Concentrations Of Baicalin Research Articles

Differentiated hypoglycemic effects of baicalin, berberine and puerarin on insulin-resistance HepG2 cells

To investigate the hypoglycemic effects of baicalin, berberine, puerarin and liquiritin on the insulin resistance (IR) cells. The IR model of HepG2 cells was established by treatment with insulin and dexamethasone for 48 h. Glucose uptake, glycogen content and cell viability were detected with different concentrations of baicalin, berberine, puerarin, liquiritin in IR-HepG2 cells. Compared with IR model group, all of intervened groups significantly increased the glucose consumption, except for liquiritin groups and 1 μmol·L⁻¹ baicalin group. Moreover, 10, 20, 50 μmol·L⁻¹ baicalin, 5, 10, 20, 50 μmol·L⁻¹ berberine and 40, 80, 160 μmol·L⁻¹ puerarin significantly elevated glycogen content in IR-HepG2 cells. Liquiritin did not show obvious hypoglycemic effect. Compared with normal group, the mRNA expression levels of GLUT1 and GLUT4 were decreased in IR-HepG2 cells according to qPCR results. 5, 20 μmol·L⁻¹ berberine decreased the mRNA expression level of GLUT1 in IR-HepG2 cells, whereas 20, 40, 80 μmol·L⁻¹ puerarin significantly elevated the mRNA expression level of GLUT1. Moreover, 10, 20, 50 μmol·L⁻¹ baicalin and 20 μmol·L⁻¹ berberine increased the mRNA expression level of GLUT4. Whereas, 40, 80 μmol·L⁻¹ puerarin decreased the mRNA expression level of GLUT4. Western blot results suggested that 10, 20, 50 μmol·L⁻¹ baicalin significantly increased the protein expressions of GLUT2 and GLUT4, whereas 20, 40, 80 μmol·L⁻¹ puerarin significantly up-regulated GLUT1 and GLUT2 proteins. In addition, 20 μmol·L⁻¹ berberine increased the protein expressions of GLUT2 and GLUT4, whereas 10 μmol·L⁻¹ berberine up-regulated GLUT4 expression. The results preliminarily suggested that baicalin, berberine and puerarin have differentiated hypoglycemic effects, which accelerate glucose transport, increase glycogen synthesis, regulate glucose metabolism and improve hepatic IR.

English

Scutellaria or skullcap is a genus containing approximately 350 species of flowering plants, many of which are sold and marketed for their medicinal value. Flavonoids found in Scutellaria spp. have demonstrated anti-inflammatory, antiviral, sedative, antithrombotic and antioxidant affects. Baicalin, a flavonoid produced by Scutellaria spp., is an important compound used to treat anxiety. Scutellaria spp. have potential as commercially valuable specialty crops based on their visual and medicinal properties; however, a lack of commercial production techniques for successful cultivation of this genus precludes adoption by most growers. The influence of plant production techniques on flowering and baicalin synthesis is undocumented; thus, empirical research is needed for development of commercial production protocol. Objectives of this research were to investigate the effect of nutrient application rate and plant available water on growth and baicalin synthesis in Scutellaria arenicola and Scutellaria integrifolia, two common species of Scutellaria found in eastern United States. To accomplish these objectives, S. arenicola and S. integrifolia were cultivated in a greenhouse and subjected to one out of four nutrient application rates and one out of two volumetric water content rates. Results demonstrated that synthesis of baicalin, the main flavonoid of the Scutellaria genus that contributes to its reported medicinal benefits, occurred in both species. Fertilization rate and volumetric water content were found to influence both plant growth and baicalin concentration in S. integrifolia. In contrast to results observed for S. integrifolia, volumetric soil water and nutrient application rate did not influence plant growth in S. arenicola. Scutellaria spp. cultivated in the greenhouse had similar concentrations of baicalin to those harvested from the wild, undisturbed natural habitats. Results from this investigation will assist in development of commercial production protocol for these species and provides the first foundational research that has reported the presence of baicalin, a high value medicinal compound in S. arenicola. Key words: Skullcap, medicinal, flavonoid, cultivation, production.

