Figure 1: Effect of different concentrations of n-frutalin and r-frutalin on HeLa cells proliferation at 24 and 48 h. Each time point is shown as mean ± SEM of at least 3 replicates ( ); * . No statistically significant differences were observed in terms of toxicity between the same concentrations of recombinant and native frutalin, regardless of concentration and time point analysed.