Antimutagenic and antiradical properties of flavones from the roots of Scutellaria baicalensis georgi

Baicalin and lung diseases

Studies focusing on natural products have been conducted worldwide, and the results suggest that their natural ingredients effectively treat a wide range of illnesses. Baicalin (BIA) is a glycoside derived from the flavonoid baicalein present in Scutellaria baicalensis of the Lamiaceae family. Interestingly, BIA has been shown to protect the lungs in several animal models used in numerous studies. Therefore, we fully analyzed the data of the studies that focused on BIA's lung protective function against various injuries and included them in this review. Interestingly, BIA exhibits promising effects against acute lung injury, lung fibrosis, pulmonary embolism, and lung remodelling associated with COPD, LPS, and paraquat insecticide. BAI exhibits anticancer activity against lung cancer. Additionally, BIA potently attenuates lung damage associated with infections. BIA primarily exerts its therapeutic effects by suppressing inflammation, oxidative stress immune response, and apoptosis pathways. Nrf2/HO-1, PI3K/Akt, NF-κB, STAT3, MAPKs, TLR4, and NLRP3 are important targets in the pulmonary therapeutic effects of BIA on different lung disease models. Consequently, we recommend using it in future potential clinical applications, its contribution to treatment guidelines, and translating its promising effects to clinical practice in lung diseases.

Modulation of the Dipole Potential of Model Lipid Membranes with Phytochemicals: Molecular Mechanisms, Structure-Activity Relationships, and Implications in Reconstituted Ion Channels

Phytochemicals, such as flavonoids, stilbenoids, alkaloids, terpenoids, and related compounds, have a wide range of useful pharmacological properties which cannot be ascribed to binding to a single peptide or protein target alone. Due to the relatively high lipophilicity of phytochemicals, the lipid membrane is thought to mediate their effects via changes in the properties of the lipid matrix, in particular, by modulating the transmembrane distribution of the electrical potential and, consequently, the formation and functioning of the ion channels reconstituted in the lipid bilayers. Therefore, biophysical studies on the interactions between plant metabolites and model lipid membranes are still of interest. This review represents an attempt to provide a critical analysis of a variety of studies on altering membranes and ion channels with phytochemicals via disturbing the potential drop at the membrane-aqueous solution interface. Critical structural motifs and functioning groups in the molecules of plant polyphenols (alkaloids and saponins are identified) and the possible mechanisms of dipole potential modulation with phytochemicals are discussed.

Adsorption and Purification of Baicalin from Scutellaria baicalensis Georgi Extract by Ionic Liquids (ILs) Grafted Silica

Baicalin which has multiple biological activities is the main active component of the root of Scutellaria baicalensis Georgi (SBG). Although its isolation and purification by adsorption methods have aroused much interest of the scientific community, it suffered from the poor selectivity of the adsorbents. In this work, an environmentally benign method was developed to prepare ionic liquids (ILs) grafted silica by using IL 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([C₄mim]NTf₂) and ethanol as reaction media. The IL 1-propyl-3-methylimidazolium chloride ([C₃mim]Cl) grafted silica ([C₃mim]⁺Cl⁻@SiO₂) was used to adsorb and purify baicalin from the root extract of Scutellaria baicalensis Georgi (SBG). Experimental results indicated that the adsorption equilibrium can be quickly achieved (within 10 min). The adsorption behavior of [C₃mim]⁺Cl⁻@SiO₂ for baicalin was in good agreement with Langmuir and Freundlich models and the adsorption was a physisorption process as suggested by Dubinin–Radushkevich model. Compared with commercial resins, [C₃mim]⁺Cl⁻@SiO₂ showed the strongest adsorption ability and highest selectivity. After desorption and crystallization, a purity of baicalin as high as 96.5% could be obtained. These results indicated that the ILs grafted silica materials were promising adsorbents for the adsorption and purification of baicalin and showed huge potential in the purification of other bioactive compounds from natural sources.

