OBJECTIVETo develop a HPLC-DAD method for simultaneous determination of six flavonoids in Scutellaria baicalensis, and study the effect of geographic sources, culturation, harvesting time and processing on the contents of flavonoids.

METHODThe analysis was performed on a Thermo ODS-2 Hypersil column (4.6 mm x 250 mm, 5 microm) at 26 degrees C with a gradient program of acetonitrile-0.1% H3 PO4 aqueous solution-tetrahydrofuran as the mobile phase and a Diode Array Detector as the detector with the detection wavelength at 274 nm. The flow rate was 1.0 mL x min(-1), and the injection value was 20 microL.

RESULTSix flavonoids, baicalin (1), oroxylin A-7-O-glucuronide (2), wogonoside (3), baicalein (4), wogonin (5) and oroxylin A (6), were linear over the selected range with R2 > or = 0.999 3. The average recoveries were between 96.6% -103.0%, and RSD were less then 5.0% (n = 9) for flavonoids 1-6. By analyzing the data obtained, the effect of geographic sources, culturation, harvesting time and processing on the contents of flavonoids were discussed.

CONCLUSIONThis method is simple, sensitive, reliable and reproducible. It can be used for the quality control of S. baicalensis.

Chromatography, High Pressure Liquid ; instrumentation ; methods ; Drugs, Chinese Herbal ; chemistry ; Flavonoids ; chemistry ; Scutellaria baicalensis ; chemistry

As an important herbaceous plant, Scutellaria baicalensis Georgi (Chinese skullcap) is geographically widespread and commonly used throughout the world. In the Chinese medicine market, S. baicalensis has been divided into two primary types, "Ku Qin" (WXR) and "Tiao Qin" (TST). Moreover, TST is also divided into different grades according to the diameter of roots. To explore the distribution patterns of the contents of five biologically activate ingredients (FBAI), we used six-year-old cultivated S. baicalensis and analyzed its growth characteristics as well as the quality difference among different types and diameters in roots. Throughout the entire root, we discovered that contents of the FBAI all initially increased and subsequently decreased from the top to the bottom of the roots. The baicalin content of WXR was less than that of TST. On the contrary, the contents of baicalein, wogonin, and oroxylin A in WXR were up to about two times higher than that in TST. We also found that the 0 to 40 cm part of the S. baicalensis root possessed about 87% of the root biomass and about 92% of the contents of the active ingredients.
Drugs, Chinese Herbal ; chemistry ; Flavanones ; analysis ; Flavonoids ; analysis ; Plant Roots ; chemistry ; Scutellaria baicalensis ; chemistry

Dead heart is an important trait of pith-decayed Scutellariae Radix. The purpose of this study was to clarify the scientific connotation of the dead heart using multi-omics. Metabolomics and transcriptomics combined with multivariate statistical analysis such as principal component analysis(PCA) and partial least squares discriminant analysis(PLS-DA) were used to systematically compare the differences in chemical composition and gene expression among phloem, outer xylem and near-dead xylem of pith-decayed Scutella-riae Radix. The results revealed significant differences in the contents of flavonoid glycosides and aglycones among the three parts. Compared with phloem and outer xylem, near-dead xylem had markedly lowered content of flavonoid glycosides(including baicalin, norwogonin-7-O-β-D-glucuronide, oroxylin A-7-O-β-D-glucuronide, and wogonoside) while markedly increased content of aglycones(including 3,5,7,2',6'-pentahydroxy dihydroflavone, baicalin, wogonin, and oroxylin A). The differentially expressed genes were mainly concentrated in KEGG pathways such as phenylpropanoid metabolism, flavonoid biosynthesis, ABC transporter, and plant MAPK signal transduction pathway. This study systematically elucidated the material basis of the dead heart of pith-decayed Scutellariae Radix with multiple growing years. Specifically, the content of flavonoid aglycones was significantly increased in the near-dead xylem, and the gene expression of metabolic pathways such as flavonoid glycoside hydrolysis, interxylary cork development and programmed apoptosis was significantly up-regulated. This study provided a theoretical basis for guiding the high-quality production of pith-decayed Scutellariae Radix.
Drugs, Chinese Herbal/chemistry* ; Scutellaria baicalensis/chemistry* ; Glucuronides ; Multiomics ; Flavonoids/chemistry*

OBJECTIVETo compare the contents of baicalin in the raw medical material and the different prepared medical materials of Scutellaria baicalensis.

METHODThe contents of baicalin were determined by HPLC. Chromatographic conditions included Hypersil C18 column and the mobile phase consisting of a mixture of methanol-0.04% phosphoric acid (46:54). Baicalin was detected at 280 nm. The standard curve was linear in the range of 0.0280-4.6700 micrograms with correlation coefficient 1.0000. The average recovery of baicalin was 101.22% with RSD = 2.54% (n = 5).

RESULTThe contents of baicalin were 6.80% in raw material, 6.00% and 6.73% in the different prepared medical materials of S. baicalensis respectively.

