Search

The polar and non-polar extracts from the authenticated wild mushroom Phylloporia ribis were separated by hydrophilic interaction liquid chromatography (HILIC) and by reverse phase (RP)-HPLC, respectively. A split valve separated the eluents into two fractions for free-radical scavenging analysis and for structural identification. Forty-six compounds showed scavenging activity of the stable-free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH). The structures of 8 antioxidants (inosine, caffeic acid, ergothioneine, p-hydroxybenzoic acid, adenosine, 3,4-dihydroxybenzaldehyde, apigenin, and naringenin) are characterized by Mass Spectrometer. Among them, ergothioneine was the most abundant (>65%) and most active antioxidant in P. ribis. [ABSTRACT FROM AUTHOR]

In this work, six coumarins, including two new ones, 8-(3-hydroxy-2,2-dimethylpropyl)-7-methoxy-2H-chromen-2-one (2) and 5-[(7′,8′-dihydroxy-3′,8′-dimethyl-2-nonadienyl)oxy] psoralen (4), as well as four known ones, 5-[(6′,7′-dihydroxy-3′,7′-dimethyl-2-octenyl) oxy] psoralen (1), marmin (3), epoxybergamottin (5), and aurapten (6) were successfully separated from the crude extract of pummelo (Citrus maxima(Burm.) Merr. Cv. Shatian Yu) peel by high-speed countercurrent chromatography in a single run with petroleum-ether–ethyl acetate–methanol–water (4:6:6:4, v/v). The structures of these six coumarins were elucidated by ESI-MS, extensive 1D and 2D NMR spectroscopy. [ABSTRACT FROM PUBLISHER]

The bulb ofLycoris radiataas a traditional folk medicine is well known for its biological activities and has been used for the treatment of many diseases. The major chemical ingredients of this herb are alkaloids including lycoramine, galantamine, and so on. In order to further articulate the pharmacological activities of the herb, relatively purified alkaloids are needed. Therefore, a rapid and efficient method for the isolation and purification of these alkaloids from the bulb of Lycoris radiata is of great interest. We herein report a new technique pH-zone-refining counter-current chromatography (CCC) combined with preparative high-performance liquid chromatography (HPLC) for the isolation and purification of these active ingredients. Although the conventional high-speed HSCCC method for the successful separation of the alkaloids fromLycoris radiatahas been reported, only two alkaloids are obtained. In the present study, seven alkaloids all with a purity of over 95% are successfully separated using this combinative technique. And the sample loading capacity is increased by 150-fold compared with that mentioned in the literature. Therefore, the combinative application of pH-zone-refining CCC and preparative HPLC is a rapid and efficient method for the separation and purification of natural compounds. [ABSTRACT FROM AUTHOR]

A rapid micellar extraction and pre-concentration method by ultrahigh pressure-assisted was developed for four alkaloids inNelumbo nuciferaleaves. Nonionic surfactant polyoxyethylene octylphenol ether (OP-10) solution was selected as solvent. Various experimental conditions were investigated to optimize the extraction and pre-concentration process. The optimal UPE condition was 5% OP-10 (w/w) solution, 400 MPa of pressure, 1 min of extraction time, and 1:20 (g/mL) of solid/liquid ratio. The pre-concentration of alkaloids was achieved by cloud-point extraction (CPE) and the optimum CPE condition was incubated in a thermostatic water bath at 55°C for 10 min, with 10% OP-10 and 15% sodium chloride added into the solution. The pre-concentration factor (CF) value was 11.6 ± 0.127, and the CPE recoveries forO-nornuciferine,N-nornuciferine, nuciferine, and roemerine were 91.0%, 92.3%, 92.7%, and 94.5%, respectively. [ABSTRACT FROM PUBLISHER]

Enrichment and separation of alkaloids from a chloroform extract of Sinomenium acutum has been successfully performed for the first time using pH-zone-refining counter-current chromatography. The two-phase solvent system used for enrichment was composed of Methyl tert-butyl ether (MtBE)-acetonitrile (CH3CN)-water (4:1:5, v/v), where 10 mM triethylamine (TEA) was added to the upper organic stationary phase as a retainer and 10 mM hydrochloric acid (HCl) to the aqueous mobile phase as an eluter, which could enrich the alkaloids from the crude extract well. For the preparative separation, the solvent system consisted of MtBE-CH3CN-water (4:0.5:5, v/v) with 10 mM TEA in organic stationary phase and 5 mM HCl in the aqueous mobile phase, which could separate and purify the enriched crude alkaloids successfully. 0.82 g of crude alkaloids was enriched from 1.60 g of chloroform extract in the first step separation. From the enriched crude alkaloids, 376 mg of sinomenine and 85 mg of acutumine were obtained in the second step separation with the purity of 98.1% and 98.7%, respectively. The chemical structures of the isolated compounds were identified by UV, ESI-MS and 1H NMR. [ABSTRACT FROM AUTHOR]