Natural Deep Eutectic Solvents for the Extraction of Bioactive Steroidal Saponins from Dioscoreae Nipponicae Rhizoma

In the present study, a simple and environmentally friendly extraction method based on natural deep eutectic solvents (NADESs) was established to extract four bioactive steroidal saponins from Dioscoreae Nipponicae Rhizoma (DNR). A total of twenty-one types of choline chloride, betaine, and L-proline based NADESs were tailored, and the NADES composed of 1:1 molar ratio of choline chloride and malonic acid showed the best extraction efficiency for the four steroidal saponins compared with other NADESs. Then, the extraction parameters for extraction of steroidal saponins by selected tailor-made NADES were optimized using response surface methodology and the optimal extraction conditions are extraction time, 23.5 min; liquid–solid ratio, 57.5 mL/g; and water content, 54%. The microstructure of the DNR powder before and after ultrasonic extraction by conventional solvents (water and methanol) and the selected NADES were observed using field emission scanning electron microscope. In addition, the four steroidal saponins were recovered from NADESs by D101 macroporous resin with a satisfactory recovery yield between 67.27% and 79.90%. The present research demonstrates that NADESs are a suitable green media for the extraction of the bioactive steroidal saponins from DNR, and have a great potential as possible alternatives to organic solvents for efficiently extracting bioactive compounds from natural products.     

Simultaneous determination of six active components by a single standard to determine multicomponents combined with fingerprint analysis for the quality control of Rhizoma Chuanxiong

To control the quality of Rhizoma Chuanxiong, a method based on high‐performance liquid chromatography method coupled with diode array detection was developed for the quantitative analysis of six active ingredients using a single standard to determine multi‐components and chemical fingerprint analysis for the first time. The separation was performed on an Agilent Zorbax SB‐C₁₈ column by gradient elution with methanol and aqueous phase (containing 0.5% glacial acetic acid) at a flow rate of 1.0 mL/min. The UV wavelength was set at 274 nm. This assay was fully validated with respect to precision, repeatability, and accuracy. All calibration curves showed good linearity (R²> 0.9994) within test ranges. The limit of detection and limit of quantification were lower than 0.01 and 0.03 μg/mL, respectively. The relative standard deviation for repeatability and the intermediate precision of six analytes were less than 1.6 and 2.5%, respectively, the overall recovery was 96.1–103.1%. In addition, fingerprint chromatography using hierarchical clustering analysis and similarity analysis was performed to differentiate and classify the samples. The method described here could provide a more comprehensive and reasonable scientific assessment of the quality of Rhizoma Chuanxiong. Therefore, the strategy is feasible, credible, and is easily and effectively adapted for evaluating the quality control of Rhizoma Chuanxiong.     

山药近红外拉曼光谱分析

采用785 nm半导体激光光源,全息光栅和近红外增强CCD探测器等光电器件,构建了一套近红外拉曼光谱探测系统,测试获得了山药的拉曼光谱及拉曼一阶导数谱。山药拉曼光谱谱中出现了477, 863, 936 cm-1等较强的特征峰,主要归属为蛋白质、氨基酸、淀粉、多糖等物质,与已知山药生化成分基本相符。在山药拉曼一阶导数谱中,467,484,870,943 cm-1处出现明显特征峰。对比山药拉曼光谱,在600～800 cm-1,1 000～1 400 cm-1区域内,山药拉曼一阶导数谱变化较为明显,可以更为清晰地表现山药拉曼光谱,能作为山药拉曼光谱分析的补充方法。     

半夏淀粉的理化特性

研究了不同产地的4种半夏淀粉的理化特性,包括直链淀粉含量、膨胀度、溶解性、持水性、淀粉粒大小和形貌、结晶类型、热特性和糊化特性等。结果表明,这些半夏淀粉中直链淀粉含量为18.60%～23.91%;膨胀度21.53%～23.09%;溶解度11.5%～32.3%;持水性100.3%～119.0%。淀粉粒单粒球形,卵形或圆半球形,直径2～20μm,复粒由2～3个分粒组成,其结晶类型均为C型,结晶度15.0%～37.9%。用差示扫描量热仪测得的转变温度TO、TP和TC分别为71.58～77.75℃、83.03～83.84℃和89.41～90.99℃,热焓为4.316～5.809 J/g。用快速粘度分析仪测定了4种半夏淀粉的糊化特征值:峰值粘度、热糊粘度、冷糊粘度、稀懈值和回复值分别为149.5～226.2、97.7～127.2、141.8～194.3、50.4～99.0和44.2～67.2 RVU。糊化温度77.8～79.9℃,峰值时间8.3～8.7 min。     