CONCLUSIONThe two different kinds of preparing methods can be used to the raw material of S. baicalensis.

Chromatography, High Pressure Liquid ; Flavonoids ; analysis ; Hot Temperature ; Plants, Medicinal ; chemistry ; Scutellaria baicalensis ; chemistry ; Technology, Pharmaceutical

OBJECTIVETo compare the chemical differences in 4 commercial specifications of Scutellaria Radix, research the affection of decayed central xylem part on the crude drug's chemical composition and provide scientific data for production, processing, sale and clinical applications of Scutellariae Radix.

METHODMacroscopical identification method was used for observation of different specifications of Scutellariae Radix, including Qinwang, Tiaoqin both in 1st class and 2nd class and inferior samples. HPLC fingerprint method was used to analyze chemically the decayed central xylem part and non-decayed part as well as complete sample, and the results were described by the relative peak area.

RESULTThe morphological characteristics of 4 specifications are greatly different from one another mainly in root diameters, root lengths and the proportions of decayed central xylem part in the root, and so the authors classified Qinwang and Tiaoqin in 1st class as Kuqin for all samples of them which have decayed central xylem; and classified Tiaoqin in 2nd class and the inferior samples as Ziqin, for having little decayed central xylem. The 4 specifications collected from the same producing area have similar HPLC fingerprint profile to one another, while they are different in relative peak area. The peak area ratios of aglycone to their glucuronide (baicalein/baicalin, wogonin/wogonoside, oroxylin A/oroxylin A-7-O-glucuronide) from Kuqin were significantly higher than those of Ziqin. The total area of the peaks in HPLC fingerprint chromatographs of decayed central xylem part were quite lower than that of non-decayed part, whereas peak areas of the characteristic peaks and the 3 peak area ratios of decayed central xylem were significantly higher than those of non-decayed part which could be used as characteristic parameters to distinguish Kuqin and Ziqin.

CONCLUSIONFour commercial specifications of Scutellariae Radix can be classified as Kuqin and Ziqin respectively according to morphological characteristics and the proportions of decayed central xylem part in the root. The chemical characteristics of Kuqin and Ziqin are different from each other, so it's worth clarifying the similarities and differences of Kuqin and Ziqin in future. The result in this research can be used as references for identification and quality control of Scutellariae Radix specifications, and investigation on effective components of Kuqin and Ziqin.

Chromatography, High Pressure Liquid ; Drugs, Chinese Herbal ; chemistry ; standards ; Quality Control ; Scutellaria baicalensis ; chemistry

The on-line monitor for the changes in the content of baicalin in Scutellariae Radix formula particles during the extraction process was conducted by using near infrared spectroscopy (NIR). High performance liquid chromatography (HPLC) was used as a reference method. Kennard-Stone (KS) was used to divide sample sets, so as to compare different pretreatment methods. The synergy interval partial least squares (SiPLS) was used to screen out modeling wave band to establish partial least-squares models. The relative error method was applied to predict forecast set samples of Scutellariae Radix in three extraction phases. The results showed that the model established by Savitzky-Golay smoothing with 11 points (SG11 points) was the best, with the root mean square with cross validation (RMSECV), root mean square error of correction (RMSEC) and root mean square error of prediction (RMSEP) of baicalin of 0.092 7, 0.134 4 and 0.114 8, respectively, the determination coefficient R2 of greater than 0.99, and the relative error of baicalin content of less than 5%. This indicates that the on-line near infrared reflectance spectroscopy could be applied in on-line monitor and quality control of the extraction process of Scutellariae Radix formula particles.
Automation ; methods ; Drugs, Chinese Herbal ; chemistry ; standards ; Quality Control ; Scutellaria baicalensis ; chemistry ; Spectroscopy, Near-Infrared ; methods

Flavonoids are the most abundant constituents and induce these the rapeutic effects against inflammation, gastrointestinal infections, cardiovascular diseases, and respiratory. Most of these flavonoids have low content in Scutellarie Radix. It was difficult to detect some minor compounds by using LC-MS method with full scan. Based on the review of flavonoids that had been extracted from Scutellariae Radix, a method with PREC-IDA-EPI technique was developed and applied to Scutellariae Radix by using UPLC-MS/MS. A total of 97 flavonoids were identified, including 29 aglycones and 68 -glycosides. This study laid the foundation for pharmacodynamicss of Scutellariae Radix.It is believed that an individual detection scheme based on the PREC-IDA-EPI technique could be used to identify unknown compounds.
Chromatography, Liquid ; Drugs, Chinese Herbal ; chemistry ; Flavonoids ; isolation & purification ; Scutellaria baicalensis ; chemistry ; Tandem Mass Spectrometry

