Backgroud: Strychnos lucida
R. Br. (Loganiaceae), a well-known indigenous medicine in Timor Leste, has been used for the treatment of ailments
such as malaria, diarrhoea, fever, hypertension, cancer, diabetes mellitus and skin infections. Its pharmacological activity has never been reported.
The aim of this study was to determine the biological activities of
S. lucida, including antimicrobial, antioxidant and anticancer activities.
Materials and methods: The stem, stem bark, twig and leaves of
S. lucida were extracted by non-polar (hexane) and polar (ethyl acetate and
methanol) solvents. Antimicrobial activity of the plant extracts against 29 microorganisms was evaluated using the agar dilution method and
antioxidant properties were determined using DPPH and SOD assays. Anticancer activity was investigated against HepG2, HuCCA-1, A549 and
MOLT-3 cell lines using the MTT and XTT assays.
Results: It was found that the hexane and ethyl acetate extracts of
S. lucida selectively inhibited the growth of Gram positive bacteria (
Bacillus subtilis
ATCC 6633,
Bacillus cereus
and
Streptococcus pyogenes
) with MICs range of 32-128 μg/mL. Antioxidant activities, radical and superoxide
scavenging properties, were observed for ethyl acetate and methanol extracts of
S. lucida. Particularly, the ethyl acetate extracts selectively showed
inhibitory activity against MOLT-3 cells. Notably, the plant extracts showed the relationship between antimicrobial, antioxidant and anticancer
activities.
Conclusion: The findings support the medicinal usage of
S. lucida.
