Roots Of Glycyrrhiza Uralensis Research Articles

Ochrobactrum endophyticum sp. nov., isolated from roots of Glycyrrhiza uralensis.

A novel Gram-staining negative, motile, rod-shaped and aerobic bacterial strain, designated EGI 60010(T), was isolated from healthy roots of Glycyrrhiza uralensis F. collected from Yili County, Xinjiang Province, North-West China. The 16S rRNA gene sequence of strain EGI 60010(T) showed 97.2 % sequence similarities with Ochrobactrum anthropi ATCC 49188(T) and Ochrobactrum cytisi ESC1(T), and 97.1 % with Ochrobactrum lupini LUP21(T). The phylogenetic analysis based on 16S rRNA gene sequences showed that the new isolate clustered with members of the genera Ochrobactrum, and formed a distinct clade in the neighbour-joining tree. Q-10 was identified as the respiratory quinone for strain EGI 60010(T). The major fatty acids were summed feature 8 (C18:1 ω6c and/or C18:1 ω7c), C19:0 cyclo ω8c, summed feature 4 (C17:1 iso I/anteiso B) and C16:0. The polar lipids detected were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylmethylethanolamine, phosphatidylglycerol and phosphatidylcholine. The DNA G+C content of strain EGI 60010(T) was determined to be 60.4 mol%. The genomic DNA relatedness values determined between strain EGI 60010(T) and the closely related strains O. anthropi JCM 21032(T), O. cytisi CCTCC AB2014258(T) and O. lupini NBRC 102587(T) were 50.3, 50.0 and 41.6 %, respectively. Based on the results of the molecular studies supported by its differentiating phenotypic characteristics, strain EGI 60010(T) was considered to represent a novel species within the genus Ochrobactrum, for which the name Ochrobactrum endophyticum sp. nov., is proposed. The type strain is EGI 60010(T) (=CGMCC 1.15082(T) = KCTC 42485(T) = DSM 29930(T)).

Novosphingobium endophyticum sp. nov. isolated from roots of Glycyrrhiza uralensis

A novel Gram-staining-negative, non-motile, rod-shaped and aerobic bacterial strain, designated EGI 60015(T), was isolated from healthy roots of Glycyrrhiza uralensis F. collected from Yili County, Xinjiang Province, Northwest China. The 16S rRNA gene sequence of strain EGI 60015(T) was found to show 97.6% sequence similarity with Novosphingobium pentaromativorans US6-1(T). The phylogenetic analysis based on 16S rRNA gene sequences showed that the strain formed a clade with N. pentaromativorans US6-1(T) in the neighbor-joining tree. Q-10 was identified as the respiratory quinone of strain EGI 60015(T). The major fatty acids were summed feature 8 (C18:1 ω6c and/or C18:1 ω7c; 55.04%), summed feature 4 (C17:1 anteiso B and/or iso I; 18.34%) and summed feature 3 (C16:1 ω6c and/or C16:1 ω7c; 8.53%). The polar lipids detected were phosphatidylethanolamine, phosphatidylmethylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylcholine and sphingoglycolipids. The DNA G+C content of strain EGI 60015(T) was determined to be 66.6 mol%. The genomic DNA relatedness value between EGI 60015(T) and N. pentaromativorans US6-1(T) (54%) was below the 70% limit for species identification. Based on the result of the molecular studies supported by its morphological, physiological, chemotaxonomic and other differentiating phenotypic characteristics, strain EGI 60015(T) was considered to represent a novel species within the genus Novosphingobium, for which the name Novosphingobium endophyticum sp. nov. is proposed. The type strain is EGI 60015(T) (=CGMCC 1.15095(T) = KCTC 42486(T) = DSM 29948(T)).

Salicylic acid induces the change in the adventitious root of Glycyrrhiza uralensis Fisch.: bioactive compounds and antioxidant enzymes

In this study, adventitious roots of Glycyrrhiza uralensis were cultured in a 5-L balloon-type bubble bioreactor with different medium salt strength and different concentrations of sucrose. The results of the culture showed that the best culture conditions were 4 % sucrose concentration and 1 MS medium for the accumulation of secondary metabolites. Salicylic acid has previously been used as an elicitor in tissue cultures to enhance production of secondary metabolites. Addition of 1 mg L−1 salicylic acid significantly enhanced the contents of glycyrrhizic acid (0.31 mg g−1), glycyrrhetinic acid (0.14 mg g−1) and polysaccharide (159.29 mg g−1) in the G. uralensis adventitious roots and the contents were 2.58-fold, 1.27-fold, and 2.07-fold over the control group. Furthermore, the greatest content of total flavonoid (9.40 mg g−1) was observed with 2 mg L−1 salicylic acid added in the culture, which was 2.68-fold higher than the control. The ESI-MSn analysis was also performed, showing that two new kinds of flavonoids, including (3R)-vestitol and glycyrol, were only identified in the salicylic acid treatment. In addition, we also found that salicylic acid significantly increased superoxide dismutases, catalases, and peroxidase activity.

