Hsin-Liang Chen

Bio-Functional Constituents from the Stems of Liriodendron tulipifera

Four known compounds have been isolated from the stems of Liriodendron tulipifera, and the structures of these pure constituents were determined using spectroscopic analysis. Isolated compounds were screened for free radical scavenging ability, metal chelating power assay and ferric reducing antioxidant power assay (FRAP). The anti-tyrosinase effects of L. tulipifera compounds were calculated the inhibition of hydroxylation of L-tyrosine to L-dopa according to an in vitro mushroom tyrosinase assay. The study also examined the bio-effects of the four compounds on the human melanoma A375.S2, and showed that liriodenine (1) and (-)-norglaucine (4) significantly inhibited the proliferation of melanoma cells in the cell viability assay. Wound healing results indicated that liriodenine (1), (-)-glaucine (3) and (-)-norglaucine (4) exerted anti-migration potential. Interestingly, (-)-glaucine (3), neither liriodenine (1) nor (-)-norglaucine (4) showed promising anti-migration potential without inducing significant cytotoxicity. Furthermore, a dramatically increased level of intracellular reactive oxygen species (ROS) was detected from (-)-glaucine (3). The cell cycle assessment demonstrated a moderate G2/M accumulation by (-)-glaucine (3). The above results revealed the anti-cancer effects of L. tulipifera compounds, especially on the anti-migration ability indicating the promising chemopreventive agents to human skin melanoma cells.

The Pharmacological Activities of (−)-Anonaine

Several species of Magnoliaceae and Annonaceae are used in Traditional Chinese Medicine. (−)-Anonaine, isolated from several species of Magnoliaceae and Annonaceae, presents antiplasmodial, antibacterial, antifungal, antioxidation, anticancer, antidepression, and vasorelaxant activity. This article provides an overview of the pharmacological functions of (−)-anonaine.

Review on pharmacological activities of Cinnamomum subavenium

This review describes the morphological, phytochemical and pharmacological properties of Cinnamomum subavenium (Lauraceae). The plant grows wild in southern Mainland China, Burma, Cambodia, Taiwan, Malaysia and Indonesia. This plant is recorded as having long been used to treat carcinomatous swelling, stomach ache, chest pain, abdominal pain, hernia, diarrhoea, rheumatism, nausea and vomiting. This article enumerates an overview of phytochemical and pharmacological aspects that is useful to researchers for further exploration for the necessary development of this potential herb.

Chemical Constituents of the Stems of Michelia champaca

Champacaine (1), (–)-anonaine (2), (–)-norushinsunine (3), (–)-ushinsunine (4), (–)-N-acetylanonaine (5), (–)-roemerine (6), (–)-asimilobine (7), (–)-anolobine (8), (–)-isocorydine (9), liriodenine (10), atherospermidine (11), O-methylmoschatoline (12), (+)-syringaresinol (13), N-trans-feruloyltyramine (14), 4-hydroxybenzaldehyde (15), vanillin (16), vanillic acid (17), syringic acid (18), 3,4-dimethoxybenzoic acid (19), coniferyl aldehyde (20), syringin (21), scopoletin (22), 4-acetonyl-3,5-dimethoxy-p-quinol (23), β-sitostenone (24), and stigmasta-4,22-dien-3-one (25) were isolated from the stems of Michelia champaca L. (Magnoliaceae). Among them, 1 is a new 4,5-dioxoaporphine compound. The structures of these compounds were characterized and identified by spectral analyses.

A new benzodioxocinone from the leaves of Cinnamomum tenuifolium

Investigation of the leaves’ extract of Cinnamomum tenuifolium (Lauraceae) led to the isolation of one novel benzodioxocinone, 2,3-dihydro-6,6-dimethylbenzo-[b][1,5]dioxocin-4(6 H)-one (1). The structure was determined through in-depth spectroscopic and mass-spectrometric analyses. The antioxidant potential was evaluated using the following in vitro method: scavenging of 1,1-diphenyl-2-picrylhydrazyl radical. We also detected the anti-proliferative effect of 1 on human oral cancer cells and its IC50 is 107.7 µM.

