# Evaluation of Different Drying Methods on the Quality Parameters of _Acanthopanax semicosus_ Fruits
## 3 Results
### Quantitative Analysis of Main Active Ingredients
\begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Sample Code** & **HD** & **VD** & **ND** & **MD** & **VFD** \\ \hline Protocatechic acid (mg/100 g) & 5.4 \(\pm\) 0.3 \({}^{\text{a}}\) & 1.8 \(\pm\) 0.2 \({}^{\text{d}}\) & 3.5 \(\pm\) 0.1 \({}^{\text{b}}\) & 3.6 \(\pm\) 0.1 \({}^{\text{b}}\) & 2.5 \(\pm\) 0.2 \({}^{\text{c}}\) \\ Chlorogenic acid (mg/100 g) & 294 \(\pm\) 2 \({}^{\text{d}}\) & 71.6 \(\pm\) 0.2 \({}^{\text{e}}\) & 499 \(\pm\) 1 \({}^{\text{b}}\) & 486 \(\pm\) 8 \({}^{\text{c}}\) & 601 \(\pm\) 6 \({}^{\text{a}}\) \\ Rutin (mg/100 g) & 15.5 \(\pm\) 0.3 \({}^{\text{b}}\) & 6.7 \(\pm\) 0.6 \({}^{\text{d}}\) & 6.9 \(\pm\) 0.3 \({}^{\text{d}}\) & 13.9 \(\pm\) 0.4 \({}^{\text{c}}\) & 23.3 \(\pm\) 0.6 \({}^{\text{a}}\) \\ Hyperoside (mg/100 g) & 72.0 \(\pm\) 1.5 \({}^{\text{b}}\) & 40.0 \(\pm\) 0.4 \({}^{\text{e}}\) & 42.3 \(\pm\) 1.6 \({}^{\text{d}}\) & 68.1 \(\pm\) 3.7 \({}^{\text{c}}\) & 96.6 \(\pm\) 1.2 \({}^{\text{a}}\) \\ Isofrakidin (mg/100 g) & 2.32 \(\pm\) 0.03 \({}^{\text{a}}\) & 0.52 \(\pm\) 0.03 \({}^{\text{d}}\) & 1.28 \(\pm\) 0.03 \({}^{\text{c}}\) & 0.49 \(\pm\) 0.02 \({}^{\text{d}}\) & 1.67 \(\pm\) 0.05 \({}^{\text{b}}\) \\ Quercitrin (mg/100 g) & 238 \(\pm\) 5 \({}^{\text{d}}\) & 66.9 \(\pm\) 1.3 \({}^{\text{e}}\) & 434 \(\pm\) 4 \({}^{\text{b}}\) & 351 \(\pm\) 5 \({}^{\text{c}}\) & 535 \(\pm\) 6 \({}^{\text{a}}\) \\ Eleutheroside B (mg/100 g) & 65.9 \(\pm\) 1.1 \({}^{\text{c}}\) & 21.0 \(\pm\) 0.3 \({}^{\text{d}}\) & 124 \(\pm\) 1 \({}^{\text{b}}\) & 69.2 \(\pm\) 3.8 \({}^{\text{c}}\) & 162 \(\pm\) 2 \({}^{\text{a}}\) \\ Eleutheroside E (mg/100 g) & 20.5 \(\pm\) 0.5 \({}^{\text{a}}\) & 11.8 \(\pm\) 0.2 \({}^{\text{d}}\) & 16.4 \(\pm\) 0.4 \({}^{\text{c}}\) & 17.3 \(\pm\) 0.7 \({}^{\text{b}}\) & 16.4 \(\pm\) 0.2 \({}^{\text{c}}\) \\ \hline \hline \end{tabular} Different letters (a–e) indicate significant differences (\(p\leq\) 0.05) among drying methods within the same row (same chemical compound).  
\end{table} 
Table 2: Analysis of variance in active ingredients of AS fruits subjected to different drying methods by UHPLC-UV. a coumarin compound, exhibits thermal stability due to its conjugated system, which mitigates oxidative stress and resists enzymatic degradation. Under HD conditions, it remains relatively stable, as it is not a primary substrate for enzymatic reactions in fruits. Although VFD retained lower levels of eleutheroside E and isofrazvidin than HD, it outperformed other drying methods. VD, conducted under low pressure, resulted in poor bioactive compound retention, likely due to prolonged drying times. ND, a slow process with extended light and humidity exposure, led to significant losses of key compounds such as rutin and hyperoside. Previous research indicated that hot-air flow rolling dry-blanching pretreatment significantly improved drying efficiency and enhanced phenolic and flavonoid retention by inhibiting oxidative enzymes in AS fruits [36]. Similarly, freeze-drying demonstrated superior retention of total phenolics and beta-carotene in African eggplant, confirming the advantage of low-temperature drying for preserving bioactive components [37].