Analysis and comparison of Radix Glycyrrhizae (licorice) from Europe and China by capillary-zone electrophoresis (CZE)

Iron oxides based nanozyme sensor arrays for the detection of active substances in licorice

With the increasing applications of traditional Chinese medicines worldwide, authenticity identification and quality control are significant for them to go global. Licorice is a kind of medicinal material with various functions and wide applications. In this work, colorimetric sensor arrays based on iron oxide nanozymes were constructed to discriminate active indicators in licorice. Fe₂O₃, Fe₃O₄, and His-Fe₃O₄ nanoparticles were synthesized by a hydrothermal method, possessing excellent peroxidase-like activity that can catalyze the oxidation of 3,3',5,5' -tetramethylbenzidine (TMB) in the presence of H₂O₂ to produce a blue product. When licorice active substances were introduced in the reaction system, they showed competitive effect on peroxidase-mimicking activity of nanozymes, resulting in inhibitory effect on the oxidation of TMB. Based on this principle, four licorice active substances including glycyrrhizic acid, liquiritin, licochalcone A, and isolicoflavonol with the concentration ranging from 1 μM to 200 μM were successfully discriminated by the proposed sensor arrays. This work supplies a low cost, rapid and accurate method for multiplex discrimination of active substances to guarantee the authenticity and quality of licorice, which is also expected to be applied to distinguish other substances.

The Effect of Terpenoid Natural Chinese Medicine Molecular Compound on Lung Cancer Treatment

Among all malignant tumors in the whole universe, the incidence and mortality of lung cancer disease rank first. Especially in the past few years, the occurrence of lung cancer in the urban population has continued to increase, which seriously threatens the lives and health of people. Among the many treatments for lung cancer, chemotherapy is the best one, but traditional chemotherapy has low specificity and drug resistance. To address the above issue, this study reviews the five biological pathways that common terpenoid compounds in medicinal plants interfere with the occurrence and development of lung cancer: cell proliferation, cell apoptosis, cell autophagy, cell invasion, metastasis, and immune mechanism regulation. In addition, the mechanism of the terpenoid natural traditional Chinese medicine monomer compound combined with Western medicine in the multipathway antilung cancer is summarized.

A Comprehensive Review about the Molecular Structure of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2): Insights into Natural Products against COVID-19

In 2019, the world suffered from the emergence of COVID-19 infection, one of the most difficult pandemics in recent history. Millions of confirmed deaths from this pandemic have been reported worldwide. This disaster was caused by SARS-CoV-2, which is the last discovered member of the family of Coronaviridae. Various studies have shown that natural compounds have effective antiviral properties against coronaviruses by inhibiting multiple viral targets, including spike proteins and viral enzymes. This review presents the classification and a detailed explanation of the SARS-CoV-2 molecular characteristics and structure-function relationships. We present all currently available crystal structures of different SARS-CoV-2 proteins and emphasized on the crystal structure of different virus proteins and the binding modes of their ligands. This review also discusses the various therapeutic approaches for COVID-19 treatment and available vaccinations. In addition, we highlight and compare the existing data about natural compounds extracted from algae, fungi, plants, and scorpion venom that were used as antiviral agents against SARS-CoV-2 infection. Moreover, we discuss the repurposing of select approved therapeutic agents that have been used in the treatment of other viruses.

Glycyrrhizic Acid Inhibits SARS-CoV-2 Infection by Blocking Spike Protein-Mediated Cell Attachment

Glycyrrhizic acid (GA), also known as glycyrrhizin, is a triterpene glycoside isolated from plants of Glycyrrhiza species (licorice). GA possesses a wide range of pharmacological and antiviral activities against enveloped viruses including severe acute respiratory syndrome (SARS) virus. Since the S protein (S) mediates SARS coronavirus 2 (SARS-CoV-2) cell attachment and cell entry, we assayed the GA effect on SARS-CoV-2 infection using an S protein-pseudotyped lentivirus (Lenti-S). GA treatment dose-dependently blocked Lenti-S infection. We showed that incubation of Lenti-S virus, but not the host cells with GA prior to the infection, reduced Lenti-S infection, indicating that GA targeted the virus for infection. Surface plasmon resonance measurement showed that GA interacted with a recombinant S protein and blocked S protein binding to host cells. Autodocking analysis revealed that the S protein has several GA-binding pockets including one at the interaction interface to the receptor angiotensin-converting enzyme 2 (ACE2) and another at the inner side of the receptor-binding domain (RBD) which might impact the close-to-open conformation change of the S protein required for ACE2 interaction. In addition to identifying GA antiviral activity against SARS-CoV-2, the study linked GA antiviral activity to its effect on virus cell binding.

Potential and applications of capillary electrophoresis for analyzing traditional Chinese medicine: a critical review

Capillary electrophoresis (CE) presents a promising possibility for analyzing traditional Chinese medicine (TCM) due to its low reagent consumption, high analysis speed, and enhanced efficiency. Herein we review the employment of CE for analyzing the effective components in TCM and identifying TCM via a fingerprint. Furthermore, we discuss the application of state-of-the-art capillary electrophoresis modes for screening enzyme inhibitors and investigating the interactions between TCM and plasma proteins. The review concludes with recommendations for future studies and improvements in this field of research. The general development trend identified in this review indicates that the application of CE has significantly improved TCM assay performance.