Secondary Metabolites from the Leaves of Aquilaria sinensis

Lignum Aquilariae Resinatum has been widely used in the treatment of various kinds of pain, cough, and anaphylaxis for hundreds of years in Asia, especially in China, Vietnam, and Indonesia. The genus Aquilaria (Thymelaeaceae) is widely distributed in Asia. Aquilaria sinensis Gilg is of particular interest economically because it is the principal source of agarwood, one of the most highly valued forest products currently traded internationally. The leaves of A. sinensis Gilg, which is widely cultivated in Guangdong, Hainan, and Taiwan Provinces in China, are reported to be used locally in trauma-related diseases such as fracture, bruise, etc. [1]. Previous phytochemical investigations on Chinese eaglewood have revealed characteristic sesquiterpenes and chromone derivatives [2–15] but few on the chemical constituents of the leaves [16, 17]. The analgesic and anti-inflammatory activities of the ethanol extract of A. sinensis leaves were observed in various experimental models related to nociception and inflammation, thus providing some evidence for its traditional use. In the investigations of interrelated studies, it was found that agarwood has significant anticancer activities [18], analgesic and anti-inflammatory activities [19], and anti-depressant activities [20, 21]. These observations provide useful information for potential chemopreventive drug design. The MeOH extract of its leaves were subjected to solvent partitioning and chromatographic separation to afford 12 pure substances. Twelve compounds, including three flavonoids, 5-hydroxy-4 ,7-dimethoxyflavonoid (1) [22], luteolin-7,3 ,4 -trimethyl ether (2) [23], and 5,3 -dihydroxy-7,4 -dimethoxyflavone (3) [24], five benzenoids, methylparaben (4) [25], vanillic acid (5) [26], p-hydroxybenzoic acid (6) [27], syringic acid (7) [28], and isovanillic acid (8) [28], and four steroids, -sitosterol (9) [29], stigmasterol (10) [29], -sitostenone (11) [29], and stigmasta-4,22-dien-3-one (12) [29], were isolated from the leaves of A. sinensis. All of these compounds (1–12) were obtained for the first time from the leaves of this plant. The specimen of A. sinensis was collected from Guansi Township, Hsinchu County, Taiwan in May, 2007. A voucher specimen was identified by Prof. Fu-Yuan Lu (Department of Forestry and Natural Resources, College of Agriculture, National Chiayi University) and was deposited in the School of Medical and Health Sciences, Fooyin University, Kaohsiung, Taiwan. The leaves (1.2 kg) of A. sinensis were air dried and extracted repeatedly with MeOH (6 L 8) at room temperature. The combined MeOH extracts (31.3 g) were then evaporated and further separated into four fractions by column chromatography on silica gel (4.3 kg, 70–230 mesh) with gradients of n-hexane–CH2Cl2–acetone–MeOH. Part of fraction 1 (11.6 g) was subjected to silica gel chromatography by eluting with n-hexane–acetone (50:1), enriched with acetone, to furnish three further fractions (1-1–1-3). Fraction 1-1 (2.8 g) was further purified on a silica gel column using n-hexane–acetone mixtures to obtain 5-hydroxy-4 ,7-dimethoxyflavonoid (1) (4.8 mg). Part of fraction 1-2 (2.5 g) was subjected to silica gel chromatography by eluting with n-hexane–acetone (50:1), enriched gradually with acetone, to furnish two fractions (1-2-1–1-2-2). Fraction 1-2-1 (0.5 g) was further purified on a silica gel column using n-hexane–acetone mixtures to yield luteolin-7, 3 ,4 -trimethyl ether (2) (3.4 mg) and 5,3 -dihydroxy-7,4 -dimethoxyflavone (3) (3.2 mg). Fraction 1-2-2 (0.5 g) was further purified on a

Chemical Constituents of Liriodendron tulipifera

dealt with several alkaloids andsesquiterpenes [3–11]. Previously, we have isolated three aporphines, one oxoaporphine, three lignans, ten benzenoids, andfour steroids from the leaves of this plant [12]. To further understand the chemotaxonomy and to continue searching forbiologically and chemically novel agents from

