## 5 Conclusions  
In this study, the detailed phytochemical profiling of _S. formosum_ leaves was conducted. Our results showed that this plant contains valuable secondary metabolites including eight flavonoids, three phenolic acids, and nine triterpenoids. Our study is the first report involving the quantitative analysis of functional phytochemicals identified in the ethanolic extracts of _S. formosum_ leaves as well as comparative analysis with the ethanolic extracts of _C. asiatica_ leaves derived from Indonesia and Korea. The total content of functional phytochemical groups in the SF leaves was significantly higher than that in _C. asiatica_ leaves. The high content of bioactive compounds in the SF leaves as well as the exhibition of biological functionalities of the SF leaves such as anti-inflammatory and antibacterial effects can explain its traditional use for the treatment of some skin-related diseases in Vietnam. _S. formosum_ could be a promising potential candidate for cosmetic and pharmacological applications in the future. The following are available online at [[https://www.mdpi.com/article/10.3390/app112210552/s1](https://www.mdpi.com/article/10.3390/app112210552/s1)]([https://www.mdpi.com/article/10.3390/app112210552/s1](https://www.mdpi.com/article/10.3390/app112210552/s1)), Table S1: The MRM parameters and MS/MS transitions for analysis of phenolic compounds and triterpenoids; Table S2: Regression equations and coefficients, linear ranges, limit of detection, limit of quantification, and recovery of the analytes; Figure S1: The MRM chromatogram of detected phenolic acids in _Syzygium formosum_ leaves (A: Mixed standard, B: Sample;1-Gallic acid, 2-3,4-dihydrobenzoic acid, 3-p-coumaric acid)_; Figure S2: The MRM chromatogram of detected triterpenenoids in _Syzygium formosum_ leaves (A: Mixed standard, B: Sample; _1-Macdassic acid_, _2-Asiatic acid_, 3-Hederagenin, 4-Maslinic acid, 5-Crosolic acid, 6-Betulin, 7-Betulinic acid, 8-Oleanolic acid, 9-Ursloc acid)_; Figure S3: Proposed fragmentation of phenolic compounds (A) and triterpenenoids (B and C) in _Syzygium formosum_ leaves. Data curation, M.T.T.N. ; Formal analysis, J.L., M.T.T.N. and H.-L.K. ; Funding acquisition, C.-K.L. ; Investigation, K.H.T.H. and N.-Y.L. ; Project administration, J.K.; Resources, C.-K.L. and V.D.N. ; Supervision, J.-T.P. ; Writing--original draft, K.H.T.H. ; Writing--review and editing, J.-T.P. and J.K. All authors have read and agreed to the published version of the manuscript. This research was supported by a grant of the Korea Health Technology R&D Project through the Korea Health Industry Development Institute (KHIDI), funded by the Ministry of Health & Welfare, Republic of Korea (grant number: HP20C0211). Not applicable. The authors declare no conflict of interest. * [PERSON] et al. (2016) [PERSON]; [PERSON]; [PERSON]; [PERSON] Evaluation of the topical spray containing Centella asaatica extract and efficacy on excision wounds in rats. _Acta Pharm._**2016**, _66_, 233-244. [CrossRef] [PubMed]
* [PERSON] and [PERSON] (2019) [PERSON]; [PERSON] Improving cosmetic activity by optimizing Centella asaatica extraction process. _Nat. Prod. Commun._**2019**, _14_, 1934578X19867188. [CrossRef]
* [PERSON] et al. (2016) [PERSON]; [PERSON]; [PERSON] Moisturizing and antiinflammatory properties of cosmetic formulations containing Centella asaatica extract. _Indian J. Pharm. Sci._**2016**, _78_, 27. [CrossRef]
* [PERSON] et al. (2014) [PERSON]; [PERSON]; [PERSON]; [PERSON] Preliminary phytochemical screening of six medicinal plants used in traditional medicine. _Int. J. Pharm. Pharm. Sci._**2014**, \(6\), 539-542. * [PERSON] and [PERSON] (2019) [PERSON]; [PERSON] _Chemistry for Pharmacy Students: General, Organic and Natural Product Chemistry_; John Wiley & Sons: Hoboken, NJ, USA, 2019. * [PERSON] et al. (2015) [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON] Antioxidant and anticholinesterase investigations of Rumex hastatus D. Don: Potential effectiveness in oxidative stress and neurological disorders. _Biol. Res._**2015**, _48_, 20.