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Ceo2 nanocrystals (cn) with different morphologies (i.e., cube, octahedron, and rod) are prepared and the facet-dependent effect of these ceo2 nanocrystals on the adsorption and dephosphorylation of phosphorylated molecules is investigated for the first time using the model p-nitrophenyl disodium orthophorphate (p-npp). due to their different surface atomic configurations, the {111} and {110} facets have much higher adsorption capacity and kinetic catalytic activities than {100} facets. all the ceo2 nanocrystals can intensely promote the dephosphorylation reaction owing to the strong interaction between ce cations and phosphoryl oxygens resulting in the cleavage of phosphoester bonds. as was expected, the above facet-dependent effect can be verified by the practical application results of the ceo2 nanocrystals on the capture and dephosphorylation of phosphopeptides. thus, surface engineering could be a useful and feasible strategy for not only fundamentally understanding the interaction between crystal facets and molecules but also effectively developing high-performance functional materials.

BACKGROUND Momordica charantia (MC) has been used for treating diabetes mellitus from ancient times in Asia, Africa and South America. There are many MC accessions in local markets. Polypeptide-P as a main hypoglycemic component in MC was first studied in this experiment to illustrate the different contents in MC of different accessions and different harvesting times. RESULTS Nineteen MC accessions collected from different regions were clustered into three groups using random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR) molecular markers. Content of polypeptide-P in the tested MC accessions was detected by western blot (WB) method. The WB results revealed that polypeptide-P was detected in MC accessions harvested in June and July but not in September and October. Furthermore, Polypeptide-P content corresponded well with the MC accessions. CONCLUSION Our results suggest that the MC accessions and the harvesting times or the weather during harvest play significant roles in high content of polypeptide-P. [[ArtCopyrightmsg]]

BACKGROUND:Momordica charantia (MC) is used in many Asian countries as a traditional functional food and medicine. Polypeptide-P, a 166 amino acid (AA) polypeptide isolated from MC seeds, has been reported to show hypoglycaemic effects in patients with type I or type II diabetes. The AA sequence of this peptide has been determined, but its gene sequence has yet to be published. RESULTS: In this study a gene-cloning strategy was employed to obtain the polypeptide-P gene sequence using degenerate reverse transcription polymer chain reaction and genome-walking methods. A complete 498 bp sequence encoding the polypeptide-P protein was cloned from MC seeds. Subsequent assays of the bioactivity of the expressed recombinant protein revealed that it had significant hypoglycaemic activity in alloxan-induced diabetic mice. This result suggests that recombinant polypeptide-P has hypoglycaemic effects. CONCLUSION: This is the first report of cloning and expression of the MC polypeptide-P gene. The cloned gene could be helpful for exploring the mechanisms of polypeptide-P gene expression and regulation in MC. Furthermore, this gene could be used as a potential tool both for screening MC varieties with high hypoglycaemically active substance content and for breeding new varieties of MC with high economic value, which could in turn be beneficial to farmers. Copyright © 2011 Society of Chemical Industry

A rapid, selective and sensitive hydrophilic interaction liquid chromatography (HILIC) coupled with tandem mass spectrometry (MS/MS) method was developed to determine 1-13C-l-methionine in rat serum. Proteins in serum were precipitated using acetonitrile and the supernatant was separated after centrifugation. 1-13C-l-phenylalnine was used as the internal standard. HILIC–tandem mass spectrometry analysis was performed on a hydrophilic interaction silica column (TSK-GEL AMIDE-80) using a linear gradient elution system, acetonitrile−5 mm ammonium acetate containing 0.1% formic acid and multiple reaction monitoring mode for 1-13C-l-methionine and 1-13C-l-phenylalnine. The assay was validated with a linear range between 10 and 150 ng mL−1 (r ≥ 0.99) and a lower limit of quantification of 10 ng mL−1, calculated with weighted (1/x2) least squares linear regression. The RSD of intra-day precision was smaller than 3.6% and the inter-day RSD less than 6.5%, while the average recovery was 100.48% with an RSD of accuracy within 2.9%, determined from quality control samples. The HILIC-MS/MS method was fully validated and successfully applied to the in vivo pharmacokinetic study of stable-isotope 1-13C-l-methionine in rats. Copyright © 2011 John Wiley & Sons, Ltd.

