[Cloning and bioinformatics analysis of ß-amyrin synthase in Dipsacus asper].

Dipsaci Radix is one of the commonly used Chinese medicinal materials in China, with a long history. It has the medicinal activities of nourishing liver and kidney, recovering from broken sinews, and treating bone fracture. Triterpenoid saponins are the main functional ingredients of Dipsacus asper. ß-Amyrin synthases(ß-AS) as a superfamily of oxidosqualene cyclases(OSCs) can catalyze the construction of the skeleton structure of oleanane-type triterpenoid saponins. There are only a few studies about the ß-AS in D. asper, and the catalytic mechanism of this enzyme remains to be explored. To enrich the information of ß-AS, according to the transcriptome sequencing results, we cloned DaWß-AS gene from D. asper into a specific vector for heterologous expression in Escherichia coli. In the meantime, real-time PCR was performed to analyze the relative expression of DaWß-AS in four different tissues of D. asper. The results of RT-qPCR showed DaWß-AS had the highest expression level in leaves. Bioinformatics results indicated that DaWß-AS had a conserved domain of PLN03012 superfamily, belonging to the cl31551 superfamily. There was no transmembrane domain or signal peptide in DaWß-AS. This study provides a scientific basis for revealing the biological pathways of triterpenoid saponins in D. asper, which will facilitate the biosynthesis of the associated saponins and afford reference for the cultivation and development of high-quality resources of D. asper.

The antiviral mechanism of the crude extract from the flowers of Trollius chinensis based on TLR 3 signaling pathway.

The effects of crude extract from the flowers of Trollius chinensis on expressions of mRNA and proteins related to vital genes (TLR 3, TBK 1, IRF 3 and IFN ß) in TLR 3 signaling pathway were investigated in the presence/absence of Polyinosinic acid-polycytidylic acid (PolyI: C) to ascertain the antiviral mechanism of these flowers. Real-time PCR and western blot were applied to determine the expressions of mRNA and proteins, respectively, and immunofluorescence assay was employed to study the effect on IRF 3 distribution between nuclei and cytoplasma. In the absence of PolyI:C, the crude extract reduced the mRNA expression of TLR 3, IRF 3 and IFN ß and the protein expression of TLR 3, and increased the protein expression of IRF 3 and the distribution of IRF 3 in nuclei. In the presence of PolyI:C, the extract reduced the mRNA and protein expressions of TLR 3 and the mRNA expression of IFN ß, meanwhile inhibited the translocation of IRF 3 into nuclei. The antiviral mechanism of the crude extract from the flowers of T. chinensis is to protect the host from inflammatory damage through intervening the TLR 3 signaling pathway and reducing the secretion of inflammatory factors.

Anti-inflammatory effect of the compounds from the flowers of Trollius chinensis.

In order to investigate the anti-inflammatory activity of flavonoids, phenolic acids, and alkaloids from the flowers of Trollius chinensis, some representative compounds, namely, orientin, 2"-O-ß-L-galactopyranosylorientin, vitexin, quercetin, isoquercetin, luteolin, veratric acid, proglobeflowery acid, trollioside, and trolline were selected to study their inhibitory effects against LPS-induced NO, IL-6, and TNF-ß release in RAW264.7 cells. At the higher concentration, both phenolic acids and flavonoids inhibited the production of NO, whereas only phenolic acids showed this effect at the lower concentration. Although trolline had stronger cytotoxicity, it exhibited a potential effect of decreasing NO production induced by LPS in the non-toxic concentration range. In addition, all tested compounds decreased the production of IL-6 and TNF-a by almost 50% at both the higher and lower concentrations. It is concluded that the anti-inflammatory activity of the phenolic acids is stronger than that of the flavonoids.

Analysis of Non-Volatile Chemical Constituents of Menthae Haplocalycis Herba by Ultra-High Performance Liquid Chromatography-High Resolution Mass Spectrometry.

