dc.description.abstract | Macaranga species are traditionally used for the
treatment and management of coughing, fungal infection, and wounds.
In this study, the phytochemical screening and antibacterial activities
of nine crude extracts from Macaranga conglomerata, Macaranga
kilimandscharica and Macaranga capensis were determined against 13
bacterial strains expressing multi-drug resistance (MDR) phenotypes.
Methods: Phytochemical screening of the extracts were carried out
according to the standard methods, while the iodonitrotetrazolium chloride
(INT) colorimetric assay was used to determine the minimal inhibitory
concentration (MIC) and minimal bactericidal concentration (MBC) of the
plants extracts. Results: Flavonoids, terpenoids, saponins and coumarins
were the major secondary metabolites found in all the plant extracts. The
results of antibacterial studies revealed that all the plant extracts displayed
good activities with MIC values ranging from 4 – 128 μg/mL against the
tested micro-organisms. Most of the extracts exhibited a bactericidal effect
against E. coli, E. aerogenes, K. pneumoniae, P. stuartii, P. aeruginosa, and
S. aureus with MBC/MIC ratio ≤ 4. In the presence of efflux pump inhibitor
(PaβN), the inhibition potency of all the crude extracts against the tested
bacterial strains were substantially enhanced. It is worth noting that the
activities of MKL, MCL, and MCR towards P. stuartii (NEA16), E. aerogenes
(ATCC13048), and K. pneumoniae (KP55), respectively were improved by
more than 8-fold in the presence of PAβN. Conclusion: The findings of
this study indicated the possibility of using all the tested plant extracts
as a source of therapeutic agents in the fight against multi-drug resistant
bacteria. | en_US |