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81.
82.
Hui Zhang Jianan Wang Yan Chen Xiaowei Shen Huijie Jiang Xingchu Gong Jizhong Yan 《Journal of separation science》2019,42(6):1144-1154
A novel analytical quality by design approach for developing a chromatographic fingerprint was established for analyzing complex traditional Chinese medicine, using a licorice standard decoction as an example. Considering the characteristics of integrity and ambiguity, the resolution of eight common peaks, total peak number, capacity factor distributions, and peak purity were selected as potential critical method attributes for assessing the quality of the chromatographic fingerprint. A central composite design was used to evaluate the relationship between critical method attributes and critical method parameters, including column temperature, wavelength, flow rate, formic‐acid concentration, and gradient parameters. A standard probability method was employed to calculate the design space of the fingerprint analysis parameters and evaluate the robustness of the methodology. The optimized high‐performance liquid chromatography fingerprint conditions were acetonitrile and 0.1% formic acid water gradient elution (0‐5 min, 5–19% A; 5–10 min, 19% A; 10–50 min, 19–42% A; 50–54 min, 42–100% A; 54–60 min, 100% A), column temperature 25±5°C, detection wavelength 265 nm. The design space of fingerprint analytical method based on the analytical quality by design approach not only met the requirements of the fingerprint analysis, but also improved the robustness and applicability of the fingerprint method. 相似文献
83.
Cheng Qu Hui Yan Shao‐Qing Zhu Yi‐Yun Qian Gui‐Sheng Zhou Sheng Guo Zhen‐Hua Zhu Sen Zhang Da‐Wei Qian Jin‐Ao Duan 《Journal of separation science》2019,42(6):1122-1132
A rapid and sensitive ultra high performance liquid chromatography coupled to triple quadrupole tandem mass spectrometry method was established and employed to determine 21 nucleosides, nucleobases, and amino acids in 60 samples from different parts of Angelicae Sinensis Radix. The established methods were validated by good linearity (r2 > 0.9937), limits of detection (0.12–77.75 ng/mL), limits of quantitation (0.31–272.13 ng/mL), intra‐ and interday precisions (RSD ≤ 4.84%, RSD ≤ 6.26%), stability (RSD ≤ 5.92%), repeatability (RSD ≤ 7.14%), recovery (91.4–103.4%), and matrix effects (0.92–1.03). Chemical comparative analysis revealed that the content of total analytes in four parts of Angelicae Sinensis Radix were different, and exhibited the order: Head (14.89 mg/g) > Body (10.15 mg/g) > All (8.22 mg/g) > Tail (6.23 mg/g). Principal component analysis showed that the samples could be classified into four groups in accord with four different parts of Angelicae Sinensis Radix. The results could provide a scientific basis and reference for the quality control of Angelicae Sinensis Radix, and may be conducive to further research on the pharmacological activities of Angelicae Sinensis Radix. 相似文献
84.
Xiang Cui Yu‐meng Shen Shu Jiang Da‐wei Qian Er‐xin Shang Zhen‐hua Zhu Jin‐ao Duan 《Journal of separation science》2019,42(8):1520-1527
In this study, a rapid and highly sensitive ultra high performance liquid chromatography with triple quadrupole mass spectrometry method with the mobile phase of acetonitrile and 0.1% aqueous formic acid was established and successfully applied to comparatively analyze main active components after their compatibility. Besides, the effects of Scutellariae Radix, Coptidis Rhizoma and combined extracts on type 2 diabetic rats induced by high‐fat diet along with low dose of streptozocin were investigated. Under the optimized chromatographic conditions, good separation of seven target components was achieved within 12 min. All calibration curves exhibited good linearity (R2 ≥ 0.999). The relative standard deviation of precision, repeatability and stability varied from 0.69 to 2.23, 0.98 to 2.56, and 0.92 to 2.57%, respectively. The recovery ranged from 91.11 to 105.35%. The contents of seven active components were notably reduced after compatibility; however, the hypoglycemic effect of combined extracts was stronger than single drug by decreasing the activities of fructose‐1,6‐bisphosphatase, glucose 6‐phosphatase, phosphoenolpyruvate carboxykinase and increasing the activities of glucokinase, phosphofructokinase, pyruvate kinase. Accordingly, the established analytical method was accurate and sensitive enough for quantitative evaluation of seven investigated compounds. Moreover, the combined extract had definite effects on type 2 diabetes through multiple components against multiple targets. 相似文献
85.
