## 2 Results and Discussion
### Fingerprints of Selaginella doederleinii
However, the contents of ketones, furans, phenols, terpen, and esters in SD from Guizhou Province were lower than those from Zhejiang Province, among which the difference in ketones was noticeable. The ketones in Zhejiang and Guizhou accounted for 14.93 \(\pm\) 0.68% and 11.61 \(\pm\) 0.46%, respectively, including 3-octanone, 4-oxoisophorone, 6-undecanone, 6-dodecanone, 4-(4-methoxyphenyl)-2-butanone, and phytone. Whether in SD Guizhou or SD Zhengjiang, terpen were the highest percentage compounds and accounted for nearly half of all oil samples, which represented the chemical characteristic of SD well. The most abundant terpen (Table 2) in SD, of which the concentrations were above 1%, were linalool (2.37-3.36%), aromadendrene (3.70-4.80%), zingerone (1.51-5.48%), cedrol (4.66-6.97%), anethol (0.56-12.78%), and \(\alpha\)-cadinol (1.15-2.21%). The terpen were generally considered to be active constituents in natural products [27], which exhibited antibacterial, antitumor, anti-wrinkle, antioxidative, anti-trussive, analgesia, and immune-regulatory effects [28]. For example, [PERSON] [29] and others found the treatment of linalool prevented acute ultraviolet-B-induced hyperplasia, lipid peroxidation, and anti-oxidation loss of mice skin and could further inhibited overexpression of cyclooxygenase-2 and ornithine decarboxylase in mice skin. [PERSON] [30] and others first revealed that cedrol improved the level of 5-hydroxyryptamine (5-HT), decreased the ratio of 5-hydroxyindoleacetic acid/5-HT, and had significant anxiolytic effect on female mice via the 5-HT pathways. \begin{table}
\begin{tabular}{c c c c c c c c c c c c} \hline \hline
**No** & **RP** & **Rb\({}^{b}\)** & **Rb/Min** & **Identification** & **Compounds** & **C** & **CAS** & \multicolumn{3}{c}{**Feok Areas Ratios (\%)**} & **P Value** & **Vip** \\ \hline
1 & 951 & 956 & 8.188 & STDMSKI & 2-heptginal & A & 18829-555 & 0.35 \(\pm\) 0.03 & 0.67 \(\pm\) 0.02 & 0.029 & 0.593 \\
2 & 979 & 994 & 8.874 & STDMSLLRRI & 1-octn-3-cl & B & 3931-864 & 0.21 \(\pm\) 0.02 & 0.82 \(\pm\) 0.12 & 0.006 & 1.033 \\
3 & 983 & 999 & 8.992 & MSLLRRI & 3-octnance & C & 106-68-3 & 0.33 \(\pm\) 0.16 & 0.37 \(\pm\) 0.09 & 0.679 & 0.151 \\
4 & 956 & 967 & 9.095 & MSLLRRI & 1-heptginal & B & 111-06-0 & 0.17 \(\pm\) 0.05 & 0.41 \(\pm\) 0.16 & 0.009 & 0.714 \\
5 & 999 & 988 & 9.187 & STDMSKI & 2-porphyrin & D & 377-93 & 7.50 \(\pm\) 1.25 & 5.48 \(\pm\) 0.13 & 0.003 & 1.150 \\
6 & 1099 & 1056 & 11.245 & STDMSLLRRI & 2-octnate\({}^{a}\) & A & 2548-87.0 & 1.11 \(\pm\) 0.23 & 1.92 \(\pm\) 0.38 & 0.003 & 1.226 \\
7 & 1103 & 1102 & 12.597 & STDMSLLRRI & 1-nominal & A & 124-19-6 & 0.75 \(\pm\) 0.31 & 0.59 \(\pm\) 0.25 & 0.099 & 0.470 \\
8 & 1104 & 1106 & 12.693 & STDMSLLRRI & Inalocol & H & 78-706 & 2.37 \(\pm\) 0.68 & 3.36 \(\pm\) 0.23 & 0.012 & 1.044 \\
9 & 1143 & 1142 & 13.978 & STDMSLLRRI & 4-oxyoxyborne & C & 1125-12.9 & 0.76 \(\pm\) 0.31 & 1.45 \(\pm\) 0.11 & 0.017 & 1.163 \\
10 & 1154 & 1159 & 14.475 & MSLLRRI & 2-onconcon & A & 2463-53-8 & 2.45 \(\pm\) 0.16 & 1.46 \(\pm\) 0.06 & 0.009 & 0.927 \\
11 & 1183 & 1181 & 14.767 & MSLLRRI & trypsin-cl+1 & H & 567-34.7 & 0.85 \(\pm\) 0.26 & 0.83 \(\pm\) 0.05 & 0.475 & 0.237 \\
12 & 1204 & 1201 & 15.45 & STDMSLLRRI & 4-alkylinhalence\({}^{c}\) & F & 146-07.0 & 0.31 \(\pm\) 0.18 & 0.73 \(\pm\) 0.12 & 0.001 & 0.836 \\
13 & 1207 & 1203 & 15.9  
\begin{tabular}{c c c c c c c c c c c c} \hline \hline \multicolumn{1}{c}{**No**} & \multicolumn{1}{c}{**R\({}^{\rm I\!P}\)**} & \multicolumn{1}{c}{**R\({}^{\rm I\!P}\)**} & \multicolumn{1}{c}{**R/Min**} & \multicolumn{1}{c}{**Identification**} & \multicolumn{1}{c}{**Compounds**} & \multicolumn{1}{c}{**C**} & \multicolumn{1}{c}{**CAS**} & \multicolumn{1}{c}{**Peak Areas Ratios (\%)**} & \multicolumn{1}{c}{**P Value**} & \multicolumn{1}{c}{**Vip**} \\ \hline
39 & 1502 & Nr & 24.102 & STDAS,LR,RI & tetrahedral\({}^{\rm I\!P}\) & A & 124-25-4 & 0.26 \(\pm\) 0.06 & 0.33 \(\pm\)  
However, the pharmacological activity of terpene from SD has not been reported.