Studies on the Chemical Constituents and Biological Activities of the Leaves of Eriobotrya japonica

• Main Authors: CHIEN, LI-ER, 簡麗娥
• Other Authors: CHEN, JIH-JUNG
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/9pqnsp

碩士 === 大仁科技大學 === 製藥科技研究所 === 104 === Eriobotrya japonica (Thunb.) Lindl. (Rosaceae) is an small evergreen tree, distributed in China and Japan. In our studies on the anti-inflammatory constituents of Formosan plants, many species have been screened for in vitro anti-inflammatory activity, and E. japonica was found to be one of the active species. In our search for compounds with anti-inflammatory activities, three new triterpenoids, methyl 2α-O-(E)-p-methoxycinnamoyl-3β-hydroxy-urs-12-en-28-oate (1), methyl 2α-O-(E)-p-methoxycinnamoylpomolate (2), methyl 2α-O-(E)-3′,4′-dimethoxycinnamoylpomolate (3), and 12 known compounds (4–15) have been isolated and identified from the leaves of E. japonica. Twelve known compounds include eight triterpenoids, ursolic acid (4), methyl ursolate (5), 3β-O-trans-ferulyl-2α-hydroxy-urs-12-en-28-oic acid (6), methyl pomolate (7), methyl 2α,3α-dihydroxy-urs-12-en-28-oate (8), oleanolic acid (9), uvaol (10), and 11-oxo-ursolic acid methyl ester (11), and four steroids, mixture of β-sitostenone (12) and stigmasta-4,22-dien-3-one (13) and mixture of 6β-hydroxystigmast-4-en-3-one (14) and 6β-hydroxystigmasta-4,22-dien-3-one (15). The structures of all isolates were determined through spectral analyses and comparison of their physical and spectral data with literatures. Among the isolated compounds, ursolic acid (4) and oleanolic acid (9) exhibited inhibition (IC50 values ≤ 5.10 μg/mL) of superoxide anion generation by human neutrophils in response to N-formyl-L-methionyl-L-leuckyl-L-phenylalanine/cytochalasin B (fMLP/CB). In addition, methyl 2α-O-(E)-p-methoxycinnamoyl-3β-hydroxy-urs-12-en-28-oate (1), ursolic acid (4), methyl 2α,3α-dihydroxy-urs-12-en-28-oate (8), oleanolic acid (9), and uvaol (10) inhibited fMLP/CB-induced elastase release with IC50 values ≤ 5.44 μg/mL.