Fig. 3.

Neutral hibiscus tea components do not induce conformational change in HAin. (a, b) PR8 virus was mixed with an equal volume of PBS, Hib[crude], frHibis (a), or PCA (b). The pH of each aqueous solution was adjusted to acidic or approximately neutral. The pH shown was an approximate value with a range ± 0.3. The mixture was placed at 26 °C for 10 min or 48 h and mixed with an equal volume of chicken blood cells. HA titer of the mixture was evaluated after a 30-min reaction. Error bars indicate mean ± SD; n = 3 to 6 per group. Student’s t test with Bonferroni’s test (a), and Student’s t test (b) were performed to analyze statistical significance. The results represent more than two independent experiments