Figure 1.
Antiviral activity of Plantago asiatica extract (PAE) and Clerodendrum trichotomum extract (CTE) in HEp2 cells and A549 cells. HEp2 cells and A549 cells were seeded into 12 well cell culture plates with the cell number of 2.5 × 105 cells/well. Twelve hours later, the medium was changed to 1% fetal bovine serum (FBS) containing Dulbecco’s Modified Eagle’s Medium (DMEM) and cells were infected with Green Fluorescent Protein fused Respiratory syncytial virus (RSV-GFP) 0.1multiplicity of infection (MOI) or kept uninfected. Two hours later, the medium was replaced with 10% FBS containing DMEM and cells were treated with 10, 30, 50 (μg/mL) PAE or CTE. Cells without any treatment regard as virus only. (A) After 48 h, images were obtained (200× magnification). (B) GFP absorbance levels were measured by Gloma multi-detection luminometer (Promega). (C) Virus titration was done from the cell supernatant and cells by standard plaque assay and expressed as plaque forming unit (PFU). (D) Cell viability was determined by trypan blue exclusion assay at 48hour post infection (hpi). GFP absorbance, cell viability and virus titer expressed as mean ± standard deviations (SD). Error bars indicate the range of values obtained from counting duplicate in three independent experiments (** p < 0.01 and *** p < 0.001 regarded as significant difference).