Effect of Liquiritigenin on Intestinal Flora in Ovariectomized APP/PS1 Transgenic Mice / 中山大学学报(医学科学版)

ObjectiveTo investigate the effect of liquiritigenin （LG） on intestinal flora in menopausal APP/PS1 mice. MethodsA total of forty 3-month-old female APP/PS1 mice were randomly divided into sham surgery group （n=20） and ovariectomy group （n=20）. Seven days after surgery， the ovariectomy group was randomly divided into ovariectomy control group （OVX， n=10）， ovariectomy + liquiritigenin treatment group （OVX + LG， n=10）， and the sham surgery group was randomly divided into liquiritigenin treatment group （LG， n=10） and reagent control group （Sham， n=10）， and ten C57BL/6J mice were taken as WT group. The dose of LG group and OVX + LG group was 30 mg•kg-1•d-1. After 90 days of drug treatment， fecal samples were gathered， genomes were extracted， and intestinal flora were analyzed by 16S rDNA Amplicon Sequencing. Morris water maze was performed to evaluate learning and memory abilities of mice. Immunofluorescence was used to observe the deposition of senile plaques （SP） in the brain of mice. ResultsThe results of water maze showed that LG significantly improved the learning memory ability of APP/PS1 mice with/without OVX （P<0.05）， and reduced the number of SPs in the brain of APP/PS1 mice with/without OVX， and the differences were statistically significant （P<0.000 1）. 16s rDNA sequencing analysis of the relative abundance of gut microbiota proved that LG treatment significantly increased the relative abundance of Firmicutes and Lactobacillus （P<0.05） and reduced the relative abundance of harmful bacteria belong to Bacteroidetes （P<0.05） in APP/PS1 mice intestines with/without menopause. After LG treatment， the relative abundance of Allobaculun elevated in the intestines of APP/PS1 mice， while declined in the intestines of menopausal APP/PS1 mice， but the difference was not statistically significant. LEfSe analysis revealed the bacteria with the most differential abundance of the gut microbiota of WT mice were Firmicutes， Bacillus， and Lactobacillales （P<0.05）； Lactobacillus reuteri had a greater influence on the LG group （P<0.05）； Bacteroidia， Bacteroidales and Bacteroides gathered in the intestines of mice in the Sham group （P<0.05）. Firmicutes and Allobaculum were the dominant in the WT group （P<0.05）； Bacteroides， Bacteroidia and Bacteroidales were more abundant in the Sham group（P<0.05）； Bacterroidaceae and Bacteroides had the most differential abundances in the OVX group （P<0.05）； Lactobacillaceae and Lactobacillus were more abundant in the intestines in the OVX + LG group （P<0.05）. ConclusionLG could improve the ratio of beneficial and harmful bacteria in the intestines of APP/PS1 mice before and after menopause. Liquiritigenin treatment showed consistent variations in intestinal flora in APP/PS1 mice with or without ovariectomy. It is presumed that menopausal APP/PS1 mice have lipid metabolism disorders which requires further study.

Development of liquiritigenin-phospholipid complex with the enhanced oral bioavailability / 中国天然药物

In the present study, liquiritigenin-phospholipid complex (LPC) was developed and evaluated to increase the oral bioavailability of liquiritigenin. A single-factor test methodology was applied to optimize the formulation and process for preparing LPC. The effects of solvent, drug concentration, reaction time, temperature and drug-to-phospholipid ratio on encapsulation efficiency were investigated. LPCs were characterized by UV-visible spectroscopy, differential scanning calorimetry (DSC), fourier transform infrared spectroscopy (FTIR), and powder X-ray diffractometry (PXRD). The apparent solubility and n-octanol/water partition coefficient were tested. The pharmacokinetic characteristics and bioavailability of the LPC were investigated after oral administration in rats in comparison with liquiritigenin alone. An LPC was successfully prepared. The optimum level of various parameters for liquiritigenin-phospholipid complex was obtained at the drug concentration of 8 mg·mL

