ABSTRACT
Four new indole alkaloids (1-4) and twenty known compounds (5-24) were isolated from the leaves and stems, and fruits of Kopsia officinalis. Their structures were confirmed by means of spectroscopic methods. All these isolates were evaluated for their antagonizing high glucose-evoked podocyte injury activity for the first time, and compounds 5-8 showed potent activity with EC50 values of 3.0-12.0⯵M.
Subject(s)
Apocynaceae/chemistry , Indole Alkaloids/pharmacology , Podocytes/drug effects , Animals , Cells, Cultured , China , Fruit/chemistry , Glucose , Indole Alkaloids/isolation & purification , Mice , Molecular Structure , Phytochemicals/isolation & purification , Phytochemicals/pharmacology , Plant Leaves/chemistry , Plant Stems/chemistryABSTRACT
Magnetic N-doped carbon nanotubes were firstly applied as adsorbent in food analysis for pre-concentration of bisphenols in fruit juices followed by ultra-high performance liquid chromatography-tandem mass spectrometry determination. The magnetic nanoparticles were characterized by X-ray diffraction, infrared spectroscopy, scanning electron microscopy and vibrating sample magnetometer. The adsorption conditions were further optimized by response surface methodology. Under optimal conditions, the method provided good linearity with correlation coefficient (râ¯≥â¯0.9979), excellent intermediate precisions (2.71-5.91%, nâ¯=â¯3), low limits of detection (LODs) ranging from 0.43 to 2.47â¯ngâ¯L-1, and satisfying recoveries of three juice samples (between 90.6% and 101%).
Subject(s)
Chromatography, High Pressure Liquid/methods , Fruit and Vegetable Juices/analysis , Magnetics , Nanotubes, Carbon/chemistry , Solid Phase Extraction/methods , Adsorption , Limit of DetectionABSTRACT
Three new indole alkaloids, named kopsioffines A-C (1-3), possessing relatively novel ten-membered lactam ring, and one known compound (11,12-demethoxy-16-deoxypauciflorine, 4) were isolated from the leaves and stems of Kopsia officinalis. Their structures were elucidated by means of spectroscopic methods. The absolute configuration of 1 was determined by calculated electronic circular dichroism data. The hypothetical biosynthetic pathway of 1 was postulated. All these isolates were evaluated for their inhibitory effects on α-glucosidase. None of them showed activity with IC50 far beyond 50µM.
Subject(s)
Apocynaceae/chemistry , Indole Alkaloids/isolation & purification , Glycoside Hydrolase Inhibitors/chemistry , Glycoside Hydrolase Inhibitors/isolation & purification , Indole Alkaloids/chemistry , Molecular Structure , Plant Leaves/chemistry , Plant Stems/chemistry , alpha-GlucosidasesABSTRACT
Two new monoterpenoid indole alkaloids, melaxillines A (1) and B (2), together with four known alkaloids (3-6), were isolated from the roots of Melodinus axillaris. The structures were determined by extensive spectroscopic methods, including 1D and 2D-NMR spectroscopy, high resolution mass spectrometric data, and by comparison to literature data. New compounds 1-2 might be derived from a common precursor (3) by proposing their biogenetic route, and compound 1 represents the first Melodinus alkaloid featuring an ethyl acetate group skeleton at C-18. The anti-inflammatory effects of all the isolated compounds were evaluated by measuring the inhibitory ratios of ß-glucuronidase release in rat polymorphonuclear leukocytes (PMNs) induced by platelet-activating factor. Compounds 1-4 showed significant anti-inflammatory activities with IC50 values ranging from 1.51 to 21.56µM, respectively.