Separation and characterization of phenolic compounds and triterpenoid saponins in licorice (Glycyrrhiza uralensis) using mobile phase-dependent reversed-phase × reversed-phase comprehensive two-dimensional liquid chromatography coupled with mass spectrometry

Licorice is one of the most popular herbal medicines worldwide. It contains a big array of phenolic compounds (flavonoids, coumarins, and diphenylethanones). Due to high structural diversity, low abundance, and co-elution with licorice saponins, these phenolic compounds are difficult to be separated by conventional chromatography. In this study, a mobile phase-dependent reversed-phase×reversed phase comprehensive two-dimensional liquid chromatography (RP×RP 2DLC) method was established to separate phenolic compounds in licorice (the roots of Glycyrrhiza uralensis). Organic solvents in the mobile phase were optimized to improve orthogonality of the first and second dimensions, and a synchronized gradient mode was used to improve chromatographic resolution. Finally, licorice extracts were eluted with methanol/water/formic acid in the first dimension (Acquity CSH C18 column), and acetonitrile/water/formic acid in the second dimension (Poroshell Phenyl-Hexyl column). By using this 2DLC system, a total of 311 compounds were detected within 40min. The practical and effective peak capacity was 1329 and 524, respectively, and the orthogonality was 79.8%. The structures of 21 selected unknown compounds were tentatively characterized by mass spectrometry, and 8 of them were discovered from G. uralensis for the first time. The mobile phase-dependent 2DLC/MS system could benefit the separation and characterization of natural products in complicated herbal extracts.

Quercetin-induced apoptosis prevents EBV infection.

Epstein-Barr virus (EBV) is a human gamma-1 herpesvirus that establishes a lifelong latency in over 90% of the world's population. During latency, virus exists predominantly as a chromatin-associated, multicopy episome in the nuclei of a variety of tumor cells derived from B cells, T cells, natural killer (NK) cells, and epithelial cells. Licorice is the root of Glycyrrhiza uralensis or G. glabra that has traditionally cultivated in eastern part of Asia. Licorice was reported to have anti-viral, anti-inflammatory, anti-atopic, hepatoprotective, anti-neurodegenerative, anti-tumor, anti-diabetic effects and so forth. Quercetin and isoliquiritigenin are produced from licorice and highly similar in molecular structure. They have diverse bioactive effects such as antiviral activity, anti-asthmatic activity, anti-cancer activity, anti-inflammation activity, monoamine-oxidase inhibitor, and etc. To determine anti-EBV and anti-EBVaGC (Epstein-Barr virus associated gastric carcinoma) effects of licorice, we investigated antitumor and antiviral effects of quercetin and isoliquiritigenin against EBVaGC. Although both quercetin and isoliquiritigenin are cytotoxic to SNU719 cells, quercetin induced more apoptosis in SNU719 cells than isoliquiritigenin, more completely eliminated DNMT1 and DNMT3A expressions than isoliquiritigenin, and more strongly affects the cell cycle progression of SNU719 than isoliquiritigenin. Both quercetin and isoliquiritigenin induce signal transductions to stimulate apoptosis, and induce EBV gene transcription. Quercetin enhances frequency of F promoter use, whereas isoliquiritigenin enhances frequency of Q promoter use. Quercetin reduces EBV latency, whereas isoliquiritigenin increases the latency. Quercetin increases more the EBV progeny production, and inhibits more EBV infection than isoliquiritigenin. These results indicate that quercetin could be a promising candidate for antiviral and antitumor agents against EBV and human gastric carcinoma.

Enantiomeric 3-arylcoumarins and 2-arylcoumarones from the roots of Glycyrrhiza uralensis as protein tyrosine phosphatase 1B (PTP1B) inhibitors

Four new PTP1B inhibitors were isolated from Glycyrrhiza uralensis, and the absolute configuration of 2,3-dihydro-2,3,3-trimethylbenzofurans was first unambiguously established.

