Fig. 4

Effects of SBT twig and leaf extracts (0.5–50 μg/mL; 15 min (a) and 60 min (b)) on plasma protein carbonylation induced by H₂O₂/Fe. In these experiments the carbonyl group level (marker of protein oxidation) in control samples (plasma treated only with H₂O₂/Fe) was 30.4 ± 5.1 nmol/mg of plasma protein. Data represent means ± SD of 6–12. The effect of five different concentrations of two tested extracts (0.5, 1, 5, 10 and 50 μg/mL; for 15 min) was not statistically significant (p > 0.05 (n.s.)) in comparison to control. The effect of five different concentrations of SBT twig extract (0.5, 1, 5, 10 and 50 μg/mL; for 60 min) was statistically significant (*p < 0.05) in comparison to control. The effect of three different concentrations of SBT leaf extract (5, 10 and 50 μg/mL; for 60 min) was statistically significant (*p < 0.05) in comparison to control. The effect of two different concentrations (0.5 and 1 μg/mL; for 60 min) was not statistically significant (p > 0.05 (n.s.)), in comparison to control. The effects were not statistically significant: SBT twig extract-treated plasma vs. SBT leaf extract-treated plasma (for 15 min, p > 0.05 (n.s.); for all tested concentrations- 0.5 - 10 μg/mL). The effects were not statistically significant: SBT twig extract-treated plasma vs. SBT leaf extract-treated plasma (for 60 min, p > 0.05 (n.s.); for three tested concentrations- 0.5 - 5 μg/mL). The effects were statistically significant: SBT twig extract-treated plasma vs. SBT leaf extract-treated plasma (for 60 min, p < 0.05; for two tested concentrations- 10 and 50 μg/mL). black diagram – control, white diagram – twig, grey diagram - leaf