Baicalin administration attenuates hyperglycemia-induced malformation of cardiovascular system

In this study, the effects of Baicalin on the hyperglycemia-induced cardiovascular malformation during embryo development were investigated. Using early chick embryos, an optimal concentration of Baicalin (6 μM) was identified which could prevent hyperglycemia-induced cardiovascular malformation of embryos. Hyperglycemia-enhanced cell apoptosis was reduced in embryos and HUVECs in the presence of Baicalin. Hyperglycemia-induced excessive ROS production was inhibited when Baicalin was administered. Analyses of SOD, GSH-Px, MQAE and GABAA suggested Baicalin plays an antioxidant role in chick embryos possibly through suppression of outwardly rectifying Cl(−) in the high-glucose microenvironment. In addition, hyperglycemia-enhanced autophagy fell in the presence of Baicalin, through affecting the ubiquitin of p62 and accelerating autophagy flux. Both Baicalin and Vitamin C could decrease apoptosis, but CQ did not, suggesting autophagy to be a protective function on the cell survival. In mice, Baicalin reduced the elevated blood glucose level caused by streptozotocin (STZ). Taken together, these data suggest that hyperglycemia-induced embryonic cardiovascular malformation can be attenuated by Baicalin administration through suppressing the excessive production of ROS and autophagy. Baicalin could be a potential candidate drug for women suffering from gestational diabetes mellitus.

Baicalin inhibits Escherichia coli isolates in bovine mastitic milk and reduces antimicrobial resistance

In this study, we aimed to evaluate the inhibitory effect of baicalin on Escherichia coli in vitro and the effects of baicalin treatment on antimicrobial resistance of the E. coli isolates. Through isolation, purification, and identification, a total of 56 E. coli strains were isolated from 341 mastitic milk samples. The study of inhibition effect of baicalin on the E. coli strains in vitro was focused on permeability and morphology of the isolates using an alkaline phosphatase kit and scanning electron microscopy. Furthermore, the resistance spectrum of the isolates to the common antimicrobial agents was tested at sub-minimum inhibitory concentrations of baicalin by the agar dilution method. Extended-spectrum β-lactamase and plasmid-mediated quinolone resistance genes were amplified by PCR before and after incubation with baicalin. The results revealed that baicalin has certain inhibitory effects on the isolates in vitro. The alkaline phosphatase enzyme activity was significantly increased from 1.246 to 2.377 U/100 mL, and the surface of E. coli was concave and shriveled. Analysis of the resistance spectrum and PCR amplification showed that, after administration with baicalin, the sensitivity of most strains to the selected antimicrobial agents was enhanced. Strikingly, the drug-resistant genes from 71.43% (40/56) of these isolates were found to have drug-resistant genes to different extents. Altogether, the current study confirmed both the inhibitory effect on Escherichia coli in vitro and the reduction of antimicrobial resistance by baicalin. This is the first comprehensive study to report on baicalin, a traditional Chinese medicine that acts on E. coli isolated from the mastitic milk samples.

The Influence of Compatibility of Rhubarb and Radix Scutellariae on the Pharmacokinetics of Anthraquinones and Flavonoids in Rat Plasma.

Rhubarb-Radix scutellariae is a classic herb pair, which is commonly used to clear away heat and toxin in clinic. The aim of this study was to investigate the influence of compatibility of Rhubarb and Radix scutellariae on the pharmacokinetic behaviors of anthraquinones and flavonoids in rat plasma. Eighteen rats were randomly divided into three groups, and were orally administered Rhubarb and/or Radix scutellariae extracts. A sensitive and rapid UPLC-MS/MS method was developed and validated to determine the concentrations of baicalin, baicalein, wogonside, wogonin, rhein, and emodin in rat plasma. The concentrations of phase II conjugates of flavonoid aglycones and anthraquinone aglycones were also determined after hydrolyzing the plasma with sulfatase. Compared with administration of Radix scutellariae alone, co-administration of Rhubarb significantly decreased the first maximum plasma concentration (C max1) of baicalin, wogonside, and the phase II conjugates of baicalein, wogonin to 46.40, 61.27, 41.49, and 20.50%, respectively. The area under the plasma concentration-time curve from time zero to infinity (AUC0-∞) was significantly decreased from 82.60±20.22 to 51.91±7.46μM·h for rhein and 276.83±98.02 to 175.42±86.82μM·h for the phase II conjugates of wogonin after compatibility. The time to reach the first maximum plasma concentration (T max1) of anthraquinones was shortened and the second peak of anthraquinones disappeared after compatibility. Compatibility of Rhubarb and Radix scutellariae can significantly affect the pharmacokinetic behaviors of characteristic constituents of the two herbs. The cause of these pharmacokinetic differences was further discussed combined with the in vivo ADME (absorption, disposition, metabolism, and excretion) processes of anthraquinones and flavonoids.