Identification and quantification of atractylenolide I and atractylenolide III in Rhizoma Atractylodes Macrocephala by liquid chromatography–ion trap mass spectrometry

Rhizoma Atractylodes Macrocephala (RAM) is an important traditional Chinese medicinal herb that is used for treatment of dyspepsia and anorexia. The active ingredients, atractylenolide I (AO‐I) and atractylenolide III (AO‐III), were identified by direct‐injection ion trap‐mass spectrometry (IT‐MS) for collecting MSⁿ spectra. The major fragment ions of AO‐I and AO‐III were confirmed by MSⁿ both in negative ion mode and in positive ion mode. The possible main cleavage pathway of fragment ions was studied. The determinations of AO‐I and AO‐III were accomplished by liquid chromatography (LC) with UV and MS. The analytes provided good signals corresponding to the protonated molecular ions [M + H]⁺ and product ions. The precursor ions and product ions for quantification of AO‐III and AO‐I were m/z 249 → 231 and m/z 233 → 215, respectively, using selected ion monitoring by LC‐IT‐MS. Two methods were evaluated for a number of validation characteristics (repeatability, limit of detection, calibration range, and recovery). MS provides a high selectivity and sensitivity for determination of AO‐III and AO‐I in positive mode. After optimization of the methods, separation, identification and quantification of the two components in RAM were comprehensively tested by HPLC with UV and MS. Copyright © 2012 John Wiley & Sons, Ltd.     

Discrimination of Rhizoma Corydalis from two sources by near-infrared spectroscopy supported by the wavelet transform and least-squares support vector machine methods

Near-infrared spectroscopy (NIRS) was applied for direct and rapid collection of characteristic spectra from Rhizoma Corydalis, a common traditional Chinese medicine (TCM), with the aim of developing a method for the classification of such substances according to their geographical origin. The powdered form of the TCM was collected from two such different sources, and their NIR spectra were pretreated by the wavelet transform (WT) method. A training set of such Rhizoma Corydalis spectral objects was modeled with the use of the least-squares support vector machines (LS-SVM), radial basis function artificial neural networks (RBF-ANN), partial least-squares discriminant analysis (PLS-DA) and K-nearest neighbors (KNN) methods. All the four chemometrics models performed reasonably on the basis of spectral recognition and prediction criteria, and the LS-SVM method performed best with over 95% success on both criteria. Generally, there are no statistically significant differences in all these four methods. Thus, the NIR spectroscopic method supported by all the four chemometrics models, especially the LS-SVM, are recommended for application to classify TCM, Rhizoma Corydalis, samples according to their geographical origin.     

Ultra-performance LC-photodiode array-eλ-ESI-MS/MS screening method for the detection of radical-scavenging natural antioxidants from radix et rhizoma Rhei

A novel ultra-performance LC-photodiode array-el-ESI-MS/MS screening method was developed for the detection and identification of natural antioxidants from radix et rhizoma Rhei. Nine compounds were found to possess a potential antioxidant activity, and their free radical-scavenging capacities were investigated in detail. The nine compounds were identified as 1-O-galloyl-2-O-cinnamoylglucose, 6-hydroxymusizin-8-O-β-D-glucopyranoside, (+)-catechin, gallic acid 3-O-β-D-glucopyranoside, trans-3,5,4'-trihydroxystilbene- 4'-O-β-D-(2"-O-galloyl)-glucopyranoside, sennoside A, 4-(4'-hydroxyphenyl)-2- butanone-4'-O-β-D-(2"-O-galloyl-6"-O-p-coumaroyl) glucopyranoside, emodin-8-O-(6'-Omalonyl) glucopyranoside, and physcion-8-O-β-D-glucopyranoside. The reactivity and SC(50) values of those compounds were investigated, respectively. 1-O-Galloyl-2-O-cinnamoylglucose showed the strongest capability for scavenging 1,1-diphenyl-2-picrylhydrazylfree radical; trans-3,5,4'-trihydroxystilbene-4'-O-β-D-(2"-O-galloyl) glucopyranoside showed the strongest capability for scavenging superoxide radical; 4-(4'-hydroxyphenyl)-2-butanone- 4'-O-2-D-(2"-O-galloyl-6"-O-p-coumaroyl) glucopyranoside exhibited the highest reactivity in the lipid peroxidation processes. The use of the analytical screening method based on ultra-performance LC-photodiode array-el-ESI-MS/MS would provide a new way for rapid detection of radical-scavenging natural compounds from radix et rhizoma Rhei or complex matrices.     

