## 3 Results
### Pharmacological Results  
Effects on the Viability of Caco-2 Cells  
Pharmacological studies in vitro were done using MTS test and human colon cancer cell line Caco-2 (ATCC-HTB-37). Basically, studies intended the comparison of the effects on Caco-2 cell viability of control standardized extract (PlaSC) at 2 h extraction time with the effects of the three types of laser-assisted (standardized) extracts (PlaIS488, PlaSI532, and PlaSI660), also at 2 h extraction time, portraying the three types of behavior noticed in antioxidant activity assay: laser-assisted extract at 488 nm (Plal488) proved the best chemical quantitative acquisition, at the same time increased antioxidant activity in chemiluminescence study; laser-assisted extract at 532 nm (PlaSI532) proved potential pro-oxidative effects on the vegetal compounds in the extract, and laser-assisted extract at 660 nm (Plal660) proved certain pro-oxidant effects.  
The results are shown in Figure 6a,b and Table 4.  
As general comments, Figure 6a shows that, by comparison with the control extract (PlalSC), laser-assisted extract at 488 nm (PlalS488) induced an increase in the viability of Caco-2 cells, laser-assisted extract at 532 nm (PlalS532) induced a decrease in the viability of Caco-2 cells, while laser-assisted extract at 660 nm (PlalS660) had no effects on the Caco-2 cells viability. Particularity, the analysis in the area of concentrations with real practical value (more clear in Figure 6b), meaning concentration range from 5 to 10 ug GAE/mL sample, indicates a similitude with the behavior observed in antioxidant activity study: an increase of the cell viability using Plal488 extract, identical effects on the cell viability using Plal532 extract, and the decrease of the cell viability using Plal660 extract respectively; inhibitory effects of laser extract at 660 nm also was consistent, along the entire concentration range in the study, 5-100 ug GAE/mL sample.  
Another observation is that while at sample concentrations between 5 and 25 ug GAE/mL, both irradiated (Plal488, Plal532, Plal660) and control (PlalC) extracts at 2 h from _Plantaginis folium_ have proved protective effects on Caco-2 cells (Caco-2 cell viability is over 100%); the protective interval being larger in the case of extract with the highest antioxidant activity (Plal488). Starting with the sample concentration over 25 ug GAE/mL, _Plantaginis folium_ extracts have revealed cytotoxic effects, in fact the extracts  
\begin{table}
\begin{tabular}{c c} \hline \hline
**Test Sample** & **IC\({}_{50}\) (\(\mu\)g GAE/mL Sample)** \\ \hline PlalC & 132.09 \(\pm\) 1.94 \\ Plal532 & 122.59 \(\pm\) 1.76 \\ Plal660 & 134.76 \(\pm\) 1.61 \\ Plal488 & 170.94 \(\pm\) 1.97 \\ \hline \hline \end{tabular}
\end{table}
Table 4: IC\({}_{50}\) comparison.  
Figure 6: (**a**,**b**) Caco-2 cell viability at 24 h., non-irradiated control extracts (PlalSC) versus laser-assisted extracts at 488 nm (PlalS488), 532 nm (PlalS532), and 660 nm (PlalS660).  
proved an antiproliferative activity pharmacological testing being done on human colon cancer cell line (Caco-2). These effects are explained by luteolin and caffeic acid derivatives present in extracts, two effective anti-tumor natural compounds sub-classes.  
The punctual IC\({}_{50}\) values of the four tests extracts are presented in Table 4. There can be observed IC\({}_{50}\) values over 100 \(\upmu\)g GAE/mL sample, therefore a weak antitumor potency of the whole aqueous extracts from _P. lanccolata_ species; new purification stages to increase the concentration of the active compounds in the extracts are imposed, with the purpose of using _P. lanccolata_ extracts as an effective anti-tumor remedy.