Study on quality control methods and pharmacodynamic material basis of different specifications of Corydalis Rhizoma produced in Zhejiang Province.

ETHNOPHARMACOLOGICAL RELEVANCE: The quality control methods of different specifications of Corydalis Rhizoma in Zhejiang China (ZJ CR) are the same, so the quality of each specification couldnot be guaranteed. To clarify the quality control methods and pharmacodynamic material basis of ZJ CR with different specifications could provide reference for the quality control of ZJ CR. AIM OF THE STUDY: The purpose of this study was to establish a quality control method for ZJ CR with different specifications and to screen out the pharmacodynamic material basis of ZJ CR with different specifications. MATERIALS AND METHODS: Firstly, according to the existing grading standards, the medicinal materials were divided into specifications, and the character indexes of ZJ CR with different specifications were established. The quality indexes were established by HPLC, network pharmacology and literature retrieval. The correlation between the trait indexes and quality indexes of ZJ CR with different specifications was analyzed, and the best quality control method was established. Further combined with the pharmacodynamic indexes of ZJ CR with different specifications, the pharmacodynamic material basis of ZJ CR with different specifications was screened out by spectrum-effect analysis. The correlation between trait indexes and pharmacodynamic indexes was analyzed to verify the rationality of grade standard. RESULTS: The three specifications of ZJ CR were CR (Diameter ≥1.1 cm), CR (Diameter <1.1 cm), and CR (No size distinction). Diameter, width, thickness, grain weight, volume and 50 g grain number could be used as the trait indexes of ZJ CR. Protopine (CR1), palmatine hydrochloride (CR2), berberine hydrochloride (CR3), dehydrocorydaline (CR4), tetrahydropalmatine (CR5), tetrahydroberberine (CR6), corydaline (CR7), stylopine (CR8) and isoimperatorin (CR9) were identified. Total components, core components (CR5, CR6, CR7 and CR8), alcohol-soluble extracts (ASE) could be used as quality indexes. The best quality control methods of the three specifications respectively were: the larger the diameter and grain weight, the smaller the number of 50 g grains; The larger the diameter, the smaller the volume, thickness, width and number of 50 g particles; The larger the grain weight and volume, the smaller the number of 50 g grains. The main analgesic components of the three specifications respectively were: CR1, CR2 and core components; CR2, CR4; CR8, CR9. The larger the diameter and the less the number of 50 g grains, the better the analgesic effect of ZJ CR, and the grade standard was reasonable. CONCLUSIONS: This study showed that the quality control methods and pharmacodynamic material basis of ZJ CR with different specifications were different, which may be caused by the differences in traits and the contribution of main active ingredients. This study constructed an evaluation model combining external traits, internal quality and overall efficacy, and provided theoretical support for the rationality of ZJ CR grade standard.

Identification of Photocatalytic Alkaloids from Coptidis Rhizome by an Offline HPLC/CC/SCD Approach.

Natural products continue to be a valuable source of active metabolites; however, researchers of natural products are mostly focused on the biological effects, and their chemical utility has been less explored. Furthermore, low throughput is a bottleneck for classical natural product research. In this work, a new offline HPLC/CC/SCD (high performance liquid chromatography followed by co-crystallization and single crystal diffraction) workflow was developed that greatly expedites the discovery of active compounds from crude natural product extracts. The photoactive total alkaloids of the herbal medicine Coptidis rhizome were firstly separated by HPLC, and the individual peaks were collected. A suitable coformer was screened by adding it to the individual peak solution and observing the precipitation, which was then redissolved and used for co-crystallization. Seven new co-crystals were obtained, and all the single crystals were subjected to X-ray diffraction analysis. The molecular structures of seven alkaloids from milligrams of crude extract were resolved within three days. NDS greatly decreases the required crystallization amounts of alkaloids to the nanoscale and enables rapid stoichiometric inclusion of all the major alkaloids with full occupancy, typically without disorder, affording well-refined structures. It is noteworthy that anomalous scattering by the coformer sulfur atoms enables reliable assignment of absolute configuration of stereogenic centers. Moreover, the identified alkaloids were firstly found to be photocatalysts for the green synthesis of benzimidazoles. This study demonstrates a new and green phytochemical workflow that can greatly accelerate natural product discovery from complex samples.

Computational Prediction and Experimental Validation of the Unique Molecular Mode of Action of Scoulerine.