With reference to the production process documented in Chinese Pharmacopoeia, this paper prepared the calibrator samples of Xiaochaihu Granules from multiple batches and established a method for fingerprint analysis and content determination that could be used to evaluate Xiaochaihu Granules available in market. Multiple batches of Chinese herbal pieces contained in Xiaochaihu Granules were collected for preparing the calibrator samples according to the process in Chinese Pharmacopoeia. Following the establishment of fingerprints for calibrator samples by UHPLC, the method for determining the contents of saikosaponin B2, saikosaponin B1, baicalin, wogonoside, baicalein, liquiritin, glycyrrhizin G2 and glycyrrhizic acid in Xiaochaihu Granules was established. The experimental results showed that the fingerprints of calibrator samples had 26 common peaks, covering the chemical compounds of main herbs Bupleuri Radix, Scutellariae Radix, Changii Radix, Glycyrrhizae Radix et Rhizoma, and Rhizoma Zingiberis Recens. The similarity of fingerprints for 47 batches of Xiaochaihu Granules from 31 companies with the calibrator sample fingerprint ranged from 0.74 to 0.99, indicating good applicability of the established fingerprint. The contents of main components baicalin, saikosaponin B2, and glycyrrhizic acid in Xiaochaihu Granules were within the ranges of 22.917-49.108 mg per bag(RSD 19%), 0.28-2.19 mg per bag(RSD 62%), and 0.897-6.541 mg per bag(RSD 41%), respectively. The quality difference in saikosaponin B2, and glycyrrhizic acid among different manufacturers was significant. The fingerprint analysis and content determination method for calibrator samples of Xiaochaihu Granules prepared according to the production process in Chinese Pharmacopoeia has been proved suitable for evaluating the quality of Xiaochaihu Granules from different manufacturers. Saikosaponin B2, glycyrrhizic acid, and liquiritin should be added as content control indicators for Xiaochaihu Granules, aiming to further improve the product quality.
Chromatography, High Pressure Liquid/methods* ; Drugs, Chinese Herbal/chemistry* ; Glycyrrhizic Acid/analysis* ; Rhizome/chemistry* ; Scutellaria baicalensis

The high performance liquid chromatography(HPLC) characteristic chromatogram of Xiaoer Ganmaoning Oral Liquid(oral liquid for short) was established. The medicinal materials corresponding to characteristic peaks, their index components and ranges of similarity with the reference chromatograms were clarified. The similarity between the characteristic chromatograms of 10 batches of the oral liquid and the reference chromatogram was higher than 0.994. Eighteen characteristic peaks were identified, which were derived from different medicinal materials including Scutellariae Radix, Arctii Fructus, Lonicerae Japonicae Flos, Gardeniae Fructus and Forsythiae Fructus. Further, 11 characteristic peaks were assigned by the comparison with reference substances as chlorogenic acid, neochlorogenic acid, cryptochlorogenic acid, isochlorogenic acid A, isochlorogenic acid C, baicalin, baicalein, wogonin, scutellarin, forsythiaside A and arctiin. Also, the characteristic chromatogram of precipitate in the oral liquid was established, and the similarity between characteristic chromatograms of 10 batches of the precipitate and the reference chromatogram was higher than 0.940. The 14 characteristic peaks originating from the precipitate and those from the oral liquid were consistent in retention time, and the content of all index components in the precipitate was lower than 5% of that in the oral liquid. Moreover, the stability of precipitate during the accelerated stability test was explored with filtration and Matlab-based image sensory evaluation. The precipitate mass and precipitation degree both increased over the stability test duration significantly. The stability of the oral liquid was used as a model system in this study to establish the integrated quality control system which related to medicinal materials, preparations and precipitate with HPLC characteristic chromatograms and image sensory evaluation, which lays a foundation for the exploration of the quantity value transfer of the oral liquid.
Chromatography, High Pressure Liquid/methods* ; Drugs, Chinese Herbal/chemistry* ; Quality Control ; Scutellaria baicalensis/chemistry*

OBJECTIVETo develop a quantitative method for simultaneously determining four flavones in Radix Scutellariae, by using one chemical standard substance.

METHODThe relative correction factors (RCF) of four flavones were determined by HPLC-DAD. Within the linear ranges, the values of RCF at 274 nm of wogonoside, baicalein, and wogonin to baicalin, were 0.7467, 0.5638, 0.4351, respectively. And the contents of baicalin in 27 samples of Scutellaria baicalensis were authentically determined by the external standard method, and the contents of the three other flavones were calculated according to their RCF. The contents of these four flavones in the all samples were determined with the external standard method.

RESULTThe RCF had a good reproducibility (RSD 0.66%-2.83%). No significant differences between the quantitative results by the above two methods were observed.

CONCLUSIONIt is a fast, convenient, and accurate method to determine multi-components especially when some authentic standard substances were unavailable. It can be used as a method to control the quality of Radix Scutellariae.

Chromatography, High Pressure Liquid ; Flavanones ; chemistry ; Flavones ; chemistry ; Flavonoids ; chemistry ; Glucosides ; chemistry ; Plant Extracts ; chemistry ; Scutellaria baicalensis ; chemistry