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Major Alkaloid (major + alkaloid)
Selected AbstractsIdentification of Major Alkaloids in Rat Urine by HPLC/DAD/ESI-MS/MS Method Following Oral Administration of Cortex Phellodendri DecoctionHELVETICA CHIMICA ACTA, Issue 2 2009Chun-Hui Ma Abstract A rapid, sensitive, and specific high-performance liquid chromatography (HPLC), diode-array detection, and mass-spectrometry techniques were developed for an identification of the constituents of Cortex Phellodendri and their metabolites in rat urine. The dose of 10,ml/kg of Cortex Phellodendri decoction was used for rats' oral administration. 0,24-h Urine was purified using a C18 solid-phase extraction cartridge, and then analyzed by an on-line MS detector. A total of 13,characteristic HPLC peaks were detected in the urine samples. Nine of them, including five alkaloids and four of their metabolites, were tentatively elucidated as magnoflorine (1), the glucuronide conjugate of demethyleneberberine (2), menisperine (3), jatrorrhizine 3- O -glucuronide (4), berberubine 9- O -glucuronide (5), jatrorrhizine (6), the monomethyl and monohydroxy catabolite of berberubine (7), palmatine (8), and berberine (9). Identification and structural elucidation of the metabolites were performed by comparing their MSn spectra data with those reported. [source] A convenient racemic synthesis of two isomeric tetrahydropyridyl alkaloids: Isoanatabine and anatabineJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 3 2010Anne Rouchaud Anatabine is a major alkaloid in Nicotiana tabacum and its isomer, isoanatabine, was recently found in a marine worm. Reduction of 1-methylpyridinium iodide with sodium borohydride gave 1-methyl-3-piperideine, which was transformed with hydrogen peroxide into the N -oxide. Reaction of the N -oxide successively with trifluoroacetic anhydride and potassium cyanide gave 2-cyano-1-methyl-3-piperideine. Its reaction with 3-pyridylmagnesium chloride gave (±)- N- methyl-isoanatabine. This was transformed with m -chloroperbenzoic acid into the N -oxide which was N -demethylated with iron(II) sulfate, giving (±)-isoanatabine. The successive applications of literature procedures for the N -demethylation by decomposition of N -oxide contributed to the knowledge of the mechanism of this oxidative rearrangement. On the other hand, the reduction of 1-methylpyridinium iodide with sodium borohydride and with potassium cyanide present since the start of the reaction in a two layer ether-water system, gave 2-cyano-1-methyl-4-piperideine. This was transformed into (±)-anatabine by the same sequence of reactions used for the synthesis of (±)-isoanatabine. J. Heterocyclic Chem., (2010). [source] Effects of areca nut extracts on the functions of human neutrophils in vitroJOURNAL OF PERIODONTAL RESEARCH, Issue 4 2000Shan-Ling Hung Aqueous extracts of ripe areca nut without husk (ripe ANE) and fresh and tender areca nut with husk (tender ANE) were examined for their effects on the defensive functions of human neutrophils. Exposure of peripheral blood neutrophils to ripe ANE and tender ANE inhibited their bactericidal activity against oral pathogens, including Actinobacillus actinomycetemcomitans and Streptococcus mutans, in a dose-dependent manner. At the concentrations tested, ripe and tender ANEs did not significantly affect the viability of neutrophils as verified by their ability to exclude trypan blue dye. However, both ANEs inhibited the production of bactericidal superoxide anion by neutrophils as measured by cytochrome c reduction. Moreover, the ripe ANE inhibited neutrophils more effectively than did tender ANE. Arecoline, a major alkaloid of areca nut, only exhibited an inhibitory effect on the functions of neutrophils when high concentrations were used. Therefore, arecoline could not be used to explain the inhibitory effects observed for ANEs. In conclusion, our results demonstrated that ripe and tender ANEs reduced the antibacterial activity and the superoxide anion production of neutrophils. This effect may contribute to a less efficient elimination of bacteria from the periodontal environment. Inhibition of the antimicrobial functions of neutrophils may alter the microbial ecology of the oral cavity, and this may be one possible