A new diphenylpropanoid from Cassia floribunda / 中草药

Objective: To study the chemical composition of the stems and leaves of Cassiafloribunda. Methods: The chemical constituents from stems and leaves of C. floribunda were isolated by silica gel MCI, RP-18, TLC, and HPLC methods. Their structures were elucidated by spectroscopic methods and physicochemical properties. Results: Eighteen compounds were isolated from the 90% EtOH extract of C. floribunda and their structures were established ascassia cis-transdiphenylpropanoid(1), ethyl p-hydroxycinnamate (2), shonanin(3), dibutyl phthalate(4), 1,6,8-trihydroxyl-3-methyl-anthraquinone (5), 2,5-dimethyl-7-hydroxyl-chromogen, (6), 2-(2'-hydroxypropyl)-5-methyl-7-hydroxytryptophan(7), 4',7-dihydroxy-5-methoxy flavone(8), chrysoeriol(9), kaempferol(10), apigenin(11), 3-methoxy quercetin(12), 6-demethoxycapillarisin(13), 7,4'-dihydroxyflavone(14), luteolin(15), butin(16), liquiritigenin(17) anderiodictyol(18). Conclusion: Compound 1 is a new compound, and 2-18 are isolated from this plant for the first time.At the moment,2-4, 8, 9, 11, 13, 14, 16-18 are isolated from Cassia for the first time.

7-hydroxy sulfonation of liquiritigenin by recombinant SULT1A3 enzyme and HEK-SULT1A3 cells / 中国中药杂志

In this study,liquiritigenin sulfonation was characterized using recombinant human sulfotransferases( SULTs). The chemical structure of liquiritigenin sulfate was determined by ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry( UPLC-Q-TOF-MS/MS). Then model fitting and parameter estimation were performed using the Graphpad Prism V5 software. Various SULT enzymes( SULT1 A1,1 A2,1 A3,1 B1,1 C2,1 C4,1 E1 and 2 A1) were able to catalyze the formation of liquiritigenin-7-O-sulfate. Sulfonation of liquiritigenin-7-hydroxy( 7-OH) by these eight SULT enzymes consistently displayed the classical Michaelis-Menten profile. According to the intrinsic clearance( CLint) value,the sulfonation rates of liquiritigenin-7-OH by expressed SULT enzymes followed the following rank order: SULT1 C4 > SULT1 A3 > SULT1 E1 > SULT1 A1 > SULT1 A2 > SULT1 B1 >SULT1 C2>SULT2 A1. Further,liquiritigenin-7-O-sulfonation was significantly correlated with the SULT1 A3 protein levels( P<0. 05).Then,human embryonic kidney( HEK) 293 cells over expressing SULT1 A3( named as HEK-SULT1 A3 cells) were conducted. As a result,liquiritigenin-7-O-sulfate( L-7-S) was rapidly generated upon incubation of the cells with liquiritigenin. Consistent with SULT1 A3,sulfonation of liquiritigenin-7-OH in HEK-SULT1 A3 cells also followed the Michaelis-Menten kinetics. The derived Vmaxvalues was( 0. 315±0. 009) μmol·min-1·g-1,Kmwas( 7. 04±0. 680) μmol·L-1,and CLintwas( 0. 045±0. 005) L·min-1·g-1. Moreover,the sulfonation characters of liquiritigenin( 7-OH) in SULT1 A3 were strongly correlated with that in HEK-SULT1 A3 cells( P<0. 001).The results indicated that HEK-SULT1 A3 cells have shown the catalytic function of SULT1 A3 enzymes. In conclusion,liquiritigenin was subjected to efficient sulfonation,and SULT1 A3 enzyme plays an important role in the sulfonation of liquiritigenin-7-OH. Significant sulfonation should be the main reason for the low bioavailability of liquiritigenin. In addition,HEK-SULT1 A3 cells were conducted and successfully used to evaluate liquiritigenin sulfonation,which will provide an appropriate tool to accurately depict the sulfonation disposition of liquiritigenin in vivo.