Menthae Haplocalycis herba, one kind of Chinese edible herbs, has been widely utilized for the clinical use in China for thousands of years. Over the last decades, studies on chemical constituents of Menthae Haplocalycis herba have been widely performed. However, less attention has been paid to non-volatile components which are also responsible for its medical efficacy than the volatile constituents. Therefore, a rapid and sensitive method was developed for the comprehensive identification of the non-volatile constituents in Menthae Haplocalycis herba using ultra-high performance liquid chromatography coupled with linear ion trap-Orbitrap mass spectrometry (UHPLC-LTQ-Orbitrap). Separation was performed with Acquity UPLC® BEH C18 column (2.1 mm × 100 mm, 1.7 µm) with 0.2% formic acid aqueous solution and acetonitrile as the mobile phase under gradient conditions. Based on the accurate mass measurement (<5 ppm), MS/MS fragmentation patterns and different chromatographic behaviors, a total of 64 compounds were unambiguously or tentatively characterized, including 30 flavonoids, 20 phenolic acids, 12 terpenoids and two phenylpropanoids. Finally, target isolation of three compounds named Acacetin, Rosmarinic acid and Clemastanin A (first isolated from Menthae Haplocalycis herba) were performed based on the obtained results, which further confirmed the deduction of fragmentation patterns and identified the compounds profile in Menthae Haplocalycis herba. Our research firstly systematically elucidated the non-volatile components of Menthae Haplocalycis herba, which laid the foundation for further pharmacological and metabolic studies. Meanwhile, our established method was useful and efficient to screen and identify targeted constituents from traditional Chinese medicine extracts.

Enzymatic transformation of vina-ginsenoside R7 to rare notoginsenoside ST-4 using a new recombinant glycoside hydrolase from Herpetosiphon aurantiacus.

An eco-friendly and convenient preparation method for notoginsenoside ST-4 has been established by completely transforming vina-ginsenoside R7 using a recombinant glycosidase hydrolyzing enzyme (HaGH03) from Herpetosiphon aurantiacus. This enzyme specifically hydrolyzed the glucose at the C-20 position but not the external xylose or two inner glucoses at position C-3. Protein sequence BLAST revealed that HaGH03, composed of 749 amino acids and presumptively listed as a member of the family 3 glycoside hydrolases, has highest identity (48 %) identity with a thermostable ß-glucosidase B, which was not known of any functions for ginsenoside transformation. The steady state kinetic parameters for purified HaGH03 measured against p-nitrophenyl ß-D-glucopyranoside and vina-ginsenoside R7 were K M = 5.67 ± 0.24 µM and 0.59 ± 0.23 mM, and k cat = 69.2 ± 0.31/s and 2.15 ± 0.46/min, respectively. HaGH03 converted 2.5 mg/mL of vina-ginsenoside R7 to ST-4 with a molar yield of 100 % and a space-time yield of 104 mg/L/h in optimized conditions. These results underscore that HaGH03 has much potential for the effective preparation of target ginsenosides possessing valuable pharmacological activities. This is the first report identifying an enzyme that has the ability to transform vina-ginsenoside R7 and provides an approach to preparing rare notoginsenoside ST-4.

A universal quantitative ¹H nuclear magnetic resonance (qNMR) method for assessing the purity of dammarane-type ginsenosides.

INTRODUCTION: Quantitative (1)H-NMR (qNMR) is a well-established method for quantitative analysis and purity tests. Applications have been reported in many areas, such as natural products, foods and beverages, metabolites, pharmaceuticals and agriculture. The characteristics of quantitative estimation without relying on special target reference substances make qNMR especially suitable for purity tests of chemical compounds and natural products. Ginsenosides are a special group of natural products drawing broad attention, and are considered to be the main bioactive principles behind the claims of ginsengs efficacy. The purity of ginsenosides is usually determined by conventional chromatographic methods, although these may not be ideal due to the response of detectors to discriminate between analytes and impurities and the long run times involved. OBJECTIVE: To establish a qNMR method for purity tests of six dammarane-type ginsenoside standards. METHODS: Several experimental parameters were optimised for the quantification, including relaxation delay (D1), the transmitter frequency offset (O1P) and power level for pre-saturation (PL9). The method was validated and the purity of the six ginsenoside standards was tested. Also, the results of the qNMR method were further validated by comparison with those of high performance liquid chromatography. CONCLUSION: The qNMR method was rapid, specific and accurate, thus providing a practical and reliable protocol for the purity analysis of ginsenoside standards.

