Abstract

ASSESSMENT OF ANTIBACTERIAL, ANTIAMOEBIC AND SPASMOLYTIC ACTIVITIES OF THE AQUEUSOUS EXTRACTS, THE ETHANOL EXTRACTS AND THEIRS RESPECTIVE FRACTIONS FROM THE SEEDS OF RIPE AND UNRIPE FRUITS OF CARICA PAPAYA L. (CARICACEAE) COLLECTED IN KINSHASA, DEMOCRATIC

Cimanga Kanyanga R.*., Mabanzolele Makanda, M. , Kapanga Nai Nai, L., Tona Lutete, G., Kambu Kabangu O. Apers, S., Vlietinck, A.J., Pieters L.

ABSTRACT

The aqueous extracts, the ethanol extracts and their respective fractions of the seeds from ripe and unripe fruits of Carica papaya were screened for their putative antibacterial, antiamoebic and antispasmodic activities. Results indicate that the aqueous extracts, the ethanol extracts and their respective fractions from the seeds of both states of the fruit exhibited antibacterial activity at different extents. Samples of the seeds from ripe fruits showed higher activity with minimum inhibitory and minimum bactericidal concentrations ranged from 7.81 to 250 μg/ml compared to samples from the seeds of unripe fruits (15.62 to 500 μg/ml) against the majority of selected bacteria. The evaluation of the antiamoebic activity against Entamoeba histolytica revealed that the aqueous extracts, the ethanol extracts and their fractions of seeds from ripe and unripe fruits were able to inhibit the growth of this parasite with minimum amoebicidal concentrations (MAC) less than 20 μg/ml. A significant and gradual decrease of vital parasites in the presence of all tested samples was daily observed from Day 1 to Day 6 while in negative control tubes, a significant increase was recorded. The most active samples were the aqueous, ethanol and total alkaloid extracts from the seeds of ripe fruits with 1 < MAC (minimal amoebicidal concentration) < 5 μg/ml and the ethanol extract from the seeds of unripe fruits with MAC value of 3.12 μg/ml. In antispasmodic activity testing, the aqueous extracts, the ethanol extracts and their respective fractions from both seed fruits state produced more than 60% inhibition of contractions of guinea-pig ileum induced by acetylcholine and depolarized solution rich in KCl at the tested concentration of 40 μg/ml. The most active samples were the aqueous and alkaloid extracts, and ethanol extracts from both seeds states showing more than 70% and 80% inhibition respectively, the ethylacetate fraction from the partition of the ethanol extract of seeds from ripe fruits producing more than 70% inhibition of contractions of guinea pig-ileum induced by both agonists while the same fraction of the seeds from unripe fruits produced more than 65% inhibition, but less than 70%. These reported results can justify and support the use of mainly the seeds from the ripe fruits of C. papaya in traditional medicine for the treating of diarrhea since they would act by their antibacterial, antiamoebic and spasmolytic activities proven in the present study.

Keywords: Carica papaya, Caricaceae, seeds, ripe and unripe fruits, antibacterial, antiamoebic and spasmolytic activities, diarrhea.