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Summary

The objective of the work was continuation of our study on identification of target coumarins in extracts from Peucedanum alsaticum L. and Peucedanum cervaria (L.) Lap., by use of ChromSword, on the basis of relationships between retention data and descriptors such as partial molecular volume of structural fragments in water and energies of electrostatic interactions of bond dipoles with water (QSRR). The coumarins were mainly identified by comparing UV spectra from gradient runs with spectra from the literature. The presence of columbianadin, ostruthin, and 8-methoxypeucedanin in the fruits of P. cervaria (L.) Lap. and oxypeucedanin and isoimperatorin in the fruits of P. alsaticum was confirmed. The optimum conditions obtained from DryLab simulation were used for both RP-HPLC and RP-UPLC.

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] developed a fast and sensitive, and selective UPLC-ESI-MS/MS method for the simultaneous quantitation of the concentrations of ten different flavonoids (scutellarin, scutellarein, chrysin, wogonin, baicalein, apigenin, wogonoside, oroxylin alpha-7- O

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(UPLC-MS/MS). 2 Experimental 2.1 Chemicals and reagents The reference standards for 3-O- α - l -rhamnopyranosyl-(1→2)- α - l -arabinopyranoside-29-hydroxy oleanolic acid (1), 3-O- β - d -glucopyranosyl-(1→2)- α - l -arabinopyranoside-29-hydroxy oleanolic

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Taxodione is the abietane diterpenoid, which has been earlier reported to show cytotoxic, antitumor, antibacterial, and antioxidant properties. This compound has been isolated from a genetically transformed root culture of Salvia austriaca. However, no method for taxodione quantification is yet available. A validated ultra-performance liquid chromatography-diode array detector (UPLC-DAD) method was developed for the quantification of taxodione in a hexane extract taken from genetically transformed roots of S. austriaca. The developed UPLC-DAD method demonstrated good linearity in the range 10–500 μg mL−1 (r 2 = 0.99988), high precision (relative standard deviation (RSD) <1.42%), and good repeatability (RSD <1.84%). The limits of detection and quantification of taxodione were found to be 0.48 ng and 1.60 ng, respectively. The recovery of taxodione ranged between 90.4 and 113.1%, and the RSD was less than 2.5%.The developed UPLC-DAD method was then used to determine the content of taxodione in various hairy root lines and changes in amount of the compound during the 50-day growth cycle of the culture. The content of taxodione in hairy root cultures of S. austriaca ranged from 0.29 to 1.12 mg g−1 dry weight depending on root line and stage of growth.

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A rapid method has been used for simultaneous identification of both hydrophilic and lipophilic compounds from Radix Salviae Miltiorrhizae (RSM, the root of Salvia miltiorrhiza BGE.) by ultra-performance liquid chromatography/quadrupole time-offlight mass spectrometry (UPLC/Q-TOF-MS). A total of 58 compounds extracted by methanol were detected and tentatively identified within 20 min, including hydrophilic phenolics, lipophilic diterpenoids, a verbascose, and several organic acids. These compounds were separated on an Acquity UPLC BEH C18 column and identified based on tandem mass spectrometry (MS/MS) fragmentation patterns under the positive and negative ion modes, respectively. Among them, micranthin B and 9-oxo-10E,12Zoctadecadienoic acid were reported in RSM for the first time. Their fragmentation patterns in electrospray ionization (ESI)—MS/MS spectra were first investigated by matching their accurate molecular masses. This contribution presented one of the first reports on the analysis of hydrophilic phenolics and lipophilic diterpenoids from Radix Salviae Miltiorrhizae using UPLC/Q-TOF-MS. The results demonstrated that UPLC/Q-TOF-MS method could be applied to rapidly and expediently describe and provide comprehensive chemical information for simultaneous analysis of two different polar components in RSM.

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Patrinia scabiosaefolia Fisch. (PSF), a well-known traditional Chinese medicine, has been demonstrated to show therapeutic effects on inflammatory bowel disease. In this study, a rapid and sensitive method using ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF-MS) was developed for identification of the major constituents in PSF. The separation analysis was performed on Waters Acquity UPLC system, and the accurate mass of molecules and their fragment ions were determined by Q-TOF-MS. Thirty-one constituents, including triterpenoids, iridoids, flavonoids, and organic acids were detected and tentatively deduced on the basis of their element compositions, tandem mass spectrometry (MS/MS) data, and relevant literatures. Twelve constituents were discovered for the first time in PSF. The results demonstrated that hederagenin-type and oleanolic acid-type saponins were the main constituents of PSF. Our work provides a certain foundation for further quantitation of major chemical constituents and in vivo pharmacokinetic studies of PSF. Moreover, the analytical approach developed herein has proven to be generally applicable for profiling the chemical constituents in traditional Chinese medicines (TCMs) and other complicated mixtures.

