Yanhong Shi

Quantitative and Chemical Fingerprint Analysis for the Quality Evaluation of Isatis indigotica based on Ultra-Performance Liquid Chromatography with Photodiode Array Detector Combined with Chemometric Methods

A simple and reliable method of ultra-performance liquid chromatography with photodiode array detector (UPLC-PDA) was developed to control the quality of Radix Isatidis (dried root of Isatis indigotica) for chemical fingerprint analysis and quantitative analysis of eight bioactive constituents, including R,S-goitrin, progoitrin, epiprogoitrin, gluconapin, adenosine, uridine, guanosine, and hypoxanthine. In quantitative analysis, the eight components showed good regression (R > 0.9997) within test ranges, and the recovery method ranged from 99.5% to 103.0%. The UPLC fingerprints of the Radix Isatidis samples were compared by performing chemometric procedures, including similarity analysis, hierarchical clustering analysis, and principal component analysis. The chemometric procedures classified Radix Isatidis and its finished products such that all samples could be successfully grouped according to crude herbs, prepared slices, and adulterant Baphicacanthis cusiae Rhizoma et Radix. The combination of quantitative and chromatographic fingerprint analysis can be used for the quality assessment of Radix Isatidis and its finished products.

Radix Paeoniae Rubra and Radix Paeoniae Alba Attenuate CCl4-Induced Acute Liver Injury: An Ultra-Performance Liquid Chromatography-Mass Spectrometry (UPLC-MS) Based Metabolomic Approach for the Pharmacodynamic Study of Traditional Chinese Medicines (TCMs)

Metabolomics has been frequently used in pharmacodynamic studies, especially those on traditional Chinese medicine (TCM). Radix Paeoniae Alba and Radix Paeoniae Rubra are popularly used in TCM, and both have hepatoprotective effects. In this study, a CCl4-induced acute liver injury rat model was established and confirmed by the observed serum aminotransferase activities. The metabolomics approach was applied to study the influence of Radix Paeoniae Alba and Radix Paeoniae Rubra on the metabolic changes in rats with acute liver injury. The partial least-squares-discriminant analysis (PLS-DA) of rat serum and their ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) fingerprints allowed discrimination of controlled, acute liver injury-model rats after administration of the two types of TCMs. The time-dependent PLS-DA plots showed that the changes in the metabolic patterns of the rats, which were administered with the TCMs, had stabilized within 2 h after they received the intraperitoneal CCl4 injection. The results indicated the protective effect of TCMs against liver injury. Several potential biomarkers were detected and identified, which included creatine, deoxycholic acid, choline, 5-methylenetetrahydrofolate, folic acid, and glycocholic acid. The physiological significance of these metabolic changes was discussed.

Biotransformation of glucosinolates epiprogoitrin and progoitrin to (R)- and (S)-Goitrin in Radix isatidis.

Radix isatidis is an important traditional Chinese medicine with antiviral efficacy. (R)- and (S)-Goitrin are its main bioactive constituents in the 2010 edition of the Chinese Pharmacopoeia. (R)- and (S)-Goitrin are the breakdown products of epiprogoitrin and progoitrin from R. isatidis. The biotransformation of glucosinolates epiprogoitrin and progoitrin to (R)- and (S)-goitrin, however, is still unclear. In the current paper, the biotransformation of glucosinolates was studied. First, the high-performance liquid chromatography methods to analyze glucosinolates and their breakdown products were developed. Then, the biotransformation of individual glucosinolates such as epiprogoitrin and progoitrin was investigated under different pH conditions. Lastly, their biotransformation under five extraction environments was studied. The results showed that (R)- and (S)-goitrin were the most noteworthy breakdown products. Their relative transformation rates were about 70-80%, and the influence of different extraction environments on the transformation rate was not significant. These results would serve as a theoretical basis for industrial production and quality control and would be helpful for further studies on the biotransformation of glucosinolates.