mechanism by which areca nut compromises the oral health of users of areca nut products. [source] Systemic Administration of Arecoline Reduces Ethanol-Induced Sleeping Through Activation of Central Muscarinic Receptor in MiceALCOHOLISM, Issue 1 2010Yan-Ping Sun Background:, Epidemiological evidence of co-use of alcohol and areca nuts suggests a potential central interaction between arecoline, a major alkaloid of areca and a muscarinic receptor agonist, and ethanol. Moreover, the central cholinergic system plays an important role in the depressant action of ethanol and barbiturates. The purpose of this study was to investigate the effects of arecoline on pentobarbital- and ethanol-induced hypnosis in mice. Methods:, Male ICR mice were tested for locomotor activity following acute systemic administration of ethanol alone, arecoline alone, or ethanol plus arecoline. For the loss of the righting reflex (LORR) induced by pentobarbital and ethanol, sleep latency and sleeping duration were evaluated in mice treated with arecoline alone or the combination of arecoline and scopolamine or methscopolamine. Results:, Ethanol (1.0 to 3.0 g/kg, i.p.) reduced locomotor activity significantly and a declining trend was observed after treatment with arecoline (0.25 to 1.0 mg/kg, i.p.), but there were no synergistic effects of ethanol and arecoline on locomotor activity. The experiments on LORR demonstrated that arecoline (0.125 to 1.0 mg/kg, s.c.) shortened the duration of sleeping induced by ethanol (4.0 g/kg, i.p.), but not pentobarbital (45 mg/kg, i.p.). In addition, alterations of sleep latency were not obvious in both pentobarbital- and ethanol-induced LORR. Statistical analyses revealed that scopolamine (centrally acting), but not methscopolamine (peripherally acting), could antagonize the effect of arecoline on the duration of ethanol-induced LORR in mice. Conclusions:, These results suggest that central muscarinic receptor is a pharmacological target for the action of arecoline to modulate ethanol-induced hypnosis. [source] Photochemistry and Photocytotoxicity of Alkaloids from Goldenseal (Hydrastis canadensis L.) 3: Effect on Human Lens and Retinal Pigment Epithelial CellsPHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 4 2007Colin F. Chignell ABSTRACT The dried root or rhizome of Goldenseal (Hydrastis canadensis L.) contains several alkaloids including berberine, hydrastine, palmatine and lesser amounts of canadine and hydrastinine. Preparations derived from Goldenseal have been used to treat skin and eye ailments. Berberine, the major alkaloid in Goldenseal root powder, has been used in eye drops to treat trachoma, a disease characterized by keratoconjunctivitis. Berberine and palmatine are also present in extracts from Berberis amurensis Ruprecht (Berberidaceae) which are used to treat ocular disorders. We have previously shown that Goldenseal alkaloids are phototoxic to keratinocytes (Chem Res Toxicol. 14, 1529, 2001; ibid 19, 739, 2006) and now report their effect on human lens and retinal pigment epithelial cells. Human lens epithelial cells (HLE-B3) were severely damaged when incubated with berberine (25 ,M) and exposed to UVA (5 J cm,2). Under the same conditions, palmatine was less phototoxic and hydrastine, canadine and hydrastinine were inactive. Moderate protection against berberine phototoxicity was afforded by the antioxidants ascorbate (2 mM) and N -acetylcysteine (5 mM). When exposed to UVA (5 J cm,2) both berberine (10 ,M) and palmatine (10 ,M) caused mild DNA damage as determined by the alkaline comet assay which measures single strand breaks. Berberine and palmatine are the only Goldenseal alkaloids with appreciable absorption above 400 nm. Because light at wavelengths below 400 nm is cut off by the anterior portion of the adult human eye only berberine and palmatine were tested for phototoxicity to human retinal pigment epithelial (hRPE) cells. Although berberine did damage hRPE cells when irradiated with visible light (, > 400 nm) approximately 10 times higher concentrations were required to produce the same amount of damage as seen in lens cells. Palmatine was not phototoxic to hRPE cells. Neither berberine nor palmatine photodamaged DNA in hRPE. Infusions of Goldenseal are estimated to contain ,1 mM berberine, while