The analysis of differential rxpression of glycyrrhiza uralensis root gene by nitrogen ions implantationbased on cDNA-AFLP method

The analysis of differential rxpression of glycyrrhiza uralensis root gene by nitrogen ions implantationbased on cDNA-AFLP method

Two minor chalcone acetylglycosides from the roots extract of Glycyrrhiza uralensis.

An extensive phytochemical investigation on the roots of Glycyrrhiza uralensis led to the isolation of two new minor chalcone acetylglycosides, i.e., 6″-O-acetylisoliquiritin (1) and 6″-O-acetylneoisoliquiritin (2), including 16 kinds of known constituents (3-18) of flavonoids, chalcones and triterpene saponins. The chemical structures of 1 and 2 were established by spectroscopic analyses of them, particularly by the aid of two-dimensional NMR experiments, COSY, DEPT, HSQC and HMBC. Some isolated components except 1 and 2 exhibited significant inhibitory effects on the proliferation of cultured tumor cell lines, such as A549, SK-OV-3, A-498, and HCD15, in vitro.

Compounds in Psoralea corylifolia as human MAOb natural inhibitors (1143.12)

Treatment for Parkinson’s disease (PD) involves the use of drugs that address the loss of dopaminergic function by restoring neurotransmitter homeostasis. However, the current drugs can be limiting, in that they do not address disease progression. A renewed interest in monoamine oxidase B inhibitors (MAObIs) for PD as independent therapeutics has emerged after recent clinical trials has shown efficacy of deprenyl and rasagiline monotherapy for early disease management. However, conventional MAOIs have food and drug counter‐interactions and side effects which limit its use. Previously, we screened 905 natural ethanol plant extracts on the enzymatic activity of recombinant human MAOb. In this study, we confirm and determine selectivity of MAOb / MAOa. The data show that extracts of Glycyrrhiza uralensis root have an IC50 of 0.04 mg/ml and a 266 fold MAOb/MAOa specificity; Phellodendron Amurense an IC50 of 0.02 mg/ml and a MAOb/MAOa specificity 45.29 fold; Psoralea Corylifolia (PC) an IC50 of 0.08 mg/ml and a 18.34 fold MAOb/MAOa specificity; Ferula Assa‐Foetida an IC50 of 0.24 mg/ml and a 30.23 fold MAOb/MAOa specificity. Further studies for PC active ingredients revealed that bakuchiol content within the plant may contribute to MAOI.Grant Funding Source: Supported by NIMHD G12 MD007582 and P20 MD006738

Interaction of gypsum and the rhizome of Anemarrhena asphodeloides plays an important role in anti-allergic effects of byakkokakeishito in mice

Gypsum is a crude mineral drug used in the formulas of Japanese kampo medicine and traditional Chinese medicine. The present study aimed to evaluate the anti-allergic effect of byakkokakeishito extract (BKT), which consists of gypsum (natural hydrous calcium sulfate), Anemarrhena Rhizome (rhizome of Anemarrhena asphodeloides), Cinnamon Bark (bark of trunk of Cinnamomum cassia), Oriza Seed (seed of Oryza sativa), and Glycyrrhiza (root and stolon of Glycyrrhiza uralensis), and to clarify the role of gypsum in the formula. We prepared BKT by boiling a mixture of various quantities of gypsum and fixed amounts of the other four crude drugs in water. We evaluated the anti-allergic activity of the formulations using three different murine models of allergy: contact dermatitis induced by painting hapten onto skin; allergic dermatitis-like symptoms induced by cutaneous injection of mite-antigen; and skin passive cutaneous anaphylaxis (PCA) reaction using ovalbumin as antigen. The calcium content in the various BKT samples was dose-dependently increased up to 60 g/day of human dosage. BKT significantly suppressed the allergic symptoms in the three different experimental models. The effect of BKT was augmented by increasing the gypsum dosage only in the PCA reaction model. The extract prepared from a mixture of Anemarrhena Rhizome and gypsum exhibited an effect comparable to that of BKT. BKT exhibits an anti-allergic effect in several animal models, which may provide experimental evidence for the clinical use of BKT in allergic diseases. Gypsum may augment the anti-allergic activity of BKT, presumably through increasing intestinal absorption of Anemarrhena Rhizome-derived active constituents.

Traditional formula, modern application: chinese medicine formula sini tang improves early ventricular remodeling and cardiac function after myocardial infarction in rats.

