[A simultaneous determination of evodiamine and rutaecarpine in oriental pharmaceutical decoctions containing Evodia fruit by ion-pair high-performance liquid chromatography]

Development and validation of an UPLC-ESI-MS/MS method for determination of dehydroevodiamine, limonin, evodiamine, and rutaecarpine in Evodiae Fructus

Objective:

Evodiae Fructus (EF), one of the most widely used traditional Chinese medicines, mainly consists of alkaloids, is widely used for the treatments of headache and gastrointestinal disorders. In this study, a sensitive and reliable UPLC-ESI-MS/MS method was developed for qualitative determination of dehydroevodiamine, limonin, evodiamine, and rutaecarpine.

Materials and Methods:

Chromatographic separations were accomplished on a Phenomenex Kinetex XB-C18 column (2.1 × 150 mm, 1.7 μm) by using a gradient elution profile with a mobile phase consisting of 0.5% formic acid in water (A) and acetonitrile (B). Detection was performed using multiple reactions monitoring mode under ESI in the positive ion mode.

Results:

The results showed good linearity over the investigated concentration ranges (R²>0.9900) for the analytes. The limit of quantitations (LOQs) were 6.88 ng/mL for dehydroevodiamine, 18.6 ng/mL for limonin, 6.24 ng/mL for evodiamine, and 2.56 ng/mL for rutaecarpine, respectively. Intraday and interday precisions (relative standard deviations, %) were <5% and accuracies ranged from 92% to 106%.

Conclusion:

The validated method was successfully applied to assay the contents of the four compounds in EF samples from different regions, with which just 10 min was needed to analyze each sample.

Separation and Determination of Active Components in Evodiae fructus and its Pharmaceutical Preparations by Non-Aqueous Micellar Electrokinetic Chromatography

In this paper, an easy, economical and effective nonaqueous micellar electrokinetic capillary chromatography (NAMECC) method for the simultaneous determination of two bioactive components (evodiamine and rutaecarpine) in Evodiae Fructus and its pharmaceutical preparations was developed for the first time. After optimization of the separation conditions and concentration conditions, the two alkaloids can be separated by using a fused-silica capillary column (57 × 75 μm I.D.) with a running buffer of 140 mM sodium cholate (SC) in methanol and detected with a diode-array detector (228nm). The second-order derivative electropherograms were applied for resolving overlapping peaks in complicated preparations. Regression equations revealed good linear relationships (correlation coefficients 0.9969-0.9999) between peak heights in second-order derivative electropherograms and concentrations of the two analytes. The relative standard deviations (RSD) of the migration times and the peak height of the two constituents were less than 0.49% and 1.6%. The recoveries of two constituents ranged from 93.5 to 105.6%. The results indicated that baseline separation of the analytes was hard to be achieved in real samples sometimes and second-order derivative electropherograms was applicable for the resolving and analysis of overlapping peaks.

Simultaneous determination of evodiamine and evodine in Beagle dog plasma using liquid chromatography tandem mass spectrometry

A sensitive, rapid, and specific liquid chromatography/tandem mass spectrometry assay has been established and validated for the quantitation of evodiamine and evodine in Beagle dog plasma. Plasma samples of 0.2 ml were processed by liquid-liquid extraction with n-hexane/ethyl acetate (2:1, v/v). Chromatographic separations were done on a Symmetry C18 column (100 mm × 4.6 mm, ID, 5 μm) at 35°C with a linear gradient of methanol and 20 mM ammonium formate containing 0.2% formic acid. Evodiamine, evodine, and glibenclamide [internal standard (IS)] were ionized with an electrospray ionization source operated in positive ion mode. The MS/MS transitions were m/z 304.1 → 161.1 for evodiamine, m/z 471.2 → 425.1 for evodine, and m/z 494.1 → 369.1 for IS. Calibration curves were linear over the concentration range of 0.1-100 ng/ml for evodiamine and 0.5-500 ng/ml for evodine. The mean extraction recoveries were 88.10 ± 3.21% for evodiamine and 81.24 ± 4.07% for evodine. The intra- and inter-day precisions were less than 11.10% and 12.81%, and the accuracy was within ± 11.76% for both analytes. Evodiamine and evodine were stable during storage and analytical periods. The validated method has been successfully applied to a pharmacokinetic study of evodiamine and evodine in beagle dogs after oral administration.