Recent advances in chemical analysis of licorice (Gan-Cao)

Gan-Cao, or licorice, the dried roots and rhizomes of Glycyrrhiza uralensis, G.glabra, and G.inflata, has received considerable interest due to its extensive application in traditional Chinese medicine (TCM) prescriptions (60% approximately), clinical therapy, and as food additives world-wide. Chemical analysis is an important approach to understand the active pharmaceutical components in licorice and its prescriptions, as well as to develop novel methodologies for their quality assessment and control. This comprehensive review describes the advances in the chemical analysis, including sample preparation methods, qualitative and quantitative analysis and biological specimen analysis, based on 113 references for the recent years. Newly established methods are summarized, such as high performance thin layer chromatography (HPTLC), high performance liquid chromatography (HPLC), liquid chromatography tandem mass spectrometry (LC-MS), capillary electrophoresis (CE) and near infrared spectroscopy (NIR), which allows the identification, authentication, and simultaneous detection of multiple compounds in licorice with higher throughput and sensitivity. It is anticipated that this review could provide imperative information for improving the existing quality evaluation methods of licorice and afford scientific basis for further researches on the pharmacodynamic substances of licorice.

Metabolomics study of different parts of licorice from different geographical origins and their anti-inflammatory activities

Glycyrrhiza uralensis Fisch., known as licorice, is one of the most famous traditional Chinese medicines. In this study, we perform a metabolome analysis using liquid chromatography-tandem mass spectrometry to assign bioactive components in different parts of licorice from different geographical origins in Gansu province of China. Sixteen potential biomarkers of taproots from different geographical origins were annotated, such as glycycoumarin, gancaonin Z, licoricone, and dihydroxy kanzonol H mainly exist in the sample of Jiuquan; neoliquiritin, 6'-acetylliquiritin, licochalcone B, isolicoflavonol, glycyrol, and methylated uralenin mainly exist in Glycyrrhiza uralensis from Lanzhou; gancaonin L, uralenin, and glycybridin I mainly exist in licorice from Wuwei for the first time.

A novel symmetrical cyclooctenone from Radix Glycyrrhizae

A novel symmetrical structure, Gancao cyclooctenone A (1), was isolated from Radix Glycyrrhizae. The structure of the compound was established on the basis of the spectroscopic data including 1D and 2D NMR spectroscopy and mass spectrometry. Cytotoxic activities of compound 1 on A549 and Hela cell lines were evaluated and the IC₅₀ values were determined to be 63.21 and 45.82 μΜ, respectively.

A strategy for qualitative and quantitative profiling of glycyrrhiza extract and discovery of potential markers by fingerprint-activity relationship modeling

This study was to evaluate the quality consistency of glycyrrhiza extract and to explore the possible anti-oxidant components in combination with chromatographic fingerprint and bioactivity evaluation. Characteristic fingerprints of glycyrrhiza extract samples from different sources were generated by high performance liquid chromatography with diode array detector (HPLC-DAD) and evaluated using hierarchical clustering and similarity analysis. Compared with the conventional qualitative similarity evaluation method, the averagely linear quantified fingerprint method had an important quantitative similarity parameter supported by quantitative analysis, which was recommended in the fingerprint evaluation. Antioxidant activities of the glycyrrhiza extract samples were determined by DPPH (2, 2-diphenyl-1-picryldrazyl) radical scavenging assays. In addition, the fingerprint-efficacy relationship was investigated by the chemical fingerprints and the anti-oxidant activities utilizing partial least squares model, which was capable of exploring and discovering the bioactive components of glycyrrhiza extracts. Therefore, the present study provided a powerful strategy to evaluate the holistic quality consistency of medicinal plant.

Shaoyao-Gancao Decoction alleviated hyperandrogenism in a letrozole-induced rat model of polycystic ovary syndrome by inhibition of NF-κB activation

Shaoyao-Gancao Decoction (SGD) has been widely used for the treatment of gynopathy. The present study aimed to evaluate the therapeutic effect and potential mechanism of SGD on hyperandrogenism in polycystic ovary syndrome (PCOS) rats. In the present work, SGD was orally administrated to the PCOS rats at the dose of 12.5, 25, and 50 g/kg/d for 14 consecutive days. UPLC–MS/MS was performed to identify the main chemical components of SGD. Body weight, ovarian weight, cystic dilating follicles, and serum levels of steroid hormones were tested to evaluate the therapeutic effect of SGD. In order to further clarify the underlying mechanism, we also measured mRNA and the protein levels of NF-κB, NF-κB p65, P-NF-κB p65, and IκB by RT-qPCR and Western blotting techniques. Our results showed that SGD treatment significantly alleviated hyperandrogenism in PCOS rats as evidenced by reduced serum levels of T and increased E₂ and FSH levels. In addition, SGD effectively reduced the phosphorylation of NF-κB p65 and increased the expression of IκB. Results of the present study demonstrated that SGD could ameliorate hyperandrogenism in PCOS rats, and the potential mechanism may relate to the NF-κB pathway.

