Real Time Anti-<em>Toxoplasma gondii </em>Activity of an Active Fraction of <em>Eurycoma longifolia</em> Root Studied by <em>in Situ</em> Scanning and Transmission Electron Microscopy

Abstract

The inhibitory effect of active fractions of <em>Eurycoma<strong> </strong>longifolia </em>(<em>E. longifolia</em>)<em> </em>root, namely TAF355 and TAF401, were evaluated against <em>Toxoplasma gondii (T. gondii). </em>In our previous study, we demonstrated that <em>T. gondii </em>was susceptible to TAF355 and TAF401 with IC₅₀ values of 1.125 µg/mL and 1.375 µg/mL, respectively. Transmission (TEM) and scanning electron microscopy (SEM) observations were used to study the <em>in situ </em>antiparasitic activity at the IC₅₀ value. Clindamycin was used as positive control. SEM examination revealed cell wall alterations with formation of invaginations followed by completely collapsed cells compared to the normal <em>T. gondii </em>cells in response to the fractions. The main abnormality noted via TEM study was decreased cytoplasmic volume, leaving a state of structural disorganization within the cell cytoplasm and destruction of its organelles as early as 12 h of treatment, which indicated of rapid antiparasitic activity of the <em>E. longifolia</em> fractions. The significant antiparasitic activity shown by the TAF355 and TAF401 active fractions of <em>E. longifolia </em>suggests their potential as new anti-<em>T. gondii </em>agent candidates.<em> </em>

Keywords

• &lt;em&gt;Toxoplasma gondii&lt;/em&gt;
• &lt;em&gt;Eurycoma longifolia&lt;/em&gt;
• transmission electron microscope
• scanning electron microscope
• toxoplasmosis