Chromatographic fingerprint study on Evodia rutaecarpa (Juss.) Benth by HPLC/DAD/ESI-MS(n) technique

The LC-ESI-MS(n) method was developed for the analysis and characterization of alkaloids in the extract of E. rutaecarpa (called Wuzhuyu in Chinese). Thirty-six batches of Wuzhuyu from different locations of China were investigated and the common fingerprinting profile was established with a professional analytical software recommended by the State Food and Drug Administration. Fifteen chemical components of the common peaks were identified by multi-stage MS. The effects on the chromatographic profile resulting from different collecting locations, harvesting times or storage times were studied. Hierarchical clustering analysis and principal components analysis were also performed to classify and differentiate the 36 batches of the samples. As a result, those which had same chemical properties were sorted into one cluster, which was very useful in evaluating and controlling the quality of Wuzhuyu.

Quality evaluation of Evodia rutaecarpa (Juss.) Benth by high performance liquid chromatography with photodiode-array detection

A simple, sensitive and accurate HPLC-DAD method was developed for simultaneous determination of wuchuyuamide-I, quercetin, limonin, evodiamine and rutaecarpine in Evodia rutaecarpa that has been widely used as one of the traditional Chinese medicines (TCMs). Chromatographic separations were performed on a reverse-phase C(18) column with the gradient elution of acetonitrile-water and the simultaneous detection at five wavelengths. Good linear behaviors over the investigated concentration ranges were observed with the values of r higher than 0.999 for all the analytes. The recoveries measured at three levels varied from 98.77 to 102.36%. The validated method was successfully applied for the simultaneous determination of the five chemical constituents in 36 batches of samples collected from different regions or time that were investigated and authenticated as E. rutaecarpa (Juss.) Benth. Hierarchical clustering analysis (HCA) and principal components analysis (PCA) were performed to differentiate and classify the samples based on the contents of the five characteristic constituents. The total contents of evodiamine and rutaecarpine in different samples were calculated and the blending method proposed was demonstrated to be very useful in saving resources and in guiding rational herb use.

Determination of evodiamine and rutecarpine in human serum by liquid chromatography–tandem mass spectrometry

Evodiamine and rutecarpine are two kinds of indole alkaloids contained in the fruit of Evodiae fructus, which have been shown to exhibit various bioactivities in humans. A liquid chromatography-tandem mass spectrometric method (LC-MS/MS) was developed for the determination of evodiamine and rutecarpine in human serum. The serum was extracted by solid-phase extraction (SPE) and analyzed using a C18 column and a mobile phase consisting of methanol-water (85:15) solution containing 5 mmol/L ammonium formate at a flow rate of 0.5 mL/min. The mass spectrometer was operated in positive mode, employing the extracted ion chromatogram (EIC) for detection and quantitation of evodiamine (m/z 288) and rutecarpine (m/z 304). Good linear relationships between the peak area and the concentration were obtained in the ranges of 5.2-1040 ng/mL and 10.2-1020 ng/mL, with correlation coefficients (r) of 0.999 and 0.998, for evodiamine and rutecarpine, respectively. The repeatabilities (RSD, n=6) of quantitation for evodiamine and rutecarpine were 2.18-4.00% and 2.99-5.67%, respectively, and the recovery ranged from 90.5% to 98.1%. A comparative study of the different ionization and quantitation modes, including ESI-MS, ESI-MS/MS, APCI-MS and APCI-MS/MS, was also accomplished. The MS/MS fragmentation mechanism of the base peak ([M+H](+), m/z 304) of evodiamine was investigated in order to identify the analytes in more complicated body fluid samples.