Baicalin induces apoptosis in human osteosarcoma cell through ROS-mediated mitochondrial pathway

Baicalin is extracted from a traditional Chinese herb, Scutellaria baicalensis. In this study, the anticancer activity and underlying mechanisms of baicalin towards human osteosarcoma cell (HOS) were investigated. Baicalin could inhibit HOS cell proliferation in a concentration-dependent manner. Mitochondrial membrane potential decreased obviously after treated with different concentration of baicalin by flow cytometry assay and revealed that baicalin triggered a significant generation of reactive oxygen species (ROS). Western blotting assay further revealed that baicalin-induced cell apoptosis by suppressing Bcl-2 level, then activating caspase-9 and caspase-3. In vivo experiment, baicalin significantly suppressed tumour growth in female BALB/C nude mice bearing HOS tumours. In addition, baicalin did show toxicity to treated animal by comparing the body weight increase and mortality. In general, the present results demonstrated that baicalin-induced apoptosis in human osteosarcoma cell via a ROS-mediated mitochondrial pathway. The paper indicated that baicalin is a promising candidate for the treatment of HOS.

An integrated strategy by using target tissue metabolomics biomarkers as pharmacodynamic surrogate indices to screen antipyretic components of Qingkaikling injection

Traditional Chinese medicine (TCM) treatment can be valuable therapeutic strategies. However, the active components and action mechanisms that account for its therapeutic effects remain elusive. Based on the hypothesis that the components of a formula which exert effect would be measurable in target tissue, a target tissue metabolomics-based strategy was proposed for screening of antipyretic components in Qingkaikling injection (QKLI). First, we detected the components of QKLI which could reach its target tissue (hypothalamus) by determining the hypothalamus microdialysate and discovered that only baicalin and geniposide could be detected. Then, by conducting hypothalamus metabolomics studies, 14 metabolites were screened as the potential biomarkers that related to the antipyretic mechanisms of QKLI and were used as its pharmacodynamic surrogate indices. Subsequently, the dynamic concentration of baicalin and geniposide in hypothalamus microdialysates and biomarkers in hypothalamus were measured and correlated with each other. The results indicated that only baicalin shown a good correlation with these biomarkers. Finally, a network pharmacology approach was established to validate the antipyretic activity of baicalin and the results elucidated its antipyretic mechanisms as well. The integrated strategy proposed here provided a powerful means for identifying active components and mechanisms contributing to pharmacological effects of TCM.

Analysis on microdialysis probe recovery of baicalin in vitro and in vivo based on LC-MS/MS

To further study the brain behavior and the pharmacokinetics of baicalin in intercellular fluid of brain, and study the recovery rate and stability of brain and blood microdialysis probe of baicalin in vitro and in vivo. The concentration of baicalin in brain and blood microdialysates was determined by LC-MS/MS and the probe recovery for baicalin was calculated. The effects of different flow rates (0.50, 1.0, 1.5, 2.0，3.0 μL•min⁻¹) on recovery in vitro were determined by incremental method and decrement method. The effects of different drug concentrations (50.00, 200.0, 500.0, 1 000 μg•L⁻¹) and using times (0, 1, 2) on recovery in vitro were determined by incremental method. The probe recovery stability and effect of flow rate on recovery in vivo were determined by decrement method, and its results were compared with those in in vitro trial. The in vitro recovery of brain and blood probe of baicalin was decreased with the increase of flow rate under the same concentration; and at the same flow rate, different concentrations of baicalin had little influence on the recovery. The probe which had been used for 2 times showed no obvious change in probe recovery by syringe with 2% heparin sodium and ultrapure water successively. In vitro recovery rates obtained by incremental method and decrement method were approximately equal under the same condition, and the in vivo recovery determined by decrement method was similar with the in vitro results and they were showed a good stability within 10 h. The results showed that decrement method can be used for pharmacokinetic study of baicalin, and can be used to study probe recovery in vivo at the same time.

