Xiaojian Gong

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.

Anti-inflammatory, antiviral and quantitative study of quercetin-3-O-β-D-glucuronide in Polygonum perfoliatum L.

Quercetin-3-O-β-D-glucuronide, isolated from Polygonum perfoliatum L., was evaluated by antiviral efficacy against influenza A virus and anti-inflammatory activity in vivo in mouse, and it was used for quality evaluation of P. perfoliatum L.. In vivo study, oral administration of quercetin-3-O-β-D-glucuronide significantly suppressed ear edema induced by dimethyl benzene and peritoneal permeability induced by acetic acid in mice, and quercetin-3-O-β-D-glucuronide also showed to possess inhibitory activity against influenza A virus (FLUAV). In the present study, additionally, a rapid, simple and sensitive method for quantitative analysis of quercetin-3-O-β-D-glucuronide in P. perfoliatum L. was developed using high performance liquid chromatography (HPLC) coupled with photodiode array detection. The separation was carried out on a Lichrosher-C18 column (250 mm × 4.6mm, 5 μm) together with a C18 guard column at isocratic elution systems of methanol (A) and 0.05% aqueous phosphoric acid (B) (43:57, v/v) with detection wavelength at 258 nm and column temperature at 30°C. The method was validated for linearity, repeatability, limit of quantification (LOQ), precision and robustness. The contents of quercetin-3-O-β-D-glucuronide in 28 samples from different regions of China were between 0.06% and 2.09%. The developed analytical method was applied to investigate P. perfoliatum L. and for quality control of the herb.

An UHPLC-MS/MS method for simultaneous quantification of gallic acid and protocatechuic acid in rat plasma after oral administration of Polygonum capitatum extract and its application to pharmacokinetics.

ETHNOPHARMACOLOGICAL RELEVANCE Polygonum capitatum Buch.-Ham. ex D. Don has been traditionally used by Hmong for the treatments of urinary tract infections and pyelonephritis. Gallic acid (GA) and protocatechuic acid (PCA) are regarded as two of the main bioactive compounds in the herb. MATERIALS AND METHODS A rapid, selective and sensitive UHPLC-ESI-MS/MS method was established and validated for the quantification of GA and PCA in rat plasma after oral administration of P. capitatum extract. Concentrations of GA and PCA were determined at different time points after dosing 20 mg/kg (equivalent to 4 mg/kg of GA and 0.3 mg/kg of PCA), 60 mg/kg and 120 mg/kg of P. capitatum extract. The main pharmacokinetic parameters of GA and PCA were obtained based on the analysis of the plasma sample by non-compartmental analysis. RESULTS After oral administration of P. capitatum extract, GA and PCA were quickly absorbed and showed a dose-dependent profile. Pharmacokinetic parameters for GA and PCA following oral administration of the extract were respectively: Cmax 246.24-806.27 and 15.73-30.72 ng/mL; Tmax 40-100 and 20-40 min. In the rats treated with P. capitatum t1/2 and Tmax of GA were prolonged by comparing with that of its pure form. CONCLUSION Other compounds in P. capitatum extract may be metabolized to GA, which affected the pharmacokinetic profiles of GA. This pharmacokinetic study seems to be useful for a further clinical study of P. capitatum extract.

Relative bioavailability of gastrodin and parishin from extract and powder of Gastrodiae rhizoma in rat

A rapid, sensitive and reliable UHPLC-ESI-MS/MS method was developed for simultaneous determination of gastrodin and parishin in rat plasma. The LLOQ of the two analytes were 1.00×10(-1) and 8.30×10(-5)μg/mL, respectively. The intra-day and inter-day precision were all less than 10% of the relative standard deviation (RSD), whilst the accuracy were all within ±15% of the relative error (RE). The proposed method was successfully applied for pharmacokinetics study on the two analytes in rats after oral administration of Gastrodiae rhizoma (GR) extract and powder at low, medium and high dosages. Blood samples were collected from the suborbital vein at predetermined time points and were precipitated using methanol. Chromatographic separations were carried out on a Kinetex XB-C18 column (2.1mm×150mm, 1.7μm) with a gradient mobile phase of acetonitrile-water with 0.1% formic acid as a modifier. The pharmacokinetic parameters of the two analytes in rats were obtained and the relative bioavailability of gastrodin and parishin in two formulations were calculated. The results indicated that higher bioavailability was obtained when low dosage of GR powder was used, whereas, higher bioavailability values were obtained when medium and high dosages of GR extract were used.

