Chemical Constituents and Anti-influenza Viral Activity of the Leaves of Vietnamese Plant Elaeocarpus tonkinensis
Nga Thu Dao, Yejin Jang, Meehyein Kim, Hung Huy Nguyen, Duong Quang Pham, Quang Le Dang, Minh Van Nguyen,
Bong-Sik Yun, Quan Minh Pham, Jin-Cheol Kim and Vu Dinh Hoang
School of Chemical Engineering, Hanoi University of Science and Technology, Hanoi, 10000, Vietnam
Virus Research Group, Korea Research Institute of Chemical Technology, Gajeong-ro, Yuseong-gu, Daejeon 34114, Korea
Center for Advanced Chemistry, Duy Tan University, Da Nang 55000, Vietnam
Center for High Technology Development, Vietnam Academy of Science and Technology, Hanoi 10000, Vietnam
R&D Center of Bioactive Compounds, Vietnam Institute of Industrial Chemistry, Hanoi, 10000, Vietnam
Division of Biotechnology, College of Environmental and Bioresource Sciences, Chonbuk National University, Jeonju-si, Jeollabuk-do 54896, Korea
Institute of Natural Products Chemistry, Vietnam Academy of Science and Technology
Department of Agricultural Chemistry, Institute of Environmentally Friendly Agriculture, College of Agriculture and Life Sciences, Chonnam National University, Gwangju 61186,Korea
Abstract: Various Elaeocarpus species including Elaeocarpus tonkinensis have been important medicinal plants that used in traditional medication system and mainly used to cure nervous system-related disorders. However, their antiviral potential has not been reported yet. During the screening of medicinal plant extracts with the antiviral activity against influenza viruses, we found that E. tonkinensis extract has strong antiviral activity. Through organic solvent partition and repeated column chromatography using SiO 2, C-18 and Sephadex LH-20, a total of nine compounds were purified from the methanol extract of E. tonkinensis. Their chemical structures were determined by NMR and MS spectral data to be trolliamide (1), gallic acid (2), urolithin M-5 (3), hydroquinone (4), 2,4-dihydroxybenzoic acid (5), 3,5-dihydroxy-4-methoxybenzoic acid (6), corilagin (7), chebulagic acid (8), and shikimic acid (9). Their antiviral activity against influenza virus strains A/Puerto Rico/8/34 (H1N1; PR8), A/Hong Kong/8/68 (H3N2; HK) and B/Lee/40 (Lee) was examined on the basis of cytopathic effect (CPE) assay. Among them, compounds 2, 3, 4, 7, and 8 significantly inhibited viral replication in a dose-dependent manner with EC 50 values ranging from 7.8 to 59.6 μg/mL against influenza A and/or B viruses with selectivity indices above 5.0. This study suggests that the botanical materials of E. tonkinensis could be promising inhibitors of influenza A andB viruses and applied to the development of a novel herbal medicine.
Keywords: Influenza virus; Elaeocarpus tonkinensi;antiviral activity; infectious disease . © 2018 ACG Publications. All rights reserved.