Baicalin promotes the viability of Schwann cells in vitro by regulating neurotrophic factors.

The proliferation and migration of Schwann cells (SCs) are key events in the process of peripheral nerve repair. This is required to promote the growth of SCs and is a challenge during the treatment of peripheral nerve injury. Baicalin is a natural herb-derived flavonoid compound, which has been reported to possess neuroprotective effects on rats with permanent brain ischemia and neuronal differentiation of neural stem cells. The association of baicalin with neuroprotection leads to the suggestion that baicalin may exert effects on the growth of SCs. In the present study, the effects of baicalin on SCs of RSC96 were investigated. RSC96 SCs were treated with various concentrations of baicalin (0, 5, 10 or 20 µM) for 2, 4 and 6 days. Cell attachment, viability and gene expression were monitored via the MTT assay and reverse transcription-quantitative polymerase chain reaction. The gene expression levels of several neurotrophic factors, such as glial cell-derived neurotrophic factor, brain-derived neurotrophic factor and ciliary neurotrophic factor, which are considered important factors in the process of never cell regeneration, were detected. The results indicated that baicalin was able to promote the viability of RSC96 SCs in a dose-dependent manner and the concentration of 20 µM of baicalin exhibited the greatest cell viability and gene expression of the studied neurotrophic factors. The present findings suggested that baicalin likely affects SCs metabolism, through modulating the expression of neurotrophic factors. To conclude, the present study indicates that baicalin may be potential therapeutic agent for treating peripheral nerve regeneration.

Protective effects of baicalin on rabbit articular chondrocytes in vitro.

Drug therapy is one of the typical treatments for post-injury inflammation of cartilage. Traditional Chinese herbs have potential as treatments, as their long history of clinical application has demonstrated they are effective and induce minimal side effects. Baicalin is a traditional Chinese medicine that has been used to treat inflammation, fever, ulcers and cancer for hundreds of years. Previous studies have demonstrated that baicalin may decrease levels of interleukin-1β and suppress the expression of type-I collagen, thus attenuating cartilage degeneration. In the present study, the effect of baicalin on chondrocytes was assessed by examining the morphology, proliferation, extracellular matrix (ECM) synthesis and cartilage-specific gene expression of chondrocytes. The results indicated that baicalin may promote the proliferation of articular chondrocytes, secretion of cartilage ECM and collagen type II, aggrecan and SRY box (Sox) 9 gene upregulation. The expression of collagen I, a marker of chondrocyte dedifferentiation, was downregulated by baicalin; therefore, baicalin may maintain the phenotype of chondrocytes. Within the recommended concentrations of baicalin ranging from 0.625–6.25 µmol/l cell proliferation was increased and a 1.25 µmol/l dose of baicalin exerted the most positive effect on articular chondrocytes. The results of the present study may therefore indicate that baicalin may be used as a novel agent promoting the repair of articular cartilage damage.

Baicalin promotes the bacteriostatic activity of lysozyme on S. aureus in mammary glands and neutrophilic granulocytes in mice.

Staphylococcus aureus causes mastitis as a result of community-acquired or nosocomial infections. Lysozyme (LYSO) is an enzyme that is upregulated in many organisms during the innate immune response against infection by bacterial pathogens. Baicalin is a bioactive flavonoid that can bind to enzymes, often to potentiate their effect. Here we tested the effects of baicalin on the activity of LYSO using the S. aureus mastitis mouse model and neutrophilic granulocyte model of S. aureus infection. In our experiments, S. aureus counts decreased with increasing baicalin concentration. Furthermore, qPCR and western blot analyses showed that LYSO expression was unaffected by baicalin, while fluorescence quenching and UV fluorescence spectral analyses showed that baicalin binds to LYSO. To test whether this binding increased LYSO activity, we assessed LYSO-induced bacteriostasis in the presence of baicalin. Our results showed that LYSO-induced S. aureus bacteriostasis increased with increasing concentrations of baicalin, and that baicalin binding to LYSO synergistically increased the antibacterial activity of LYSO. These results demonstrate that baicalin enhances LYSO-induced bacteriostasis during the innate immune response to S. aureus. They suggest baicalin is a potentially useful therapeutic agent for the treatment of bacterial infections.

