Abstract:
OBJECTIVE : To evaluate the biological activities of Combretum erythrophyllum
(C. erythrophyllum) leaf extracts against infectious diseases' pathogenesis and their
cytotoxicity potentials.
METHODS : Powdered leaf material (300 g) of C. erythrophyllum was extracted (1:10 w/v)
using acetone to obtain the crude extract. Liquid–liquid fractionation was performed on
the crude acetone extract (30 g) using solvents of different polarity. The bioautographic
method was used to detect the inhibition of bacterial and fungal growth by active compounds
present in the crude and fractions. The extracts were then tested on bacterial
strains: Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Pseudomonas
aeruginosa; fungal strains: Candida albicans (C. albicans), Cryptococcus neoformans,
and Aspergillus fumigatus, by microtitre dilution method for MIC determination.
RESULTS : The extracts MIC values ranged between 0.08 and 2.50 mg/mL against the
tested pathogens. Water fraction had the highest activity against bacteria strains, while the
fungal assay revealed crude acetone extract and ethyl acetate fraction to be active against
C. albicans (1.25 mg/mL), dichloromethane extract against C. albicans and A. fumigatus
(0.16 mg/mL). Extract fractions showed a good antioxidant activity via DPPH,
ABTS and hydroxyl radical scavenging assays, in the order: ethyl
acetate > water > acetone > dichloromethane > hexane. The toxicity level of crude
extract and fractions evaluated in Vero monkey kidney cells ranged from 34 to 223 mg/
mL, while doxorubicin (IC50 = 7.19 mg/mL) served as the positive control.
CONCLUSIONS : It can be concluded that the extracts of C. erythrophyllum are safe for
medicinal use in folk medicine for treating infectious and stress related diseases.
