The Chemical Constituents from the Bulbs of Ornithogalum caudatum

A new natural product (1) together with 26 know compounds were isolated from the Bulbs of Ornithogalum caudatum. Their structures were established on the basis of spectral analyses as n-butyl pyroglutamate (1), nonadecyl alcohol(2), eicosanol(3), behenic acid(4), b-sitosterol(5), stigmasterol(6), glycerol 1-monocerotate(7), pyrocatechol(8), p-ethoxybenzoic acid(9), p-coumarinic acid(10), protocatechuric acid(11), ursolic acid(12), betulinic acid(13), fumaric acid(14), succinic acid(15), uracil(16), xanthine(17), quercetin(18), kaempferol (19), isorham-netin(20), adenosine(21), daucosterol(22), stigmasterol 3-O-b-D-glucopyranoside(23), quercetin 3-O-b-D-glucopyra-noside(24), kaempferol 3-O-b-D-glucopyranoside(25), rutin(26), and kaempferol 3-O-b-rutinoside(27). All of them, except compound 5, were isolated from this plant for the first time.

工程总承包：一条荆棘路

工程总承包以其独特的优势受到越来越多人的青睐。然而,这却是一条光荣的荆棘路：除了施工企业尚需苦练内功,更关键的则是如何让业主改变其保守的理念和态度2006年10月30日至31日,由建设部和商务部联合主办的”推动工程总承包和对外承包高峰论坛”在北京举行,这是我国推行工程总承包和对外承包20多年来,第一次以政府的名义举办该主题下的大型论坛。

Inhibitory Effect of the Essential Oil from Hyptis suaveolens （L.） Poit on the Growth and Aflatoxins Synthesis of Aspergillus flavus

H. suaveolens （L.） Poit has been used in folk medicine revealing a wide pharmacological potential. This study aimed to evaluate the efficacy of the essential oil from 11. suaveolens leaves in inhibiting the growth of A. flavus LM257 and synthesis of aflatoxins Bl and B2. The essential oil at 20, 40 and 80 laL/mL strongly reduced the biomass and spore germination ofA. flavus. A 100% inhibition was found at 40 μL/mL and 80μL/mL, while at 20 μL/mL the growth depressed over 50% for both tested parameters. The essential oil at all assayed concentrations totally inhibited the production of aflatoxin B1 and B2. From these results, the essential oil from 11. suaveolens leaves may be considered as an alternative and effective inhibitor ofA. flavus, in addition to offer some protective effect to the production of aflatoxins.

Spatial variation of stable isotopes in different waters during melt season in the Laohugou Glacial Catchment, Shule River basin

To evaluate isotopic tracers at natural abundances by providing basic isotope data of the hydrological investigations and assessing the impacts of different factors on the water cycle, a total of 197 water samples were collected from the Laohugou Glacial catchment in the Shule River basin northwestern China during the 2013 ablation seasons and analyzed their H- and O-isotope composition. The results showed that the isotopic composition of precipitation in the Qilianshan Station in the Laohugou Glacial catchment was remarkable variability. Correspondingly, a higher slope of δ180-δD diagram, with an average of 8.74, is obtained based on the precipitation samples collected on the Glacier No.la, mainly attributed to the lower temperature on the glacier surface. Because of percolation and elution, the bottom of the firn the isotopic composition at is nearly steady. The 6180 /altitude gradients for precipitation and melt water were -o.37%o/100 m and -o.34%o/100 m, respectively Exposed to the air and influenced by strong ablation and evaporation, the isotopic values and the 6180 vs 6D diagram of the glacial surface ice show no altitudinal effect, indicating that glacier ice has the similar origins with the firn. The variation of isotopic composition in the melt water, varying from -l0.7‰ to -16.9‰ （8180） and from -61.1%o to -122.1%o （6D） indicates the recharging of snowmelt and glacial ice melt water produced at different altitudes. With a mean value of -13.3‰ for 8180 and -89.7‰ for 8D, the isotopic composition of the stream water is much closer to the melt water, indicating that stream water is mainly recharged by the ablation water. Our results of the stable isotopic compositions in natural water in the Laohugou Glacial catchment indicate the fractionations and the smoothing fluctuations of the stable isotopes during evaporation, infiltration and mixture.

De novo characterization of the root transcriptome of a traditional Chinese medicinal plant Polygonum cuspidatum

Various active components have been extracted from the root of Polygonum cuspidatum. However, the genetic basis for their activity is virtually unknown. In this study, 25600002 short reads （2.3 Gb） of P. cuspidatum root transcriptome were obtained via lllumina HiSeq 2000 sequencing. A total of 86418 urtigenes were assembled de novo and annotated. Twelve, 18, 60 and 54 unigenes were respectively mapped to the mevalonic acid （MVA）, methyl-D-erythritol 4-phosphate （MEP）, shikimate and resveratrol biosynthesis pathways, suggesting that they are involved in the biosynthesis of pharmaceutically important anthra- quinone and resveratrol. Eighteen potential UDP-glycosyltransferase unigenes were identified as the candidates most likely to be involved in the biosynthesis of glycosides of secondary metabolites. Identification of relevant genes could be important in eventually increasing the yields of the medicinally useful constituents of the P. cuspidatum root. From the previously published transcriptome data of 19 non-model plant taxa, 1127 shared orthologs were identified and characterized. This information will be very useful for future functional, phylogenetic and evolutionary studies of these plants.