Scoulerine is a natural compound that is known to bind to tubulin and has anti-mitotic properties demonstrated in various cancer cells. Its molecular mode of action has not been precisely known. In this work, we perform computational prediction and experimental validation of the mode of action of scoulerine. Based on the existing data in the Protein Data Bank (PDB) and using homology modeling, we create human tubulin structures corresponding to both free tubulin dimers and tubulin in a microtubule. We then perform docking of the optimized structure of scoulerine and find the highest affinity binding sites located in both the free tubulin and in a microtubule. We conclude that binding in the vicinity of the colchicine binding site and near the laulimalide binding site are the most likely locations for scoulerine interacting with tubulin. Thermophoresis assays using scoulerine and tubulin in both free and polymerized form confirm these computational predictions. We conclude that scoulerine exhibits a unique property of a dual mode of action with both microtubule stabilization and tubulin polymerization inhibition, both of which have similar affinity values.

UHPLC With On-Line Coupled Biochemical Detection for High Throughput Screening of Acetylcholinesterase Inhibitors in Coptidis Rhizoma and Cortex Phellodendri.

We developed a new on-line method of ultra-performance liquid chromatography coupled with biochemical detection (UHPLC-BCD) to screen acetylcholinesterase (AChE) inhibitors in complex matrixes. Chromatography separation was performed using an Xtimate UHPLC C18 column (100 mm × 2.1 mm, 1.8 µm) and a gradient elution with methanol-0.1% formic acid at a flow rate of 0.08 mL/min. The BCD was based on a colorimetric method using Ellman's reagent, and the detection wavelength was at 405 nm. Galanthamine was used as a positive reference to validate the methodology. The detection and quantitation limits of the UHPLC-BCD method were 0.018 and 0.060 µg, respectively. A functional equation was generated in terms of the negative peak area (X) and galanthamine concentration (Y, µg/mL). The regression equation was Y = 0.0028X2 + 0.4574X + 50.7776, R2 = 0.9993. UHPLC-fourier-transform mass spectrometry detection results revealed that five alkaloids showed obvious AChE inhibitory activities including coptisin, epiberberine, jatrorrhizine, berberine and palmatine. The relative AChE inhibitory activities of jatrorrhizine, berberine and palmatine in the Coptidis Rhizoma sample were equal to that of 257.0, 2355 and 283.9 µg/mL of galanthamine, respectively. This work demonstrated that the UHPLC-BCD method was convenient and feasible, and could be widely used for the screening and activity evaluation of the bioactive components in the complex extracts.

Jatrorrhizine reduces myocardial infarction-induced apoptosis and fibrosis through inhibiting p53 and TGF-ß1/Smad2/3 pathways in mice

Purpose: To explore the mechanism of jatrorrhizine on apoptosis and fibrosis induced by myocardial infarction (MI) in an animal model. Methods: The left anterior descending branch of coronary artery was surgically ligated to duplicate the mouse model of MI. The sham and infarcted mice were treated with normal saline once a day, while mice in experimental groups received low-dose (LD) and high-dose (HD) jatrorrhizine once a day respectively. Two weeks later, cardiac function was detected by echocardiography, and histopathological examination was performed using hematoxylin and eosin (H&E) and Masson staining. The expressions of p53, TGF-ß1, Smad/2/3, Bax, Bcl-2, collagen I and collagen III were quantified using qRT-PCR and western blot assays. Results: Jatrorrhizine significantly improved left ventricular ejection fraction (LVEF) and left ventricle end-systolic (LVES) in mice. Histopathological, administration of jatrorrhizine weakened infiltration of inflammatory cells and cardiac fibrosis in myocardium of mice caused by MI. Additionally, jatrorrhizine suppressed cardiomyocyte apoptosis exhibited as its capability to reverse changes of Bax and Bcl-2 levels in myocardium caused by MI. Jatrorrhizine statistically significantly downregulated expression of collagen I and collagen III, as well as TGF-ß1, Smad2/3 and p53. Conclusions: Jatrorrhizine reduce cardiomyocyte apoptosis and fibrosis through inhibiting p53/Bax/Bcl-2 and TGF-ß1/Smad2/3 signaling pathways.

Biological Response Profiling Reveals the Functional Differences of Main Alkaloids in Rhizoma Coptidis.