Sini Tang (SNT) is a traditional Chinese herbal formula consisting of four different herbs: the root of Aconitum carmichaelii, the bark of Cinnamomum cassia, the rhizome of Zingiber officinale, and the root of Glycyrrhiza uralensis. This study aims to evaluate the improvement of early ventricular remodeling and cardiac function in myocardial infarction (MI) rats by SNT. A MI model was established by ligation of the left anterior descending coronary artery. Following treatment for 4 weeks, ultrasonic echocardiography was performed. Myocardial histopathological changes were observed using haematoxylin and eosin staining. Collagens (type I and type III), transforming growth factor-β1 (TGF-β1), and Toll-like receptors (TLR-2 and TLR-4) were measured in plasma, serum, and myocardial tissue. SNT treatment decreased the infarct size, the left ventricular cavity area/heart cavity area ratio, and the left ventricle dimension at end systole and increased the left ventricular ejection fraction. SNT reduced the levels of TLR-2 and TLR-4 in myocardial tissue significantly and decreased the collagens content in serum and in myocardial tissue. SNT could partially reduce the level of TGF-β1 in serum and in myocardial tissue. Our data suggest that the Chinese medicine formula SNT has the potential to improve early ventricular remodeling and cardiac function after MI.

Rapid screening and analysis of alcohol dehydrogenase binders from Glycyrrhiza uralensis root extract using functionalized magnetic nanoparticles coupled with HPLC−MS/MS

Alcohol dehydrogenase (ADH) is a key enzyme that converts ethanol into acetaldehyde. Its binders could be used to efficiently treat human toxic alcohol poisoning and suppress the acetaldehyde accumulation in alcohol hypersensitive alcoholics. In the present study, a new assay based on ADH-functionalized magnetic nanoparticles coupled with high-performance liquid chromatography − tandem mass spectrometry (HPLC−MS/MS) was developed for the rapid screening and identification of ADH binders. ADH was immobilized on silica-coated Fe3O4 magnetic nanoparticles via covalent bonds and the synthesized nanoparticles were characterized by TEM, XRD, FT-IR, and VSM. The amount of bound ADH onto magnetic nanoparticles was 80.6 μg/mg. The optimum temperature and pH for the enzymatic activity of immobilized ADH were 25 °C and 7.0, respectively. The relative activity of immobilized ADH remained 68.14% after 10 times of recycle, which exhibited good durability. Nine compounds with ADH-binding activity were screened and identified in Glycyrrhiza uralensis root extracts, among which seven compounds were first screened and identified. Experimental results proved that the proposed method could rapidly screen ADH binders from complex mixtures.

The Antiinflammatory Mechanism of Igongsan in Mouse Peritoneal Macrophages via Suppression of NF-κB/Caspase-1 Activation

Igongsan (IGS), which is an herbal prescription composed of five different herbs, Ginseng Radix (root of Panax ginseng, Araliaceae), Atractylodis Rhizoma Alba (rhizome of Atractylodes Macrocephala, Compositae), Poria Sclerotium (sclerotium of Poria cocos, Polyporaceae), Glycyrrhizae Radix et Rhizoma (root and rhizome of Glycyrrhiza uralensis, Leguminosae), and Citri Unshius Pericarpium (Peel of Citrus unshiu, Rutaceae), has been traditionally used in Korea to treat a variety of inflammatory diseases. In this study, we investigated to elucidate the mechanism responsible for IGS's antiinflammatory effect in mouse peritoneal macrophages. The findings demonstrate that IGS inhibited the production of inflammatory cytokine and prostaglandins E2 . IGS inhibited the enhanced levels of cyclooxygenase-2 and inducible NO synthase caused by lipopolysaccharide (LPS). Additionally, it was shown that the antiinflammatory effect of IGS is through regulating the activation of nuclear factor-kappa B and caspase-1 in LPS-stimulated mouse peritoneal macrophages. These results provide novel insights into the pharmacological actions of IGS as a potential candidate for development of new drugs to treat inflammatory diseases. These results provide novel insights into the pharmacological actions of IGS as a potential candidate for development of new drugs to treat inflammatory diseases.