Natural products for the prevention and treatment of cholestasis: A review

Cholestasis is a common manifestation of decreased bile flow in various liver diseases. It results in fibrosis and even cirrhosis without proper treatment. It is believed that a wide range of factors, including transporter dysfunction, oxidative stress, inflammatory damage, and immune disruption, can cause cholestasis. In recent years, natural products have drawn much attention for specific multiple-target activities in diseases. Many attempts have been made to investigate the anticholestatic effects of natural products with advanced technology. This review summarizes recent studies on the biological activities and mechanisms of recognized compounds for cholestasis treatment. Natural products, including various flavonoids, phenols, acids, quinones, saponins, alkaloids, glycosides, and so on, function as comprehensive regulators via ameliorating oxidative stress, inflammation, and apoptosis, restoring bile acid balance with hepatic transporters, and adjusting immune disruption. Moreover, in this progress, nuclear factor erythroid 2-related factor 2, reactive oxygen species production, heme oxygenase-1, NF-κB, cholesterol 7 alpha-hydroxylase, and farnesoid X receptors are thought as main targets for the activity of natural products. Therefore, this review presents the detailed mechanisms that include multiple targets and diverse signalling pathways. Natural products are the valuable when seeking novel therapeutic agents to treat cholestatic liver diseases.

Anticancer Plants: A Review of the Active Phytochemicals, Applications in Animal Models, and Regulatory Aspects

The rising burden of cancer worldwide calls for an alternative treatment solution. Herbal medicine provides a very feasible alternative to western medicine against cancer. This article reviews the selected plant species with active phytochemicals, the animal models used for these studies, and their regulatory aspects. This study is based on a meticulous literature review conducted through the search of relevant keywords in databases, Web of Science, Scopus, PubMed, and Google Scholar. Twenty plants were selected based on defined selection criteria for their potent anticancer compounds. The detailed analysis of the research studies revealed that plants play an indispensable role in fighting different cancers such as breast, stomach, oral, colon, lung, hepatic, cervical, and blood cancer cell lines. The in vitro studies showed cancer cell inhibition through DNA damage and activation of apoptosis-inducing enzymes by the secondary metabolites in the plant extracts. Studies that reported in vivo activities of these plants showed remarkable results in the inhibition of cancer in animal models. Further studies should be performed on exploring more plants, their active compounds, and the mechanism of anticancer actions for use as standard herbal medicine.

Baicalin Ameliorates Experimental Liver Cholestasis in Mice by Modulation of Oxidative Stress, Inflammation, and NRF2 Transcription Factor

Experimental cholestatic liver fibrosis was performed by bile duct ligation (BDL) in mice, and significant liver injury was observed in 15 days. Administration of baicalin in mice significantly ameliorates liver fibrosis. Experimental cholestatic liver fibrosis was associated with induced gene expression of fibrotic markers such as collagen I, fibronectin, alpha smooth muscle actin (SMA), and connective tissue growth factor (CTGF); increased inflammatory cytokines (TNFα, MIP1α, IL1β, and MIP2); increased oxidative stress and reactive oxygen species- (ROS-) inducing enzymes (NOX2 and iNOS); dysfunctional mitochondrial electron chain complexes; and apoptotic/necrotic cell death markers (DNA fragmentation, caspase 3 activity, and PARP activity). Baicalin administration on alternate day reduced fibrosis along with profibrotic gene expression, proinflammatory cytokines, oxidative stress, and cell death whereas improving the function of mitochondrial electron transport chain. We observed baicalin enhanced NRF2 activation by nuclear translocation and induced its target genes HO-1 and GCLM, thus enhancing antioxidant defense. Interplay of oxidative stress/inflammation and NRF2 were key players for baicalin-mediated protection. Stellate cell activation is crucial for initiation of fibrosis. Baicalin alleviated stellate cell activation and modulated TIMP1, SMA, collagen 1, and fibronectin in vitro. This study indicates that baicalin might be beneficial for reducing inflammation and fibrosis in liver injury models.

Influence of Culture Medium Composition and Light Conditions on the Accumulation of Bioactive Compounds in Shoot Cultures of Scutellaria lateriflora L. (American Skullcap) Grown In Vitro