Rhizoma Coptidis (RC) is a widely used traditional Chinese medicine. Although modern research has found that some alkaloids from RC are the pharmacologically active constituents, the differences in their biological effects are not completely clear. This study analyzed the differences in the typical alkaloids in RC at a systematic level and provided comprehensive information on the pharmaceutical mechanisms of the different alkaloids. The ethanol RC extract (RCE) was characterized using HPLC assay. HepG2, 3T3-L1, and RAW264.7 cells were used to detect the cytotoxicity of alkaloids. Transcriptome analyses were performed to elucidate the cellular pathways affected by RCE and alkaloids. HPLC analysis revealed that the typical alkaloids of RCE were berberine, coptisine, and palmatine. Coptisine and berberine displayed a stronger inhibitory effect on cell proliferation than palmatine. The overlapping ratios of differentially expressed genes between RCE and berberine, coptisine, and palmatine were 70.8%, 52.6%, and 42.1%, respectively. Pathway clustering analysis indicated that berberine and coptisine possessed a certain similarity to RCE, and both compounds affected the cell cycle pathway; moreover, some pathways were uniquely enriched by berberine or coptisine. Berberine and coptisine had different regulatory effects on genes involved in lipid metabolism. These results provide comprehensive information on the pharmaceutical mechanisms of the different RC alkaloids and insights into their better combinatory use for the treatment of diseases.

A new strategy for quality evaluation and control of Chinese patent medicine based on chiral isomer ratio analysis: With Yuanhuzhitong tablet as an example.

Chiral compounds commonly exist in traditional Chinese medicine (TCM), but little research on the quality control of TCM has been conducted. In this study, a new strategy is proposed, taking Yuanhuzhitong tablet [YHZT, consisting of Radix Angelicae Dahuricae and Rhizoma Corydalis (Yan Hu Suo, YHS)] for example, which is based on chiral isomer ratio analysis to monitor the production process of Chinese patent medicine companies. In the process of content determination for tetrahydropalmatine (THP) in YHZT from different companies, noticeable differences were observed in their chromatographic behaviors. It is known that THP has two enantiomers, naturally coexisting in YHS as a racemic mixture, so we prepared THP twice and subsequently performed chiral separation analysis using supercritical fluid chromatography. As a result, the peak area ratios of two enantiomers from different companies varied remarkably, demonstrating that some companies did not probably manufacture YHZT products in accordance with the prescription proportion, used inferior or extracted YSH crude materials in the production process, and added raw chemical medicine in the production to reach the standard and lower the costs. In conclusion, the peak area ratio of chiral isomers could be taken as a key quality index.

Pharmacokinetic study of three different formulations of l-tetrahydropalmatine in brain tissues of rats.

l-Tetrahydropalmatine (l-THP), an active alkaloid compound isolated from Rhizoma Corydalis-yanhusuo, has been reported to possess biological activity for treating cocaine use. To enhance both oral bioavailability and brain penetration, three formulations of l-THP suspension, mixture of l-THP-puerarin and self-microemulsifying drug delivery systems (SMEDDS) were prepared. A sensitive and reliable ultra-high-performance liquid chromatography with tandem mass spectrometry method was developed and validated for the simultaneous determination of l-THP and its active metabolite l-isocorypalmine (l-ICP) in rat brain. Diazepam was used as the internal standard. The chromatographic separation was achieved on a Bonshell ASB C18 column at 30°C using acetonitrile-aqueous formic acid as mobile phase in gradient mode. The linearity was validated over the concentration ranges of 4.00-2,500 ng/ml for l-THP and 0.400-500 ng/ml for l-ICP. Full method validation was within the acceptance limits. The method was successfully used to determine the pharmacokinetics of two analytes following oral administration of these three formulations to rats. A significant difference was observed in the main pharmacokinetic parameters between SMEDDS and the suspension, and a 3.25- and 2.97-fold increase in the relative bioavailability of l-THP and l-ICP, respectively, was observed with the SMEDDS compared with the suspension formulation. It was concluded that SMEDDS enhanced the absorption of l-THP and l-ICP and delayed their release in brain.

Chemical Evaluation of the Effects of Storage Conditions on the Botanical Goldenseal using Marker-based and Metabolomics Approaches.

