Abstract:
BACKGROUND : This study evaluated the antibacterial activity of some plants used in folklore medicine to treat
diarrhoea in the Eastern Cape Province, South Africa.
METHODS : The acetone extracts of Acacia mearnsii De Wild., Aloe arborescens Mill., A. striata Haw., Cyathula uncinulata
(Schrad.) Schinz, Eucomis autumnalis (Mill.) Chitt., E. comosa (Houtt.) Wehrh., Hermbstaedtia odorata (Burch. ex
Moq.) T.Cooke, Hydnora africana Thunb, Hypoxis latifolia Wight, Pelargonium sidoides DC, Psidium guajava L and
Schizocarphus nervosus (Burch.) van der Merwe were screened against Staphylococcus aureus, Escherichia coli,
Enterococcus faecalis, multi-resistant Salmonella enterica serovar Isangi, S. typhi, S. enterica serovar Typhimurium,
Shigella flexneri type 1b and Sh. sonnei phase II. A qualitative phytochemical screening of the plants extracts was
by thin layer chromatography. Plants extracts were screened for antibacterial activity using serial dilution
microplate technique and bioautography.
RESULTS : The TLC fingerprint indicated the presence of terpenoids and flavonoids in the herbs. Most of the tested
organisms were sensitive to the crude acetone extracts with minimum inhibitory concentration (MIC) values
ranging from 0.018–2.5 mg/mℓ. Extracts of A. striata, C. uncinulata, E. autumnalis and P. guajava were more active
against enteropathogens. S. aureus and Sh. flexneri were the most sensitive isolates to the crude extracts but of
significance is the antibacterial activity of A. arborescens and P. guajava against a confirmed extended spectrum
betalactamase positive S. enterica serovar Typhimurium.
CONCLUSION : The presence of bioactive compounds and the antibacterial activity of some of the selected herbs
against multidrug resistant enteric agents corroborate assertions by traditional healers on their efficacies.