.