Dan Dan Yin Yun Lai Wang Mo Yang Deng Ke Yin Guo Kai Wang Fan Xu 《Journal of separation science》2019,42(19):3067-3076
Ligustrazine was the active ingredient of the traditional Chinese medicine Chuanxiong Rhizoma. However, the content of ligustrazine is very low. We proposed a hypothesis that ligustrazine was produced by the mutual effects between endophytic Bacillus subtilis and the Ligusticum chuanxiong Hort. This study aimed to explore whether the endophytic B. subtilis LB5 could make use of Chuanxiong Rhizoma fermentation matrix to produce ligustrazine and clarify the mechanisms of action preliminarily. Ultra high performance liquid chromatography with quadrupole time‐of‐flight mass spectrometry analysis showed the content of ligustrazine in Chuanxiong Rhizoma was below the detection limit (0.1 ng/mL), while B. subtilis LB5 produced ligustrazine at the yield of 1.0268 mg/mL in the Chuanxiong Rhizoma‐ammonium sulfate fermentation medium. In the fermented matrix, the reducing sugar had a significant reduction from 12.034 to 2.424 mg/mL, and rough protein content increased from 2.239 to 4.361 mg/mL. Acetoin, the biosynthetic precursor of ligustrazine, was generated in the Chuanxiong Rhizoma‐Ammonium sulfate (151.2 mg/mL) fermentation medium. This result showed that the endophytic bacteria B. subtilis LB5 metabolized Chuanxiong Rhizoma via secreted protein to consume the sugar in Chuanxiong Rhizoma to produce a considerable amount of ligustrazine. Collectively, our preliminary research suggested that ligustrazine was the interaction product of endophyte, but not the secondary metabolite of Chuanxiong Rhizoma itself. 相似文献
86.
Minghui Qi Shiyi Zhao Bin Zhou Min Zhang Hongyang Zhang Yuerong Wang Ping Hu 《Journal of separation science》2019,42(23):3503-3511
Forsythiaside A is the major component of Forsythia suspensa. This study investigated the degradation mechanism of forsythiaside A. Eight degraded components including forsythiaside I, forsythiaside H, forsythiaside E, caffeic acid, suspensaside A, β‐hydroxy forsythiaside I, β‐hydroxy forsythiaside H, and β‐hydroxy forsythiaside A were identified by using ultra‐high performance liquid chromatography quadrupole time‐of‐flight mass spectrometry. Then, the quantitative analysis of multi‐components by a single‐marker was performed with ultra‐high performance liquid chromatography to simultaneously determine forsythiaside A, forsythiaside H, and forsythiaside I in Forsythia suspensa preparations. The result showed good linear relationships within 2.871–287.1, 0.231–23.1, and 0.983–98.3 μg/mL (r > 0.9998), with average recoveries of 97.7, 95.7, and 95.8% and relative standard deviations of 1.4, 2.4, and 1.8%, respectively. Using forsythiaside A as an internal reference, the relative retention values of forsythiaside H and forsythiaside I to forsythiaside A were calculated to be 0.89 and 0.61, respectively, and the relative correction factors were 0.816 and 0.799, respectively. The method for quantitative analysis of multi‐components by a single‐marker was applied to evaluate the overall quality of forsythia preparations. There was no significant difference in the measurement results of the method developed and the method of external standard. 相似文献
87.