Dihydroisocoumarins from Radix Glycyrrhizae

BACKGROUND

Radix Glycyrrhizae is the rhizome of Glycyrrhiza inflata Bat., Glycyrrhiza uralensis Fisch. or Glycyrrhiza glabra L. The present paper describes the isolation and the structural elucidation of three new dihydroisocoumarins obtained from the 70% EtOH extract of Radix Glycyrrhizae. And the cytotoxic activities of these new compounds were also evaluated using four cell lines, subsequently.

RESULTS

A pair of new dihydroisocoumarin epimers ((3R,4S)-4,8-dihydroxy-3-methyl-1-oxoisochroman-5-yl)methyl acetate (1) and ((3R,4R)-4,8-dihydroxy-3-methyl-1-oxoisochroman-5-yl)methyl acetate (2) along with a new dihydroisocoumarin (3R,4R)-4,8-dihydroxy-3,5-dimethylisochroman-1-one (3) were isolated from Radix Glycyrrhizae. Their structures were elucidated on the basis of chemical and spectral analysis, including 1D, 2D NMR analyses, HR-ESI-MSand ECD calculation comparing with those of experimental CD spectra. Cytotoxic activities of the three compounds were evaluated using the HepG2, A549, LoVo and Hela cell lines, respectively. IC₅₀ values indicated compounds 1-3 exhibited moderate or less cytotoxic activity in vitro.

CONCLUSIONS

Dihydroisocoumarin is not the common components in Radix Glycyrrhizae, a series of dihydroisocoumarin were obtained in this plant could be a supplement to the chemical study of this plant.

Identification of metabolites of liquiritin in rats by UHPLC-Q-TOF-MS/MS: metabolic profiling and pathway comparisonin vitroandin vivo

Liquiritin (LQ), the main bioactive constituent of licorice, is a common flavoring and sweetening agent in food products and has a wide range of pharmacological properties, including antidepressant-like, neuroprotective, anti-cancer and anti-inflammatory properties. This study investigated the metabolic pathways of LQ in vitro (rat liver microsomes) and in vivo (rat model) using ultra high-performance liquid chromatography coupled with hybrid triple quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS/MS). Moreover, supplementary tools such as key product ions (KPIs) were employed to search for and identify compounds. As a result, 56 in vivo metabolites and 15 in vitro metabolites were structurally characterized. Oxidation, reduction, hydrolysis, methylation, acetylation, and sulfate and glucuronide conjugation were determined to be the major metabolic pathways of LQ, and there were differences in LQ metabolism in vitro and in vivo. In addition, the in vitro and in vivo metabolic pathways were compared in this study.

Liquiritin (LQ), the main bioactive constituent of licorice, is a common flavoring and sweetening agent in food products and has a wide range of pharmacological properties, including antidepressant-like, neuroprotective and anti-cancer properties.

Economic Importance

The beneficial effects of liquorice in treating chills, colds, and coughs have been fully discussed in Ayurveda, as well as in the texts of ancient Egyptians, Greeks, and Romans. The plant has been prescribed for dropsy during the period of famous Hippocrates. The reason being that it was quite helpful as thirst-quenching drugs (Biondi et al. in J Nat Prod 68:1099–1102, 2005; Mamedov and Egamberdieva in Herbals and human health-phytochemistry. Springer Nature Publishers, 41 pp, 2017). No doubt, the clinical use of liquorice in modern medicine started around 1930; Pedanios Dioscorides of Anazarba (Adana), first century AD-Father of Pharmacists, mentions that it is highly effective in the treatment of stomach and intestinal ulcers. In Ayurveda, people in ancient Hindu culture have used it for improving sexual vigor.

Effects of Active Components of Fuzi and Gancao Compatibility on Bax, Bcl-2, and Caspase-3 in Chronic Heart Failure Rats

Hypaconitine (HA) and glycyrrhetinic acid (GA) are active components of Fuzi (Aconitum carmichaelii) and Gancao (Glycyrrhiza uralensis Fisch); they have been used in compatibility for chronic heart failure (CHF) from ancient times. The purpose of the present research was to explore whether apoptosis pathways were related with the protective effects of HA + GA against CHF rats or not. The rats were progressed with transverse-aortic constriction (TAC) operation for 4 weeks to build the CHF state, and then the Digoxin (1 mg/kg), HA (2.07 mg/kg), GA (25 mg/kg), and HA (2.07 mg/kg) + GA (25 mg/kg) were orally administrated to rats for 1 week. The levels of BNP and cTnI in the plasma were decreased in the HA + GA group, and the heart/body weight ratio (H/B) and left ventricular (LV) parameters of transthoracic echocardiography were also declined; moreover, the expressions of Bax, Bcl-2, and caspase-3 were all improved in the HA + GA group than other groups in the immunohistochemistry and western blot methods. In general, the data suggested that Fuzi and Gancao compatibility could protect the CHF rats from apoptosis, which provided a strong evidence for further searching for mechanisms of them.