Hepatic metabolism: a key component of herbal drugs research.

Liver is the largest metabolic organ for a wide range of endogenous and exogenous compounds and plays a crucial part in the pharmacokinetics and pharmacodynamics through various metabolic reactions. This review provides a progressive description of hepatic metabolism of herbal drugs with respect to metabolic types and investigational methods. In addition, the problems encountered during the research process are discussed.

[Structure and biological action on cardiovascular systems of saponins from Panax notoginseng].

Notoginseng Radix et Rhizoma (Sanqi), the underground part of Panax notoginseng (Burk.) F. H. Chen (Araliaceae) is commonly used in Chinese medicine for treatment of haemorrhage, haemostasis, swelling, etc. The aerial part including leaves, flowers and fruits are also applied for similar functions. Triterpenoid saponins are considered to be responsible for the biological activities of Sanqi. Up to date, more than 100 saponins have been isolated from theroots, rhizomes, leaves, flowers and fruits of P. notoginseng. The reported saponins can be classified into protopanaxadiol (PPD), protopanaxatriol (PPT), C17 side-chain varied and other types, according to the skeletons of the aglycons. The present review summarizes the saponins isolated from P. notoginseng and their distribution in different medicinal organs, as well as the pharmacological actions on cardiovascular system.

[Study on Stability of Human Intestinal Bacterial Biotransformation Model].

UNLABELLED: Objective: To investigate the stability of human intestinal bacterial biotransformation model using isoquercetin as the substrate of transformation. METHODs: The in vitro transformation model was established using the intestinal bacteria form different volunteers, or different passages of the same volunteer in accordance with the "biotransformation model of human intestinal bacteria and its standard operating procedures" to transform isoquercetin. RESULTS: Within 24 hours, all models established with the intestinal bacteria from different volunteers could transform isoquercetin to quercetin and the transformation efficiency was inclined to increase with the increase of the number of culture passages. CONCLUSION: The intestinal bacterial model established in accordance with the "standard operating procedures" is stable and the results obtained with this model are reproducible, which demonstrats the suitability of this model for the investigation of the chemical constituents of Chinese medicinal materials.

Distribution patterns of the contents of five active components in taproot and stolon of Glycyrrhiza uralensis.

Wild or cultivated Glycyrrhiza uralensis FISCHER (G. uralensis) are the main source of licorice, and they contain the similar compounds, such as the triterpenoid saponins and flavonoids, but above two kinds of the components contents are low level in the cultivated licorice. To produce the high quality cultivated licorices, researchers studied the affecting factors about the compounds producing in the plant of licorice, and then found that the growth years, genetic differences and water deficit are all the important factors. In this paper, we found that there were different distribution patterns of the main five active components (FAC) including glycyrrhizin, liquiritin, isoliquiritin, liquiritigenin and isoliquiritigenin in the taproot and stolon of G. uralensis and maybe they are also important influence factors to the FAC contents of the licorices. In wild G. uralensis, the contents of FAC tended to be lower in the younger parts of the stolon, and in the cultivated G. uralensis taproot, the contents of glycyrrhizin, liquiritin and isoliquiritin tended to increase from top to end, contrary to the contents of liquiritigenin and isoliquiritigenin, which increased first and then decreased. Our results will contribute to the analyses of factors which influence the quality of licorice, and provide some reference for cultivating high quality licorices for herbal medicine.

Absorbability, mechanism and structure-property relationship of three phenolic acids from the flowers of Trollius chinensis.

The absorption properties, mechanism of action, and structure-property relationship of three phenolic acids isolated from the flowers of Trollius chinensis Bunge, namely, proglobeflowery acid (PA), globeflowery acid (GA) and trolloside (TS), were investigated using the human Caco-2 cell monolayer model. The results showed that these three phenolic acids were transported across the Caco-2 cell monolayer in a time and concentration dependent manner at the Papp level of 10-5 cm/s, and their extent of absorption correlated with their polarity and molecular weight. In conclusion, all three of these compounds were easily absorbed through passive diffusion, which implied their high bioavailability and significant contribution to the effectiveness of T. chinensis.

