# Anthocyanins, Phenolic Compounds, and Antioxidants from Extractions of Six _Eucalyptus_ Species
## 4 Discussion  
### Total Extraction Yield Analysis  
[PERSON] et al. (2019) studied the effects of solvent type on palm seed oil and found that polar solvents such as methanol and ethanol gave better total yields than those with lower polarity such as acetone. However, they also suggested particle size could influence percentage of extraction yield. Thus, they determined the diminution in particle size caused an increase of yields. [PERSON] et al. (2019) discovered that polar solvents, for instance water \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline  & \multicolumn{6}{c}{**Antioxidant Activity (mmol g\({}^{-1}\) DW)**} \\ \hline \hline
**Solvent** & \multicolumn{2}{c}{_E. globulus_} & \multicolumn{2}{c}{_E. oblicua_} & \multicolumn{2}{c}{_E. parawiflora_} & \multicolumn{2}{c}{_E. canalalucensis_} & \multicolumn{2}{c}{_E. viiminalis_} & \multicolumn{2}{c}{_E. nitens_} \\ \hline \multirow{3}{*}{AC} & ABTS & 10.72 \(\pm\) 0.32 b  & 6.21 \(\pm\) 0.27 b  & 7.54 \(\pm\) 0.07 b  & 3.45 \(\pm\) 0.14 b  & 9.43 \(\pm\) 0.14 b  \\ \cline{2-7}  & CUPRAC & 3.44 \(\pm\) 0.21 b  & 1.25 \(\pm\) 0.46 b  & 1.47 \(\pm\) 0.21 b  & 1.21 \(\pm\) 0.15 b  & 1.39 \(\pm\) 0.24 b  & 3.14 \(\pm\) 0.06 b  \\ \hline \multirow{3}{*}{ETH} & ABTS & 1.68 \(\pm\) 0.07 b  & 0.85 \(\pm\) 0.08 a  & 1.71 \(\pm\) 0.08 a  & 0.65 \(\pm\) 0.13 a  & 1.01 \(\pm\) 0.14 a  & 1.23 \(\pm\) 0.12 a  \\ \cline{2-7}  & CUPRAC & 0.49 \(\pm\) 0.08 a  & 0.43 \(\pm\) 0.04 a  & 0.99 \(\pm\) 0.11 a  & 0.33 \(\pm\) 0.02 b  & 0.45 \(\pm\) 0.16 a  & 0.75 \(\pm\) 0.04 a  \\ \hline \multirow{3}{*}{MTH} & ABTS & 9.27 \(\pm\) 0.07 b  & 5.34 \(\pm\) 0.16 b  & 4.23 \(\pm\) 0.08 a  & 2.42 \(\pm\) 0.10 b  & 1.55 \(\pm\) 0.06 b  & 8.08 \(\pm\) 0.18 b  \\ \cline{1-1} \cline{2-7}  & CUPRAC & 2.50 \(\pm\) 0.10 a  & 2.31 \(\pm\) 0.05 a  & 1.00 \(\pm\) 0.01 a  & 0.85 \(\pm\) 0.06 b  & 1.47 \(\pm\) 0.14 b  & 0.45 \(\pm\) 0.09 a  \\ \hline \hline \end{tabular} Statistical significances of antioxidant capacities values are shown in superscripts letters: a statistically significant differences versus values of DCH extract; b versus values of MTH extract, c versus values of ETH extract, d versus values of W, e versus values of HEX, and f versus values of AC (\(p<0.05\)).  
\end{table} 
Table 6: Antioxidant capacity of extracts of _Eucalyptus_ leaves assessed by ABTS, CUPRAC. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline  & \multicolumn{6}{c}{**Antihocyanis (mg CAE/g of Extract)**} \\ \hline \hline
**Solvent** & \multicolumn{2}{c}{_E. globulus_} & \multicolumn{2}{c}{_E. oblicua_} & \multicolumn{2}{c}{_E. parawiflora_} & \multicolumn{2}{c}{_E. canalalucensis_} & \multicolumn{2}{c}{_E. viiminalis_} & \multicolumn{2}{c}{_E. nitens_} \\ \hline DCH & 2.32 \(\pm\) 0.16 d,e [FOOTand ethanol, gave better yields than non-polar solvents in a study in which they analysed the effects of solvent type on the extraction yield of bioactive compounds in _Pinus nitriri_. In addition, incorporating water to acetone and ethanol did increase the extract yield [35]. On the same line, [PERSON] et al. [36] determined that the polar solvents methanol and water increased percentage yields compared to other non-polar solvents. As in other studies, they also suggested that particle size influenced the effectiveness of the extraction, and the larger the particle, the lower the yields obtained. Extraction yields are different between species: _E. viimialis_ gives the highest yields, ranging from 19.5 to 42.5 wt.%, while _E. paauflora_ gives the lowest yields ranging from 9.4 to 32.3 wt.%. Available literature also indicates variation in extraction yields between different species of _Eucalyptusptus_. [PERSON] et al. [5] reported Soxhet extraction yields of 11.3% for _E. viimialis_, 8.6% for _E. globulus_, and 14.8% for _E. camaludensis_. These extractions were done with a 50% aqueous ethanol solution of the barks, which could confirm the influence of solvents and the parts of the plant used on the percentage of extraction. [PERSON] et al. [6] reported for _E.