Effects of Chinese herb ingredients with different properties on OAT4, URAT1 and serum uric acid level in acute hyperuricemia mice / 中草药

Objective To study the effects of Chinese herb ingredients with different properties on transporters (URAT1 and OAT4) involved in renal urate reabsorption and serum uric acid level in acute hyperuricemia mice. Methods The OAT4, URAT1- overexpressed monoclonal cell line (MDCK-hOAT4, HEK293-hURAT1) was constructed. The inhibition effect and the half maximal inhibitory concentration (IC50) of different ingredients to transport activity of OAT4 and URAT1 mediating 14C-uric acid were determined. The effects of protocatechuic, liquiritigenin and isoliquiritigenin on serum uric acid levels in acute hyperuricemia mice were studied by the acute hyperuricemia mice induced by potassium oxonate and xanthine. Results The results indicated that nobiletin,liquiritigenin, isoliquiritigenin, licochalcone A with bitter flavor showed strong inhibition to OAT4. The IC50 of nobiletin, liquiritigenin, isoliquiritigenin, and licochalcone A on OAT4 were 0.556 μmol/L, 18.40 μmol/L, 6.831 μmol/L, and 6.825 μmol/L, respectively. Protocatechuic acid and liquiritigenin showed strong inhibition to URAT1 with IC50 of 7.709 μmol/L and 14.54 μmol/L, respectively. Liquiritigenin can significantly reduce the level of serum uric acid of acute hyperuricemia mice, increase the excretion of uric acid, and reduce the level of serum creatinine and blood urea nitrogen. Conclusion Nobiletin, liquiritigenin, isoliquiritigenin and licochalcone A can inhibit the transport activity of OAT4, while protocatechuic acid and liquiritigenin can inhibit the transport activity of URAT1. Liquiritigenin can significantly reduce the level of serum uric acid in acute hyperuricemia mice and protect kidney, the mechanism of which may be associated with the decreasing reabsorption of uric acid by inhibiting the activity of URAT1 and OAT4.

Box-Behnken response surface method optimized technological research of ultrafiltration-complexation extraction and back extraction technology to prepare liquiritigenin / 中草药

Objective: A technological route was established for preparing liquiritigenin from the licorice ultrafiltrate. Methods: U5(53) uniform design was used to optimize the ultrafiltration process with the retention rate of liquiritigenin as the index; Box-Behnken response surface method was used to optimize the complexation extraction process with the extraction rate of liquiritigenin as the index; The technological condition of back extraction of liquiritigenin was determined by the liquiritigenin stripping rate. Results: The optimal ultrafiltration conditions for liquiritigenin were inorganic ceramic membranes with a pore size of 10 nm, a pressure of 0.12 MPa, and solution temperature of 25 ℃, retention rate of liquiritigenin was 98.74%. Optimum complexation extraction conditions were as following: 1% TRPO complexing agent, extraction for 10 min in 5 mL organic phase solution, the extraction rate of liquiritigenin was 99.44%; The 12.5 mmol/L NaOH aqueous solution was the best back-extractant, and the back extraction rate was 98.88%. Conclusion: As a new Chinese medicine extraction technology, ultrafiltration-complexation extraction and back extraction technology have the advantages of high selectivity, high efficiency, and recycling of extractant, which can provide a new preparation technology for the research of liquiritigenin.

Preparation of flavonoids from Glycyrrhiza uralensis by two-dimensional reversed-phase liquid chromatography / 中草药

Objective To develop a systematic chromatography separation method for flavonoids from Glycyrrhiza uralensis Fisch. (GU). Methods A new method for the separation of effective parts and monomers of flavonoids from GU by two-dimensional reversed-phase liquid chromatography was developed using the self-developed preparation chromatography plant system with independent intellectual property rights. Flavonoids compounds were enriched with specific adsorption materials. The separation conditions of the chromatography were optimized by the chromatographic separation expert system software, and the loading weight of samples and the enrichment times of a separation were investigated. Results The process of chromatography separation of flavonoids from GU had good precision and reproducibility with C18 as separation and enrichment solid phase and the methanol/water and acetonitrile/water as mobile phase of one-dimensional and two-dimensional chromatography system. The dilution solution which used for one-dimensional and two-dimensional enrichment chromatography was water. The flow rate of gradient elution and dilution enrichment solution was 21 mL/min. The sample loading amount of chromatography separation was 300 mg each time. A total of 16 flavonoids parts contained stable chemical composition were obtained by the repeatable separation method after three times of enrichment. Nine pure compounds were obtained and identified by NMR and MS, which were liquiritin, liquiritigenin, formononetin, echinatin, 7,4'-dihydroxyflavone, 4'-O-[β-D-apio-D-furanosyl-(1→2)-β-D-glucopyranosyl] liquiritigenin, isoliquiritigenin, glycyrol, and glycycoumarin. Conclusion The study can provide a certain reference value for the systematic separation and cognition for flavonoids from GU.