Identification and Chemical Standardization of Licorice Raw Materials and Dietary Supplements Using UHPLC-MS/MS

Defined as the roots and underground stems of principally three Glycyrrhiza species, Glycyrrhiza glabra L., Glycyrrhiza uralensis Fish. ex DC., and Glycyrrhiza inflata Batalin, licorice has been used as a medicinal herb for millennia and is marketed as root sticks, powders, and extracts. Identity tests described in most pharmacopeial monographs enabled the distinction of Glycyrrhiza species. Accordingly, an ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) assay using the method of standard addition was developed to quantify 14 licorice components (liquiritin, isoliquiritin, liquiritin apioside, isoliquiritin apioside, licuraside, liquiritigenin, isoliquiritigenin, glycyrrhizin, glycyrrhetinic acid, glabridin, glycycoumarin, licoricidin, licochalcone A, and p-hydroxybenzylmalonic acid), representing several natural product classes including chalcones, flavanones, saponins, and isoflavonoids. Using this approach, G. glabra, G. uralensis, and G. inflata in a variety of forms including root powders and extracts as well as complex dietary supplements could be differentiated and chemically standardized without concerns due to matrix effects.

Kampo Medicine: Evaluation of the Pharmacological Activity of 121 Herbal Drugs on GABAA and 5-HT3A Receptors

Kampo medicine is a form of Japanese phytotherapy originating from traditional Chinese medicine (TCM). During the last several decades, much attention has been paid to the pharmacological effects of these medical plants and their constituents. However, in many cases, a systematic screening of Kampo remedies to determine pharmacologically relevant targets is still lacking. In this study, a broad screening of Kampo remedies was performed to look for pharmacologically relevant 5-HT_3A and GABA_A receptor ligands. Several of the Kampo remedies are currently used for symptoms such as nausea, emesis, gastrointestinal motility disorders, anxiety, restlessness, or insomnia. Therefore, the pharmacological effects of 121 herbal drugs from Kampo medicine were analyzed as ethanol tinctures on heterologously expressed 5-HT_3A and GABA_A receptors, due to the involvement of these receptors in such pathophysiological processes. The tinctures of Lindera aggregata (radix) and Leonurus japonicus (herba) were the most effective inhibitory compounds on the 5-HT_3A receptor. Further investigation of known ingredients in these compounds led to the identification of leonurine from Leonurus as a new natural 5-HT_3A receptor antagonist. Several potentiating herbs (e.g., Magnolia officinalis (cortex), Syzygium aromaticum (flos), and Panax ginseng (radix)) were also identified for the GABA_A receptor, which are all traditionally used for their sedative or anxiolytic effects. A variety of tinctures with antagonistic effects Salvia miltiorrhiza (radix) were also detected. Therefore, this study reveals new insights into the pharmacological action of a broad spectrum of herbal drugs from Kampo, allowing for a better understanding of their physiological effects and clinical applications.

Chromatographic Profiling of Ellagic Acid in Woodfordia fruticosa Flowers and their Gastroprotective Potential in Ethanol-induced Ulcers in Rats

BACKGROUND

Woodfordia fruticosa, a plant of Indian origin, is extensively used in folk medicine for the treatment of various ailments.

OBJECTIVE

The aim of the present study was to standardize the flowers of W. fruticosa, Kurz (Lythraceae), an important plant of Indian origin and explore the chemical constituents contributing to its anti-ulcer activity.

MATERIALS AND METHODS

High-performance thin layer chromatography (HPTLC) and high-performance liquid chromatography (HPLC) profiling of the three samples of W. fruticosa flowers purchased from three different markets was done using ellagic acid as the biomarker. Two doses of the aqueous extract of the W. fruticosa (AEWF) flowers were evaluated for anti-ulcer activity by ethanol-induced ulcer model in Wistar albino rats. Omeprazole was used as the positive control. The parameters used for the assessment of the anti-ulcer potential were total titratable acidity (TTA), ulcer index, and percentage protection.

RESULTS

The HPTLC and HPLC studies confirmed the presence of ellagic acid in all the three drug samples. The AEWF showed significant reduction in terms of TTA at both doses of 100 mg/kg and 200 mg/kg. The gastroprotection indicated by a lower ulcer index and higher percentage protection was significant for 200 mg/kg dose of AEWF, better than the protection afforded by omeprazole (10 mg/kg).

CONCLUSION

The chromatographic profiling and the anti-ulcer studies served as an efficient tool in the characterization of ellagic acid as an important biomarker for the flowers of W. fruticosa and a probable contributor to the gastroprotective capacity of the drug. The bioactivity studies further supported the traditional use of W. fruticosa in the treatment of ulcers.

SUMMARY

HPTLC & HPLC fingerprinting of W. fruticosa using ellagic acid as a biomarker.Evaluation of W. fruticosa for gastroprotection potential in ethanol induced gastric ulcer in rats model.Aqueous extract of the drug showed better gastroprotection than the standard drug omeprazole at a dose of 200 mg/kg.

Glycyrrhiza glabra

Liquorice foliage

Metabolite Profiling and Classification of DNA-Authenticated Licorice Botanicals

Raw licorice roots represent heterogeneous materials obtained from mainly three Glycyrrhiza species. G. glabra, G. uralensis, and G. inflata exhibit marked metabolite differences in terms of flavanones (Fs), chalcones (Cs), and other phenolic constituents. The principal objective of this work was to develop complementary chemometric models for the metabolite profiling, classification, and quality control of authenticated licorice. A total of 51 commercial and macroscopically verified samples were DNA authenticated. Principal component analysis and canonical discriminant analysis were performed on (1)H NMR spectra and area under the curve values obtained from UHPLC-UV chromatograms, respectively. The developed chemometric models enable the identification and classification of Glycyrrhiza species according to their composition in major Fs, Cs, and species specific phenolic compounds. Further key outcomes demonstrated that DNA authentication combined with chemometric analyses enabled the characterization of mixtures, hybrids, and species outliers. This study provides a new foundation for the botanical and chemical authentication, classification, and metabolomic characterization of crude licorice botanicals and derived materials. Collectively, the proposed methods offer a comprehensive approach for the quality control of licorice as one of the most widely used botanical dietary supplements.