Optimization of the microwave-assisted extraction and antioxidant activities of anthocyanins from blackberry using a response surface methodology

Blackberry contains high amounts of anthocyanins, whose extraction method is closely related with anthocyanin content and antioxidant activity. The extraction yield and antioxidant capacity acted as the comprehensive evaluation indexes, and a Box–Behnken design (BBD) of response surface methodology (RSM) was employed to further optimize the microwave-assisted extraction (MAE) conditions for blackberry anthocyanins (BBAC). A significant correlation was found between the double indexes extraction yield and the antioxidant capacity (P < 0.01). The results showed that the optimized extraction conditions included a microwave power of 469 W, a solvent concentration of 52%, a liquid–solid ratio of 25 g mL−1, and a microwave time of 4 min. Under these conditions, the mean experimental value of the extraction yield (2.18 ± 0.06 mg g−1), ABTS assay (32.18 ± 1.54 μM TEAC per g) and DPPH assay (27.18 ± 1.33 μM TEAC per g) corresponded well with the predicted values. Moreover, these mean experimental values were 120% higher than those obtained during ethanol leaching extraction.

Determination of dehydroevodiamine in Evodia rutaecarpa (Juss.) Benth by high performance liquid chromatography and classification of the samples by using hierarchical clustering analysis.

A simple, sensitive and accurate liquid chromatographic method with photodiode-array detection was developed for determination of dehydroevodiamine with detection wavelength at 368 nm and column temperature at 30 degrees C. The separation was carried out on an Agilent Zorbax SB-C(18) column (250 mm x 4.6 mm, 5 microm) together with a C(18) guard column. The mobile phase was acetonitrile-water (containing 30 mM sodium acetate trihydrate and 0.15% acetic acid) in the ratio of 30:70 (v/v) delivered at a flow rate of 1 mL/min. Excellent linear behavior was observed over the concentration range investigated, with correlation coefficient (R(2))=0.9998. This validated method was applied to determine the contents of dehydroevodiamine in 36 samples from different regions of China, and hierarchical clustering analysis was firstly used to classify and differentiate Evodia rutaecarpa samples. The analysis is specific and can be successfully applied to analyze E. rutaecarpa which is helpful for quality control of the herb.

Optimization of quercitrin and total flavonoids extraction from Herba Polygoni Capitati by response surface methodology

Objective: To optimize the conditions for extraction of quercitrin and total flavonoids (TF) from Herba Polygoni Capitati (Touhualiao in Chinese) by using response surface methodology (RSM). Materials and Methods: A central composite design (CCD) was adopted to investigate the effects of three independent variables including solvent composition (%), solvent-material ratio (ml/g) and extraction time (min) on the responses, quercitrin and TF yields. Results: The optimized conditions of the extraction are as follows: Ethanol concentration, 65.63%; solvent-material ratio, 10.55:1 (ml/g); extraction time, 54.33 min. The established mathematical model described the factors of experimental parameters well and provided a statistically accurate prediction of the optimum yields of quercitrin and TF. Conclusion: The experimental values agreed with those predicted by the established mathematical model, thus indicating the suitability of the model employed and the success of RSM in optimizing the extraction conditions.

Studies on Chromatographic Fingerprint and Fingerprinting Profile-Efficacy Relationship of Saxifraga stolonifera Meerb.