Elimination of rutaecarpine and its metabolites in rat feces and urine measured by liquid chromatography

Rutaecarpine is an alkaloid isolated from the medicinal herb Evodia rutaecarpa. This study was to evaluate the elimination pathway of rutaecarpine in rat feces and urine. Rutaecarpine and its metabolites (3-, 10-, 11- and 12-hydroxyrutaecarpine) in urine were measured after incubation with beta-glucuronidase. After the rutaecarpine was administered (25 and 100 mg/kg) orally to rats, the urine and fecal samples were collected using a metabolic cage for five consecutive days. For determining rutaecarpine, the mobile phase consisted of acetontrile-10 mM NaH(2)PO(4) (60:40, v/v, pH 4.2 adjusted with orthophosphoric acid) with a flow rate of 1 mL/min. The calibration curve was linear in concentrations of 0.05-50 microg/mL in fecal and urine sample. The results indicated that more than 42% of the rutaecarpine was excreted by feces after oral administration (25 and 100 mg/kg), but only a small amount of rutaecarpine was detected in urine at a higher dose of rutaecarpine (100 mg/kg). After incubation with beta-glucuronidase, the hydroxyrutaecarpine in urine was eluted using methanol-acetonitrile-0.04% formic acid (6:30:64, v/v) with a flow rate of 1.2 mL/min. We conclude that the metabolic pathway of rutaecarpine went through phase I hydroxylation and phase II conjugation, and the major metabolite is 10-hydroxyrutaecarpine eliminated from urine of the rat.

Mechanism-Based Inactivation of Human Liver Microsomal CYP3A4 by Rutaecarpine and Limonin from Evodia Fruit Extract

Evodia fruit (Evodiae Fructus) is used as a herbal medicine prepared from the matured fruit of the Evodia rutaecarpa Bentham or Evodia officinalis Dode, of the Rutaceae plant family. An extract of Evodia fruit in the presence of NADPH was shown to inhibit human liver microsomal erythromycin N-demethylation activity, mediated by cytochrome P450 3A4 (CYP3A4), in a preincubation-time dependent manner. The present study was conducted to identify components of Evodia fruit extract having preincubation-time dependent inhibitory effects on CYP3A4 by analyzing human liver microsomal erythromycin N-demethylation activity. Rutaecarpine, a major component of Evodia fruit, and limonin caused the most dramatic decrease in residual CYP3A4 activity (IC50 before and after 20 min preincubation with: rutaecarpine, >100 microM and 1.4 microM; limonin, 23.5 microM and 1.8 microM, respectively). Furthermore, rutaecarpine and limonin were identified as mechanism-based inhibitors of CYP3A4 from the following observations: 1) The inhibitory effects of rutaecarpine and limonin on CYP3A4 activity were dependent on the preincubation time, 2) The inhibition required NADPH, 3) The inhibition was depressed in the presence of the competitive CYP3A4 inhibitor, ketoconazole, 4) Dialysis resulted in no recovery of CYP3A4 activity. The kinetic parameters for inactivation k(inact) and K(I) were: 0.387 min-1 and 107.7 microM for rutaecarpine, 0.266 min-1 and 23.2 microM for limonin, respectively. These results indicate that rutaecarpine and limonin are mechanism-based inhibitors of CYP3A4.

Simultaneous determination of ephedrine, pseudoephedrine, norephedrine and methylephedrine in Kampo medicines by high-performance liquid chromatography

A simultaneous high-performance liquid chromatographic method for the determination of ephedrine, pseudoephedrine, norephedrine and methylephedrine (ephedrine alkaloids) in Kampo medicines which contain Ephedrae Herba was established. The analysis can be accomplished within 25 min with a Wakosil-II 5C18 HG column by isocratic elution using a mixture of water, acetonitrile and sodium dodecyl sulfate (65:35:0.4) as the mobile phase at a flow-rate of 1.0 ml min(-1), and detection at 210 nm. The detection limits of ephedrine alkaloids are 0.37-1.06 microM per injection (5 microl). This method was applied to analyze the quantities in eight Kampo decoctions; Mao-to, Makyo-yokukan-to, Makyo-kanseki-to, Yokuinin-to, Sho-seiryu-to, Keima-kakuhan-to, Kakkon-to and Kakkon-to-ka-senkyu-sin'i. The concentration (per Ephedrae Herba gram) of ephedrine alkaloids was higher in the Makyo-kanseki-to decoction than in the others. Calcium sulfate from Gypsum Fibrosum raised ephedrine alkaloids dissolution in the Makyo-kanseki-to decoction.