Secondary Metabolites from Nelumbo nucifera cv. Rosa-plena

Nelumbo nucifera Gaertn. cv. Rosa-plena is a perennial aquatic crop grown and consumed throughout Asia. All parts of N. nucifera have been used for various medicinal purposes in oriental medicine. In particular, the leaves are known for diuretic and astringent properties and are used to treat fever, sweating, and strangury, and as a styptic [1]. To further understand the chemotaxonomy of the Nelumbo species [1, 2], Nelumbo nucifera Gaertn. cv. Rosa-plena was chosen for phytochemical investigation. There is only one paper describing the constituents of this plant [3]. Previously, we have isolated seven aporphines, two oxoaporphines, one dioxoaporphine, one dehydroaporphine, two steroids, and two chlorophylls from this plant [3]. As part of our continuing investigation of the phytochemical and bioactive compounds of Nelumbo plants, seven flavonoids, quercetin [4], quercetin 3-O-D-glucopyranoside [5], quercetin 3-O-D-galactopyranoside [6], quercetin 3-O-Dglucopyranosyl-(1 6)-D-glucopyranoside [7], isorhamnetin [8], isorhamnetin 3-O-D-glucopyranoside [8], and isorhamnetin 3-O-D-galactopyranoside [8] were obtained by systematic extraction and isolation from the leaves of Nelumbo nucifera Gaertn. cv. Rosa-plena. All of these compounds were isolated for the first time from this source. The leaves of Nelumbo nucifera Gaertn. cv. Rosa-plena were collected from Tainan County, Taiwan, November 2008. Plant material was identified by Prof. Fu-Yuan Lu (Department of Forestry and Natural Resources College of Agriculture, National Chiayi University). A voucher specimen (Nelumbo nucifera Gaertn. cv. Rosa-plena) was deposited in the Department of Medical Laboratory Science and Biotechnology, School of Medical and Health Sciences, Fooyin University, Kaohsiung, Taiwan. The air-dried leaves of Nelumbo nucifera Gaertn. cv. Rosa-plena (1.5 kg) were extracted with MeOH (5 L 5) at room temperature, and a MeOH extract (108.7 g) was obtained upon concentration under reduced pressure. The MeOH extract, suspended in H2O (1 L), was partitioned with CHCl3 (3 L 4) to give fractions soluble in CHCl3 (57.23 g) and H2O (43.62 g). The CHCl3-soluble fraction was chromatographed over silica gel (1700 g, 70–230 mesh) using n-hexane–EtOAc– MeOH mixtures as eluents to produce six fractions. Part of fraction 5 (5.34 g) was subjected to silica gel chromatography by eluting with CH2Cl2–MeOH (40:1) and enriched with MeOH to furnish two fractions (5-1–5-2). Fraction 5-2 (1.67 g) was eluted with n-hexane–EtOAc mixtures to obtain isorhamnetin (2 mg). Part of fraction 6 (4.21 g) was subjected to silica gel chromatography by eluting with EtOAc–MeOH (20:1) and enriched with MeOH to furnish five further fractions (6-1–6-5). Fraction 6-1 (1.46 g) was subjected to silica gel chromatography by eluting with n-hexane–EtOAc (1:9) and enriched gradually with EtOAc to produce quercetin (5 mg). Fraction 6-2 (0.76 g) was subjected to silica gel chromatography by eluting with EtOAc–MeOH (30:1) and enriched gradually with MeOH to produce isorhamnetin 3-O-D-glucopyranoside (5 mg) and isorhamnetin 3-O-D-galactopyranoside (7 mg). Fraction 6-3 (1.51 g) was further purified on a silica gel column using EtOAc–MeOH mixtures to obtain quercetin 3-O-D-glucopyranoside (5 mg) and quercetin 3-O-D-galactopyranoside (4 mg). Fraction 6-4 (0.76 g) was eluted with EtOAc–MeOH (9:1) and repeatedly subjected to silica gel CC to give quercetin 3-O-D-glucopyranosyl-(1 6)-D-glucopyranoside (6 mg).