This work investigated the spectrum-effect relationships between high performance liquid chromatography (HPLC) fingerprints and the anti-benign prostatic hyperplasia activities of aqueous extracts from Saxifraga stolonifera. The fingerprints of S. stolonifera from various sources were established by HPLC and evaluated by similarity analysis (SA), hierarchical clustering analysis (HCA) and principal component analysis (PCA). Nine samples were obtained from these 24 batches of different origins, according to the results of SA, HCA and the common chromatographic peaks area. A testosterone-induced mouse model of benign prostatic hyperplasia (BPH) was used to establish the anti-benign prostatic hyperplasia activities of these nine S. stolonifera samples. The model was evaluated by analyzing prostatic index (PI), serum acid phosphatase (ACP) activity, concentrations of serum dihydrotestosterone (DHT), prostatic acid phosphatase (PACP) and type II 5α-reductase (SRD5A2). The spectrum-effect relationships between HPLC fingerprints and anti-benign prostatic hyperplasia activities were investigated using Grey Correlation Analysis (GRA) and partial least squares regression (PLSR). The results showed that a close correlation existed between the fingerprints and anti-benign prostatic hyperplasia activities, and peak 14 (chlorogenic acid), peak 17 (quercetin 5-O-β-d-glucopyranoside) and peak 18 (quercetin 3-O-β-l-rhamno-pyranoside) in the HPLC fingerprints might be the main active components against anti-benign prostatic hyperplasia. This work provides a general model for the study of spectrum-effect relationships of S. stolonifera by combing HPLC fingerprints with a testosterone-induced mouse model of BPH, which can be employed to discover the principle components of anti-benign prostatic hyperplasia bioactivity.

Characterizations and hepatoprotective effect of polysaccharides from Mori Fructus in rats with alcoholic-induced liver injury

Crude polysaccharides of Mori Fructus (MFPs) were found to have anti-inflammatory antioxidant, and immuno-enhancing activities. However, the structure of the polysaccharides was ambiguous and its holistic hepatic protection evaluation was defective. This study was conducted to illustrate the characterization of MFPs, and evaluate its hepatoprotective activities. The results found that MFPs contained 67.93±1.18% carbohydrates, 31.03±0.54% uronic acid, and little protein and sulfate. The average molecular weight was ranging from 112.2kDa to 181.9kDa. Monosaccharide component analysis indicated that MFPs was mainly composed of glucose, galacturonic acid, rhamnose and galactose. Both the acute and subacute alcoholic-induced liver injury animal models were adopted to evaluate the MFPss hepatoprotective activity. After administration of MFPs, both serological indexes (aspartate aminotransferase and alanine aminotransferase) and hepatic indicators (glutathione, superoxide dismutase, glutathione peroxidase and malondialdehyde) were improved by comparing with the non-MFPs group. The hepatic histopathology results also showed a prominent lipid degeneration and microvesicular steatosis attenuation in the MFPs groups. These outstanding hepatic protecting activities of MFPs might be related to its activation of ethanol dehydrogenase, elimination of free radicals and/or inhibition of lipid peroxidation capacities. MFPs could be important active substances for preventing and remedying liver injury.

A polyamide resin based method for adsorption of anthocyanins from blackberries

The present study deals with the downstream processing of anthocyanins from blackberries in order to obtain anthocyanins in a purified form. Adsorption was carried out employing four different mesh sizes of polyamide resin and among these, the 60–100 mesh polyamide resin showed the highest adsorption capacity (4.41 mg mL−1 of the adsorbent) and desorption capacity (3.29 mg mL−1 of the adsorbent). Adsorption results were found to correlate best using the Freundlich equation at all the temperatures studied. The second order kinetics model was found to be more appropriate to describe the adsorption of anthocyanins. Under all conditions, the polyamide resin showed optimal adsorption and desorption capacity towards anthocyanins at an initial concentration of 0.75 mg mL−1, an adsorption liquid pH of 1, an eluent pH of 3 and an ethanol concentration of 80%. The dynamic adsorption process parameters for the purification of anthocyanins using the 60–100 mesh polyamide resin were as follows: processing volume, 5 BV; the flow rate of adsorption, 5 BV per h; the temperature of adsorption, 15 °C; eluent volume, 3.5 BV and the flow rate of desorption, 5 BV per h. Polyamide resin adsorption resulted in a gram of concentrated blackberry extract that contained 432 mg of anthocyanins, which was superior to cation exchange resin adsorption (160 mg g−1) and macroporous adsorbent resin adsorption (176 mg g−1). This method provides an efficient and low-cost approach for anthocyanin purification for industrial applications.