title: Real time anti-Toxoplasma gondii activity of an active fraction of Eurycoma longifolia root studied by in situ scanning and transmission electron microscopy.
abstract: The inhibitory effect of active fractions of Eurycoma longifolia (E. longifolia) root, namely TAF355 and TAF401, were evaluated against Toxoplasma gondii (T. gondii). In our previous study, we demonstrated that T. gondii 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 in situ 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 T. gondii 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 E. longifolia fractions. The significant antiparasitic activity shown by the TAF355 and TAF401 active fractions of E. longifolia suggests their potential as new anti-T. gondii agent candidates.
authors.affiliation: Institute for Research in Molecular Medicine-INFORMM, Universiti Sains Malaysia, Pulau Pinang 11800, Malaysia.
authors.forename: Nowroji
authors.initials: N
authors.lastname: Kavitha
authors.forename: Rahmah
authors.initials: R
authors.lastname: Noordin
authors.forename: Chan
authors.initials: C
authors.lastname: Kit-Lam
authors.forename: Sreenivasan
authors.initials: S
authors.lastname: Sasidharan
mesh_terms: D000818:Animals; D000981:Antiprotozoal Agents / Q000494:pharmacology*; D002522:Chlorocebus aethiops; D035701:Eurycoma / Q000737:chemistry*; D006790:Host-Parasite Interactions / Q000187:drug effects; D020128:Inhibitory Concentration 50; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D010936:Plant Extracts / Q000494:pharmacology*; D018517:Plant Roots / Q000737:chemistry*; D014122:Toxoplasma / Q000187:drug effects* / Q000648:ultrastructure; D014709:Vero Cells
chemical_list: D000981:Antiprotozoal Agents; D010936:Plant Extracts