547.918Synsepalum dulcificum Daniell (Sapotaceae) is an evergreen shrub native to tropical West Africa, and the fruits, and red berries have the property of modifying sour taste into sweet taste remarkably. Interestingly, the active material of the berry is the protein, miraculin, which has no taste in itself. The sweetness intensity induced by 0.02 M citric acid after 0.4 M purified miraculin solution is held in the mouth is equivalent to that of about 0.3 M sucrose. This value is equal to the maximum sweetness induced by miraculin [1].The specimen of S. dulcificum was collected from Kaohsiung County, Taiwan, October 2007. A voucher specimen was identified by Dr. 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 Science, The Fooyin University, Kaohsiung County, Taiwan. The stems (5.0 kg) of S. dulcificum were extracted repeatedly with MeOH at room temperature for 24-48 h. The MeOH extract was dried and evaporated to leave a viscous residue (102.3 g). The residue was placed on a silica gel column and eluted with CHCl 3 gradually enriched with MeOH to afford 10 fractions. Fraction 3 was rechromatographed on silica gel (n-hexane-EtOAc, 20:1) and recrystallized from EtOAc to give a mixture of E-sitosterol (1) and stigmasterol (2) (317.2 mg). Fraction 4, eluted from n-hexane-EtOAc (1:2), was further chromatographed on silica gel elution with EtOAc-MeOH (15:1) and recrystallized from acetone to give pheophytin-a (3) (21.4 mg) and pheophytin-b (4) (15.8 mg), respectively. Fraction 5 was purified by silica gel chromatography (EtOAc-MeOH, 40:1) to give colorless needles of lupeol (5) (321.5 mg). Fraction 6 was purified by silica gel chromatography (EtOAc-MeOH, 8:1) to give colorless needles of lupenone (6) (51.4 mg) and lupeol acetate (7) (21.1 mg). Fraction 7 was purified by silica gel chromatography (CHCl 3 -MeOH, 40:1) to give D-tocopheryl quinone (8) (52.4 mg).The MeOH extract of its leaves was subjected to solvent partitioning and chromatographic separation to afford five pure substances. The chemical constituents of the leaves of S. dulcificum were separated with column chromatography. Eight compounds, including, a mixture of E-sitosterol (1) and stigmasterol (2) [2], pheophytin-a (3) [3], pheophytin-b (4) [3], lupeol (5) [4], lupenone (6) [5], lupeol acetate (7) [6], and D-tocopheryl quinone (8) [7], were isolated from the leaves of S. dulcificum. All of these compounds were found for the first time from this plant. ACKNOWLEDGMENT
syringaldehyde (3), trans-coumaric acid (4), cis-coumaric acid (5), vanillic acid (6), and p-hydroxybenzoic acid (7), were isolated from the leaves of Cinnamomum subavenium Miq (Lauraceae). These compounds were identified and characterized by physical and spectral evidence.
547.918Leucaena leucocephala (Leguminosea) is a small, leguminous plant native to tropical America, now widely distributed in southern Asia and neighboring islands [1]. Previous studies have show that gallocatechin, epigallocatechin, catechin, and epicatechin extracted from the roots of L. leucocephala exhibit nitrification inhibition against the bacterium Nitrosomonas europaea [2]. L. leucocephala was chosen for further phytochemical investigation. The MeOH extract of its plants was subjected to solvent partitioning and chromatographic separation to afford 14 pure substances. The chemical constituents in the plants of L. leucocephala were separated by column chromatography.Investigation on the MeOH extract of the plants has led to the isolation of 14 compounds. These are four steroids: 5D,8D-epidioxy-(24[)-ergosta-6,22-dien-3E-ol (1) [3], E-sitosterol (2) [4], E-sitostenone (3), and stigmastenone (4) [5]; one triterpenoid: lupeol (5) [6]; one glyceride: 1,3-dipalmitoyl-2-oleoylglycerol (6) [7]; one alkaloid: linoleic acid (7) [8]; two benzenoids: methylparaben (8) [9] and isovanillic acid (9) [10]; and five chlorophylls: pheophytin-a (10) [11], pheophorbide a methyl ester (11) [12], methyl-13 2 -hydroxy-(13 2 -S)-pheophorbide-b (12) [13], 13 2 -hydroxy-(13 2 -S)-pheophytin-a (13) [14], and aristophyll-C (14) [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. Among them, 1-9 were found for the first time from the species. The air-dried seeds of L. leucocephala (2.1 kg) were extracted with MeOH (80 L u 6) at room temperature, and the MeOH extract (162.5 g) was obtained upon concentration under reduced pressure. The MeOH extract was chromatographed over silica gel (800 g, 70~230 mesh) using n-hexane-acetone as eluent to produce 5 fractions. Part of fraction 1 (6.11 g) was subjected to Si gel chromatography by eluting with n-hexane-acetone (40:1), enriched with acetone to furnish 10 fractions (1-1-1-10). Fraction 1-1 (1.72 g) was resubjected to Si gel chromatography by eluting with n-hexane-acetone (80:1) to obtain linoleic acid (7) (58 mg, 0.0357%). Part of fraction 3 (6.94 g) was subjected to Si gel chromatography by eluting with n-hexane-acetone (50:1) to obtain E-sitosterol (2) (15 mg, 0.0092%). Part of fraction 4 (6.77 g) was subjected to Si gel chromatography by eluting with n-hexane-acetone (8:1), then enriched with acetone to furnish 7 fractions (4-1-4-7). Fraction 4-5 (0.62 g) was further purified by another silica gel column using n-hexane-acetone to obtain methylparaben (8) (8 mg, 0.0049%) and isovanillic acid (9) (12 mg, 0.0074%).The air-dried brown beans of L. leucocephala (3.2 kg) were extracted with MeOH (80 L u 6) at room temperature, and the MeOH extract (171.5 g) was obtained upon concentration under reduced pressure. The MeOH extract was chromatographed over silica gel using n-hexane-acetone as eluent to produce 6 fractions. Part of fraction 1 (7.02 g) was subjected to Si gel chromato...
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