## 3 Results and Discussion
### Chemical Composition of EOs
#### 3.2.3 Comparison to Previous Studies on \(C\). japonica  
Leaf EO Isolated by HD  
Table 4 shows data from the literature on the main components of EO-HD samples from leaves of red heartwood-type \(C\). _japonica_ according to geographic region, for comparative purpose. As can be observed, deep differences were found, not only in the identity of the EO components but also in their percentage. Nonetheless, on a basis of the component groups (MH, OCM, SH, OCS, and DH), a similar pattern was found in all \(C\). _japonica_ OE samples (Table 4), as summarized below. \begin{table}
\begin{tabular}{c c c c c c c c c c c c c} \hline \hline \multirow{2}{*}{**Main Components**} & \multicolumn{3}{c}{**São**} & \multicolumn{3}{c}{**Cryptomeria japonica** Origin} & \multicolumn{3}{c}{**Cryptomeria japonica** Origin} & \multicolumn{3}{c}{**Caíwan**} \\ \cline{2-13}  & **São** & **Kerala Island** & **Kerala Island** & **Kerala Island** & **Japan** [28] & **China [1]\({}^{\text{3}}\)** & **Nepal [17]** & **Korea** & & & **Taiwan** \\ \cline{2-13}  & **Island,** & **Azores 2** & **Island [48]** & **Island [51]** & & & & **[15]** & **[25]** & **[27]** & **[36]** & **[33]** & **[34]** \\ \hline MH group & & & & & & & & & & & & & \\ \(\alpha\)-Thujene & 2.1 & 1.4 & - & 0.9 & 0.5 & 0.3 & 1.2 & - & 0.6 & 0.9–1.3 & 0.5 & 0.8 \\ \(\alpha\)-Pinene & **34.5** & 19.1 & **16.7** & **13.1** & 8.0 & 4.2 & 9.8 & 3.5 & 3.0 & 4.4–  
Concerning the MH group, the OE samples were characterized by the association of \(\alpha\)-pinene and sabinene as major MH or by the dominance of \(\alpha\)-pinene, except for one Taiwan EO sample [34] that presented the following decreasing order of abundance in their major MH: \(\delta\)-3-carene \(\approx\) sabinene \(>\alpha\)-pinene. In the OCM group, terpinen-4-ol was the main component, except (i) for one Korean EO sample [15], in which \(\alpha\)-terpineol presented the highest content followed by terpinen-4-ol, and (ii) for the Japanese [28] and one Taiwan [33] EO samples, in which the main OCM was bornyl acetate followed by terpinen-4-ol. Relative to the SH group, \(\delta\)-cadinene was the only SH that was found in all samples, presenting the highest or similar content compared with the other SH, except for Japanese [28] and Chinese [1] EO samples, which were dominated by thujopense and \(\beta\)-elemene, respectively. In the OCS group, elemol presented the highest content, except (i) for two Korean EO samples, in which \(\alpha\)-eudesmol [15] and \(\gamma\)-eudesmol [27] presented the highest content, and (ii) for the Chinese EO sample [28], which was dominated by \(\alpha\)-elemol, which was reported for the first time in \(C\). _japonica_ EO composition [28]. In relation to the DH group, kaurene was dominant in the Corsica Island, Reunion Island, Japan, and Korea EO samples, while kaur-16-ene (ent-kaurene) was dominant in the China, Nepal, and Taiwan EO samples. The two DHs mentioned above are absent in our EO sample that, in contrast, was the only one that presented the DH phyllocladene. In fact, the alternative occurrence of (\(-\)) kaurenene or (\(+\)) phyllocladene in the leaves of \(C\). _japonica_ was discussed in previous studies [51]. Similar to Sao Miguel Island (Azores, Portugal), \(C\). _japonica_ from Japan was introduced during the last century in other European countries, such as in Corsica [48] and Reunion [51] Islands (France). As can be observed in Table 4, the EOs from Corsica [48] and the Sao Miguel Islands were characterized by the association of \(\alpha\)-pinene, sabinene, and elemol as major components, decreasing in the following order of abundance: \(\alpha\)-pinene \(>>\) sabinene \(>>\) elemol in Sao Miguel, and sabinene \(\approx\alpha\)-pinene \(>>\) elemol in Corsica. On the other hand, the Corsica EO sample was richer in limonene and a good source of the DH kaurene, which was absent in our EO sample (Table 4), as mentioned above.