## 3 Results
### Fourier Transform Infrared Spectroscopy
Effect of AGB and AGP Fractions on the Accumulation of Phenolic Compounds in the Roots and the Leave Tissues of Tomato Seedlings  
The accumulation of polyphenols in the leaves and the roots of tomato plants was significantly (\(p<0.05\)) triggered after treatment by AGB and AGP compared to the control. These responses depended on the incubation period. Compared to the control, the injection of AGB strongly increased the levels of polyphenols, reaching peak values 5 and 2 times higher in the leaves and the roots, respectively, after 48 h (Figure 6). In response to AGP infiltration, the total phenolic compounds rose sharply after 12 h and 48 h in the leaves, and after 12 and 24 h of treatment in the roots (Figure 6). Figure 4: Stimulation of PAL activity in the leaves (**a**) and the roots (**b**) of tomato seedlings after injection (10 \(\mu\)L) of AGB and AGP fractions (1 g/L). Each value is the mean of four repetitions \(\pm\) SE. The letters (a, b, o) indicate significant differences between treatments (Control, AGB, and AGP) in each point time using Tukey-HSD test, at (\(p<0.05\)). Treatments presented with the same letter are not significantly different. Figure 5: Stimulation of PAL activity in the leaves (**a**) and the roots (**b**) of tomato seedlings after foliar spray (20 mL) of AGB and AGP fractions (1 g/L). Each value is the mean of four repetitions \(\pm\) SE. The letters (a, b) indicate significant differences between treatments (Control, AGB, and AGP) in each point time using a Tukey-HSD test at (\(p<0.05\)). Treatments presented with the same letter are not significantly different. After foliar treatments, both sulfated polysaccharides showed a substantial accumulation of total polyphenols in the leaves after 12 h of incubation, to achieve a significant drop in the following days. For plants treated by AGB fractions, levels hit the lowest point after 24 h and 48 h of treatment compared to the control (Figure 7a). Nevertheless, the synthesis of these metabolites was mobilized to the root tissue, reaching higher values after 24 h and 48 h in response to AGP application and after 48 h in the plants treated by AGB extracts (Figure 7b). Compared to the AGB, the elicitor capacity of AGP was more efficient in the roots (Figure 7b). Globally, the AGB fractions showed a considerable increase of polyphenols in the leaves, whereas the AGP showed an important accumulation of these metabolites in the roots (Figures 7 and 8). Figure 6: Accumulation of phenolic compounds in the leaves (**a**) and the roots (**b**) of tomato seedlings after injection (10 \(\mu\)L) of AGB and AGP fractions (1 g/L). Each value is the mean of four repetitions \(\pm\) SE. The letters (a, b, o) indicate significant differences between treatments (Control, AGB, and AGP) in each point time using the Tukey-HSD test, at (\(p\) < 0.05). Treatments presented with the same letter are not significantly different. Figure 7: Accumulation of phenolic compounds in the leaves (**a**) and the roots (**b**) of tomato seedlings after foliar spray (20 mL) of AGB and AGP fractions (1 g/L). Each value is the mean of four repetitions \(\pm\) SE. The letters (a, b, o) indicate significant differences between treatments (Control, AGB, and AGP) in each point time using the Tukey-HSD test, at (\(p\) < 0.05). Treatments presented with the same letter are not significantly different. Effect of AGB and AGP Fractions on the Lignin Content in the Root and the Leaf Tissues of Tomato Seedlings  
The AGB and AGP fractions showed significant elicitor activity by stimulating the lignin synthesis in the leaves and the roots of the 45-day-old tomato seedlings. The responses were related to the incubation period (\(p<0.05\)). The lignin contents were initially increased in the leaves at 24 h and 72 h after the injection of purified polysaccharides (AGP) (Figure 8a). These metabolites were promoted in the roots after 24 h and 72 h in response to AGP and AGB, respectively (Figure 8b). The AGB did not show a significant response in the leaves.