US EPA

1449063 

Journal Article 

Antibacterial activities of the extracts, fractions and compounds from Dioscorea bulbifera 

Kuete, V; Betrandteponno, R; Mbaveng, AT; Tapondjou, LA; Meyer, JJM; Barboni, L; Lall, N 

2012 

Yes 

BMC Complementary and Alternative Medicine
ISSN: 1472-6882
EISSN: 14726882 

12 

23176193 

10.1186/1472-6882-12-228 

WOS:000312726500001 

Background: Dioscorea bulbifera is an African medicinal
plant used to treat microbial infections. In the present study, the methanol extract, fractions
(DBB1 and DBB2) and six compounds isolated from the bulbils of D. bulbifera, namely
bafoudiosbulbins A (1), B (2), C (3), F (4), G (5) and 2,7-dihydroxy-4-methoxyphenanthrene (6),
were tested for their antimicrobial activities against Mycobacteria and Gram-negative bacteria
involving multidrug resistant (MDR) phenotypes expressing active efflux pumps. Methods: The
microplate alamar blue assay (MABA) and the broth microdilution methods were used to determine
the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of the
above samples. Results: The results of the MIC determinations indicated that when tested alone,
the crude extract, fractions DBB1 and DBB2 as well as compounds 2 to 5 were able to prevent the
growth of all the fifteen studied microorganisms, within the concentration range of 8 to 256 mu
g/mL. The lowest MIC value for the methanol extract and fractions (16 mu g/mL) was obtained with
DBB1 and DBB2 on E, coli AG100A and DBB2 on Mycobacterium tuberculosis MTCS2. The lowest value
for individual compounds (8 mu g/mL) was recorded with compound 3 on M. smegmatis and M.
tuberculosis ATCC and MTCS2 strains respectively. The activity of the samples on many MDR
bacteria such as Enterobacter aerogenes EA289, CM64, Klebsiella pneumoniae KP63 and Pseudomonas
aeruginosa PA124 was better than that of chloramphenicol. When tested in the presence of the
efflux pump inhibitor against MDR Gram-negative bacteria, the activity of most of the samples
increased. MBC values not greater than 512 mu g/mL were recorded on all studied microorganisms
with fraction DBB2 and compounds 2 to 5. Conclusions: The overall results of the present
investigation provided evidence that the crude extract D. bulbifera as well as some of the
compounds and mostly compounds 3 could be considered as potential antimicrobial drugs to fight
against MDR bacteria. 

Diterpenoids; Antimycobacterial; Antibacterial; Dioscorea bulbifera; Dioscoreaceae