Methanolic extracts from in vitro grown Scutellaria lateriflora shoots cultured on five Murashige and Skoog (MS) medium variants supplemented with different combinations of 6-benzylaminopurine (BAP) and α-naphthaleneacetic acid (NAA) under different light conditions (monochromatic light, white light and no light) were analysed by HPLC for three groups of metabolites: flavonoids (26 compounds), phenolic acids and their precursors (19+2) and phenylethanoid glycosides (2). The analyses revealed the presence of baicalein, baicalin, wogonin, wogonoside, 3,4-dihydroxyphenylacetic acid and verbascoside. There was clear evidence of the influence of plant growth regulators and light conditions on the accumulation of the analysed groups of secondary metabolites. The amounts of the compounds changed within a wide range—for the total flavonoid content, 30.2-fold (max. 1204.3 mg·100 g⁻¹ dry weight (DW)); for 3,4-dihydroxyphenylacetic acid, 5.5-fold (max. 33.56 mg·100 g⁻¹ DW); and for verbascoside, 1.5-fold (169.15 max. mg·100 g⁻¹ DW). The best medium for the production of most of the compounds was the Murashige and Skoog variant with 1 mg l⁻¹ BAP and 1 mg l⁻¹ NAA. For verbascoside, the best ‘productive’ medium was the MS variant supplemented with 0.5 mg l⁻¹ BAP and 2 mg l⁻¹ NAA. The accumulation of the metabolites was stimulated to the greatest extent by blue light, under which the extracts were found to contain the highest total amount of flavonoids and the highest amounts of flavonoid glucuronides, baicalin and wogonoside, as well as of verbascoside. Their amounts were, respectively, 1.54-, 1.49-, 2.05- and 1.86-fold higher than under the control white light.

Experimental Paper. Intrapopulation variability of flavonoid content in roots of Baikal skullcap (Scutellaria baicalensis Georgi)

Introduction: Baikal skullcap (Scutellaria baicalensis Georgi) is an important medicinal plant, indigenous to Asia. Due to a wide range of pharmacological activities, its roots has been used for ages in Traditional Chinese Medicine. Recently, the species has become an object of interest of Western medicine, as well. Objective: The aim of the study was to determine the variability of Baikal skullcap population originated from Mongolia and cultivated in Poland, in terms of content and composition of flavonoids in the roots. Methods: The objects of the study were 15 individual plants, selected within examined population and cloned in order to obtain a sufficient amount of raw material. The total content of flavonoids in roots was determined according to Polish Pharmacopeia 6th. The qualitative analysis of flavonoids was carried out using HPLC, Shimadzu chromatograph. Results: The dry mass of roots ranged from 25.88 to 56.14 g × plant-1. The total content of flavonoids (expressed as a quercetin equivalent) varied between 0.17 and 0.52% dry matter (DM). Nine compounds were detected within the group, with oroxylin A 7-Oglucuronide (346.90-1063.00 mg × 100 g-1 DM) as a dominant, which differentiated investigated clones at the highest degree (CV=0.27). Baicalin (391.40-942.00 mg × 100 g-1 DM), wogonoside (324.00-641.10 mg × 100 g-1 DM) and hesperetine 7-O-glucoside (163.00-346.32 mg × 100 g-1 DM) were also present in a considerable amounts. Clone 7 was distinguished by the highest content of all investigated compounds, except wogonin and oroxylin A 7-O-glucuronide. Conclusions: Results obtained in present study show a high variability within Baical skullcap investigated population in respect of flavonoid compounds detected in roots. Thus, the results may be used in future investigations concerning the selection and breeding of this species.

Scutellaria baicalensis, the golden herb from the garden of Chinese medicinal plants

Scutellaria baicalensis Georgi, or Chinese skullcap, has been widely used as a medicinal plant in China for thousands of years, where the preparation from its roots is called Huang-Qin. It has been applied in the treatment of diarrhea, dysentery, hypertension, hemorrhaging, insomnia, inflammation and respiratory infections. Flavones such as baicalin, wogonoside and their aglycones baicalein wogonin are the major bioactive compounds extracted from the root of S. baicalensis. These flavones have been reported to have various pharmacological functions, including anti-cancer, hepatoprotection, antibacterial and antiviral, antioxidant, anticonvulsant and neuroprotective effects. In this review, we focus on clinical applications and the pharmacological properties of the medicinal plant and the flavones extracted from it. We also describe biotechnological and metabolic methods that have been used to elucidate the biosynthetic pathways of the bioactive compounds in Scutellaria.

H2O2 Improves Quality of Radix scutellariae Through Anti-oxidant Effect

Introduction:

The correlation between the quality and geographical origin of herbal medicine was traced back to Tang Dynasty in China, more than 1200 years, and the effects of ecological environments on the secondary metabolites such as flavonoids have been confirmed. However, little is known about how the adversity impacts on the quality. Reactive oxygen species (ROS) may be medium between the ecological environment and the secondary metabolism.

Materials and Methods:

The fresh roots of Scutellaria baicalensis Georgi were treated with 0.002 μmol/L, 0.2 μmol/L, and 20 μmol/L H₂O₂, respectively. A stress model was established to elucidate the change of secondary metabolism, anti-oxidant enzyme system, and enzymes relating to flavonoids.

