| Resume |
The precipitation and coloration reactions implemented in this
study revealed in the leaves of E. citriodora (Myrtaceae) of Benin the presence of
polyphenols, anthocyanins, flavonoids, saponins, tannins, mucilages,
anthraquinones, leucoanthocyanins, cardiac glycosides, coumarins, proteins, sterols
and triterpenes. The essential oil from the leaves of this plant was extracted with a
yield of 3% and then analyzed by GC/MS. Nine compounds, representing 94.46%
of the chemical composition of the oil, were identified, three among them being
majority: citronellal (65.45%), citronellol (13.5%) and isopulegol (10.33%). The
contents of polyphenolic compounds of ethanolic and hydroethanolic extracts were
respectively 4.52 mg EAG.g-1 and 4.38 mg EAGg-1 for total polyphenols, 78.76 mg
ECg-1 and 81.56 mg ECg-1 for total flavonoids and 62.62 mg ECg-1 and 67.09 mg
ECg-1 for condensed tannins. The radical scavenging activity of hydroethanolic
extract (IC50=0.23 mgmL-1) was more pronounced than that of ethanolic extract
(IC50=0.42 mgmL-1) and essential oil (IC50=0.9 mgmL-1). Regarding antimicrobial
activity, Staphylococcus aureus and Candida albicans were sensitive to
hydroethanolic extract of E. citriodora leaves while Escherichia coli developed
resistance against this extract. As for the essential oil extracted from the leaves of
Eucalyptus citriodora it showed fungicidal activity against Candida albicans and
bacteriostatic with Escherichia coli and Staphylococcus aureus |