Hydrastis canadensis, commonly known as goldenseal, is a botanical native to the southeastern United States that has been used for the treatment of infection. The activity of goldenseal is often attributed to the presence of alkaloids (cyclic, nitrogen-containing compounds) present within its roots. Chemical components of botanical supplements like goldenseal may face degradation if not stored properly. The purpose of the research was to analyze the stability of known and unknown metabolites of H. canadensis during exposure to different storage conditions using mass spectrometry. Three abundant metabolites of H. canadensis, berberine, canadine, and hydrastine, were chosen for targeted analysis, and the stability of unknown metabolites was evaluated using untargeted metabolomics. The analysis and evaluation of H. canadensis samples were performed utilizing LC-MS and Principal Component Analysis (PCA). The research project focused on identifying the chemical changes in the metabolite content of H. canadensis under different temperature conditions (40°C ± 5°C, 20°C ± 5°C , and 4°C ± 5°C), different light:dark (hr:hr) cycles (16:8, 12:12, and 0:24), and different sample conditions (powdered roots versus whole roots) over a six month period. The results of this 6-month study revealed that the storage conditions evaluated had no significant effects on the chemical composition of H. canadensis roots. Hence, as long as H. canadensis roots are stored within the storage conditions tested in the study, no significant changes in chemical compositions of metabolites are expected.

Enantioselective analysis in complex matrices using capillary electrophoresis-mass spectrometry: A case study of the botanical drug Corydalis Rhizoma.

Enantioselective analysis is critically important in the pharmaceutical and agricultural industries. However, most of the methods reported were developed for the analysis of pure racemates acquired from chemical synthesis or purification. Direct analysis of chiral enantiomers in complex matrices has rarely been reported. This work demonstrated capillary electrophoresis-mass spectrometry (CE-MS) for the enantioselective analysis of botanical drugs for the first time, using a widely used botanical drug, Corydalis Rhizoma, as an example. The method was used for the simultaneous enantioselective analysis of dl-tetrahydropalmatine and (RS)-tetrahydroberberine (canadine) in Corydalis Rhizoma extract. Using (2-hydroxypropyl)-ß-cyclodextrin as the chiral selector, a partial filling technique was used to avoid signal suppression and contamination of the MS detector. Post column organic modifier was used to assist with ionization in the flow through microvial CE-MS interface, therefore, organic solvents was not used in the background electrolyte. The completely aqueous background electrolyte contributed to better chiral separations. The CE-MS method established here can directly determine the analytes in their complex matrix without any pre-purification steps, while also offering high sensitivity and low operational costs (including sample, chiral selector and solvent). In the method validation process, good linearity (r > 0.993), sensitivity and accuracy (recoveries within 89.1-110.0%) were demonstrated. The CE-MS technique was shown to be able to provide good selectivity for the simultaneous chiral separation of multiple pairs of enantiomers in complex matrices.

Pharmacokinetics and tissue distribution of four major bioactive components in rats after oral administration of Xianglian pill.

Xianglian pill, a TCM prescription, consists of Rhizome Coptidis and Radix Aucklandiae, and has been used to treat gastrointestinal disease for many years. Berberine, jatrorrhizin, coptisine and palmatine are four representative alkaloids in Xianglian pill. Knowing that the drug disposal process in vivo is closely related to the toxicity and efficacy of a drug, it is important to classify the disposal properties of these alkaloids. In this study, the pharmacokinetics and tissue distribution of the four alkaloids were investigated. The analytical samples were analyzed using a validated HPLC-MS/MS method. The results showed that the four alkaloids could be slowly absorbed. The Cmax values of berberine, jatrorrhizin, coptisine and palmatine were 11.420, 2.287, 2.584 and 3.102 ng/ml, respectively. Subsequently, the tissue distribution studies showed that they were quickly distributed to various tissues with rich blood flow in the body.

