Abstract

ANTIBACTERIAL SCREENING OF AQUEOUS EXTRACTS OF SOME MEDICINAL PLANT AND THEIR FRACTIONS USED AS ANTIDIARRHEAL AGENTS IN KINSHASA-DEMOCRATIC REPUBLIC OF CONGO

Cimanga Kanyanga R.*, Makila Bool-Miting F., Tona Lutete G., Kambu Kabangu O., Vlietinck A. J., Pieters L.

ABSTRACT

Thirteen aqueous extracts (decoctions) used as antidiarrheal in Kinshasa, Democratic Republic of Congo and their forty two fractions were submitted to an evaluation for their potential antibacterial properties against isolated pathogenes bacteria implicated in diarrhea. Results indicated that five extracts including those from Carica papaya root, Hensia pulchella leaf, Morinda morindoides leaf, Psidium guayava leaf, Tithonia diversifolia leaf as well as their respective ethylacetate fractions rich in flavonoids inhibited the growth of all tested bacteria with minimum inhibitory and bactericidal concentrations ranging from 15.62 to 62.50 μg/ml (good activity). Aqueous extracts from other selected medicinal plants exhibited a combined level of activity as good (MIC and MBC < 100 μg/ml), moderate (125 < MIC and MBC < 250 μg/ml and weak (250 < MIC and MBC < 500 μg/ml) or were inactive (MIC and MBC > 500 μg/ml) against some selected bacteria according to the case. These results can partly justify and support the tradition use of these medicinal plants for
the preparation of remedies used for the treatment of diarrhea of bacterial origin.

Keywords: Medicinal plants, aqueous extracts, fractions, diarrhea, antibacterial activity.