Results:

The activities of superoxide dismutase, catalase and peroxidase decreased. Too much H₂O₂, firstly, boosted transformation of flavonoids glycoside into aglucon with the most remarkable activities through UDP-glucuronate baicalein 7-O-glucuronosyltransferase (UBGAT), and β-glucuronidase (GUS), then regulated the gene expression of phenylalanine ammonialyase, GUS, and UBGAT, and increased the contents of flavones, motivated the flavonoid glycoside converting into aglucon. With this action, the flavones displaced the anti-oxidant enzymes. The higher the dosage, the more baicalein and wogonin increased, the later they took action.

Conclusion:

The plant secondary metabolites to keep ROS constant are identical to the effective materials in clinic. They are closely linked. H₂O₂ can improve flavones, especially the aglucon, and further increased the quality of herbal medicine, which possesses very important value in medical practice.

SUMMARY

H₂O₂ decreasing the activities of CAT and POD lead to accumulation of more H₂O₂. Excess of H₂O₂ up-regulated PAL, BUG, promote biosynthesis of flavones, and enhance the nonenzyme system. “↑” and “↓” represent activity or content “up” and “down” respectively.

Optimization of the extraction of total flavonoids from Scutellaria baicalensis Georgi using the response surface methodology

The response surface methodology (RSM) was used to optimize the conditions for total flavonoid extraction from Scutellaria baicalensis Georgi. The influences of the ethanol concentration, extraction time, temperature, and the liquid-solid ratio on flavonoid yield were investigated. Based on ANOVA results, a second-order quadratic polynomial model could be applied to characterize the extraction process. The following optimal extraction conditions were identified: ethanol concentration, 52.98 %; extraction time, 2.12 h; extraction temperature, 62.46 °C; and liquid-solid ratio, 35.23. The predicted extraction yield was 19.437 mg/g when these optimal conditions were used. The proposed method was successfully employed to extract flavonoids from S. baicalensis.

Antiradical and antioxidant activity of flavones from Scutellariae baicalensis radix

We evaluated the antioxidant properties of four main flavones from Scutellaria baicalensis: baicalein, wogonin and their glucuronides - baicalin and wogonoside. We used three in vitro assays: free radical scavenging with 2,2'-diphenylpicrylhydrazyl radical, transition metal ions reducing power by phosphomolybdenum assay and inhibition of the hydroxyl radical-induced peroxidation of linoleic acid assay. All flavones have antioxidant capacity, which differs depending on the structure and mechanisms of activity. In all tests, only baicalein - the aglycone with three adjacent hydroxyl groups - exhibited consistent antioxidant effect. Wogonin protected linoleic acid against oxidation. Baicalin displayed less potent antioxidant properties whereas wogonoside did not have significant antioxidant activity.

Cytotoxic and antioxidant properties of selected Scutellaria species from the Western Ghats of Peninsular India

CONTEXT

Scutellaria (Lamiaceae), commonly known as 'Skullcaps', has been extensively used in Traditional Chinese Medicine (TCM). Recently, much emphasis has been given to this genus due to the rich source of bioflavonoids that contribute to its biological properties. Therefore, different species of Scutellaria are being explored worldwide.

OBJECTIVES

Cytotoxic, antioxidant, and phytochemical properties of Scutellaria colebrookiana Benth and S. violacea (Heyne ex Benth) Don collected (October 2009-February 2010) from Western Ghats of India have been analysed.

MATERIALS AND METHODS

In vitro cytotoxicity and free radical scavenging effects of root extracts in various solvents were analysed. Spectrophotometric and HPLC methods were performed for phytochemical analysis.

RESULTS

Chloroform extract exhibited significant cytotoxicity in Dalton's Lymphoma Ascites (DLA) and Ehrlich Ascites Carcinoma (EAC) cells with IC(50) values 150 and 140 µg/mL for S. colebrookiana and 250 and 280 µg/mL for S. violacea, respectively. Moreover, the extract was effective in scavenging free radicals and inhibiting membrane peroxidation in vitro with IC(50) values 158.3 and 167.5 (superoxide), 17.5 and 28.0 (hydroxyl), 76.25 and 69.75 (DPPH), 24.5 and 28.0 (ABTS), 69.75 and 64.6 (lipid peroxidation), 41 and 31.5 µg/mL (erythrocyte hemolysis), respectively. Antioxidant effect observed with acetone extract was also comparable to that of chloroform extract. Phytochemical screening revealed the presence of baicalein.