Berberina, curcumina y quercetina como potenciales agentes con capacidad antiparasitaria / Berberine, curcumin and quercetin as potential antiparasitic agents

Introducción: El uso indiscriminado de agentes antiparasitarios ha resultado en el establecimiento de resistencia a ellos. Por lo cual es necesario el desarrollo de nuevas alternativas de tratamiento. Los productos naturales poseen diversas cualidades como posibles coadyuvantes en terapias contra distintos agentes etiológicos, entre los que destaca sus efectos antiparasitarios. Objetivo: Evaluar la actividad antiparasitaria, antioxidante, citotóxica y citoprotectora de Berberina (Ber), Curcumina (Cur) y Quercetina (Qr). Metodología: Se prepararon soluciones de Ber, Cur y Qr grado analítico y se realizaron alícuotas a diferentes concentraciones para su evaluación en contra de: Entamoeba histolytica, Trichomonas vaginalis y Strongyloides venezuelensis, paraello, se determinó la concentración inhibitoria media (IC50), además se determinó la capacidad antioxidante (CE50) mediante la prueba de DPPH, ambos por la prueba de Probit. Mediante la técnica de hemólisis se determinó la actividad citotóxica y citoprotectora, se aplicó Anova y la prueba de Tukey para determinar la diferencia de las medias en los tratamientos evaluados. Resultados: Ber, Cur y Qr, presentaron actividad en contra de E. histolytica, T. vaginalis y S. venezuelensis in-vitro. Ber presentó IC50 de 1.7, 1.2 y 1.9 μM respectivamente siendo más efectivo en comparación de Cur con IC50 de 55.3, 40.6 y 13.7 μM o Qr con IC50 de 147.2, 93.2 y 110.9 μM, sin embargo, la mejor actividad antioxidante (EC50 = 1.1 μg/ml), citoprotectora y menos hemolítica, fue presentada por Qr (P < 0.001) en comparación con el control evaluado. Conclusiones: Los metabolitos de origen natural berberina, curcumina y quercetina, poseen actividad en contra de trofozoítos de E. histolytica, T. vaginalisy larvas de S. venezuelensis en dosis bajas comparables con los fármacos de referencia para el caso de Ber. Además, estos productos de origen natural, no sintético podrían ser objeto de futuras investigaciones para coadyuvar al tratamiento de parasitosis, ya que, en dosis bajas, mostraron actividad antioxidante sin mostrar hemólisis considerable en eritrocitos humanos.

Introduction: The indiscriminate use of antiparasitic agents has resulted in the establishment of resistance to them. Therefore, the development of new treatment alternatives is necessary. Natural products have various qualities as possible adjuvants in therapies against different etiological agents, among which its antiparasitic effects stand out. Objective: To evaluate the antiparasitic, antioxidant, cytotoxic, and cytoprotective activity of Berberine (Ber), Curcumin (Cur), and Quercetin (Qr). Methods: Analytical grade Ber, Cur, and Qr solutions were prepared, and aliquots were made at different concentrations for their evaluation against Entamoeba histolytica, Trichomonas vaginalis, and Strongyloides venezuelensis. To do this, the mean inhibitory concentration (IC50) was determined, and the antioxidant capacity (EC50) was also determined by the DPPH assay, both using the Probit statistical test. The cytotoxic and cytoprotective activity was determined by the hemolysis technique, Anova and Tukey's test were applied to determine the difference in the means in the treatments evaluated. Results: Ber, Cur, and Qr, showed activity against E. histolytica, T. vaginalis, and S. venezuelensisin-vitro. Ber presented IC50 of 1.7, 1.2, and 1.9 μM respectively, being more effective compared to Cur with IC50 of 55.3, 40.6, and 13.7 μM, or Qr with IC50 of 147.2, 93.2, and 110.9 μM, however, the best antioxidant activity (EC50 = 1.1 μg/ml), cytoprotective and less hemolytic, was presented by Qr (P < 0.001) compared to the evaluated control. Conclusions: The metabolites of natural origin berberine, curcumin, and quercetin, have activity against trophozoites of E. histolytica, T. vaginalis and larvae of S. venezuelensis in low doses comparable to the reference drugs in the case of Ber. Furthermore, these non-synthetic products of natural origin could be the subject of future research to help treat parasitosis, since in low doses, they showed antioxidant activity without showing considerable cytotoxicity in human erythrocytes.

[Simultaneous Quantitative Analysis of Berberine and Other Alkaloids in Powdered Phellodendron Bark].

Phellodendron bark ("Obaku") is an important crude drug used in Kampo-medicine. Recently, powder formulation of phellodendron bark was approved as an "efficacious treatment for bruise, sprain, and periodontal diseases", and it has been marketed as an OTC agent. To obtain this approval, the examination of quality control-related characteristics is necessary. Therefore, we established a quantitative method for jatrorrhizine, palmatine, and berberine determination. In this study, we compared the contents of the three constituents obtained from the extracts of Japanese and Chinese phellodendron bark and found remarkable difference.