Identification of Glycyrrhiza as the rikkunshito constituent with the highest antagonistic potential on heterologously expressed 5-HT3A receptors due to the action of flavonoids

The traditional Japanese phytomedicine rikkunshito is traditionally used for the treatment of gastrointestinal motility disorders, cachexia and nausea. These effects indicate 5-HT₃ receptor antagonism, due to the involvement of these receptors in such pathophysiological processes. E.g., setrons, specific 5-HT₃ receptor antagonists are the strongest antiemetics, developed so far. Therefore, the antagonistic effects of the eight rikkunshito constituents at heterologously expressed 5-HT_3Areceptors were analyzed using the two-electrode voltage-clamp technique. The results indicate that tinctures from Aurantii, Ginseng, Zingiberis, Atractylodis and Glycyrrhiza inhibited the 5-HT_3A receptor response, whereas the tinctures of Poria cocos, Jujubae and Pinellia exhibited no effect. Surprisingly, the strongest antagonism was found for Glycyrrhiza, whereas the Zingiberis tincture, which is considered to be primarily responsible for the effect of rikkunshito, exhibited the weakest antagonism of 5-HT_3A receptors. Rikkunshito contains various vanilloids, ginsenosides and flavonoids, a portion of which show an antagonistic effect on 5-HT₃ receptors. A screening of the established ingredients of the active rikkunshito constituents and related substances lead to the identification of new antagonists within the class of flavonoids. The flavonoids (-)-liquiritigenin, glabridin and licochalcone A from Glycyrrhiza species were found to be the most effective inhibitors of the 5-HT-induced currents in the screening. The flavonoids (-)-liquiritigenin and hesperetin from Aurantii inhibited the receptor response in a non-competitive manner, whereas glabridin and licochalcone A exhibited a potential competitive antagonism. Furthermore, licochalcone A acts as a partial antagonist of 5-HT_3A receptors. Thus, this study reveals new 5-HT_3A receptor antagonists with the aid of increasing the comprehension of the complex effects of rikkunshito.

Simultaneous determination and assignment of 13 major flavonoids and glycyrrhizic acid in licorices by HPLC-DAD and Orbirap mass spectrometry analyses

To determine 13 flavonoids and glycyrrhizic acid in licorice (Glycyrrhiza spp.), several samples from different areas were examined by HPLC-DAD analysis. The analysis was performed on a Zorbax Extend-C18 (250 mm × 4.6 mm, 5 μm) column connected with a Zorbax Extend guard column (20 mm × 4.6 mm, 5 μm). The mobile phase consisted of (A) acetonitrile and (B) 0.026% aqueous H3PO4 (VV) using a gradient elution of 20%-25% A at 0-20 min, 25%-33% A at 20-30 min, 33%-50% A at 30-55 min, 50%-60% A at 55-65 min, and 60% A between 65 min and 80 min, and peaks were detected at 280 nm. The fourteen compounds were assigned by HPLC-Orbitrap MS methods. The regression coefficient for the linear equations for the 14 compounds ranged between 0.9998 and 1. The limits of detection and quantification lay in the range of 0.032-2.461 and 0.154-8.202 μg·mL(1), respectively. The relative recovery rates for the 14 compounds were in the range of 93.90%-106.73% with RSDs being less than 5%. Coefficient variations for intra-day and inter-day precisions were in the range of 0.27%-2.38% and 0.31%-3.51%, respectively. In summary, the validated method was applied to the simultaneous determination of the 14 components in 29 different licorice samples and was proven to be suitable for quality evaluation of licorices and their active fractions.

A simple semi-preparative reversed-phase HPLC/PDA method for separation and quantification of glycyrrhizin in nine samples of Glycyrrhiza glabra root collected from different geographical origins

INTRODUCTION

Glycyrrhiza glabra L. (Fabaceae), commonly known as 'liquorice', is one of the most popular ingredients in several traditional herbal medicinal preparations, and glycyrrhizin is the major glycoside present in this plant. The content of glycyrrhizin may vary among G. glabra samples collected from various geographical origins, which may affect the therapeutic efficacy. Thus, quantification of glycyrrhizin in G. glabra samples is important.

OBJECTIVE

To develop and validate a simple semi-preparative reversed-phase HPLC with photodiode array (PDA) method for separation and quantification of glycyrrhizin in nine samples of G. glabra root collected from various geographical origins.

METHODS

Dried and ground root of G. glabra was Soxhlet-extracted sequentially with n-hexane and methanol (MeOH). The separation and quantification of glycyrrhizin was achieved on a C18 reversed-phase semi-preparative column using a gradient mobile phase, 30-100% solvent B in solvent A in 30 min (solvent A: 0.1% v/v trifluoroacetic acid (TFA) in water and solvent B: 0.1% v/v of TFA in MeOH), at a flow rate of 3.00 mL/min and UV detection at 254 nm.

