2.13. Statistical analysis
Data were presented as mean ± SD. Statistical significance of difference
among treatments was calculated using one-way analysis of variance
and covariance (ANOVA) according to the Tukey–Kramer all-pair comparisons
at significance level of 0.05 (⁎p b 0.05), 0.01 (⁎⁎p b 0.01), or 0.001
(⁎⁎⁎p b 0.001) with respect to the control