CHROMATOGRAPHIC FINGERPRINT STUDY ON WATER-SOLUBLE EXTRACTS OF RADIX ISATIDIS, FOLIUM ISATIDIS, AND THEIR PREPARATIONS BY HPLC-DAD TECHNIQUE

Reliable, reproducible, and valid fingerprint analysis methods using high-performance liquid chromatography-photodiode array detection (HPLC-DAD) for characteristic bioactive water-solution extracts of Radix Isatidis, Folium Isatidis, and their preparations were firstly developed and validated. Ninety-three batches of samples were investigated and the common fingerprinting profile of water-soluble extracts was established with professional analytical software recommended by the State Food and Drug Administration (SFDA). The reference chromatogram was also generated with 24 common peaks showing large peak areas and good separation from adjacent peaks, the total peak areas of 24 common peaks were more than 85% of the total peak areas. Nine chemical components—including cytidine, progoitrin, hypoxanthine, epiprogoitrin, uridine, adenosine, xanthine, gluconapin, and R,S-goitrin—were identified as characteristic peaks. Hierarchical clustering analysis (HCA) and Principal Component Analysis (PCA) were also performed to classify and differentiate the 93 batches of the samples. As a result, data obtained from the two analytical methods showed good consistence with each other in an overall trend. The chromatographic fingerprint methods by HPLC-DAD were very useful in evaluating and controlling the quality of Radix Isatidis, Folium Isatidis, and their preparations.

Separation and Quantification of Four Main Chiral Glucosinolates in Radix Isatidis and Its Granules Using High-Performance Liquid Chromatography/Diode Array Detector Coupled with Circular Dichroism Detection

As chemical drugs, separation and quantification of the specific enantiomer from the chiral compounds in herbal medicines are becoming more important. To clarify the chemical characterization of chiral glucosinolates—the antiviral active ingredients of Radix Isatidis, an optimized efficient method of HPLC-UV-CD was developed to simultaneously separate and quantify the four main chiral glucosinolates: progoitrin, epiprogoitrin, and R,S-goitrin. The first step was to determine progoitrin, epiprogoitrin, and R,S-goitrin using HPLC-UV, and then determine the R-goitrin and S-goitrin by coupling with CD detection. Subsequently, through the linear relations between anisotropy factor (g factor) and the percent optical purity of R-goitrin, the contents of R-goitrin and S-goitrin from the R,S-goitrin mixture were calculated separately. Furthermore, the chemical composition features of the four chiral glucosinolates in 37 samples from crude drugs, decoction pieces, and granules of R. Isatidis were conducted. The total content of the four glucosinolates was obviously higher in crude drugs, and the variance character of each glucosinolate contents was different. In summary, the accurate measurement method reported here allows for better control of the internal quality of R. Isatidis and its granules and provides a powerful approach for the analysis of other chiral components in traditional Chinese medicines.

Abietane Diterpenoids from the Roots of Clerodendrum trichotomum and Their Nitric Oxide Inhibitory Activities

Twelve new abietane diterpenoids (1-12) and 31 known analogues (13-43) were isolated from a medicinal Chinese herb, Clerodendrum trichotomum Thunberg. The absolute configurations of 1-3 were established on the basis of ECD and X-ray crystallography data, whereas that of 4 was elucidated by comparison of experimental and calculated ECD data. Eight diterpenoids, 15,16-dehydroteuvincenone G (1), trichotomin A (4), 2α-hydrocaryopincaolide F (7), villosin C (20), 15-dehydro-17-hydroxycyrtophyllone A (22), demethylcryptojaponol (38), 6β-hydroxydemethylcryptojaponol (39), and trichotomone (43), exerted inhibitory effects against NO production with IC50 values of 5.6-16.1 μM. The structure-activity relationships of the isolated diterpenoids are also estimated.

Three new C-glycosyflavones with acetyl substitutions from Swertia mileensis

Three new acetylated C-glycosylflavones, 3″,6″-di-O-acetylswertiajaponin (1), 4″,6″-di-O-acetylswertiajaponin (2), and 6″-O-acetylswertiajaponin (3), together with six known compounds were isolated from the whole herb of Swertia mileensis. Their structures were elucidated on extensive NMR experiments and mass spectrometry studies. 1H and 13C NMR data exhibited doublet signals at room temperature. Variable temperature 1H NMR experiments were carried out to investigate the presence of rotational isomerism of C-glycosylflavones. All compounds showed potential antioxidant activities against apoptosis of H2O2-induced human embryo liver L02 cells.