RESULTS

A simple semi-preparative reversed-phase HPLC/PDA method allowing clear separation and quantification of glycyrrhizin content in nine samples has been validated in terms of linearity, selectivity, limits of detection, precision, accuracy and detection. Concentration levels of glycyrrhizin were between 0.177 and 0.688% w/w of dry materials.

CONCLUSION

This method is precise, less time consuming and more cost effective, and can be used for the quality control of any G. glabra sample with regard to its glycyrrhizin contents.

Species-specific Standardisation of Licorice by Metabolomic Profiling of Flavanones and Chalcones

INTRODUCTION

Major phenolics from licorice roots (Glycyrrhiza sp.) are glycosides of the flavanone liquiritigenin (F) and its 2′-hydroxychalcone isomer, isoliquiritigenin (C). As the F and C contents fluctuate between batches of licorice, both quality control and standardisation of its preparations become complex tasks.

OBJECTIVE

To characterise the F and C metabolome in extracts from Glycyrrhiza glabra L. and Glycyrrhiza uralensis Fisch. ex DC. by addressing their composition in major F–C pairs and defining the total F:C proportion.

MATERIAL AND METHODS

Three types of extracts from DNA-authenticated samples were analysed by a validated UHPLC/UV method to quantify major F and C glycosides. Each extract was characterised by the identity of major F–C pairs and the proportion of Fs among all quantified Fs:Cs.

RESULTS

The F and C compositions and proportions were found to be constant for all extracts from a Glycyrrhiza species. All G. uralensis extracts contained up to 2.5 more Fs than G. glabra extracts. Major F–C pairs were B-ring glycosidated in G. uralensis, and A-/B-ring apiosyl-glucosidated in the G. glabra extracts. The F:C proportion was found to be linked to the glycosidation site: the more B-ring F-C glycosides were present, the higher was the final F:C proportion in the extract. These results enable the chemical differentiation of extracts from G. uralensis and G. glabra, which are characterised by total F:C proportions of 8.37:1.63 and 7.18:2.82, respectively.

CONCLUSION

Extracts from G. glabra and G. uralensis can be differentiated by their respective F and C compositions and proportions, which are both useful for further standardisation of licorice botanicals.

18β-glycyrrhetinic acid attenuates anandamide-induced adiposity and high-fat diet induced obesity

SCOPE

Previous reports suggest that licorice extract has various metabolically beneficial effects and may help to alleviate adiposity and hyperlipidemia. However, underlying anti-obesity mechanisms still remain elusive. Moreover, it is unknown which single ingredient in licorice extract would mediate such effects. We aimed to demonstrate that licorice extract and its active ingredients can inhibit adipocyte differentiation and fat accumulation.

METHODS AND RESULTS

18β-glycyrrhetinic acid (18β-GA) alleviated the effects of CB1R agonist, anandamide (AEA) on CB1R signaling in a concentration-dependent manner. Consistently, 18β-GA suppressed AEA-induced adipocyte differentiation in 3T3-L1 cells through the downregulation of AEA-induced MAPK activation and expression of adipogenic genes including C/EBP-α and PPAR-γ. The protein levels of fatty acid synthase and stearoyl-CoA desaturase 1 were also decreased and the phosphorylation of acetyl-CoA carboxylase was increased in 18β-GA pretreated cells. The supplementation of 18β-GA significantly lowered body weight, fat weight, and plasma lipids levels in obese animal models.

CONCLUSION

These results may provide a novel insight into the molecular mechanism involved in anti-adipogenic and anti-obesity effects of 18β-GA by suppressing the activation of CB1R induced by AEA. Thus, 18β-GA may exert beneficial effects against obesity-related metabolic disorders.

In vitro studies on protective effect of Glycyrrhiza glabra root extracts against cadmium-induced genetic and oxidative damage in human lymphocytes

Cadmium is a modern environmental contaminant that is toxic and carcinogenic. Glycyrrhiza glabra is a traditional medicinal herb which grows in the various parts of the World. Recent studies demonstrated that G. glabra has antifungal, antimicrobial, antioxidant, and powerful antiinflammatory features. The purpose of this study was to investigate the genetic safety of extracts from G. glabra and its effects on cadmium (as CdCl2) induced genotoxicity. Therefore we evaluated the capability of G. glabra extract to inhibit the rate of micronucleus (MN), sister chromatid exchange (SCE) formations induced by CdCl2. Moreover, to assess the effects of G. glabra on cell viability and oxidative status, we performed 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and total antioxidant capacity (TAC) assays. Our results showed that there were significant increases (P < 0.05) in both SCE and MN frequencies of cultures treated with CdCl2 (5 ppm) as compared to controls. However, co-application of G. glabra extract (5, 10 and 20 ppm) and CdCl2 resulted in decreases of MN and SCE rates as compared to the group treated with CdCl2 alone. Again, the results of MTT and TAC assays clearly indicated dose dependent ameliorative effects of G. glabra extracts against CdCl2 toxicity. In conclusion, this study demonstrated for the first time that G. glabra extracts provided increased resistance of DNA against CdCl2 induced genetic and oxidative damage in human lymphocytes. So, the risk on target tissues of CdCl2 could be reduced and ensured early recovery from its toxicity.