Intestinal bacterial transformation - a nonnegligible part of Chinese medicine research.

Intestinal bacteria play an essential part in the metabolism of the constituents of herbal drugs, and a lot of investigations have been done to unveil their functions and mechanisms in modification of these constituents and their effect. This review provides a progressive description of intestinal bacterial transformation with respect to properties, reactions, correlation with the effect of herbal drugs, research interests, and methodology. In addition, the problems encountered during the investigation are addressed and perspectives are proposed.

Two cerebrosides isolated from the seeds of Sterculia lychnophora and their neuroprotective effect.

Two cerebrosides named 1-O-b-D-glucopyranosyl-(2S,3R,4E,8Z)-2-[(2-hydroxyoctadecanoyl)amido]-4,8-octadecadiene-1,3-diol (1) and soya-cerebroside I (2) were isolated from the seeds of Sterculia lychnophora for the first time. Their structures were completely characterized by spectroscopic methods including IR, MS and NMR. Compound 1 exhibited moderate neuroprotective effect against SH-SY5Y cell damage induced by hydrogen peroxide.

Dulbecco's modified eagle's medium and minimum essential medium--which one is more preferred for establishment of Caco-2 cell monolayer model used in evaluation of drug absorption?

The Caco-2 cell monolayer model is widely used in drug absorption studies. Dulbecco's Modified Eagle's Medium (DMEM) and Minimum Essential Medium (MEM) have been used alternatively in the development of this model, although they are different in composition which may affect the differentiation and junction formation of the Caco-2 cell monolayer. Two Caco-2 cell monolayers cultured in both media were compared herein in order to underlay the standardization of this model. These two monolayers were comparatively evaluated regarding reliability and stability by morphology, transepithelial electrical resistance (TEER), alkaline phosphatase (AKPase) activity and transport experiments. Although the results showed that characteristic microvilli were present at the apical side of both monolayers, the dynamic change of TEER of the monolayer cultured in DMEM was more stable than that cultured in MEM, and AKPase activity of the former was stronger than that of the latter. Furthermore, the quantity of atenolol, a key indicator usually used for assessment of this model, across the monolayer cultured in MEM was significantly more than that cultured in DMEM. Therefore, the Caco-2 monolayer cultured in DMEM was more reliable and stable than that cultured in MEM, and thus the former was preferred for drug absorption investigation in vitro.

[Research progress of alternative production approaches of salidroside].

Salidroside, one of the active components of Rhodiola plants, is a phenolic glycoside with significant biological activities. The investigation and development of alternative production approaches of salidroside is of high academic and application values due to the limited resource of Rhodiola plants, and from which the low yield of salidroside. This review summarized the research progress and perspective of the alternative production approaches of salidroside including both chemosynthetic and biosynthetic methods and pathways.

[Evaluation of quality coherence of prepared slices of polygoni cuspidati rhizoma commercially available in China based on HPLC fingerprint].

OBJECTIVE: To evaluate the quality coherence of the prepared slices of Polygoni Cuspidati Rhizoma commercially available in China and provide a reference for their quality evaluation. METHODS: The fingerprints were obtained using HPLC method, and analyzed with Chromatographic Fingerprint Similarity Evaluation System (2004A Version) provided by Chinese Pharmacopoeia Commission. The experiment was carried out with an Agilent TC-C18 column (250 mm x 4.6 mm, 5 microm) using acetonitrile-0.05% aqueous solution of phosphoric acid as mobile phase at the flow rate of 1.0 mL/min, detection wavelength of 230 nm, and temperature of 25 degrees C. RESULTS: The fingerprint for Polygoni Cuspidati Rhizoma was established. 21 common characteristic peaks were identified and the similarities of 24 batches of prepared slices of Polygoni Cuspidati Rhizoma were between 0.882 - 0.988. CONCLUSION: The quality of the prepared slices of Polygoni Cuspidati Rhizoma commercially available in China is comparable.

[Study on the chemical components of volatile oil from Euphorbia pekinensis radix].