The Memory-Enhancing Effects of Liquiritigenin by Activation of NMDA Receptors and the CREB Signaling Pathway in Mice

Liquiritigenin (LQ) is a flavonoid that can be isolated from Glycyrrhiza radix. It is frequently used as a tranditional oriental medicine herbal treatment for swelling and injury and for detoxification. However, the effects of LQ on cognitive function have not been fully explored. In this study, we evaluated the memory-enhancing effects of LQ and the underlying mechanisms with a focus on the N-methyl-D-aspartic acid receptor (NMDAR) in mice. Learning and memory ability were evaluated with the Y-maze and passive avoidance tests following administration of LQ. In addition, the expression of NMDAR subunits 1, 2A, and 2B; postsynaptic density-95 (PSD-95); phosphorylation of Ca2+/calmodulin-dependent protein kinase II (CaMKII); phosphorylation of extracellular signal-regulated kinase 1/2 (ERK 1/2); and phosphorylation of cAMP response element binding (CREB) proteins were examined by Western blot. In vivo, we found that treatment with LQ significantly improved memory performance in both behavioral tests. In vitro, LQ significantly increased NMDARs in the hippocampus. Furthermore, LQ significantly increased PSD-95 expression as well as CaMKII, ERK, and CREB phosphorylation in the hippocampus. Taken together, our results suggest that LQ has cognition enhancing activities and that these effects are mediated, in part, by activation of the NMDAR and CREB signaling pathways.

In vitro metabolism of liquiritigenin in liver microsomes of different species / 中草药

Objective: To compare in vitro metabolic differences of liquiritigenin, an aglycone of liquiritin, among liver microsomes of different species, which would provide reference for further research and development of liquiritin. Methods: Metabolic stability and metabolic biotransformation were investigated after liquiritigenin was incubated with rat, mouse, human, dog, and monkey liver microsomes. Metabolic stability was evaluated using a substrate depletion approach, and the results were reported as "% liquiritigenin remaining", which was then used to calculate the in vitro half-life (t1/2). Metabolic biotransformation was characterized by metabolite profiling. Results: In liver microsomal incubation systems of five species, the t1/2 values of liquiritigenin for phase I were as follows: rat < mouse < human < monkey < dog, whereas for phase II, the metabolic rates were all fast and the remaining of liquiritigenin were all below 50% in 5 min except mouse. In addition, phase II metabolite profiling in monkey liver microsomes was identical to that of human, but marked differences were found between other species and human. Conclusion: The metabolic characteristics of liquiritigenin in monkey liver microsomes is most similar to that of human, then followed by dog, and marked differences existed between rat, mouse and human. Therefore, monkey or dog could be the animal model for further preclinical pharmacokinetic and toxicological studies.

Analysis on components exposing in rat plasma after oral administration of Baoerkang Powder / 中草药

Objective: To analyze the components exposing in rat plasma after oral administration of Baoerkang Powder, and to study the mechanism of Baoerkang Powder and pharmacokinetic behavior. Methods: Components absorbed in rat plasma after oral administration of Baoerkang Powder to rats were analyzed by UPLC tandem High-resolution mass spectrometer. The structures of Baoerkang Powder in rat plasma identified by comparing the retention time, molecular weight, and CID fragmentation patterns with their corresponding compounds reported in the literatures. Results: Twenty-three components in rat plasma were identified after oral administration of Baoerkang Powder to rats for 1 h, including five components confirmed by comparing retention time and information of mass with their reference substances, components confirmed were vitexin, liquiritigenin, hesperetin, glycyrrhetic acid, and ursolic acid. Conclusion: It is suggested that the method could be applied to quick analysis of the components exposing in rat plasma after oral administration of Baoerkang Powder, which is beneficial to studying its mechanism and pharmacokinetic behavior.

Preparation process of liquiritigenin injection / 中国药学杂志

OBJECTIVE: To optimize the preparation process of liquiritigenin injection. METHODS: Single factor experiment was carried out to determine the solvents, dosage of adjuvants, pH of solution, pyrogen removal method and sterilization process. RESULTS: The optimal conditions were determined as follows: liquiritigenin was dissolved in 40% propylene glycol solution at pH 4.0-6.0. Ultrafiltration was employed to remove bacterial endotoxin. The solution was sterilized at 121℃ (97 kPa) for 15 min. CONCLUSION: The established preparation process of liquiritigenin injection is reasonable and suitable for industrialized production.

