## 3 Results  
### Phytochemical Profiling of Syzygium formosum Leaves Using LC-MS/MS  
The phytochemicals in _S. formosum_ leaves were tentatively identified based on the retention time and mass to charge (_m_/_z_) ratio using both positive and negative ionization full scan modes. In the scan mode, we can find that glycoconjugates of myricetin and quercetin were the main flavonoids detected in the SF leaves extract. Meanwhile, phenolic acid was primarily exhibited to be gallic acid. Similarly, some triterpen aglycos were \begin{table}
\begin{tabular}{c c c c} \hline \hline
**No** & **Gene** & **Forward** & **Reverse** \\ \hline
1 & Actin & GGC GGA CTA CTA CTT AGT TG & AAC AAC AAC AAT GTG CAA TCA A \\
2 & IL-1g & GGG CCT CAA GGA AAA GAA TC & TTC TGC TTG AGA GGT GCT GA \\
3 & IL-6 & AGG AGA CTT GCC TGG TGA AA & CAG GGG TGC TTT ATG CAT CT \\
4 & IL-8 & TCT GTG TGA AGG TGC ACT T & AGC CCT CT CAA AAA CT CT \\
5 & COX-2 & GGT CTG GTG CCT GGT CCTG ATG & GTC CT TCA AGG AGA ATG GTG C \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Sequences of PCR primers of IL-19, IL-6, IL-8, COX-2, and a housekeeping gene, actin. predicted to be present in this material. For further confirmation, reference standards corresponding to expected compounds were purchased and simultaneously analyzed. In a mass spectroscopic analysis, positive-ion mode has been used for the analysis of flavonoid and triterpenod demonstration as more intense signals were achieved as the protonated molecular ions, [M+H]\({}^{+}\); in contrast, the negative-ion mode, [M-H]\({}^{-}\), was used for phenolic acids due to its fewer signals. The fragmentation of the expected compounds was conducted by product ion scan and the major fragment ions were selected based on their high intensity and were used under the multiple reaction monitoring (MRM) condition for quantitative analysis. Table 2 summarized the parameters of the compounds identified in _S. formosum_ leaves. Twenty components found in the SF leaf extract including eight flavonoids, three phenolic acids, and nine triterpenoids were confirmed based on a comparison of reference standards and MS/MS analysis (Figure 1, Supplementary Figures S1 and S2). MS/MS fragmentation of phenolic components and triterpenoids is presented in Supplementary Figure S3. We used both UV spectrometric and mass spectrometric methods to determine the phytochemicals in the SF leaves. To determine the major components of potential flavonoids and phenolics, a UV detector which coupled with mass spectrometry has been used at the wavelength of 370 nm. Then, the components were primarily identified by the molecular ion mass and fragmentation pattern at positive mode as well as the comparison of retention time with the reference standard. For example, a positive molecular ion at _m/z_ 291, and product ions at _m/z_ 139 and 123, were initially determined as catechin or its isomer epicatechin, then we confirmed it to be catechin based on the reference standard. Structural isomers could be determined by the MS/MS analysis without reference standards. By extraction of molecular ion mass of _m/z_ 435.1, three independent peaks were found at different retention time (Figure 1A). Among three peaks, one with the retention time of 6.79 min was identified as quercetin-arabinose by reference standard. Showing the unique fragmentation pattern in MS/MS spectra, two isobaric components were determined to be a quercetin-pentose glycogenjugate (Figure 1B). Those possibly could be a linkage isomer of quercetin-arabinose or different glycoconjugate such as quercetin-xylose. Similarly, when extracting molecular ion mass of _m/z_ 465.1, three peaks appeared at different time. Two among them with the retention time of 5.49 min and 6.02 min were confirmed to be myricetin-rhamnose and quercetin-glucose, respectively, based on a comparison of reference standards. By observing in MS/MS spectra, one remaining compound was glycogenjugate of quercetin with a hexose moiety. This compound could be