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

Abstract

Introduction
Berlinia comprises about 20 species which are confined
to tropical Africa with almost all the species found in
West and Central Africa (Hutchison and Dalziel, 1963).
Berlinia grandiflora is widespread in Guinea, Mali,
Nigeria, Central Africa and Democratic Republic of
Congo (Hutchison and Dalziel, 1963). It is a forest tree
that is sometimes planted as ornamental tree and shade
tree in villages and coffee plantations. It is occasionally
browsed by livestock especially sheep and goats. The
Igbos of South Eastern Nigeria refers to it in their local
languages as abaa, dokar, rafi, and ububa while the
Yorubas of the South West Nigeria refer to it as apado.
Its bark sap is applied to sores and wounds, and bark
decoctions are administered to treat haemorrhoids and
liver complaints (Gill, 1992). The bark is used to ease
labour during child birth and gastrointestinal disorders.
A decoction of the leafy twigs is used as febrifuge and
antiemetic while leafy decoctions are taken as tonic
(Gill, 1992). Reports of its biological activities are scanty
and include analgesic activity of stem bark extract
(Asuzu et al, 1993), antihelminthic activity of stem bark
(Enwerem et al, 2001), antihelminthic activity of stem
bark and its active principle, betulinic acid (Enwerem et
al, 2001).
In South Eastern Nigeria, the leaf and the stem bark
extracts of the plant are used by traditional herbalists to
treat microbial infections. However, this ethnomedicinal
use of the plant parts has not been validated
scientifically. This study investigated the antimicrobial
potential of the aqueous, methanol and butanol extracts
of the leaves and stem bark against pathogenic bacteria
as part of our evaluation of its antimicrobial activity.