Validation of use of a traditional remedy from Bridelia grandis (Pierre ex Hutch) stem bark against oral Streptococci.
OBJECTIVE
Bridelia grandis (Pierre ex Hutch) (Euphorbiaceae) is a medicinal plant traditionally used in Cameroon by pygmies Baka as a remedy for oral cavity affection. Bioassay-guided stem bark extracts were investigated for their in vitro antimicrobial properties as well as their phytochemical constituents.


METHODS
The first extraction was carried out according to the traditional use. Further extractions were carried out with solvents of different polarity such as methanol (MeOH), ethyl acetate (EtOAc) and mixtures of MeOH-H2O. The antimicrobial activity of the extracts against oral Streptococci was evaluated on the basis of the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) by the macrodilution method; the bacterial surface hydrophobicity was also evaluated.


RESULTS
Water, methanol and mixtures methanol-water extracts, exhibited antibacterial activity with MIC between 0.5 and 2mg/ml justifying the traditional use of Bridelia grandis stem bark for oral cavity affection. Preliminary phytochemical analysis was performed on the most active extract (methanol) using appropriate tests and well established analytical screening methods, such as TLC and RP-HPLC/DAD.


CONCLUSIONS
The data obtained indicate that tannins constitute the chemical family responsible for the biological activity.
Ngueyem
T A
TA
Department of Pharmaceutical Chemistry, University of Pavia, Pavia, Italy.
Brusotti
G
G
Marrubini
G
G
Grisoli
P
P
Dacarro
C
C
Vidari
G
G
Finzi
P Vita
PV
Caccialanza
G
G
D000900:Anti-Bacterial Agents / Q000302:isolation & purification / Q000494:pharmacology*; D002163:Cameroon; D019665:Euphorbiaceae / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D016488:Medicine, African Traditional; D008826:Microbial Sensitivity Tests; D024301:Plant Bark; D010936:Plant Extracts / Q000494:pharmacology*; D012997:Solvents / Q000737:chemistry; D013291:Streptococcus / Q000187:drug effects*; D013634:Tannins / Q000302:isolation & purification / Q000494:pharmacology
D000900:Anti-Bacterial Agents; D010936:Plant Extracts; D012997:Solvents; D013634:Tannins