Figure 4.

Cell viability recovery of old (a) and young (b) leaf extract of Halophila stipulacea on the WI38 cell line. The WI-38 cells were injured with 10 mM of H₂O₂ for 2 h and then recovered with three concentrations of the extracts (1, 10, and 100 μg·mL⁻¹) for 48 h. Data are shown as mean ± S.D. The means for the two greatest leaf extract concentrations (10 and 100 μg·mL⁻¹) were significantly different between old and young leaves (p < 0.001). No significant difference (p > 0.05) between old and young leaf extracts at the lowest concentration (1 μg·mL⁻¹).