## 3 Results
### Dpph  
The antioxidant activity of the obtained extracts varied from 29.41 to 70.14 \(\mu\)M TE: g\({}^{-1}\). Similar results were obtained by [PERSON], who determined the antioxidant activity of different varieties of _C. sativa_ cannabis infloresesences in the range from 27.532 to 77.578 \(\mu\)M TE g\({}^{-1}\)[44]. The result of ANOVA analysis showed that the linear and quadratic effects of particle size, time and intensity and the two-level interaction of time and intensity were significant terms. The variable particle size was the most significant factor associated with the response DPPH test. However, the quadratic term of this variable demonstrated a negative correlation resulting in decreasing in the antioxidant activity of the extract when the particle size overcome a certain value (Figure 3). \begin{table}
\begin{tabular}{c c c c c c c} \hline
**Source** & **Sum of Squares** & **df** &
\begin{tabular}{c} **Mean** \\ **SQUARE** \\ \end{tabular} & \(F\) **Value** & \(p\)**-Value** & **Coefficient** \\ \hline Model & 149.95 & 7 & 21.42 & 55.06 & \(<\)0.0001 & significant \\ \(X_{1}\) & 23.57 & 1 & 23.57 & 60.57 & 0.0001 & +20.94388 \\ \(X_{2}\) & 12.18 & 1 & 12.18 & 31.29 & 0.0008 & +1.77384 \\ \(X_{3}\) & 36.31 & 1 & 36.31 & 93.32 & \(<\)0.0001 & +2.66394 \\ \(X_{2}X_{3}\) & 8.10 & 1 & 8.10 & 20.82 & 0.0026 & \(-0.081327\) \\ \(X_{1}^{2}\) & 60.95 & 1 & 60.95 & 156.64 & \(<\)0.0001 & \(-16.25101\) \\ \(X_{2}^{2}\) & 7.14 & 1 & 7.14 & 18.35 & 0.0036 & \(-0.055617\) \\ \(X_{3}^{2}\) & 8.21 & 1 & 8.21 & 21.11 & 0.0025 & \(-0.121763\) \\ \hline Residual & 2.72 & 7 & 0.3891 & & & \\ \hline Lack of Fit & 2.39 & 5 & 0.4788 & 2.90 & 0.2757 & not significant \\ \hline Pure Error & 0.3297 & 2 & 0.1648 & & & \\ \hline Total & 152.67 & 14 & & & & \\ \hline \end{tabular} R\({}^{2}\) = 0.9822. adj-R\({}^{2}\) = 0.9643. CV = 5.32. Adeq Precision 20.6375.  
\end{table} 
Table 1: ANOVA results for response: the total phenolic content. Figure 3: Response surfaces for the DPPH test (μMTE\(\cdot\)g\({}^{-1}\)) showing the effect of (**a**) time and particle size, (**b**) size particle and intensity, (**c**) intensity and time. The antioxidant activity increased as the particle size increased from 0.25 mm to 0.75 mm, and decreased as the particle size went up from 0.75 mm to 1.25 mm. The antioxidant activity measured by the DPPH test increased with the increase in the extraction time. A similar tendency was observed as regards the intensity of the applied ultrasounds, the antioxidant activity measured by the DPPH test increased with the increase of the ultrasound intensity during the extraction process. The effect of particle size on the antioxidant properties of extracts was also observed by other authors [47; 48; 49; 50]. [PERSON] [47] showed that the free radical scavenging activity of water extracts of tea and ginger increased as the particle size was reduced from 1.180 mm to 0.425 mm. The observations carried out by the same author also showed that the optimal particle size that maximizes the antioxidant activity of the extracts depends on the solvent used, as well as the type of test applied to assess the antioxidant properties (DPPH, ABTS, peroxide, iron) [47]. Particle size is one of the most significant factors influencing the efficiency and antioxidant properties during conventional extraction methods, including maceration, and percolation, as it affects the access of the solvent to the solutes, and, thus, the mass transfer kinetics. The rise in the degree of fragmentation leads to the expansion of the contact area of the solvent with the surface of the particle and increases the diffusivity of the solvent. On the other hand, excessive fragmentation causes small particles may remain on the surface of the solvent, which significantly reduces the number of active substances passing into the solvent, and, thus, the antioxidant capacity of the extracts too.