LC-MS/MS Method for Quantification of Liquiritigenin in Rat Plasma: Application to Pharmacokinetic Study of Liquiritin / 中草药·英文版

Objective: A simple, sensitive, and rapid LC-MS/MS method has been established and validated for the determination of liquiritigenin (LG) in rat plasma. Methods: Naringenin was chosen as internal standard (IS). LG and IS were separated on a Diamonsil C18 analytical column with a mobile phase of methanol-10% methanol in water containing 0.5 mmol/L ammonium formate and 0.2% formic acid (55:45) at the isocratic flow rate of 0.6 mL/min for 10 min. The multiple reaction monitoring (MRM) was performed on a mass spectrometer in the negative ion mode with electro-spray ionization (ESI) source and the transition from precursor ion to product ion was m/z 255.0→119.0 for LG and m/z 271.0→151.0 for IS, respectively. Results: The linearity was acceptable in the range of 5-5000 ng/mL (r = 0.9973). The inter-day and intra-day accuracies were in the ranges of -0.09%-3.25% and -5.02%-9.21%, respectively. The precision was in the ranges of 3.60%-12.4% and 0.909%-6.89%, respectively. LG was stable in the course of analysis and storage. Conclusion: The LC-MS/MS method was successfully applied to the pharmacokinetic study for the first time in rats after ig and iv administration of liquiritin (LQ), a glycoside of LG, at pharmacologically effective levels.

Chemical Constituents from Roots of Millettia speciosa / 中草药·英文版

Objective To study the chemical constituents from the roots of Millettia speciosa. Methods The chemical constituents were isolated and purified by silica gel, Sephadex LH-20, and ODS column chromatography. The structures were identified by means of spectral data. Results Fifteen compounds were isolated and identified as naringenin (1), liquiritigenin (2), garbanzol (3), 7-hydroxy-6,4′- dimethoxyisoflavone (4), calycosin (5), 2′,5′,7-trihydroxy-4′-methoxyisoflavone (6), 2′-hydroxybiochanin A (7), 6-methoxycalopogonium isoflavone A (8), demethylmedicarpin (9), 4,4′-dihydroxy-2′-methoxychalcone (10), 2′,4′-dihydroxy-4-methoxychalcone (11), rhododendrol (12), secoisolariciresinol (13), bisdihydrosiringenin (14), and polystachyol (15). Conclusion All compounds are obtained from this plant for the first time.

Cancer therapy using natural ligands that target estrogen receptor beta / 中国天然药物

Estrogen receptor beta (ERβ) is one of the two key receptors (ERα, ERβ) that facilitate biological actions of 17β-estradiol (E2). ERβ is widely expressed in many tissues, and its expression is reduced or lost during progression of many tumors. ERβ facilitates estrogen signaling by both genomic (classical and non-classical) and extra-nuclear signaling. Emerging evidence suggests that ERβ functions as a tissue-specific tumor suppressor with anti-proliferative actions. Recent studies have identified a number of naturally available selective ERβ agonists. Targeting ERβ using its naturally available ligands is an attractive approach for treating and preventing cancers. This review presents the beneficial actions of ERβ signaling and clinical utility of several natural ERβ ligands as potential cancer therapy.

Simultaneous Determination of Four Constituents in Roots and Knotty Rhizome of Glycyrrhiza uralensis by HPLC / 世界科学技术-中医药现代化

