10.22376/ijpbs.2019.10.1.p1-12 Volume 10 Issue 4 2019 (October-December) Malaria remains a public health problem because of the consequences it has. Existing treatments are becoming increasingly ineffective. It is therefore urgent to find new antimalarial drugs. Medicinal plants appear to be an important source to explore. Thus, this study on lessThan i greaterThan Hoslundia opposita lessThan /i greaterThan will provide a scientific basis for its traditional use. Indeed, lessThan i greaterThan Hoslundia opposita lessThan /i greaterThan has always been used in traditional medicine by naturopaths for the treatment of malaria. This study is part of a vast program of extensive medicinal plant science. The objective of this work is to evaluate lessThan i greaterThan in vitro lessThan /i greaterThan chemosensitivity of the aqueous and hydroethanolic extracts of lessThan i greaterThan Hoslundia opposita lessThan /i greaterThan (Lamiaceae) leaves on lessThan i greaterThan Plasmodium falciparum lessThan /i greaterThan by maturation tests and RSA lessThan i greaterThan ex vivo lessThan /i greaterThan . The maturation test of the different extracts from the five clinical isolates of lessThan i greaterThan Plasmodium falciparum lessThan /i greaterThan showed antimalarial activity, with a promising effect of the aqueous extract (IC lessThan sub greaterThan 50 lessThan /sub greaterThan = 12.66 μg/mL). The two extracts obtained by hydroethanolic partition have a moderate effect with IC lessThan sub greaterThan 50 lessThan /sub greaterThan between 15 and 50 μg/mL. The results of the lessThan i greaterThan RSA lessThan /i greaterThan lessThan i greaterThan ex vivo lessThan /i greaterThan test confirmed those of the maturation test with a survival percentage of approximately 50% of parasites (i,e 50% inhibition), as the parasites were exposed to the IC lessThan sub greaterThan 50 lessThan /sub greaterThan of the various cells extracts used for the maturation test. These results make lessThan i greaterThan Hoslundia opposita lessThan /i greaterThan a potential resource in the search for antimalarial molecules. OBOU CONSTANTIN OKOU, SYLVAIN BEOUROU, ALLOH ALBERT GNONDJUI, EVE VICTOIRE AKPOUE AND ALLICO JOSEPH DJAMAN Extracts, Hoslundia opposita, Chemosensitivity, Plasmodium falciparum 97-104