Green synthesized Co nanoparticles doped amino-graphene modified electrode and its application towards determination of baicalin

The present paper reported an one-pot synthesis of Co nanoparticles doped amino-graphene nanocomposites (Co-amino-Gr), involving in situ generation of Co nanoparticles (NPs). The simultaneous reduction of graphene oxide (GO) and Co2+ to produce Co-amino-Gr had been achieved under mild reaction conditions using an environmentally benign reducing agent, glycine. By combining the merits of amino-Gr and the Co NPs, a highly sensitive electrochemical sensor was erected to detect baicalin based on the Co-amino-Gr nanocomposites. Under optimum conditions, the response peak currents were linear related with baicalin concentrations in the range of 1.0×10−8–8.0×10−7molL−1 with a lower detection limit of 5.0×10−9molL−1 (S/N=3). Additionally, the proposed method was used to detect baicalin in the medicinal capsules with satisfactory results.

Molecular characterization of flavonoid biosynthetic genes and accumulation of baicalin, baicalein, and wogonin in plant and hairy root of Scutellaria lateriflora.

Scutellaria lateriflora is well known for its medical applications because of the presence of flavanoids and alkaloids. The present study aimed to explore the molecular aspects and regulations of flavanoids. Five partial cDNAs encoding genes that are involved in the flavonoid biosynthetic pathway: phenylalanine ammonia lyase (SlPAL), cinnamate 4-hydroxylase (SlC4H), 4-coumaroyl CoA ligase (Sl4CL), chalcone synthase (SlCHS), and chalcone isomerase (SlCHI) were isolated from S. lateriflora. Organ expression analysis showed that these genes were expressed in all organs analyzed with the highest levels correlating with the richest accumulation of wogonin in the roots. Baicalin and baicalein differentially accumulated in S. lateriflora plants, with the highest concentration of baicalin and baicalein detected in the leaves and stems, respectively. Exogenous methyl jasmonate (MeJA) significantly enhanced the expression of SlCHS and SlCHI, and accumulation of baicalin (22.54 mg/g), baicalein (1.24 mg/g), and wogonin (5.39 mg/g) in S. lateriflora hairy roots. In addition, maximum production of baicalin, baicalein, and wogonin in hairy roots treated with MeJA was approximately 7.44-, 2.38-, and 2.12-fold, respectively. Light condition increased the expression level of SlCHS, the first committed step in flavonoid biosynthesis in hairy roots of S. lateriflora after 3 and 4 weeks of development compared to the dark condition. Dark-grown hairy roots contained a higher content of baicalin and baicalein than light-grown hairy roots, while light-grown hairy roots accumulated more wogonin than dark-grown hairy roots. These results may helpful for the metabolic engineering of flavonoids biosynthesis in S. lateriflora.

Inhibition of skin inflammation by baicalin ultradeformable vesicles

The topical efficacy of baicalin, a natural flavonoid isolated from Scutellaria baicalensis Georgi, which has several beneficial properties, such as antioxidative, antiviral, anti-inflammatory and antiproliferative, is hindered by its poor aqueous solubility and low skin permeability. Therefore, its incorporation into appropriate phospholipid vesicles could be a useful tool to improve its local activity. To this purpose, baicalin at increasing concentrations up to saturation, was incorporated in ultradeformable vesicles, which were small in size (⿼67nm), monodispersed (PI<0.19) and biocompatible, regardless of the concentration of baicalin, as confirmed by in vitro studies using fibroblasts. On the other hand, transdermal flux through human epidermis was concentration dependent. The in vivo results showed the significant anti-inflammatory activity of baicalin loaded nanovesicles irrespective of the concentration used, as they were able to reduce the skin damage induced by the phorbol ester (TPA) application, even in comparison with dexamethasone, a synthetic drug with anti-inflammatory properties. Overall results indicate that ultradeformable vesicles are promising nanosystems for the improvement of cutaneous delivery of baicalin in the treatment of skin inflammation.

