Phytochemical Study and Anthelmintic Activity of Nine Congolese Medicinal Plants

Background: Despite advances in hygiene and preventive medicine, parasitic diseases, particularly digestive parasitosis, remain a public health problem in tropical countries. Elaborate the ethnobotanical survey carried out in Brazzaville - Congo, 21 plants (divided into 20 families, 20 genera) were identified, among them 9 were selected for this study. These were: Ageratum conyzoides (L.) L., Rauvolfia mannii Stapf, Aloe buettneri A. Berger, Garcinia kola Heckel, Piper guineense Schumach & Thonn., Aframomum alboviolaceum (Ridl.) K. Schum., Plagiostyles africana (Mull .Arg.) Prain, Morinda lucida Benth, Cogniauxia podoleana Baill. Materials and Methods: The in vitro evaluation of the anthelmintic activity of the aqueous extracts of these 9 plants was determined at concentrations of 10, 25 and 50 mg/mL against Lumbricus terrestris used as animal support in comparison to the Mebendazole (20 mg/mL). The phytochemical screening realized by TLC to detect phytochemical families in plant, also, the antioxidant potential with DPPH radical was determined by UV-Visible spectrophometry in comparison to the Vitamin C. Results: Thus, P. guineense, A. conyzoides and A. alboviolaceum are those which presented significant vermicidal effect, after Mebendazole. Phytochemical screening into TLC revealed the co-presence of alkaloids, coumarins, flavonoids, tannins, sterols and terpenes.The antioxidant potential of the aqueous extracts of these different plants in comparison to vitamin C, has shown that the species A. Buettineri and A. alboviolaceum presented the best potential compared to 7 other species studied, with the  concentration  needed to  reduce 50% of the DPPH radical (CR50)  respectively 0.096 mg/mL for A. Buettineri, 0.098 mg/mL for A. alboviolaceum Berger and 0.015 mg/mL for vitamin C. Conclusion: There is modern drugs against intestinal worms, it is necessary to identify the plants with anthelmintic activity, to determine phytochemical compounds that would be responsible for their use by traditional healers to treat the intestinal parasitosis.