Secondary Metabolites from the Stems of Capsicum annuum var. longum

Red pepper, Capsicum annuum (Solanaceae), is used as a spice all over the world. Red pepper is studied actively because its pungent principal component, capsaicin, has a dietary effect and analgesic and antioxidant activity [1]. The pungent principal component of red peppers is a group of acid amides of vanillylamine and C8 to C13 fatty acids, which are known generally as capsaicin [2]. More than 16 other capsaicinoids have been found as minor components [3]. Numerous studies have been done on the red pepper fruit, but there are few studies on stems [2–4]. Earlier investigations on the chemical constituents of stems of C. annuum L. dealt with a new amide, 7 -(4 -hydroxyphenyl)-N-[(4-methoxyphenyl)-ethyl]propenamide, along with 13 known compounds [2]. The chemical constituents of stems of C. annuum L. var. longum Sendtn. cv. have not yet been reported, and this study shows their isolation. To further understand the chemotaxonomy and to continue searching for biologically and chemically novel agents from Solanaceous plants, the stems of C. annuum L. var. longum Sendtn. cv. were chosen for further phytochemical investigation. The MeOH extract of its plants was subjected to solvent partitioning and chromatographic separation to afford 19 pure substances. The chemical constituents in the plant of C. annuum L. var. longum Sendtn. cv. were separated with column chromatography. Investigation of the MeOH extract of the plants has led to the isolation of 19 compounds, including eight amides: N-trans-feruloyltyramine (1) [5], N-cis-feruloyltyramine (2) [6], N-trans-caffeoyltyramine (3) [5], N-cis-caffeoyltyramine (4) [7], N-p-trans-coumaroyltyramine (5) [8], N-p-cis-coumaroyltyramine (6) [8], cinnaretamine (7) [9], and cinnabutamine (8) [10]; four steroids: -sitosterol (9) [5], stigmasterol (10) [5], -sitostenone (11) [5], and stigmasta-4,22-dien-3-one (12) [5]; three lignans: (+)-syringaresinol (13) [11], (+)-dia-syringaresinol (14) [12], and threo-2,3-bis-(4-hydroxy-3-methoxyphenyl)3-methoxypropanol (15) [13]; three benzenoids: p-hydroxybenzoic acid (16) [14], p-hydroxybenzaldehyde (17) [14], and vanillic acid (18) [14]; and one ionone: (+)-abscisic acid (19) [15]. These compounds were obtained and characterized by comparison of their physical and spectral data (UV, IR, NMR, and MS) with values obtained in the literature. All of these compounds were found for the first time from this species. The specimen of C. annuum L. var. longum Sendtn. cv. was collected from Chiayi County, Taiwan in April, 2010. A voucher specimen was characterized by Dr. Jin-Cherng Huang of the Department of Forest Products Science and Furniture Engineering, National Chiayi University, Chiayi, Taiwan and deposited in the School of Medical and Health Sciences, Fooyin University, Kaohsiung County, Taiwan. The air-dried stems of C. annuum L. var. longum Sendtn. cv. (12.5 kg) were extracted with MeOH (30 L 6) at room temperature, and the MeOH extract (302.7 g) was obtained upon concentration under reduced pressure. The MeOH extract was chromatographed over silica gel using CH2Cl2–MeOH as eluent to produce 13 fractions. Part of fraction 3 (12.23 g) was subjected to silica gel column chromatography by eluting with n-hexane–acetone (60:1) to furnish 10 fractions (3-1–3-10). Fraction 3-3 (5.83 g) was further purified by another silica gel column using n-hexane–acetone (10:1) to obtain 16 (5 mg) and 17 (7 mg). Part of fraction 4 (14.56 g) was subjected to silica gel column chromatography by eluting with n-hexane–acetone (30:1), then enriched with acetone to furnish six fractions (4-1–4-6). Fraction 4-1 (5.45 g) eluted with n-hexane–EtOAc (30:1) was further separated using silica gel column chromatography and preparative TLC (n-hexane–EtOAc,