Danshen root (Salvia miltiorrhiza Radix et Rhizoma) is a representative Chinese herb containing multiple components contributing to its polyvalent bioactivities. Advanced analysis approaches are needed to obtain a comprehensive picture of the targeting constituents in complete matrix. In this study, a chromatographic fingerprinting method to monitor simultaneously the hydrophilic and lipophilic constituents was developed for the quality evaluation of Danshen root and its preparations. Ten hydrophilic and nine lipophilic components were identified using HPLC-diode array detection-electrospray-MS (HPLC-DAD-ESI/MS) by comparing with the available references and reported data. Using the established method, 13 Danshen root samples collected from different sources, and 21 batches of Danshen preparations including tablets, injections, capsules, and dropping pills produced by different manufacturers were analyzed and their chromatographic fingerprints (CFP) were constructed. The results showed that the products of Danshen roots such as the tablets and capsules contained both the hydrophilic and lipophilic components, while the injections and dropping pills contained mainly the hydrophilic components. Principal components analysis (PCA) was applied for the statistical analysis of the fingerprinting data of crude herb and its preparations. The established CFPs demonstrate the representative chemical profiling of the existing components and can be applied to the authentication and quality assessment of Danshen roots and other Danshen containing formulated preparations.

4-Coumarate: coenzyme A ligase (4CL) is one of the key enzymes in phenylpropanoid metabolism leading to series of phenolics, including water-soluble phenolic acids, which are important compounds determining the medicinal quality of Danshen (Salvia miltiorrhiza Bunge), a traditional Chinese medicinal herb. To investigate the function of 4CL in the biosynthesis of water-soluble phenolic acid in Danshen, we have cloned two cDNAs (Sm4CL1 and Sm4CL2) encoding divergent 4CL members by applying nested reverse transcription-polymerase chain reaction (RT-PCR) with degenerate primers followed by 5′/3′ rapid amplification of cDNA ends (RACE) (Note, these sequence data have been submitted to the GenBank database under accession numbers AY237163 and AY237164). Either of the coding regions was inserted into a pRSET vector and a kinetic assay was performed with purified recombinant proteins. The substrate utilization profile of Sm4CL1 was distinct from that of Sm4CL2. The Km values of Sm4CL1 and Sm4CL2 to 4-coumaric acid were (72.20±4.10) and (6.50±1.45) μmol/L, respectively. These results, in conjunction with Northern blotting and other information, imply that Sm4CL2 may play an important role in the biosynthesis of water-soluble phenolic compounds, whereas Sm4CL1 may play a minor role in the pathway. Southern blotting analysis suggested that both Sm4CL1 and Sm4CL2 genes are present as a single copy and are located at different sites in the genome. (Managing editor: Wei Wang)

Agrobacterium rhizogenes Conn. causes hairy root disease in plants. Hairy root-infected A. rhizogenes is characterized by a high growth rate and genetic stability. Hairy root cultures have been proven to be an efficient means of producing secondary metabolites that are normally biosynthesized in roots of differentiated plants. Furthermore, a transgenic root system offers tremendous potential for introducing additional genes along with the Ri plasmid, especially with modified genes, into medicinal plant cells with A. rhizogenes vector systems. The cultures have turned out to be a valuable tool with which to study the biochemical properties and the gene expression profile of metabolic pathways. Moreover, the cultures can be used to elucidate the intermediates and key enzymes involved in the biosynthesis of secondary metabolites. The present article discusses various applications of hairy root cultures in plant genetic engineering and potential problems associated with them. (Managing editor: Wei Wang)

Two novel compounds, (9R)-4-methoxy-9H-fluorene-2,5,9-triol (1a) and 2,7-dihydroxy-8-methoxyphenanthro[4,5-bcd]pyran-5(5H)-one (2) were isolated from the stems of the orchid Dendrobium chrysotoxum Lindl. Their structures were established spectroscopically, by chemical derivatization, and by single-crystal X-ray diffraction analysis. The absolute configuration of 1a was determined by Mosher's method. Neither compound showed antitumoral activity.