Susceptibility of to Ethanolic Extract of in Vero Cells.

Background: Toxoplasmosis remains widely distributed globally and is one of the major neglected parasitic zoonotic infections. The infection is still endemic in most parts of the world due to poor control as well as challenges of the currently used medications which can be overcome by using natural products. This study evaluated the effect of ethanolic extract from the stem of (EETC) on host cell invasion and intracellular replication of .

Method: The stem powder of . was soaked in absolute ethanol for 72 hours. The resulting ethanolic extract was screened for the presence of phytochemicals. Vero cells monolayer in 96-well plate was infected with RH strain of . and treated with concentrations of the EETC, Veratrine alkaloid, and clindamycin ranging from 1.56 to 200 g/mL. MTT assay was conducted after 24 hours to evaluate the cytotoxicity and antiparasitic activities of the EETC. Four and 24 hours treatment models were adapted to assess the infection index and intracellular proliferation of .

Results: The study revealed that the EETC had no cytotoxic effects on Vero cells with IC = 179 g/mL, as compared to clindamycin (IC = 116.5 g/mL) and Veratrine alkaloid (IC = 60.4 g/mL). The EETC had good anti-toxoplasma activities with IC = 6.31 g/mL in comparison with clindamycin (IC = 8.33 g/mL) and Veratrine alkaloid (IC = 14.25 g/mL). The EETC caused more than 70% and 80% reduction in infection index and intracellular proliferation in both treatment models, respectively.

Conclusion: This study showed that the EETC contains promising phytochemicals effective against . and safe to the host cells.