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The practice of traditional medicine by plants is very popular among African populations including those of the Department of Agboville (South-East of Côte d'Ivoire) against various diseases, particularly malaria. The objective of this study is to verify by subacute toxicity the safety of the aqueous and ethanolic extracts of twelve medicinal plants from this Department in order to justify their traditional uses. The methodology used is OECD guideline 423, which is to determine in which dose range a substance should be considered lethal. Thus after the distribution of the female rats in several lots of 3, we gave them different doses (5, 50, 300, 2000 and 5000 mg/kg per body weight (PC)) of our aqueous and ethanolic extracts. The results obtained at the end of the experiment give a lethal dose 50 (LD 50 ) estimated to be greater than 5000 mg/kg PC. This means that the extracts of the 12 plants administered as a single dose by oral see result in a relatively low toxicity even if we have noticed some slight signs of intoxication at the limit dose of 5000 mg/kg PC.At the end of this study, the estimated LD 50 greater than 5000 mg/kg PC makes it possible to affirm the safety of twelve plants used by the traditional health practitioners of the Department of Agboville (South-East of Côte d'Ivoire). ).

Parasitic biobank of Plasmodium falciparum is almost germinal in Côte d’Ivoire. However, several high-level research topics on this parasite involve the taking into account of nature isolates but also chemo-sensitive or resistant reference strains for a better validation of results. In addition, acquisition of these reference strains is still arduous for laboratories in developing countries due to complexity of administrative procedures. For those reasons, this study aimed in to combine several procedures into a consolidated one in order to enhance the multiplication of P. falciparum reference strains. Continuous culture of plasmodial strains was based on the Trager and Jensen procedures. The CELL culture protocols used are those of the Swiss TPH described by Sergio Wittlin; the “Growing Plasmodium falciparum cultures at high parasitemia” and the “Stockholm sorbitol method” of Methods in Malaria Research-6th edition 2013; and the INV-01 and INV-02 procedures of the Worldwide Antimalarial Resistance Network (WWARN). Reference Plasmodium falciparum strains NF54 sensitive to chloroquine (CQs) and K1 resistant to chloroquine (CQr) were received from the Swiss Tropical Institute and Public Health (Swiss TPH). The CQs NF54 strain reacted more quickly to the protocol unlike the CQr K1 strain. Parasitic densities (DP) obtained with NF54 strain were ranged from 0.4% at day zero (D0) to 11.4% at day eight (D8). Strain K1 finally adapted successfully after one month of follow-up. Related DPs ranged from less than 0.1% to more than 20% in just three growth cycles after adaptation. A joint protocol (from this work) called “CRLP-SwissTPH-Pasteur_001” is available and allows to efficiently multiply reference strains NF54 and K1. It is planned to spread out the tests to other plasmodial strains as well as to wild isolates in order to standardize this procedure.

Malaria disease is a pathology which occurs as a result of the oxidative stress. Three plants of the Ivorian pharmacopoeia are particularly used in the traditional medicine for the treatment of malaria in Côte d'Ivoire. They are Cochlospermum planchonii (Placo), Pericopsis laxiflora (Laper) and Harungana madagascariensis (Madhar).The objective of this study was to evaluate the in vitro antioxidant activity of the aqueous and methanolic extracts of three medicinal plants of Côte d'Ivoire. The quantitative measurement of total flavonoids gave the following results: Laper (560.80 mg QE/g ± 7.40), Madhar (352.50 mg QE/g ± 9.46) and Placo (314.20 mg QE/g ± 4.41). The total polyphenols were more concentrated in Laper (262.50 mg GAE/g ± 9.47) and Placo (203.20 mg GAE/g ± 2.21). Noticeable zinc content was found in Laper (13.56 ppm) and Placo (11.40 ppm) against 3.43 ppm in Madhar. The radical scavenging activity by 2,2-diphenyl-1-picryl hydrazyl (DPPH) and antiradical power measurement by ABTS (2,2' azino bis-3-ethylbenzothiazoline-6-sulphonic acid) assay have showed good activity for Laper (IC 50 = 7.50 µg/mL) and placo (IC 50 = 8.01 µg/mL). The standard antioxidant compound (quercetin) gave an IC 50 = 4.00 µg/mL. This study suggested that the high content of total flavonoids, total phenols and minerals in these plants could partly justify the therapeutic use of at least two of the three plants.