## 2 Results
### Antiproliferative and Cytotoxic Activities  
To evaluate the antiproliferative activity and cytotoxic effect of leaf extract of Orte 1, Orte 2 and Grato 1 genotypes, MTT assays were performed in a dose- and time-dependent manner on human cancer cell lines (SH-SY5Y, MCF7 and MDA cell lines) and the human normal cell line (MCF10A cell line). The antiproliferative activity of the extracts was studied by measuring the cell viability of cancer and normal cells after exposure for 24 h, 48 h, and 72 h. As shown in Table 3, the leaf extracts demonstrated dose- and time-dependent anti-proliferative activity on MCF7 and MDA cells. The EC5\({}_{0}\) values of Orte 1 leaf extract against MCF7 and MDA cells decreased significantly by 50% with an increasing treatment time from 24 h to 48 h (85.2 \(\pm\) 2.3 ug/mL to 44.7 \(\pm\) 4.2 ug/mL for MCF-7 and 69.0 \(\pm\) 2.3 ug/mL to 33.4 \(\pm\) 0.9 ug/mL for MDA), and, particularly, a more significant inhibition of growth was observed at \begin{table}
\begin{tabular}{l c c c} \hline \hline
**Components 1** & **LRI 2** & **LRI 3** & **Ote 1** & **Ote 2** & **Gato 1** \\ \hline
3-methyl-1-butanol & 699 & 700 & 39.9 \(\pm\) 3.6 & 71.4 \(\pm\) 9.5 & 73.4 \(\pm\) 10.1 \\
2-methyl-1-butanol & 748 & 744 & 21.0 \(\pm\) 2.1 & 28.4 \(\pm\) 0.1 & 26.6 \(\pm\) 5.1 \\
3-hexen-1-ol & 868 & 875 & 39.1 \(\pm\) 4.1 & n.d. & n.d. \\ \(\beta\)-caryophyllene & 1414 & 1418 & n.d. & 0.1 \(\pm\) 0.0 & n.d. \\ \(\beta\)-eudesmene & 1488 & 1481 & n.d. & 0.1 \(\pm\) 0.0 & n.d. \\ \hline \hline \end{tabular}  
* The components are reported according to their elution order on apolar column; 2 linear retention indices measured on apolar column; 3 linear retention indices from literature; n.d. not detected.  
\end{table} 
Table 2: Chemical volatile composition (percentage mean value \(\pm\) SD) of Orte 1, Orte 2, and Grato 1 fresh leaves. 72 h, with a decrease in EC\({}_{50}\) values to 23.3 \(\pm\) 1.2 \(\mu\)g/mL and 26.5 \(\pm\) 1.2 \(\mu\)g/mL for MCF7 and MDA, respectively. No time-dependent effect was obtained for Orte 1 leaf extract on SH-SY5Y cells, as evidenced by the EC\({}_{50}\) values of 18.3 \(\pm\) 0.2 \(\mu\)g/mL, 12.6 \(\pm\) 0.5 \(\mu\)g/mL and 35.4 \(\pm\) 1.2 \(\mu\)g/mL at 24 h, 48 h and 72 h respectively. As regards the Orte 2 leaf extract, a progressive reduction in EC\({}_{50}\) values in MCF7 cells was observed from \(>\)250 \(\mu\)g/mL at 24 h to 33.6 \(\pm\) 1.6 to \(\upmu\)g/mL at 72 h. A slighter trend was also observed for MDA cells with EC\({}_{50}\) of 75.6 \(\pm\) 1.8 \(\upmu\)g/mL to 40.1 \(\pm\) 2.9 \(\upmu\)g/mL at 24 h and 72 h, respectively. Like Orte 1, the antiproliferative activity of Orte 2 leaf extract on SH-SY5Y cells was not correlated with the treatment exposure time (51.8 \(\pm\) 5.3 \(\upmu\)g/mL, 47.1 \(\pm\) 9.1 \(\upmu\)g/mL and 59.8 \(\pm\) 3.6 \(\upmu\)g/mL at 24 h, 48 h and 72 h, respectively). The antiproliferative activity was observed on MDA cell lines with EC\({}_{50}\) values ranging from 49.2 \(\pm\) 0.5 \(\upmu\)g/mL to 17.7 \(\pm\) 0.4 \(\upmu\)g/mL at 24 h and 72 h for Grato 1 leaf extract. The cytotoxicity effect of the extracts was assessed by examining the cell viability at 72 h. The results showed that leaf extracts of all three genotypes induced a potent dose-dependent cytotoxic effect on the considered cancer cell lines (Figure 1). Orte 1 and Orte 2 leaf extracts showed good cytotoxicity with low EC\({}_{50}\) values ranging from 23.3 \(\pm\) 1.2 \(\upmu\)g/mL on MCF7 cells for Orte 1 to 59.8 \(\pm\) 3.6 \(\upmu\)g/mL on SH-SY5Y cells for Orte 2. With a lower EC\({}_{50}\) value, the leaf extract of the Grato 1 plants was more cytotoxic against MDA cells (17.7 \(\pm\) 0.4 \(\upmu\)g/mL). Furthermore, all the extracts studied showed no antiproliferative activity or cytotoxic effect on normal cell line (MCF10A), indicating that these extracts are selective toward human cancer cells with minimal toxicity on normal human cells (Table 3).