OBJECTIVE: To analyze the volatile oil from Radix Euphorbia Pekinensis. METHODS: Volatile oil was extracted from Radix Euphorbia Pekinensis by steam distillation and GC-MS was employed for detecting the content of the constituents. The relative content of the chemical constituents were calculated using area normalization method. RESULTS: 35 peaks were separated and 29 constituents were identified. The yield rate of volatile oil extracted from the dried radix of Euphorbia Pekinensis was 0.3%. CONCLUSION: The main components of volatile oil were agarospirol and hedycargol and their contents were 49.23% and 20.66% respectively. This paper provides valuable experimental data for further research of Radix Euphorbia Pekinensis.

A mathematical model for quality evaluation of total saponins of Panax japonicas based on hypolipidemic activity.

Objective: The chemical finger printing-based methods for evaluating TCMs quality can report partial of TCMs quality without linking to effective constituents. In this study, a mathematical model was established for the quality evaluation of total saponins of Panax japonicus (TSPJ), a folk medicine in China and Japan for treating diseases, through coupling the dynamic changes of chemical constitutions with corresponding activities. Methods: High-performance liquid chromatography (HPLC) fingerprints were applied to establish the chromatographic database of TSPJ. The associated hypolipidemic activity database was determined by TG assay using HepG2 cell model. Correlation analyses of two databases were performed by partial least squares (PLS) for calculating regression coefficients, and the interval value of YZL value (the ratio of positive and negative peak-to-peak area coefficient) closely related to hypolipidemic activity was refined by the formula of Norminv function to value the quality of TSPJ. Results: In this study, the chromatographic data of 16 common peaks were obtained from 20 batches of TSPJ. After the estimate by this mathematical evaluation model, seven peaks were positively correlated with hypolipidemic activity, and nine peaks were negatively correlated with hypolipidemic activity. When the YZL value was less than 0.7861, the quality of sample was inferior, while YZL value was more than 6.6992, and the quality of samples was superior. The quality of another ten batches of TSPJ was further assessed to verify this method. Conclusion: These results indicated that the established model could be usefully applied to evaluate the quality of TSPJ in the hypolipidemic activity.

Functional characterization of two chalcone isomerase (CHI) revealing their responsibility for anthocyanins accumulation in mulberry.

Mulberry (Morus sp., Moraceae) is an important economic crop plant and mulberry fruits are rich in anthocyanidins. Chalcone isomerase (CHI) catalyzes the conversion of chalcones to flavanones providing precursors for biosynthesis of anthocyanidins. In this study, bona fide CHIs were cloned and characterized from different Morus species with differently colored fruits (Morus multicaulis, Mm and Morus alba variety LvShenZi, LSZ). Enzymatic assay of MmCHI1 and MmCHI2 showed that they can utilize naringenin chalcone as substrate. The catalytic efficiency of MmCHI2 and LSZCHI2 are approximately 200 and 120-fold greater than that of MmCHI1 respectively. Phylogenetic analysis showed the two mulberry CHIs belonged to different sub-clade of Type I CHI1 named type IA (CHI2) and type IB (CHI1). Type IB CHIs are mulberry specific. MmCHI1 and MmCHI2 had similar expression profiles and showed preferred expression in fruits. In addition, both mulberry CHI1 and CHI2 played roles in the response to excess zinc stress and sclerotiniose pathogen infection. Both MmCHI1 and MmCHI2 expression levels showed positive close relationship with anthocyanins content during fruit ripening process. The co-expression of MmCHI1 and MmCHI2 was observed during fruit ripening process and in transgenic mulberry. VIGS (virus induced gene silence) targeting on MmCHI1 and MmCHI2 showed significant down-regulation of MmCHI2 instead of MmCHI1 would result in significant (about 50%) decrease in anthocyanins content. MmCHI2 is the dominant CHI for anthocyanins accumulation in mulberry. The results presented in this work provided insight on bona fide CHIs in mulberry and reveal their roles in anthocyanins accumulation.

A new natural ceramide from Trollius chinensis Bunge.

A new natural product named trolliamide was isolated from Trollius chinensis Bunge. Its structure was determined as 2-hydroxy-tetracosanoic acid(2,3-dihydroxy-1-hydroxymethyl-heptadec-7-enyl)-amide by spectroscopic methods, including UV, IR, MS and NMR. This is the first report of a ceramide isolated from Trollius chinensis.