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11.
在硅胶板上用乙酸乙酯—甲醇—浓氨水(17:4:1),分离细叶小檗、粉叶小檗、金花小檗、拟豪猪刺中的药根碱、巴马亭和小檗碱,然后用岛津CS—910型双波长薄层扫描仪,在λ_s=350nm,λ_R=375nm下,用反射法作锯齿扫描,测定了上述四种药用植物中药根碱、巴马亭和小檗碱的含量。 相似文献
12.
Nanostructured electrochemical DNA biosensors for detection of the effect of berberine on DNA from cancer cells 总被引:2,自引:0,他引:2
Ovádeková R Jantová S Letasiová S Stepánek I Labuda J 《Analytical and bioanalytical chemistry》2006,386(7-8):2055-2062
Multi walled carbon nanotubes (MWNT) in dimethylformamide (DMF) or aqueous sodium dodecyl sulfate (SDS) solution, colloidal
gold nanoparticles (GNP) in phosphate buffer solution (PBS), and a GNP–MWNT mixture in aqueous SDS solution have been investigated
for chemical modification of a screen-printed carbon electrode used as the signal transducer of a dsDNA-based biosensor. Differential
pulse voltammetry of the DNA redox marker and the guanine moiety anodic oxidation and cyclic voltammetry with K3[Fe(CN)6] as indicator revealed substantial enhancement of the response of the biosensor, particularly when MWNT in SDS solution was
used. The biosensor was used in testing of berberine, an isoquinoline plant alkaloid with significant antimicrobial and anticancer
activity. Berberine had a very strong, concentration-dependent, effect on the structural stability of DNA from the human cancer
cells (U937 cells) whereas non-cancer cells were changed only when berberine concentrations were relatively high 75 and 50 μg
mL−1.
Figure Schematic illustration of preparation of the nanostructured films: (a) layer-to-layer coverage (DNA/nanomaterial/SPE); (b) mixed coverage (DNA-nanomaterial/SPE) 相似文献
13.
Miyoko Kamigauchi Kazuko Kawanishi Makiko Sugiura Hirofumi Ohishi Toshimasa Ishida 《Helvetica chimica acta》2008,91(9):1614-1624
To prevent the precipitation reaction between glycyrrhizin ( 1 ) and berberine ( 3 ) in the decoctions of Glycyrrhiza/Coptis rhizome or Glycyrrhiza/Phellodendron bark, the presence of cyclodextrin (CD) in the mixture was proven to be effective. The preventing effect decreased in the order γ‐CD>β‐CD, and no effect was observed for α‐CD. On the other hand, the extraction degree of 1 from the natural medicine Glycyrrhia was considerably increased in the presence of γ‐CD, γ‐CD being much more effective than α‐ or β‐CD. Thus, the blocking effect of CD on the precipitate formation between 1 and 3 is suggested to be primarily dependent on the stability of the inclusion complex of the CD with 1 . To establish the structure of such a preferred inclusion complex, the interactions of 1 with β‐ and γ‐CDs were investigated by 1H‐NMR spectroscopy and molecular‐dynamics (MD) calculations. The 1H‐NMR measurements showed that the increase in solubility of 1 in H2O is dependent on the degree of its inclusion into the CD, which depends on the molecular size of the CD. The MD calculations suggested that the H‐bond interactions are sufficiently strong to form a stable [ 1 /γ‐CD] complex, in which the lipophilic rings C, D, and E of 1 are fully inserted into the molecular cavity of γ‐CD, thus forming a kind of structure covered by a hydrophilic molecular capsule, while such an interaction mode is impossible for α‐ or β‐CD. 相似文献
14.
The supramolecular interaction of β-cyclodextrin dimer with berberine hydrochloride was studied in aqueous KH2PO4-H3PO4 buffer solution of pH 2.00 at room temperature by spectrofluorimetry. The apparent association constant of the complex was 1.53 × 104 L mol−1. Based on the significant enhancement of fluorescence intensity of supramolecular sandwich complexes, a spectrofluorimetric method with high sensitivity and selectivity was developed for the determination of berberine hydrochloride in aqueous solution in presence of ethylenediamine linked β-CD dimer. The linear range of the method was 12.8-1.00 × 104 ng mL−1 with the detection limit 3.6 ng mL−1. There was no interference from the normally used in tablets and serum constituents. The proposed method was successfully applied to the determination of berberine hydrochloride in tablets and serum. And then it has a promising potential in therapeutic drug monitoring, pharmokinetis and clinical application. 相似文献
15.