Screening of bioactive components from traditional Chinese medicine by immobilized ß2 adrenergic receptor coupled with high performance liquid chromatography/mass spectrometry.

Traditional Chinese medicine (TCM) represents a valuable resource for lead compounds discovery. Given the complexity of TCM components, analytical methods play a key role in novel drug development. In our study, we established a high specific and reliable bio-active components screen system, where ß2 adrenergic receptor (ß2-AR) was immobilized on silica by non-covalent bonds and packed into a stainless steel column (4.6 × 50 mm, 7 µm) to form ß2-AR chromatography column. The column was further coupled with high performance liquid chromatography-time of flight tandem mass spectrometry (TOF-MS/MS). By utilizing this strategy, we successfully identified four ß2-AR-targeting compounds: tetrahydroberberine, tetrahydrocolumbamine, fumarine and corydaline from Corydalis Rhizome. The association constants between ß2-AR and tetrahydroberberine (9.04 × 104/M) as well as fumarine (4.30 × 104/M) were determined by frontal chromatography. We also found that these two compounds shared the identical binding site on immobilized ß2-AR with corresponding concentrations of 6.67 × 10-4 M and 5.88 × 10-4 M, respectively. The newly established method represents an efficient tool to identify the target specific natural compounds.

Epinephrine-modified methacrylate monolithic column with fumed silica nanoparticle for pressurized capillary electrochromatography.

Via the ring-opening reaction of epoxy groups with epinephrine, a novel epinephrine functionalized polymethacrylate monolith with fumed silica nanoparticles has been fabricated for pressurized capillary electrochromatography. The preparation of epinephrine-modified monoliths has been optimized. In addition, morphology, electroosmotic flow, separation mechanism and column performance have been studied. The internal structure of the monolithic stationary phase was more uniform and the column efficiency increased after the incorporation of nanoparticles. With this column, satisfactory separation capability of aromatic compounds and alkaloids has been achieved and the column efficiency for naphthalene reached 138 696 plates/m. As for the real sample, 3 alkaloids were separated in Huanglian Shangqing capsules, a Chinese traditional medicine.

Intracellular Accumulation as an Indicator of Cytotoxicity to Screen Hepatotoxic Components of Chelidonium majus L. by LC-MS/MS.

A novel strategy was developed to identify hepatotoxic compounds in traditional Chinese medicines (TCMs). It is based on the exposure of HL-7702 cells to a TCM extract, followed by the identification and further determination of potential hepatotoxic compounds accumulated in the cells by liquid chromatography-tandem mass spectrometry (LC-MS/MS). As a case study, potential hepatotoxic components in Chelidonium majus L. were screened out. Five alkaloids (sanguinarine, coptisine, chelerythrine, protopine, and chelidonine) were identified by LC-MS/MS within 10 min, and their intracellular concentrations were first simultaneously measured by LC-MS/MS with a run time of 4 min. A cell viability assay was performed to assess the cytotoxicity of each alkaloid. With their higher intracellular concentrations, sanguinarine, coptisine, and chelerythrine were identified as the main hepatotoxic constituents in Ch. majus. The study provides a powerful tool for the fast prediction of cytotoxic components in complex natural mixtures on a high-throughput basis.

Size-tunable Au@Ag nanoparticles for colorimetric and SERS dual-mode sensing of palmatine in traditional Chinese medicine.