DISCUSSION AND CONCLUSION

Scutellaria species of Western Ghats showed cytotoxic and antioxidant potential and the presence of baicalein. This suggests that S. colebrookiana and S. violacea could be used as alternative sources for baicalein in view of the reported scarcity of S. baicalensis.

The genus Scutellaria an ethnopharmacological and phytochemical review

Scutellaria (HUANG QIN) (Lamiaceae), which includes about 350 species commonly known as skullcaps, is widespread in Europe, the United States and East Asia. Some species are taken to clear away the heat-evil and expel superficial evils in traditional Chinese medicine (TCM). The present paper reviews the ethnopharmacology, the biological activities and the correlated chemical compounds of Scutellaria species. More than 295 compounds have been isolated, among them flavonoids and diterpenes. Studies show that Scutellaria and its active principles possess wide pharmacological actions, such as antitumor, anti-angiogenesis, hepatoprotective, antioxidant, anticonvulsant, antibacterial and antiviral activities. Currently, effective monomeric compounds or active parts have been screened for pharmacological activity from Scutellaria in vivo and in vitro. Increasing data supports application and exploitation for new drug development.

Antimutagenic activity and radical scavenging activity of water infusions and phenolics from ligustrum plants leaves

Water infusions of Ligustrum delavayanum and Ligustrum vulgare leaves and eight phenolics isolated therefrom have been assayed in vitro on ofloxacin-induced genotoxicity in the unicellular flagellate Euglena gracilis. The tested compounds luteolin, quercetin, luteolin-7-glucoside, luteolin-7-rutinoside, quercetin-3-rutinoside, apigenin-7-rutinoside, tyrosol and esculetin inhibited the mutagenic activity of ofloxacin (43 microM) in E. gracilis. Water infusions from leaves of L. delavayanum and L. vulgare showed higher antimutagenic effect (p(t) < 0.001). The activity of these samples against ofloxacin (86 microM)-induced genotoxicity was lower, but statistically significant (p(t) < 0.05), excluding the water infusion of L. delavayanum leaves (p(t) < 0.01). Efficacy of quercetin, luteolin-7-rutinoside, apigenin-7-rutinoside was insignificant. The antimutagenic effect of most phenolics we studied could be clearly ascribed to their DPPH scavenging activity, substitution patterns and lipophilicity.

Antioxidant and free radical scavenging activities of some medicinal plants from the Lamiaceae

Antioxidative effects of methanolic extracts from six wild European Lamiaceae species have been studied with the use of three in vitro assays. The ability of scavenging free radicals was measured by DPPH reduction spectrophotometric assay. The reducing potential towards transition metals was tested by phosphomolybdenum method and the inhibition of lipid oxidation was tested by Fe/ascorbate system with photometric TBARS detection. All studied herbs exposed strong antioxidant capability, but the results were different for each species depending on the applied test. In DPPH scavenging the order from strongest to the weakest was: Leonurus cardiaca, Lamium album, Marrubium vulgare, Stachys officinalis, Lamium purpureum, Galeopsis speciosa. With phosphomolybdenum method the extract of S. officinalis was the strongest in both 40 degrees Celsius and 90 degrees Celsius but other species acted differently in both temperatures. In lipid peroxidation assay, the maximum inhibition of 78% was reached by S. officinalis and M. vulgare, whereas for both Lamium sp. and L. cardiaca slightly exceeded 70% and for G. speciosa reached 65%. The observed differences indicate the complexity of involved mechanisms and support the necessity of combining several assays in studying the antioxidant potential of medicinal plants.

Supercritical CO2 extraction and purification of compounds with antioxidant activity

Supercritical fluid extraction (SCFE), based on the utilization of a fluid under supercritical conditions, is a technology suitable for extraction and purification of a variety of compounds, particularly those that have low volatility and/or are susceptible to thermal degradation. The interest in SCFE is promoted by legal limitations of conventional solvents for food and pharmaceutical uses. The physicochemical properties of supercritical CO2 (higher diffusivity, lower viscosity, and lower surface tension than conventional solvents) facilitate mass transfer and allow an environmentally friendly operation. This article presents a comprehensive compilation of data on the supercritical CO2 extraction of antioxidant compounds from vegetal materials, with particular attention to those of a phenolic nature. Aspects concerning the supercritical operation for extraction and fractionation of antioxidants compounds are considered, including equilibrium solubility of pure compounds and effects of the operational conditions on the antioxidant activity of isolated fractions. The data are compared to those reported for synthetic antioxidants and natural extracts obtained by conventional solvent extraction from vegetal matrices.