Electrochemical behavior and determination of baicalin on a glassy carbon electrode modified with molybdenum disulfide nano-sheets

In this study, a molybdenum disulfide (MoS2) nano-sheets-modified glassy carbon electrode (GCE) was prepared, and the electrochemical behavior of baicalin on the proposed electrode was investigated by cyclic voltammetry (CV) in PBS buffer solution (pH7.0). The experimental results showed that baicalin exhibits enhanced voltammetric response on the MoS2-modified GCE. Based on the enhanced voltammetric response of baicalin on the MoS2-modified GCE, a sensitive and selective electrochemical method for the determination of baicalin was developed by using differential pulse voltammetry (DPV). Various experimental parameters including the pH of supporting electrolyte, amount of MoS2 nano-sheets and accumulation time were optimized. Under the optimized conditions, the oxidation peak current was linearly proportional to the baicalin concentrations in the range of 1.25×10−7M–1.25×10−5M, and the detection limit (S/N=3) was calculated to be 5.0×10−8M. The developed method was successfully used to detect baicalin in pharmaceutical samples with a recovery of 97–109% and a relative standard deviation (RSD, n=6)<6%.

Mechanism of baicalin compatibility in chinese medicine formula Banxia Xiexin Decoction () by pharmacokinetics and indirect competitive enzyme-linked immunosorbent assays in mice.

To determine the effects of different formulations of Banxia Xiexin Decoction ( , BXD) on the pharmacokinetics of baicalin (BAL) in mice. Pungent, bitter, and sweet components of BXD (totaling 7 Chinese herbs) were formulated into the following groups: K (bitter herbs), XK (pungent and bitter herbs), KG (bitter and sweet herbs), and BXD (all 7 herbs) groups. These different formulations were administered intragastrically in mice, and blood was collected via the tail vein for continuous monitoring. BAL, which is a main active constituent in Scutellaria baicalensis Georgi., was detected in this study. Indirect competitive enzyme-linked immunosorbent assays (icELISAs) based on anti-BAL-monoclonal antibodies were employed to determine BAL concentrations in each group. The concentrations of BAL in blood samples from mice in the K and XK groups were lower than those in other groups. In all groups, BAL concentrations peaked at around 1-1.5 h and again at 5-7 h. There were no significant differences in the timing of peak BAL concentrations between groups. However, the peak concentrations and area under curve (AUC)0-36 h in the KG and BXD groups were almost 3 times of those in the K and XK groups. Differing compatibilities of BXD caused dissimilar pharmacokinetics of BAL. Moreover, we demonstrated a method for the continuous detection of blood concentrations of Chinese medicines in mice, and icELISA may be a feasible technique for the study of pharmcokinetic mechanisms of Chinese medicine.

Shade, Irrigation, and Nutrients Affect Flavonoid Concentration and Yield in American Skullcap

American skullcap (Scutellaria lateriflora L.) is valued for its sedative properties that are associated with flavonoids. Information on how growing conditions affect flavonoid content is lacking. A 2 by 2 by 3 factorial experiment was conducted in a randomized complete block design (r = 4) with a split‐plot restriction on randomization to explore effects of light, irrigation, and nutrient application on flavonoid concentration and yield in American skullcap. Treatment factors were shade (40% shade vs. no shade), irrigation (applied at 30 kPa vs. no irrigation), and nutrients (no fertilizer vs. fertilizer [100 kg N, 68 kg P, 42 kg K ha−1] or chicken litter [100 kg N, 50 kg P, 123 kg K ha−1]). Shade formed the main plot units; irrigation and nutrients were randomized within subplots. Aboveground biomass was harvested twice in both 2007 and 2008. Dried, finely ground samples were extracted and analyzed for flavonoid concentration using high‐performance liquid chromatography (HPLC). The flavonoid baicalin was present in highest concentration and yield, followed by baicalein; wogonin and chrysin were present in only small amounts. Flavonoid concentration was 72% higher in full sun, 15% higher with irrigation, while added nutrients decreased baicalin concentration by 6% but increased baicalein by 16%. Significant interactions of shade × irrigation and shade × nutrients were also observed. Flavonoid yield was 25% higher under shade, 92% higher with irrigation, and 43% higher with added nutrients. Significant interactions of shade × irrigation, shade × nutrients, and irrigation × nutrients were also observed. Increasing biomass yield had a greater effect on total flavonoid harvested than did increasing flavonoid concentration.