Palmatine is a protoberberine alkaloid separated from several plants and application as an anti-inflammatory and antibacterial agent in the therapy of gastrointestinal and genitourinary disorder. Thus, the fast quantification of palmatine is important in clinic medical assays. Herein, we report simple, fast and sensitive colorimetric visualization and surface-enhanced Raman spectroscopy (SERS) dual-mode detection of palmatine basing on bimetallic size tunable silver shell capped gold nanoparticles (Au@Ag NPs). Interesting, the best signals output for dual-mode sensing of palmatine were both 5 nm Ag shell thickness of Au@Ag NPs. Meanwhile, we found that the addition of NaHSO4 significantly improves the aggregating sensitivity of Au@Ag NPs to trace palmatine. Upon exposure to 0.1 µM level palmatine, NaHSO4-optimized Au@Ag NPs solution exhibits a highly sensitive color change from orange to green and rapid aggregation kinetics within the initial 5 min, which can directly be seen with the naked eye and monitored by UV-vis absorbance spectra. In addition, we measured palmatine by SERS with the excellent enhancement effect of Au@Ag NPs for further increase the sensitivity and selectivity. More importantly, other protoberberine alkaloids do not interfere with this dual-mode sensor due to the different interaction force between Au@Ag NPs and these alkaloids, and the applicability of the sensor is well demonstrated in real samples with satisfactory results. This provide a fast and simple assay for the rapid detection of palmatine in traditional Chinese medicine, the limit of detection (LOD) is 0.13 µM by the naked eye and 0.10 µM by UV-vis spectroscopy. Therefore, the size-tunable of NaHSO4-optimized Au@Ag NPs can be used not only as a naked-eye sensor of palmatine, but also as a highly selective SERS probe.

Rapid identification of "mad honey" from Tripterygium wilfordii Hook. f. and Macleaya cordata (Willd) R. Br using UHPLC/Q-TOF-MS.

Cases of honey poisoning have been reported widely, meaning there is a need for methods that detect "mad honey" or honey contaminated with plant-derived toxins to protect human health. In this study, we compared whole flower extracts and honey from Tripterygium wilfordii Hook. f. (TwHf) and Macleaya cordata (Willd) R. Br (McRB) using QuEChERS (quick, easy, cheap, effective, rugged, and safe) and ultra-high-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UHPLC/Q-TOF-MS). The results revealed several compounds common to whole flowers and honey samples. Triptolide and protopine were selected as potential markers for identifying "mad honeys" from these plants. The developed method can easily detect different honey varieties that were spiked with 5% TwHf and McRB honey samples. Additionally, 90 commercial honey samples were analyzed and determined as free from contamination. The method described in this report could be useful for studies on honey from other poisonous nectar and pollen plants.

Simultaneous Determination of Eight Active Compounds in Baitouweng Decotion and its Single Herbs.

Baitouweng Decotion (BD) is a famous traditional Chinese medicinal prescription, which is composed of Pulsatilla chinensis (bunge) regel, Coptis chinensis franch., Phellodendron chinense and Cortex Fraxini. In this study, a simple and sensitive high performance liquid chromatography coupled with ultraviolet detection method was established for the simultaneous determination of eight marker compounds including Esculin, Fraxin, Esculetin, Fraxetin, Columbamine, Coptisine, Palmatine Chloride and Berberine hydrochloride in BD, the single herbs and their negative controls. The chromatographic separation was performed using an Agilent Eclipse XDB-C18 column with a gradient elution system of acetonitrile and 0.1% phosphoric acid (contained 0.2% triethylamine) solution at a flow rate of 0.8 mL/min. The results demonstrated that the validated method was simple, reliable and successfully applied to evaluate the selected compounds in water extraction (BDW) and ethanol extraction (BDE) of BD, the single herbs and their negative control for quality control. Moreover, the experimental data showed that the contents of the major active components detected in BDE were significantly higher than those in the BDW, while the BDW had several peaks BDE without. The paper also suggested a method to extract Fraxin, Esculin, Fraxetin, Esculetin and Berberine from Baitouweng Decotion more effectively.

A review on analytical methods for natural berberine alkaloids.

Berberine alkaloids, a group of protoberberine alkaloids under the classification of isoquinoline alkaloids, include berberine, coptisine, palmatine, columbamine, dehydrocorydaline, jatrorrhizine, and epiberberine from natural sources. Studies have shown that berberine alkaloids have various pharmacological functions, such as antibacterial, antiviral, blood pressure-lowering, hypoglycaemic, antiarrhythmia, and anticancer effects. Therefore, it is worthwhile to develop analytical methods to investigate the pharmacokinetics and activity mechanisms of berberine alkaloids and to study berberine alkaloids more comprehensively. Current analytical methods for berberine alkaloids include liquid chromatography, thin-layer chromatography, ultraviolet spectroscopy, capillary electrophoresis, and gas chromatography. The most widely used detection method is mass spectrometry. In order to provide a systematic and comprehensive summary and to serve as a reference for the future pharmacokinetics studies and analysis of berberine alkaloids, analytical methods for natural berberine alkaloids that have been used in the past ten years are reviewed here.