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Summary

In this research work comprehensive stress testing of irbesartan was carried out according to ICH guideline Q1A (R2), and a stability-indicating reversed-phase ultra-performance liquid chromatographic (UPLC) assay was established. The drug was subjected to acid (0.1 m HCl), neutral, and alkaline (0.1 m NaOH) hydrolytic conditions at 80°C, and to oxidative decomposition at room temperature. Photolysis was carried out by exposing the drug to sunlight (60,000–70,000 lux) for two days. The solid drug was also subjected to 50°C for 60 days in a hot-air oven. Degradation of the drug was found to occur under alkaline, acidic, and neutral hydrolytic conditions. Separation of the drug and the degradation products was successfully achieved on a BEH (bridged ethylene hybrid) C18 column with 40:60 aqueous glacial acetic acid (0.2%)-acetonitrile as mobile phase. The flow rate and detection wavelength were 0.1 mL min−1 and 229 nm, respectively. The method was validated and response was found to be linear in the drug concentration range 10–50 μg mL−1. The mean values (±RSD, %) of slope, intercept, and correlation coefficient were 32102 (± 0.0535), 1295 (± 3.02), and 0.9998 (± 0.0493), respectively. RSD in intra-day and inter-day precision studies was <1%. Recovery of the drug from a mixture of degradation products was between 99.26 and 100.01%. The method was specific to the drug, selective to degradation products, and robust. PDA purity test also confirmed the specificity of the method.

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A rapid and sensitive ultraperformance liquid chromatography-multiple reaction monitoring-multi-stage/mass spectrometry (UPLC-MRM-MS/MS) method has been developed for simultaneous quantification of salvianolic acid B and tanshinone IIA of salvia tropolone tablets in dog plasma. This was achieved by performing quantification using the MRM acquisition with two channels of MRM-MS/MS and MS full scan for more accuracy qualitative results, and the fragmentation transitions of m/z 295→249, 191 for tanshinone IIA and m/z 297→279, 251 for IS in positive mode, m/z 717→519, 321 for salvianolic acid B and m/z 295→267, 239 for IS in negative mode were selected. The UPLC separation was achieved within 3 min in a single UPLC run. Linear calibration curves were obtained over the concentration range of 10 pg/mL−1 ng/mL for tanshinone IIA and 100 pg/mL−1 for salvianolic acid B. Lower limit of quantitation (LLOQ) was 10 pg/mL and 100 pg/mL for tanshinone IIA and salvianolic acid B, respectively. The inter-day and intra-day precision (relative standard deviation, RSD) in all samples were less than 8.21%, and the recoveries were over 85.9% for both tanshinone IIA and salvianolic acid B. The two channels of MRM with MS full scan approach could provide both qualitative and quantitative results without the need for repetitive analyses and resulted in the reduction of further confirmation experiments and analytical time. The pharmacokinetic study of the two active components of salvia tropolone tablets following oral gavage administration of dogs was thus explored with this method.

Open access

Wheat glutenins containing high and low molecular weight glutenin subunits (HMW-GS and LMW-GS) are the major determinants of wheat gluten quality. In this study, the recently developed reversed-phase ultra-performance liquid chromatography (RP-UPLC) was used to study the synthesis and accumulation patterns of glutenins during grain development of four Chinese bread wheat cultivars with different gluten quality. Developing grains were collected based on thermal times from 150 °Cd to 750 °Cd at 100 °Cd intervals, and the content of glutenin subunits and their accumulation patterns were determined by RP-UPLC as well as sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The results showed that HMW-GS and LMW-GS synthesis were initiated currently at 250 °Cd and they displayed a gradually upregulated expression. All the HMW-GS can be detected at 250 °Cd, earlier than LMW-GS. Different glutenin subunits and genotypes showed clear accumulation diversity during grain development. Particularly, 1Dx5 + 1Dy10 in the cultivar Gaocheng 8901 and Zhongyou 9507 with superior dough properties were accumulated faster at early stages than 1Dx2 + 1Dy12 in Jingdong 8 and Zhengmai 9023 with poor dough quality, suggesting that faster accumulation rate of glutenin proteins at the early stages of grain development may contribute to the formation of superior gluten structure and dough quality.

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hydroxide solutions. UPLC–MS/MS Conditions Chromatographic analysis and quantitative evaluation were performed using a Waters ACQUITY UPLC system (Waters, Milford, MA) which consisted of a controller and two pumps

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