Analysis of tyrosinase binders from Glycyrrhiza uralensis root: Evaluation and comparison of tyrosinase immobilized magnetic fishing-HPLC and reverse ultrafiltration-HPLC

Tyrosinase inhibitors play an important role in cosmetic products, food supplements and medicinal industries. In this study, a new facile method based on tyrosinase immobilized magnetic fishing (IMF) coupled with high performance liquid chromatography-diode array detector-tandem mass spectrometry (HPLC-DAD-MS/MS) was developed to screen and identify tyrosinase binders from Glycyrrhiza uralensis root. Experiments were carried out to select optimal immobilization and incubation conditions. The activity of immobilized tyrosinase retained 76.3% after ten consecutive cycles, and remained over 95% when stored at 4°C for about two months. Eleven tyrosinase binders, including original compounds and transformation products were successfully screened and characterized from G. uralensis root, while dihydrodaidzein and pratensein were reported for the first time. Compared with ultrafiltration-HPLC assay, IMF-HPLC displayed many attractive advantages, including convenient solid-liquid separation ability, good stability, high reusability and activity, which indicated that IMF-HPLC had a broad applicability. The results indicated that IMF-HPLC method is a facile, effective and reproductive way to screen and identify active components from complex mixtures.

Glycyrrhiza uralensis Transcriptome Landscape and Study of Phytochemicals

Medicinal and industrial properties of phytochemicals (e.g. glycyrrhizin) from the root of Glycyrrhiza uralensis (licorice plant) made it an attractive, multimillion-dollar trade item. Bioengineering is one of the solutions to overcome such high market demand and to protect plants from extinction. Unfortunately, limited genomic information on medicinal plants restricts their research and thus biosynthetic mechanisms of many important phytochemicals are still poorly understood. In this work we utilized the de novo (no reference genome sequence available) assembly of Illumina RNA-Seq data to study the transcriptome of the licorice plant. Our analysis is based on sequencing results of libraries constructed from samples belonging to different tissues (root and leaf) and collected in different seasons and from two distinct strains (low and high glycyrrhizin producers). We provide functional annotations and the expression profile of 43,882 assembled unigenes, which are suitable for various further studies. Here, we searched for G. uralensis-specific enzymes involved in isoflavonoid biosynthesis as well as elucidated putative cytochrome P450 enzymes and putative vacuolar saponin transporters involved in glycyrrhizin production in the licorice root. To disseminate the data and the analysis results, we constructed a publicly available G. uralensis database. This work will contribute to a better understanding of the biosynthetic pathways of secondary metabolites in licorice plants, and possibly in other medicinal plants, and will provide an important resource to further advance transcriptomic studies in legumes.

Isolation of Liquiritigenin-4'-Apiosyl-Glucoside and Liquiritin from the Root of Glycyrrhiza uralensis by High-Performance Centrifugal Partition Chromatography

High-performance centrifugal partition chromatography (HPCPC) combined with ultraviolet detection was employed for the separation and purification of flavonoids from Glycyrrhiza. At the detection wavelength of 276 nm, two flavonoids, liquiritigenin-4'-apiosyl-glucoside and liquiritin, were successfully separated by HPCPC with an optimized two-phase solvent system composed of ethyl acetate-ethanol-water (1:0.1:1, v/v/v). The purity of these compounds was 95.0 and 97.1%, respectively, as determined by high-performance liquid chromatography. Their structures were identified by electrospray ion source mass spectroscopy (ESI-MS(n)) in the negative ion mode.

Protection of glycyrrhizic acid against AGEs-induced endothelial dysfunction through inhibiting RAGE/NF-κB pathway activation in human umbilical vein endothelial cells