This paper developed a rapid method using near infrared spectroscopy (NIRS) to differentiate two species of Cortex Phellodendri (CP), Cortex Phellodendri Chinensis (PCS) and Cortex Phellodendri Amurensis (PAR), and to predict quantitatively the content of berberine and total alkaloid content in all Cortex Phellodendri samples. Three alkaloids, berberine, jatrorrhizine and palmatine were analyzed simultaneously with a Thermo ODS Hypersil column by gradient elution with a new mobile phase under high-performance liquid chromatography-diode array detection (HPLC-DAD). Berberine content determined by HPLC-DAD was exploited as a critical parameter for successful discrimination between them. Multiplicative scatter correction (MSC), second derivative and Savitsky-Golay (S.G.) were utilized together to correct the scattering effect and eliminate the baseline shift in all near infrared diffuse reflectance spectra as well as to enhance spectral features in order to give a better correlation with the results obtained by HPLC-DAD. With the use of principal component analysis (PCA), samples datasets were separated successfully into two different clusters corresponding to two species. Furthermore, a partial least squares (PLS) regression method was built on the correlation model. The results showed that the correlation coefficients of the prediction models were R = 0.996 for the berberine and R = 0.994 for total alkaloid content. The influences of water absorption bands present in the NIR spectra on the models were also investigated in order to explore the practicability of NIRS in routine use. The outcome showed that NIRS possibly acts as routine screening in the quality control of Chinese herbal medicine. 相似文献
16.
17.
18.
A sensitive and precise high performance liquid chromatography (HPLC)-electrochemical detection (ECD) method has been developed for the simultaneous determination of four isoquinoline alkaloids including berberine, jatrorrhizine, coptisine and palmatine in Chinese medicine Coptis chinensis. The typical HPLC analysis was performed on WondaSil® C18-WR column (250 × 4.6 mm, 5 μm) with the mobile phase comprising 40 mM phosphate buffer (pH 7.0)–acetonitrile (40:60, v/v) at the flow rate of 0.8 mL min−1. The electrochemical detection employed a three electrode system with a bare glassy carbon electrode at +1.3 V versus the Ag/AgCl reference electrode. The limits of detection (LODs) of four alkaloids ranged from 0.01 to 0.03 μmol L−1 and the LOD of berberine was 80 times lower than LOD obtained by UV detection. The rat plasma samples were assayed after oral administration of the traditional Chinese medicine Coptis chinensis by the proposed HPLC-ECD method. The recoveries of this method were ranging from 88.0 to 116%, with the relative standard deviation lower than 3.1% for intra-day precision and 5.7% for inter-day precision. These results show that HPLC-ECD is a useful tool for the quality control of herbal medicine Coptis chinensis and also for pharmacokinetic studies. 相似文献
19.
Maurice O. Iwunze 《Monatshefte für Chemie / Chemical Monthly》2000,131(5):429-435
Summary. Berberine hydrochloride is an alkaloid with little or no fluorescence in water. In sodium dodecylsulfate solutions, the fluorescence
intensity of this compound is enhanced several folds by ion-pairing with the anion of the surfactant. The enhanced fluorescence
intensity reaches a maximum at a surfactant concentration of 4·10−3 M and then decreases to a constant value at the critical micelle concentration and beyond. At concentrations near the maximum,
a calibration sensitivity of 3.23·106/M was obtained. In addition, a good linear dynamic range and a low limit of detection (4·10−5 and 1.5·10−7 M, respectively) were determined. This observation indicates that this surfactant medium could be effectively used in fluorometric
trace analysis of berberine hydrochloride. It was also observed in this work that solvents of low dielectric constant tend
to stabilize this compound and thereby enhance its fluorescence.
Received November 26, 1999. Accepted (revised) January 13, 2000 相似文献
20.
Berberine is one of the most important bioactive compounds used in Chinese herbal drugs to evaluate the quality of the Phellodendron cortex. The cortices of Phellodendron wilsonii and Phellodendron amurense, extracted by using a microwave‐assisted process under a domestic microwave oven in methanol solvent and analyzed by capillary electrophoresis with the buffer solution of 82% 0.1 M aqueous sodium acetate and 18% MeOH (v/v), were demonstrated to be higher in extracting berberine contents and shorter in the process time than those extracted by using a reflux extraction in methanol solvent (for sample B, 2.27 ± 0.08% in 3 min vs. 1.92 ± 0.14% in 5 hrs, respectively). Therefore, the microwave‐assisted process for extraction of berberine is more efficient, rapid and convenient than the reflux extraction and can be used for the extraction of bioactive substances from the crude Chinese drugs. 相似文献