This study was aimed to establish an HPLC method for the determination of liquiritin, isoliquiritin, liquiritigenin and glycyrrhizic acid in roots and knotty rhizome of Glycyrrhiza uralensis. The analysis was performed on a Diamonsil C18 column (250 mm í 4.6 mm, 5 μm) by using a gradient elution with mobile phase of water, phosphoric acid, acetonitrile at the flow rate of 1.0 mL·min-1. The detection wavelength was 276 nm (0~18 min), 360 nm (18~24 min), 276 nm(24~30 min), and 250 nm (30~65 min). The column temperature was set at 30℃. The results showed that the linear range of iquiritin, isoliquiritin, liquiritigenin, glycyrrhizic acid was 0 . 108 5~1 . 085、0 . 016 8~0 . 168、0 . 0049 4~0 . 049 4、0 . 407~4 . 07μg , respectively . The average recoveries of four constituents were 96.61%~100.89%, with RSD ≤ 0.81%. The contents of four constituents in roots of five batches were 0.513%, 0.072 9%, 0.048 4%, and 1.945%, respectively. Contents of four constituents in knotty rhizome from two batches were 0.456%, 0.063 6%, 0.036 2%, and 1.630%, respectively. It was concluded that there was good linear relationship between the response and concentration. Contents of four constituents in knotty rhizome were basically the same as those in the roots. The knotty rhizome can be used as raw material for the extraction of active components.

Analysis on changing rules of four active components alignment in Glycyrrhizae Radix et Rhizoma Praeparata cum Melle and its compatibility carrier / 中草药

Objective: To study the changing rules of Glycyrrhizae Radix et Rhizoma Praeparata cum Melle (GRRPM) with the active components alignment (ACA, liquiritin-liquiritigenin-glycyrrhizin acid-isoliquiritinin) of tonifying spleen and replenishing qi. Methods: Taking single herbs, their medicine pairs, or their medicine compounds as test sample, the sample solution was prepared by traditional water decoction and determined by HPLC. Results: The contents of liquiritin-liquiritigenin-glycyrrhizin acid-isoliquiritinin in GRRPM were (12.14±0.31), (3.25±0.19), (38.75±1.77), and (1.40±0.25) mg/mL; The ACA contents in GRRPM-Ginseng Radix et Rhizoma (GRR) were (2.87±0.04), (0.74±0.02), (6.42±0.18), and (0.37±0.03) mg/mL; The ACA contents in GRRPM-Atractylodis Macrocephalae Rhizoma (AMR) were (5.99±0.01), (2.16±0.09), (22.40±1.80), and (0.77±0.02) mg/mL; The ACA contents in Sijunzi Decotion (SD) were (2.99±0.03), (0.81±0.04), (10.05±0.31), and (0.32±0.03) mg/mL. Conclusion: Four main active components in the efficacy of the test components have almost the same change rule: GRRPM≤GRRPM-AMR≤SD≤GRRPM-GRR; The percentage change intervals of the ACA (liquiritin-liquiritigenin-glycyrrhizin acid-isoliquiritinin) are (7.76-9.34):(2.00-2.81):(17.35-31.41):1. The total contents in single herbs are three times as much as in compatibility components, so the Chinese materia medica (CMM) are often used in the type of formula, which indicates that the utilized space of ACA resources is larger, ACA has the obvious effect of correspondence, and the quality standard of CMM should be marked ACA and medicinal components of biological potency as indicators.

Effects of flavonoids from Glycyrrhizae Radix on function and expression of P-glycoprotein in Caco-2 cells / 中草药

Objective: To study the effects of the flavonoids from Glycyrrhizae Radix (FGR) on the function and expression of P-glycoprotein (P-gp) in Caco-2 cells, and to further explore the detoxification mechanisms of FGR. Methods: Flow cytometry was used to study the effects of FGR on the uptake of Rhodamine 123, which showed the toxic efflux function of P-gp; Western blotting method was used to detect the expression level of P-gp in Caco-2 cells. Results: Compared with the control group, after treated with the total flavonoids from Glycyrrhizae Radix (TFGR) at the different concentration (5, 10, 50, and 100 μg/mL) for 1 h, the uptake of Rhodamine 123 in Caco-2 cells was decreased by 61.1%, 56.3%, 49.2%, and 45.4%; liquiritin, isoliquiritin, liquiritigenin, isoliquiritigenin, liquiritin apioside, and isoliquiritin apioside with the same dose significantly decreased the fluorescence intensity of Rhodamine 123 by 19.3%-37.9%. The expression levels of P-gp in Caco-2 cells were significantly increased (P < 0.01) after the co-incubation of TFGR (10-400 μg/mL) for 72 h, and liquiritin, isoliquiritin, liquiritigenin, and liquiritin apioside (5-400 μmol/L) had the similar functions, so did isoliquiritin and isoliquiritin apioside (10-400 μg/mL, P < 0.01). Conclusion: FGR could strengthen the function, up-regulate the expression of P-gp in Caco-2 cells, promote the efflux of toxic substances, and decrease the absorption of toxic substances, which could be one of the new mechanisms for Glycyrrhizae Radix detoxification.