Chemical constituents from the stems of Machilus philippinensis

Machilus philippinensis Merr. (Lauraceae) is a medium-sized evergreen tree distributed at an altitude of 500 to 1600 m in Taiwan and the Philippines [1]. In continuation of some studies of chemotaxonomy and biologically active metabolites from Formosan Lauraceous plants [2–10], a methanol extraction of the stems of M. philippinensis afforded 10 known compounds, including three lignans: cinnamophilin (1) [11], erythro-austrobailignan (2) [12], (+)-syringaresinol (3) [13]; one amide: cinnaretamine (4) [4]; four benzenoids: p-hydroxybenzoic acid (5) [14], p-hydroxybenzadehyde (6) [14], vanillic acid (7) [14], p-anisaldehyde (8) [15]; and two steroids: -sitosterol (9) [16] and -sitostenone (10) [16]. In addition to cinnamophilin [11], all of these compounds were found for the first time from this plant. The stems of M. philippinensis were collected from Taiwan County in May 2008. Plant material was identified by Dr. Yen-Ray Hsui (Chungpu Research Center, Taiwan Forestry Research Institute). A voucher specimen has been deposited at the Department of Medical Technology, School of Medical and Health Sciences, Fooyin University, Kaohsiung, Taiwan. The stems (6.14 kg) of M. philippinensis were extracted repeatedly with MeOH at room temperature for 24–48 h. The MeOH extract was dried and evaporated to leave a viscous residue (425.8 g). The residue was placed on a silica gel column and eluted with CH2Cl2 gradually enriched with MeOH to afford 9 fractions. Part of fraction 1 (13.7 g) was subjected to silica gel chromatography by eluting with n-hexane–acetone (40:1) and enriched gradually with acetone to furnish three fractions (1-1–1-3). Fraction 1-1 (4.3 g) was further purified on a silica gel column using n-hexane–acetone mixtures to obtain -sitostenone (10, 12 mg). Fraction 1-2 (4.3 g) was further purified on a silica gel column using n-hexane–acetone mixtures to obtain -sitosterol (9, 10 mg) and p-hydroxybenzaldehyde (6, 5 mg). Fraction 1-3 (3.2 g) was further purified on a silica gel column using n-hexane–acetone mixtures to obtain erythro-austrobailignan (2, 13 mg). Part of fraction 4 (8.8 g) was subjected to silica gel chromatography by eluting with n-hexane–acetone (20:1) and enriched with acetone to furnish two further fractions (4-1–4-2). Fraction 4-1 (6.3 g) was further purified on a silica gel column using n-hexane–acetone mixtures to obtain cinnamophilin (1, 30 mg). Part of fraction 4-2 (2.3 g) was further purified on a silica gel column using n-hexane–acetone mixtures to obtain p-hydroxybenzoic acid (5, 4 mg). Part of fraction 7 (12.4 g) was subjected to silica gel chromatography by eluting with n-hexane–acetone (10:1) and enriched with acetone to furnish two further fractions (7-1–7-2). Fraction 7-1 (6.4 g) was further purified on a silica gel column using n-hexane–acetone mixtures to obtain vanillic acid (7, 18 mg). Part of fraction 8 (24.6 g) was subjected to silica gel chromatography by eluting with CH2Cl2–MeOH (100:1) and enriched with MeOH to furnish three fractions (8-1–8-3). Fraction 8-2 (10.3 g) was further purified on a silica gel column using CHCl3–MeOH mixtures to obtain (+)-syringaresinol (3, 10 mg). Fraction 8-3 (7.3 g), eluted with CHCl3–MeOH (60:1), was further separated using silica gel column chromatography and preparative TLC (CHCl3–MeOH 100:1) and gave cinnaretamine (4, 5 mg). Fraction 9 (6.4 g) eluted with CHCl3–MeOH (50:1) was further separated using silica gel column chromatography and preparative TLC (CHCl3–MeOH 15:1) to give p-anisaldehyde (8, 22 mg).