Flavones and flavone synthases

Within the secondary metabolite class of flavonoids which consist of more than 9000 known structures, flavones define one of the largest subgroups. Their natural distribution is demonstrated for almost all plant tissues. Various flavone aglyca and their O- or C-glycosides have been described in the literature. The diverse functions of flavones in plants as well as their various roles in the interaction with other organisms offer many potential applications, not only in plant breeding but also in ecology, agriculture and human nutrition and pharmacology. In this context, the antioxidative activity of flavones, their use in cancer prevention and treatment as well as the prevention of coronary heart disease should be emphasized. The therapeutic potential of flavones makes these compounds valuable targets for drug design, including recombinant DNA approaches. The biosynthesis of flavones in plants was found to be catalyzed by two completely different flavone synthase proteins (FNS), a unique feature within the flavonoids. The first, FNS I, a soluble dioxygenase, was only described for members of the Apiaceae family so far. The second, FNS II, a membrane bound cytochrome P450 enzyme, has been found in all other flavone accumulating tissues. This phenomenon is particularly of interest from the evolutionary point of view concerning the flavone biosynthesis and functions in plants. Recently, FNS I and FNS II genes have been cloned from a number of plant species. This now enables detailed biochemical and molecular characterizations and also the development of direct metabolic engineering strategies for modifications of flavone synthesis in plants to improve their nutritional and/or biopharmaceutical value.

Cytotoxic effects of the main active components from three Chinese herbal medicines on N-methyl-N-nitro-N-nitrosoguanidine transformed GES-1 cells

AIM: To investigate the cytotoxic effects of Panax Notogengsing Saponin (PNS), Astragalin Saponin (AS) and Baicalin (Ba), the main active components from 3 Chinese herbal medicines, on an immortalized human gastric epithelial cell line GES-1 and the N-methyl-N-nitro-N- nitrosoguanidine (MNNG) transformed GES-1 cells (MC cells).

METHODS: GES-1 cells were transformed by 2×10^-5 mol/L MNNG. The transformed cells were named as MC cells. MC cells were treated with the 3 medicines alone or in different combinations. Cell viability was detected by MTT assay and soft agar colony formation assay, while apoptosis/necrosis were determined by electron microscopy, fluoroscopy and flow cytometry with annexin V staining.

RESULTS: PNS, AS and Ba inhibited the growth of GES-1 and MC cells in a dose and time-dependent manner. The colony formation efficiency in soft agar of MC cells was also decreased after treated with PNS, AS, Ba alone or in combination (P<0.05 or P<0.01vs control group). The 3 medicines induced apoptosis and/or necrosis of MC cells time-dependently. These effects were greatly enhanced when two or three of these medicines were used together (P<0.05 or P<0.01 vs 3 medicines used alone). The most potent combination was PNS+AS+Ba, followed by PNS+AS, AS+Ba and PNS+Ba, in a decreasing order.

CONCLUSION: PNS, AS and Ba can inhibit cell growth and induce cell death on MC cells. The cell death is partially caused by cell apoptosis. These effects can be enhanced to different extent by different combinations of these drugs.

Non-aqueous capillary electrophoresis for simultaneous separation and determination of three major active components in traditional medicinal preparations

A simple and sensitive non-aqueous capillary electrophoresis method has been developed for simultaneous assay of three bioactive components (puerarin, daidzein and wogonin) in three traditional medicinal preparations for the first time. Optimum separation of the analytes was obtained on a 47 cm x 75 microm i.d. capillary using a non-aqueous buffer system of 20% acetonitrile, 25 mm ammonium acetate and apparent pH 9.00, with applied voltage and capillary temperature of 20 kV and 16 degrees C, respectively. The relative standard deviations (RSDs) of the migration times and the peak areas of the three analytes were in the ranges 2.5--4.0% and 3.2--3.9%, respectively. Detection limits of puerarin, daidzein and wogonin were 0.090, 0.145 and 0.090 microg mL(-1), respectively. In the tested concentration range, good linear relationships (correlation coef fi cients: 0.9998 for puerarin, 0.9998 for daidzein and 0.9978 for wogonin) between peak areas and concentrations of the analytes were observed. This method has been successfully applied to simultaneous determination of the three bioactive components with recoveries from 91.0 to 114.0%.