Chemical constituents from the leaves of Synsepalum dulcificum

Abstract

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

Antibacterial Property of Synsepalum dulcificum Leaves Aqueous Extract against Oral Pathogens and its Chemical Compounds

“…Its phytochemical compounds were also analysed since the region of plantation might contribute to the phytochemical discrepancy. The previous studies of methanol extract of S. dulcificum leaves collected from two countries showed that the chemical compounds were different (Chen et al, 2010;Obafemi et al, 2017b). In the present study, the chemical compounds of S. dulcificum leaves was analysed by gas chromatographymass spectrometry (GC-MS) because this technique is highly sensitive, fast and no standards are needed since the identification of the chemical compounds was carried out by comparing the mass spectra with the libraries (Hübschmann, 2015).…”

“…Although steroid was identified in small percentage, this compound was not identified in methanol extract of S. dulcificum leaves obtained in Nigeria (Obafemi et al, 2017b). On the other hand, methanol extract of S. dulcificum leaves collected in Taiwan showed the presence of steroids such as β-sitosterol and stigmasterol (Chen et al, 2010). This finding showed that the cultivation area might influence the chemical compounds of the S. dulcificum.…”

Radical Scavenging activity and phytochemical screening of the leaf extract of Synsepalum dulcificum (Schumach. & Thonn.) Daniell

“…The flowers are white with about 2-2.5 cm long fruits and gives red colour when ripe; each fruit contains one seed [6]. The active component present in the berry is the glycoprotein called miraculin which has no taste in itself [7]. When the fruit pulp is licked, it miraculously turns sour foods such as limes, lemons, vinegar etc.…”

Secondary metabolites from the stems of Synsepalum dulcificum

“…This explains why the berry has been called "miracle fruit or mysterious fruit". In the course of screening for chemically novel agents from plants, S. dulcificum was chosen for further phytochemical investigation [2][3][4][5]. In this study, the MeOH extract of its stems was subjected to chromatographic separation to afford six pure compounds, including propane-1,2,3-triol (1), 2,5-dimethoxyphenol (2), 3,4,5-trimethoxybenzoic acid (3), nicotinic acid (4) [6], E-sitosterol (5), and stigmasterol (6) [7].…”

“…In this study, the MeOH extract of its stems was subjected to chromatographic separation to afford six pure compounds, including propane-1,2,3-triol (1), 2,5-dimethoxyphenol (2), 3,4,5-trimethoxybenzoic acid (3), nicotinic acid (4) [6], E-sitosterol (5), and stigmasterol (6) [7]. Among them, 2 was isolated from natural sources for the first time though they had been synthesized previously [8], and 1-4 were obtained for the first time from this plant [2][3][4][5]. In this paper, we report the isolation and structure elucidation of 2.…”