Fig. 5. Transmission electron microscopy (TEM) image analysis confirms that a 60% ethanol extract of Echinacea purpurea (EPE) and chicoric acid (CA) can inhibit virus infection in host cells. Madin-Darby canine kidney (MDCK) cells are infected with H3N2, H1N1, or influenza B virus (IVB), whereas HEp-2 cells are infected with respiratory syncytial virus subtype A (RSV-A). Following infection, they are treated with 1,000 µg/mL EPE or 189.75 µg/mL CA. Subsequently, TEM is then employed to assess the extent of viral infection. (A) Uninfected MDCK cell (×10 k magnification), (B) Solvent control of H1N1-infected MDCK (×10 k magnification), (C) H1N1-infected MDCK with EPE (×10 k magnification), (D) H1N1-infected MDCK with CA (×10 k magnification), (E) Solvent control of IVB-infected MDCK (×10 k magnification), (F) IVB-infected MDCK with EPE (×10 k magnification), (G) IVB-infected MDCK with CA (×10 k magnification), (H) Uninfected HEp-2 cell (×30 k magnification), (I) Solvent control of RSV-A-infected HEp-2 (×30 k magnification), (J) RSV-A-infected HEp-2 with EPE (×30 k magnification), (K) RSV-A-infected HEp-2 with CA (×30 k magnification). Virus particles are indicted by arrowhead. Scale bar: 1 mm (A, B, C, D, E, F, and G) or 500 nm (H, I, J, and K).

Prev Nutr Food Sci 2024;29:332~344 https://doi.org/10.3746/pnf.2024.29.3.332