Investigation of the antimicrobial potentials of some phytochemical extracts of leaf and stem bark of Berlinia grandiflora (Leguminoceae) Caesalpinioidae against pathogenic bacteria

IntroductionBerlinia comprises about 20 species which are confinedto tropical Africa with almost all the species found inWest and Central Africa (Hutchison and Dalziel, 1963).Berlinia grandiflora is widespread in Guinea, Mali,Nigeria, Central Africa and Democratic Republic ofCongo (Hutchison and Dalziel, 1963). It is a forest treethat is sometimes planted as ornamental tree and shadetree in villages and coffee plantations. It is occasionallybrowsed by livestock especially sheep and goats. TheIgbos of South Eastern Nigeria refers to it in their locallanguages as abaa, dokar, rafi, and ububa while theYorubas of the South West Nigeria refer to it as apado.Its bark sap is applied to sores and wounds, and barkdecoctions are administered to treat haemorrhoids andliver complaints (Gill, 1992). The bark is used to easelabour during child birth and gastrointestinal disorders.A decoction of the leafy twigs is used as febrifuge andantiemetic while leafy decoctions are taken as tonic(Gill, 1992). Reports of its biological activities are scantyand include analgesic activity of stem bark extract(Asuzu et al, 1993), antihelminthic activity of stem bark(Enwerem et al, 2001), antihelminthic activity of stembark and its active principle, betulinic acid (Enwerem etal, 2001).In South Eastern Nigeria, the leaf and the stem barkextracts of the plant are used by traditional herbalists totreat microbial infections. However, this ethnomedicinaluse of the plant parts has not been validatedscientifically. This study investigated the antimicrobialpotential of the aqueous, methanol and butanol extractsof the leaves and stem bark against pathogenic bacteriaas part of our evaluation of its antimicrobial activity