in tinctures the alkaloid concentration may be more than 10 times higher. Our findings show that eyewashes and lotions derived from Goldenseal or containing berberine must be used with caution when the eyes are exposed to bright sunlight but that oral preparations are not likely to cause ocular phototoxicity. [source] Analysis of major alkaloids in Rhizoma coptidis by capillary electrophoresis-electrospray-time of flight mass spectrometry with different background electrolytesELECTROPHORESIS, Issue 10 2008Junhui Chen Abstract CE-based techniques with DAD and detection ESI-TOF-MS have been developed for the analysis of seven protoberberine alkaloids and one aporphinoid alkaloid in Huanglian (Rhizoma coptidis), a well-known traditional Chinese herbal medicine. One aqueous BGE and one nonaqueous BGE were developed for CE-DAD and CE-MS analyses, and the CE-ESI-TOF-MS conditions including nebulizer gas pressure, the sheath-liquid composition, its flow rate, etc. were optimized. Eight main alkaloids in R. coptidis could be separated with baseline resolution by CE-DAD with these two different BGEs, and identified by TOF-MS analysis. Moreover, three major alkaloids (berberine, palmatine, and jatrorrhizine) could be quantified accurately by CE-DAD and CE-MS with the BGE system consisting of 50:50 v/v water and ACN containing 50,mM ammonium acetate at pH,6.8. Both techniques provided similar LODs and could be applied with confidence within similar linear dynamic range. However, reproducibility and speed of analysis were better using CE-DAD. When the CE technique was compared with the RP-HPLC method, the CE-DAD and CE-MS methods provided greater efficiency and faster analysis speed, i.e., achieving baseline resolution for all the eight main basic compounds in less than 14,min. The CE method, as a viable alternative to HPLC, is suitable for use as a routine procedure for the rapid identification and quantification of basic compounds in herbal or natural product applications. [source] Comparative analysis of the chemical profile of wild and cultivated populations of Corydalis saxicola by high-performance liquid chromatographyPHYTOCHEMICAL ANALYSIS, Issue 5 2007Hui-liang Li Abstract Studies on the simultaneous determination and chemical fingerprinting of alkaloids in Corydalis saxicola Bunting. (Yanhuanglian) were performed for authentication purposes. Ninety samples prepared from different parts of C. saxicola, including whole plants, roots, stems, leaves and flowers, from wild and cultivated populations, were submitted to quantitative determination and fingerprint analysis. Five major alkaloids, namely, tetradehydroscoulerine, dehydroapocavidine, dehydroisoapocavidine, coptisine and dehydrocavidine, were quantitatively analysed by reversed-phase HPLC with acceptable recoveries (>98.2%). Chemical fingerprinting of C. saxicola was established and involved 11 markers. The results indicated that there were no obvious differences between the chemical profiles of wild and of cultivated C. saxicola populations, and that the mean alkaloid contents of the five marker compounds in cultivated populations were significantly higher than those of the wild plants. The highest content of total alkaloids (up to 28.8 mg/g) was found in roots of C. saxicola. The total alkaloids of the leaves were approximately 50% of those of roots, suggesting that the leaves may be employed as an alternative source of alkaloids. Chemical fingerprints and quantitative HPLC analysis will have a positive impact on the conservation and cultivation of this medicinal plant. Copyright © 2007 John Wiley & Sons, Ltd. [source] Solid-phase extraction and reversed-phase high-performance liquid chromatography of the five major alkaloids in Narcissus confususPHYTOCHEMICAL ANALYSIS, Issue 6 2002Susana López Abstract A novel, fast and precise method, combining solid-phase extraction and reversed-phase high-performance liquid chromatography is described for the quantitative determination of five alkaloids (galanthamine, N -formylnorgalanthamine, haemanthamine, homolycorine and tazettine/pretazettine) from bulbs of wild Narcissus confusus, a high galanthamine-containing plant species growing in the Iberian Peninsula. Copyright © 2002 John Wiley & Sons, Ltd. [source] | ||||||||||||||||