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A total of 33 structurally diverse isoquinoline alkaloids were isolated from the rhizomes of Menispermum dauricum, including seventeen benzylisoquinoline analogues (menisperdaurines A-Q, 1-17), five protoberberine analogues (menisperdaurines R-V, 18-22), a quaternary phenanthrene alkaloid (menisperdaurine W, 23) and ten known compounds (24-33). Compound structures, including absolute configurations, were determined by extensive spectroscopic methods, quantum chemical calculations of chemical shifts, and calculated and experimental electronic circular dichroism (ECD) data. Compounds 1-5 were glycosidic benzylisoquinolines with glucose moieties attached at the C-12 position. Compound 8 was the first example that was isolated from the rhizomes of Menispermum dauricum, benzylisoquinoline and an aromatic unit connected by a sugar bridge. Compounds were evaluated for their inhibitory effects on the dopamine D1 receptor. Compounds 1, 8, 21, 24 and 29 showed potent D1 antagonistic activities, with IC

With EP(epoxy resin) as matrix resin, DCA(dicyandiamide) as curing agent and modified imidazole as curing accelerator, and adding fillers and other additives, a single-component flow-type EP underfill adhesive was prepared. The curing temperature was determined by testing gelation time and characterizing FT-IR(infrared spectroscopy). And the influences of fillers types and proportions on the viscosity, thermal conductivity, dielectric constant and bonding strength of adhesives were discussed. The research results indicated that the adhesive had good combination property and could fully meet the application requirements. when mass ratios of m(EP):m(DCA):m(modified imidazole) was 100:8:5, w(filler)was 60% in EP and m(Al2O3):m(SiO2) was 1:5, and mass fractions of silane coupling agent and dispersing agent were all 0.5% in EP, and curing process was "85°C/30min→120°C/1h"(cured for 30 minutes at 85°C, and cured for 1h at 120°C), Its shear strength was 15.33 MPa, thermal conductivity was 0.793 W/(m.K), and viscosity was 6.06 Pa.S.

Ketogulonicigenium vulgare Y25 is used in the production of vitamin C, which is responsible for the conversion reaction of l-sorbose to l-ketogulonic acid in mixed culture fermentation with Bacillus species 8. The entire genome of Ketogulonicigenium vulgare Y25 was sequenced to elucidate the metabolic pathway of sorbose and to obtained detailed insights into the growth potential of the organism. The complete genome sequence of Ketogulonicigenium vulgare Y25 was determined by the Beijing Genome Institute (Shenjun, China) using Solexa technology. A total of 221 million high-quality base pairs, giving 67.2-fold coverage of the genome, were assembled into 36 contigs using by SOAP software (http://soap.genomics.org.cn) 7. Then, the contigs were joined into 14 scaffolds using paired-end information. Gaps between contigs were closed by custom primer walks or by PCR amplification followed by DNA sequencing. The genome of Ketogulonicigenium vulgare Y25 consists of a circular chromosome and two plasmids. The chromosome is composed of 2,776,084 bp, with a G+C content of 61.72%. One plasmid contains 268,675 bp, with a G+C content of 61.35%, and the other contains 243,645 bp, with a G+C content of 62.63%. Hence, the total size of the genome is 3,288,404 bp and the average G+C content is 61.76%. There are a total of 3,290 putative open reading frames (2,807 [chromosome], 256 [pYP1], and 227 [pYP2]) using Glimmer, giving a coding intensity of 91.05%. A total of 59 tRNA genes for all 20 amino acids but tyrosine and five 16S-23S-5S rRNA operons were identified. Four genes encoding sorbose dehydrogenase were found in the chromosome. All of them were cloned and characterized. The result indicated that every one could transform l-sorbose into 2-keto-gulonic acid and required pyrroloquinoline quinine for the prosthetic groups in vitro (unpublished data). Sequence alignment analysis showed that they hadhigh homology in nucleic acid and amino acid sequences 1, 4, 9, and 10. It is estimated that multiple copies of the sorbose dehydrogenase gene can be attributed to highly efficient conversion of sorbose to 2-keto-gulonic acid. A pqqABCDE cluster of coenzyme PQQ biosynthesis has also been isolated. It shows the same arrangement of pqq genes as that in other species: a small pqqA gene with its own promoter followed by an operon with the other four genes2, 3, 5, 6. In addition, several genes encoding sorbitol dehydrogenase, sorbose reductase, sorbsone dehydrogenase, etc., were annotated in the genome. The Y25 genome sequence and its curated annotation are important assets to better understand the physiology and metabolic potential of Ketogulonicigenium vulgare and will open up new opportunities in the functional genomics of this species.