Deciphering the combination principles of Traditional Chinese Medicine from a systems pharmacology perspective based on Ma-huang Decoction

ETHNOPHARMACOLOGY RELEVANCE

The main therapeutic concept in Traditional Chinese Medicine (TCM) is herb formula, which treats various diseases via potential herb interactions to maximize the efficacy and minimize the adverse effects. However, the combination principle of herb formula still remains a mystery due to the lack of appropriate methods.

METHODS

A systems pharmacology method integrating the pharmacokinetic analysis, drug targeting, and drug-target-disease network is developed to dissect this rule embedded in the herbal formula. All these are exemplified by a representative TCM formula, Ma-huang decoction, made up of four botanic herbs.

RESULTS

Based on the deep investigation of the function and compatibility of each herb, in a molecular/systems level, we demonstrate the different pharmacological roles that each herb might play in the prescription. By the way of enhancing the bioavailability and/or making the pharmacological synergy among different herbs, the four herbs effectively combine together to be suitable for treating diseases.

CONCLUSIONS

The present work lays foundations for a more comprehensive understanding of the combination rule of TCM, which might also be beneficial to drug development and applications.

Field-amplified sample stacking β-cyclodextrin modified capillary electrophoresis for quantitative determination of diastereomeric saponins

Successful simultaneous diastereomeric separation and sensitive determination of two pairs of triterpenoidal saponins have been achieved by capillary electrophoresis (CE) using β-cyclodextrin (β-CD) as a stereoselective agent to cooperate with borate complexation. A usual technique for isolation and group separation of saponins was developed as an appropriate purification step prior to the determination of individual saponins by CE. Soyasaponin I ( S1: ), azukisaponin V ( S2: ), bersimoside I ( S3: ) and bersimoside II ( S4: ) could be well separated within 14 min in a fused-silica capillary (60 cm long to the detector with an additional 10 cm to the cathode; 75 µm i.d.). The background electrolyte was borate buffer (80 mM, pH 10), containing 24 mM β-CD. The separation voltage was 14 kV with a detection wavelength of 195 nm. The sample was electrokinetically injected using a voltage of 16 kV for 12 s. Methanol (70%) was used as the diluent for field-amplified sample stacking after hydrodynamic injection of short water plug (5 cm, 4 s). The method was partially validated for linearity, repeatability, reproducibility, limits of detection and limits of quantification. The correlation coefficients of the calibration curves were all >0.998, and the recoveries were from 98.23 to 96.21%.

Toxicity of ochratoxin a and its modulation by antioxidants: a review

Ochratoxin A (OTA) is a mycotoxin involved in the development of different types of cancers in rats, mice and humans. A growing number of in vitro and in vivo studies has been collected and has described evidence compatible with a role for oxidative stress in OTA toxicity and carcinogenicity. Because the contribution of the oxidative stress response in the development of cancers is well established, a role in OTA carcinogenicity is plausible. Several studies have been performed to try to counteract the adverse effects of oxygen radicals generated under OTA-exposure. A number of molecules with various antioxidant properties were tested, using in vivo or in vitro models. Protection against OTA-induced DNA damage, lipid peroxidation, as well as cytotoxicity were observed, further confirming the link between OTA toxicity and oxidative damage. These studies demonstrated that antioxidants are able to counteract the deleterious effects of chronic consumption or exposure to OTA and confirmed the potential effectiveness of dietary strategies to counteract OTA toxicity.

Water extract of licorice had anti-viral activity against human respiratory syncytial virus in human respiratory tract cell lines

ETHNOPHARMACOLOGICAL RELEVANCE

Licorice (Glycyrrhiza uralensis Fisch., Leguminosae) has been used in herbal medicine and food supplement worldwide for centuries. Licorice is a common ingredient of several prescriptions of traditional Chinese medicine which have been proved to inhibit infection of human respiratory syncytial virus (HRSV). There are two preparations of licorice, Radix Glycyrrhizae and Radix Glycyrrhizae Preparata. However, it is unknown whether licorice or which preparation of licorice is effective against HRSV, nor is its active constituent.

AIM OF THE STUDY

We tested the hypothesis that Radix Glycyrrhizae can effectively decrease HRSV-induced plaque formation in respiratory mucosal cell lines. We also tried to find out the active constituent.

MATERIALS AND METHODS

Anti-HRSV activities of hot water extracts of preparations of licorice, glycyrrhizin and 18β-glycyrrhetinic acid (18β-GA), the active constituents of licorice, were examined by plaque reduction assay in both human upper (HEp-2) and low (A549) respiratory tract cell lines. Abilities of crude licorice to inhibit viral replication and to stimulate IFN-β were evaluated by reverse transcription polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA), respectively.