Quantitative evaluation main of the components in Paeoniae Radix Alba–Atractylodis Macrocephalae Rhizoma herbal pair by high‐performance liquid chromatography

The aim of this study was to investigate the influence of compatibility on the contents of main compounds in Paeoniae Radix Alba and Atractylodis Macrocephalae Rhizoma. Ten compounds were separated on an Inertsil ODS‐SP Extend C₁₈ column (250 mm × 4.6 mm, 5 μm) and detected by a diode array detector with the mobile phase consisting of aqueous phosphoric acid (0.1%, v/v; A) and acetonitrile (B) by linear gradient elution. All analytes showed good linearity over a wide concentration range (r² ≥ 0.9989). The limits of detection and quantification were <8.10 and 10.80 μg/mL, respectively. The intra‐ and interday variations were <4.36%. The average recoveries were observed from 94.90 to 103.38%, with relative standard deviation ranging from 1.23 to 3.15% for the analytes. The established method was reliable enough for global quality evaluation of Paeoniae Radix Alba, Atractylodis Macrocephalae Rhizoma, and their co‐decoctions.     

Discrimination of Acori Tatarinowii Rhizoma and Acori Calami Rhizoma based on quantitative gas chromatographic fingerprints and chemometric methods

This study was conducted to investigate the chemical differences between Acori Tatarinowii Rhizoma and Acori Calami Rhizoma using gas chromatography with mass spectrometry and chemometric methods. Quantitative fingerprints were established. A total of 90 volatile compounds were identified and quantified using heuristic evolving latent projection and retention index. An efficient model based on partial least squares‐discriminant analysis coupled with variable iterative space shrinkage approach was developed to distinguish Acori Tatarinowii Rhizoma from Acori Calami Rhizoma. The correct rate was 95.83%, and the area under the receiver operating characteristic curve was 100%. Finally, three volatiles, namely, camphor, longicyclene, and δ‐cadinene, were selected as key discrimination factors between Acori Tatarinowii Rhizoma and Acori Calami Rhizoma. The proposed protocol can serve as a valid strategy for quality control and screening of potential bioactive components of herbal medicines.     

Approach based on high‐performance liquid chromatography fingerprint coupled with multivariate statistical analysis for the quality evaluation of Gastrodia Rhizoma

Gastrodia Rhizoma is a Traditional Chinese Medicine applied in the treatment of stroke, numbness of limb, headache and dizziness. However, its clinical effect is threatened by sulfur‐fumigation used in the process of storage. This article employs content determination coupled with high‐performance liquid chromatography fingerprint to investigate the effect of sulfur‐fumigation on Gastrodia Rhizoma so as to evaluate the quality of Gastrodia Rhizoma. The result was that most active ingredient in Gastrodia Rhizoma decreased after sulfur‐fumigation and the fingerprints analyzed by mathematical statistics between sulfur‐fumigated Gastrodia Rhizoma and unfumigated Gastrodia Rhizoma have substantial differences, which reveals that sulfur‐fumigation has a significant influence on the quality of Gastrodia Rhizoma. The conclusion of hierarchical clustering analysis, principal component analysis and partial least squares could validate each other, which implies that the method of mathematical statistics applied for assessing the quality of Gastrodia Rhizoma is effective and stable. The method not only affords a viable strategy for distinguishing Gastrodia Rhizoma whether sulfur‐fumigated or not and assessment of the quality of Gastrodia Rhizoma, but also provides a reference for other herbal medicine that suffers from sulfur‐fumigation.