Ethnopharmacological relevanceLicorice (Glycyrrhiza uralensis roots) is used as a traditional medicine for the treatment of diabetes mellitus and its vascular complications. Glycyrrhizic acid (GA, also known as Glycyrrhizin), a triterpenoid saponin glycoside, is considered to be a bioactive component in Licorice and is beneficial to diabetic vascular complications. Aim of studyThe present study was conducted to evaluate the potential protective activities on AGEs-induced endothelial dysfunction, including anti-apoptosis, antioxidant stress and anti-proinflammatory responses, and explore the underlying mechanism. Materials and methodsHuman umbilical vein endothelial cells (HUVECs) were incubated and pre-treated with GA (10−9–10−6M) or RAGE-Ab (5μg/ml) in the presence or absence of 200μg/ml AGEs. AO/EB fluorescence staining assay was performed to evaluate anti-apoptosis activity. The superoxide dismutase (SOD) activity and malondialdehyde (MDA) level in cell supernatant were detected by kits while the intracellular reactive oxygen species (ROS) generation was determined by 2,7-dichlorodihydrofluorescin diacetate (DCFH-DA) kit. Immunocytochemistry analysis was designed to determine transforming growth factor beta1(TGF-β1) protein expression while immunofluorescence analysis for RAGE and NF-kB. The protein expressions of TGF-β1, RAGE and NF-kB were analyzed by Western blot analysis. ResultsPretreatment with GA at a concentration of 10−8–10−6M significantly reduced the AGEs-induced apoptosis in HUVECs. GA significantly increased antioxidant enzyme SOD activity and decreased peroxide degradation product MDA level in a dose-dependent manner. Furthermore, GA also remarkably inhibited the overgeneration of AGEs-induced ROS. Both immunocytochemistry analysis and western blot analysis showed that GA significantly decreased the protein expression of poinflammatory cytokine TGF-β1 in a similar manner which RAGE-Ab did. Additionally, AGEs-induced RAGE and NF-kB protein expressions were down-regulated significantly by the pretreatment with GA or RAGE-Ab. ConclusionThese findings provide evidences that GA possesses protective activity on AGEs-induced endothelial dysfunction, including anti-apoptosis, anti-inflammation and antioxidant stress, via inhibiting RAGE/NF-kB pathway. GA might be an alternative for the prevention and treatment of diabetic vascular complications in an appropriate dosage.

Screening and establishment of the high-glycyrrhizin strain of licorice, Glycyrrhiza uralensis

Licorice, the root and stolon of Glycyrrhiza uralensis, is among the most important crude drugs in traditional oriental medicine. Glycyrrhizin, a triterpenoid saponin, is a major bioactive compound having several pharmacological activities. Here, we describe the screening of high-glycyrrhizin type strain from a same age population of G. uralensis cultivated under the same conditions in a field. Glycyrrhizin content of the selected strain was reached over 4% (average 2.11%, n=100). We established clonal plants of the selected high-glycyrrhizin strain using in virto micro-propagation by plant tissue culture.

Inhibitory effects of glycyrrhizae radix and its active component, isoliquiritigenin, on Aβ(25–35)-induced neurotoxicity in cultured rat cortical neurons

This study investigated an ethanol extract from Glycyrrhizae radix (GR), the root of Glycyrrhiza uralensis (Leguminosae), for possible neuroprotective effects on neurotoxicity induced by amyloid β protein (Aβ) (25-35) in cultured rat cortical neurons. Exposure of cultured cortical neurons to 10 μM Aβ (25-35) for 36 h induced neuronal apoptotic death. GR (10-50 μg/mL) prevented the Aβ (25-35)-induced neuronal apoptotic death, as assessed by a MTT assay and Hoechst 33342 staining. Furthermore, GR decreased the expression of Bax and active caspase-3, proapoptotic proteins, and increased Bcl-2, an antiapoptotic protein. GR also significantly inhibited Aβ (25-35)-induced elevation of the intracellular Ca(2+) concentration ([Ca(2+)](i)) and generation of reactive oxygen species (ROS) measured by fluorescent dyes. Isoliquiritigenin (1-20 μM), isolated from GR as an active component, inhibited Aβ (25-35)-induced neuronal apoptotic death, elevation of [Ca(2+)](i), ROS generation, and the change of apoptosis-associated proteins in cultured cortical neurons, suggesting that the neuroprotective effect of GR may be, at least partly, attributable to this compound. These results suggest that GR and isoliquiritigenin prevent Aβ (25-35)-induced neuronal apoptotic death by interfering with the increases of [Ca(2+)](i) and ROS, and GR may have a possible therapeutic role for preventing the progression of neurodegenerative disease such as Alzheimer's disease.

Effect of water deficit on biomass production and accumulation of secondary metabolites in roots of Glycyrrhiza uralensis.

Two-year-old seedlings of licorice plant (Glycyrrhiza uralensis Fisch) were exposed to three degrees of water deficit, namely weak (60–70%), moderate (40–50%), and strong (20–30%) relative water content in soil, whereas control plants were grown in soil with 80–90% water content. Moderate and strong water deficit decreased the net photosynthetic rate, stomatal conductance, and biomass production. Water use efficiency and the root-to-shoot ratio increased significantly in response to water deficit, indicating a high tolerance to drought. Weak water deficit did not decrease root biomass production, but significantly increased the production of glycyrrhizic acid (by 89%) and liquiritin (by 125%) in the roots. Therefore, a weak water deficit can increase the yield of root medical compounds without negative effect on root growth.