RESULTS

Radix Glycyrrhizae and Radix Glycyrrhizae Preparata dose-dependently inhibited HRSV-induced plaque formation in both HEp-2 and A549 cell lines (p<0.0001). The effect of Radix Glycyrrhizae was better than that of Radix Glycyrrhizae Preparata on HEp-2 cells. However, there was no difference of their anti-HRSV effects on A549 cells. Besides, glycyrrhizin was ineffective at all. Nevertheless, 18β-GA showed a potent anti-HRSV activity. Radix Glycyrrhizae was more effective when given before viral inoculation (p<0.0001) which may be due to its inhibition of viral attachment on (p<0.0001) and penetration (p<0.0001) into the host cells. The anti-HRSV activity of Radix Glycyrrhizae was further confirmed by RT-PCR and qRT-PCR. 300 μg/ml Radix Glycyrrhizae markedly decreased the viral amounts within the cells and in the suspension. Radix Glycyrrhizae might further stimulate mucosal cells to secrete IFN-β to counteract viral infection.

CONCLUSIONS

Both Radix Glycyrrhizae and Radix Glycyrrhizae Preparata are effective against HRSV infection on airway epithelial cells. Radix Glycyrrhizae inhibited HRSV mainly by preventing viral attachment, internalization, and by stimulating IFN secretion. 18β-GA may be one of its active constituents.

Factors Influencing Glabridin Stability

Glabridin, a polyphenolic isoflavan of Glycyrrhiza glabra, has shown a variety of pharmaceutical properties. We have previously studied the isolation of glabridin using macroporous resin and found that it is partially degraded, giving a dark color. To illustrate the degradation of glabridin, the present work studied the stability of glabridin under various conditions. Licorice extract containing about 20% glabridin, obtained from G. glabra by silica gel column chromatography, was used in the stability study. Seven different factors (temperature, illumination, humidity, pH, solvent, oxygen, and oxidant) were studied and content changes were determined through HPLC analysis. Except for oxygen, all the above factors had an effect on the stability of glabridin, with illumination being the main one. Moreover, the interactions between temperature and pH, temperature and humidity, and illumination and pH can promote the degradation of glabridin. In conclusion, we suggest that a dark, dry and airtight environment provides the optimized condition for the long-term storage of glabridin.

Structural characterization and identification of oleanane-type triterpene saponins in Glycyrrhiza uralensis Fischer by rapid-resolution liquid chromatography coupled with time-of-flight mass spectrometry

Oleanane-type triterpene saponins (OTS) are major active ingredients in Glycyrrhiza uralensis. In this work, a rapid-resolution liquid chromatography with time-of-flight mass spectrometry (RRLC/TOF-MS) method has been developed to characterize and identify OTS from G. uralensis. The major diagnostic ions and fragmentation pathways from thirteen OTS have been characterized for the first time. At a low fragmentor voltage of 120  V in positive ion mode, the precursor ion [M + H](+) or/and [M + Na](+) was obtained for accurate determination of molecular formula. When the fragmentor voltage was increased to 425  V, abundant characteristic fragment ions were observed for structural characterization. Neutral losses of sugar moieties, such as glucuronic acid (GlcA, 176  Da), glucose (Glc, 162  Da) and rhamnose (Rha, 146 Da), were commonly observed in the MS spectra for prediction of the sugar number and sequences. Other typical losses included AcOH (60  Da), CH(2)O (30  Da), 2 × H(2)O (2 × 18  Da) and HCOOH (46  Da) from [Aglycone + H-H(2)O](+) (named [B](+)), corresponding to the presence of a C(22)-acetyl group, C(24)-hydroxyl group, C(22)-hydroxyl group or C(30)-carboxyl group on the aglycone moiety, respectively. In particular, characteristic ring cleavages of the aglycone moieties on A- and B-rings were observed. Based on the fragmentation patterns of reference compounds, nineteen OTS have been identified in an extract of G. uralensis, thirteen of which were unambiguously identified and the other six were tentatively assigned.

Protective effects of melatonin and Glycyrrhiza glabra extract on ochratoxin A--induced damages on testes in mature rats

The effect of Glycyrrhiza glabra extract (GgE) as a natural antioxidant and melatonin (MEL) on ochratoxin A (OTA)-induced histopathological damages on the testes and oxidative stress was evaluated in male rats. The animals were assigned into four groups (n = 8) including control and test groups. The rats in control group received saline and the animals in the test groups received (200 µg/kg) of OTA, (15 mg/kg) of MEL + (200 µg/kg) OTA and (100 mg/kg) of GgE + (200 µg/kg) OTA, respectively, during 28 consecutive days. The serum total antioxidant power (TAOP) and total thiol molecules (TTM) production were assessed. Moreover, histopathological and histochemical studies were also performed. The results showed that the TAOP and TTM were decreased in OTA-exposed rats, while the animals that received MEL + OTA or GgE + OTA showed an enhancement in the serum TAOP and TTM levels. Histopathological analyses demonstrated that in OTA-exposed rats, the testicular degeneration, seminiferous tubule atrophy, dissociation of germinative epithelium, vasodilatation with vascular thrombosis, perivascular immune cell infiltration, hypertrophied leydic cells, giant cell formation, and negative tubular differentiation index (TDI) were observed. Surprisingly, both the biochemical and histopathological examinations showed that MEL and GgE, albeit with some differences, exerted a protective effect on OTA-induced damages. In conclusion, this data suggest that OTA contamination in animal feeds and human foods could cause reproductive abnormalities. Our data also indicate that OTA, at least partly by interfering in oxidative stress system, exerts its toxic effects on testes whereas MEL and GgE with antioxidant properties could fairly protect rats against OTA toxic effects.