Yining Zhao Zhangyao Xu Tianming Wang Yuanyuan Li Li Yang Shaoyong Liu Rong Shi Yueming Ma 《Biomedical chromatography : BMC》2019,33(7)
Tanreqing capsule (TRQC) is a formulation frequently used in traditional Chinese medicine to treat pyrexia, cough, expectoration and pharyngalgia. Since the pharmacological action of traditional Chinese medicines is closely related to their complex and diverse constituents, understanding the exact composition of TRQC is important to elucidate its clinical effectiveness and mechanism of action as well as to establish quality control methods and resolve safety issues. Herein, we employed high‐performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry for the simultaneous quantitation of 23 bioactive compounds in five batches of TRQC; the analytes could be categorized into five types: organic acids (seven compounds), flavonoids (10 compounds), iridoids (two compounds), phenylethanoid glycosides (two compounds) and bile acids (two compounds). The calibration curves for all analytes showed good linearity (r > 0.9953), and the inter‐ and intra‐day precisions did not exceed 4.94 and 4.97%, respectively. The recoveries varied from 90.47% to 109.80%; the corresponding relative standard deviations (RSDs) did not exceed 4.94%; and the repeatability (RSD < 4.72%) and stability (RSD < 4.88%) were also within acceptable limits. Thus, this study can be viewed as a fundamental reference for setting comprehensive TRQC quality standards. 相似文献
88.
Nasib Qureshi Patrick Karcher Michael Cotta Hans P. Blaschek 《Applied biochemistry and biotechnology》2004,114(1-3):713-721
Corn steep liquor (CSL), a byproduct of the corn wet-milling process, was used in an immobilized cell continuous biofilm reactor
to replace the expensive P2 medium ingredients. The use of CSL resulted in the production of 6.29 g/L of total acetone-butanol-ethanol
(ABE) as compared with 6.86 g/L in a control experiment. These studies were performed at a dilution rate of 0.32 h−1. The productivities in the control and CSL experiment were 2.19 and 2.01 g/(L·h), respectively. Although the use of CSL resulted
in a 10% decrease in productivity, it is viewed that its application would be economical compared to P2 medium. Hence, CSL
may be used to replace the P2 medium. It was also demonstrated that inclusion of butyrate into the feed was beneficial to
the butanol fermentation. A control experiment produced 4.77 g/L of total ABE, and the experiment with supplemented sodium
butyrate produced 5.70 g/L of total ABE. The butanol concentration increased from 3.14 to 4.04 g/L. Inclusion of acetate in
the feed medium of the immobilized cell biofilm reactor was not found to be beneficial for the ABE fermentation, as reported
for the batch ABE fermentation.
Names are necessary to report factually on available data. However, the USDA neither guarantees nor warrants the standard
of the product, and the use of the names by USDA implies no approval of the product to the exclusion of others that may also
be suitable. 相似文献
89.
《Journal of separation science》2018,41(5):1050-1062
Eucommiae Cortex is a classical traditional Chinese medicine, which needs to be processed by “sweating” methods. To select the suitable processing method and “sweating” processing condition for Eucommiae Cortex, in this study, the quality of Eucommiae Cortex was evaluated based on simultaneous determination of multiple bioactive constituents combined with gray relational analysis. The contents of lignans, iridoids, penylpropanoids, flavonoids, and phenols in samples were simultaneously determined using ultra‐fast performance liquid chromatography coupled with triple quadrupole‐linear ion trap tandem mass spectrometry. The chromatographic separation was performed on a Synergiۛ Hydro‐RP 100 Å column (100 mm × 2.0 mm, 2.5 μm) at 30°C with a gradient elution of acetonitrile with 0.1% formic acid/0.1% aqueous formic acid as the mobile phase. Furthermore, gray relational analysis was performed to evaluate and sort the samples according to the contents of 14 constituents by calculating the relative correlation degree of each sample. The results demonstrated that the quality of Eucommiae Cortex “sweating” at source area was better and the better “sweating” condition was to scrape off the cork layer before “sweating” with straw covering and sun drying. The developed method could provide the foundation and support for “sweating” processing method of Eucommiae Cortex in normalization and standardization. 相似文献
90.
Mohandas Devaki V. Whelan Douglas R. Panchal Chandra J. 《Applied biochemistry and biotechnology》1995,(1):307-318
Mutants resistant to comparatively high levels of acetic acid were isolated from the xylose-fermenting yeastsCandida shehatae andPichia stipitis by adapting these cultures to increasing concentrations of acetic acid grown in shake-flask cultures. These mutants were
tested for their ability to ferment xylose in presence of high acetic acid concentrations, in acid hydrolysates of wood, and
in hardwood spent sulfite liquor, and compared with their wild-type counterparts and between themselves. TheP. stipitis mutant exhibited faster fermentation times, better tolerance to acid hydrolysates, and tolerance to lower pH. 相似文献