Abstract

SPASMOLYTIC ACTIVITY OF FLAVONOID EXTRACTS FROM SOME MEDICINAL PLANTS USED AS ANTIDIARRHEAL AGENTS IN TRADITIONAL MEDICINE IN KINSHASA- DRCONGO

Cimanga K. R.*, Gatera G. S., Tona L. G., Kambu K. O., Vlietinck A. J. and Pieters L.

ABSTRACT

Seventheen flavonoid extracts from some medicinal plants used as antidiarrheal agents were evaluated for their potential spasmolytic activity at concentrations from 10-1 to 6.10-1 mg/ml in organ bath against acetylcholine (ACh) and depolarizing solution rich in KCl (DSR-KCl)-induced contrations on isolated guinea-pig ileum. Resulted indicated that 8 (47.05%) flavonoid extracts inhibited ACh and DSR KCl-induced contractions of isolated guinea-pig ileum more than 60%. The most active samples produced more than 65% and more than 60% inhibition of ACh and DSR KCl-induced contractions of isolated guinea-pig ileum respectively at a tested concentration from 1.6.10-1 to 2.10-1 mg/ml. They included flavonoid extracts from Alcornea cordifolia leaves (73.90 ± 0.06 and 68.36 ±0.03 %), Ceiba pentandra stem bark (66.30±0.02 and 63.25±0.05%), Euphorbia hirta whole plant (75.52 ± 0.01 and 72.15 ± 0.05%), Garcinia kola stem bark (75.20 ± 0.02 and 66.35 0.10 %), Harugana madagascariensis stem bark (66.00±0.10 and 55.21±0.13), Morinda morindoides leaves (78.81 ± 0.01 and 75.65 ± 0.03%), Psidium guajava (71.75 ± 0.04 and 68.54 ± 0.02 %) and Tithonia diversifolia leaves. (71.25±0.06 and 67.25±0.03%). A group of 5 (29.41%) flavonoid extracts including those from Cassia siamea, and Pentaclethra macrophylla stem bark, Jatrpha curcas, Nauclea latifolia and Phytolaca dodecandra leaves inhibited ACh and DSR KCl-induced contractions on guinea-pig ileum with more than 50% but less than 60% at tested concentration of 2.10-1 mg/ml. 3 (17.64%) flavonoid extracts from Bridelia ferruginea and Crossopterix febrifuga leaves, an Hymenocardia acida stem bark produced more than 50% inhibition of ACh and less than 50% inhibition against DSR KCl-induced contractions on isolated organ. The 1 (5.88%) flavonoid extract from Mangifera indica stem bark produced less than 50% inhibition of contractions induced by both agonists on the isolated organ (16-30% inhibition). These reported results demonstrated that more selected flavonoid extracts possess interesting spasmolytic activity which can be partly considered as responsible of the spasmolytic activity of these medicinal plant extracts and explain their traditional use for the treatment of diarrhea in traditional medicine in Kinshasa-Democratic Republic of Congo and other African countries.

Keywords: Medicinal plants, flavonoid extracts, spasmolytic activity, diarrhea.