Simultaneous determination of five index components in Glycyrrhizae Radix et Rhizoma and Longchai Decoction by HPLC / 中国药学杂志

OBJECTIVE: To establish a determination method of five index components to control the quality of Glycyrrhizae Radix et Rhizoma and Longchai Decoction. METHODS: An ODS C18 column (4.6 mm × 250 mm, 5 μm) was adopted; the mobile phase consisted of acetonitrile -0.05% phosphoric acid with gradient elution at the flow rate of 1 mL · min-1; the detection wavelength was 237 nm, and the column temperature was 30°C. RESULTS: The five index components achieved baseline separation, and the negative sample showed no interference. The linear ranges were 0.156 8-1.568 μg for liquiritin (r=0.999 7), 0.157 1-1.571 μg for isoliquiritin (r=0.999 8), 0.155 8-1.558 μg for liquiritigenin (r=0.999 6), 0.187 1-1.871 μg for glycyrrhizic (r=0.996 9) and 0.158 1-1.581 μg for isoliquiritigenin (r=0.999 5), respectively. The average recoveries were 101.47% (RSD=1.272%), 101.09% (RSD=1.937%), 101.14% (RSD=2.388%), 100.38% (RSD=1.448%) and 100.86% (RSD=1.759%), respectively (n=5). CONCLUSION: This method has good resolution and high precision, and can be used for the quality control of Glycyrrhizae Radix et Rhizoma and Longchai decoction.

Determination of Chlorogenic Acid,Liquiritigenin,Cinnamic Acid,and Monoammonium Glycyrrhetate in Tong Saimai Pellets by RP-HPLC / 广州中医药大学学报

Objective To establish a HPLC method for the simultaneous determination of chlorogenic acid,liquiritigenin,cinnamic acid,and monoammonium glycyrrhetate in Tong Saimai Pellets.Methods A Zorbax 80A Extend-C18 column was used.The mobile phase consisted of acetonitrile and 0.1% phosphoric acid,and was used for gradient elution.Chlorogenic acid,liquiritigenin,cinnamic acid and monoammonium glycyrrhetate were determined by dual wavelength,?s=276nm,?R=590nm.Results The linear range of chlorogenic acid was 0.0505~1.6160 ?g,and r=0.9999;the average recovery was 98.17%,and sR=4.28%(N=6).The linear range of liquiritigenin was 0.0252~0.8064 ?g,and r=0.9999;the average recovery was 93.76%,and sR=1.94%(N=6).The linear range of cinnamic acid was 0.0111~0.3552?g,and r=0.9999;the average recovery was 98.25%,and sR =2.72%(N=6).The linear range of monoammonium glycyrrhetate was 0.3300~10.5600?g,and r=0.9999;the average recovery was 102.6%,and sR=1.93%(N=6).Conclusion This method is convenient,rapid and accurate,and it can be used for quality control of the production of Tong Saimai Pellets.

Determination of liquiritin、liquiritigenin and iso-liquiritigenin in Licorice Mixture by HPLC / 中成药

Objective: To establish a HPLC method for the determination of liquiritin、 liquiritigenin and iso liquiritigenin in Licorice Mixture.Methods: A Cromasil C 18 column was used. the mobile phase was methanol 0.5% acetic acid for gradient elution. Liquiritin、 liquiritigenin and iso liquiritigenin were determined by dual wavelength, ? 1=276 nm,? 2=372 nm.Results: The linear range of liquiritin was 50.0～1250.0ng, r= 0.9999; The average recovery was 98.30%, RSD =1.01%( n= 6). The linear range of liquiritigenin was 5.0～125.0 ng, r= 0.9998; The average recovery was 98.01%, RSD =0.68%( n= 6). The linear range of iso liquiritigenin was 3.0～6.0 ng, r= 0.9999. The average recovery was 98.37%, RSD= 0.89%( n= 6). Conclusion: This method is convenient, rapid and accurate. It can be used for quality control in production of Licorice Mixture.