Anti-NDV activity of baicalin from a traditional Chinese medicine in vitro.

The purpose of this study was to investigate the anti-Newcastle disease virus (NDV) activities of baicalin from Scutellaria baicalensis, a Traditional Chinese Medicine in vitro. Chicken embryo fibroblasts (CEFs) were infected with NDV, and quantitative analysis of apoptotic cells was performed using flow cytometry. Cytotoxicity and anti-viral activities of baicalin were studied using the MTT method. The results showed that the maximal safe concentrations of baicalin to CEFs was 1 × 2−2 mg/ml. Baicalin could directly kill NDV, inhibit the infectivity of NDV to CEF and block intracellular NDV. It inhibited the apoptosis of NDV-infected CEFs and suppressed the spread of NDV. These results indicate that baicalin has strong anti-NDV activity and has the potential for use as components of an antiviral drug.

Highly selective enrichment of baicalin in rat plasma by boronic acid-functionalized core–shell magnetic microspheres: Validation and application to a pharmacokinetic study

To the best of our knowledge, this study is the first to successfully apply a novel, highly selective enrichment technique based on boronic acid-functionalized core–shell magnetic microspheres (BA-Fe3O4@SiO2–Au@mSiO2) with a large surface area and uniform pore size, to determine the baicalin concentration in rat plasma by HPLC. By taking advantage of the special interaction between boronic acid and baicalin under alkaline conditions, as well as the microspheres' size exclusion ability, baicalin was selectively extracted from protein-rich biosamples, such as plasma, without any other pretreatment procedure except for a 10-min vortexing step. BA-Fe3O4@SiO2–Au@mSiO2 microsphere-adsorbed baicalin was straightforwardly and rapidly isolated from the matrix using a magnet. Baicalin was subsequently eluted from the microspheres under acidic conditions for 2min for further HPLC analysis. The extraction conditions, such as the amount of microspheres added, adsorption time, adsorption pH, and elution time and pH, were also determined. Furthermore, method validation, including the linear range, detection limit, precision, accuracy, and recovery, were determined. This newly developed method based on BA-Fe3O4@SiO2–Au@mSiO2 microspheres is a simple, accurate, selective, and green analytical preparatory technique for analyzing baicalin in rat plasma. This study will be further novel research on the analysis of complex plasma samples and the pharmacokinetics of drugs similar to baicalin.

An Ultra-Performance Liquid Chromatography Photodiode Array Detection Tandem Mass Spectrometric Method for Simultaneous Determination of Seven Major Bioactive Constituents in Xiaochaihutang and Its Application to Fourteen Compatibilities Study.

A rapid and sensitive ultra-performance liquid chromatography photodiode array detection tandem mass spectrometric method (UPLC-PDA-MS-MS) was developed and validated to simultaneously determine seven major bioactive constituents in the formula of traditional Chinese medicines Xiaochaihutang (XCHT). To investigate the discipline of compatibility in XCHT, 14 kinds of compatibilities designed by orthogonal array were also analyzed. The separation was performed on an ACQUITY UPLC™ BEH C18 column (100 × 2.1 mm, 1.7 µm) using gradient elution with a mobile phase of 0.1% formic acid and acetonitrile at a flow rate of 0.2 mL/min. Two detection techniques of PDA detector and MS-MS detector were proposed, respectively. The concentrations of baicalin and wogonoside were high enough for PDA detection while low-concentration bioactive constituents including saikosaponin a, ginsenoside Rg1, liquiritin, baicalein and wogonin were quantified by MS-MS detection. The proposed method was fully validated in terms of sensitivity, linearity, specificity, precision, repeatability and recovery. This is the first report on the simultaneous determination of the major bioactive constituents of XCHT by UPLC-PDA-MS-MS, which could be used to evaluate the quality of XCHT and to investigate the discipline of compatibility in XCHT.