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Sinuscalide A (

Sol–gel zinc oxide (ZnO) thin films generally have non-uniform stripes. After annealing at high temperatures, these thin films are rough and granular. When ZnO rods are grown on such rough and non-uniform surface with the hydrothermal method, collimation, crystalline structure, and defect density are very poor. Here we explore a method to solve this problem. The ZnO thin film is first coated with an Au layer to prohibit the vertical extension of crystallization during the annealing period. As a result, the surface morphology of ZnO thin film is very flat and uniform after annealing. Afterwards, the ZnO rods are grown on the flat and uniform thin film, which gives rise to ZnO rods with very good collimation and crystalline structure. The extremely flat ZnO thin film even enables the fabrication of patterned ZnO rod arrays with regular shapes through lithography.

Solution-processed vanadium oxide (V2O5) as an anode interlayer is introduced between the organic layer and the Ag electrode for improving the performance of the low-cost inverted polymer solar cells hybridized with ZnO nanorods. Our investigations indicate that the solution-processed V2O5 interlayer as an electron-blocking layer can effectively prevent the leakage current at the organic/Ag interface. The power conversion efficiency is improved from 2.5% to 3.56% by the introduction of the V2O5 interlayer. The V2O5 interlayer also serves as an optical spacer to enhance light absorption, and thereby increases the photocurrent. Compared to the vacuum-deposited techniques, the fabrication of the solution-processed V2O5 interlayer is simple and effective. The solution-based approach makes it attractive for applications to mass production and potentially printed organic electronics.

Type 1a glycogen storage disease (GSD) is an autosomal recessive metabolic disorder caused by a deficiency in glucose-6-phosphatase (G6Pase). Polymerase chain reaction (PCR) and nucleotide sequence analysis were used to identify the location and nature of mutations at the G6Pase locus in two siblings affected with type 1a GSD. Both patients are compound heterozygotes with two different single nucleotide substitutions in the two G6Pase alleles. A guanine to adenine transition was identified at base position 327 in the exon 2, converting an arginine to a histidine at codon 83. The second substitution was a thymine to adenine transversion at base position 1101 in the exon 5, converting an isoleucine to an asparagine at codon 341. Family study reveals that both parents are heterozygous carriers : the father with a mutant G6Pase allele at exon 2, the mother with another mutant G6Pase allele at exon 5. This is the first family study in Taiwan on type 1a GSD identified by molecular analysis. The mutations identified herein are novel substitutions in the G6Pase gene. In addition, an adenine to guanine substitution was observed at base position 653 in the exon 5 of G6Pase gene in both sibling patients and their parents, as well as in 15 normal Chinese subjects and three normal Caucasian subjects.

Specimens of Suberites domuncula that had been cultured in aquaria for 4 weeks were analyzed for their associated fungi. A total of 81 fungal strains belonging to 20 different genera was isolated and identified by morphological and molecular methods. The most frequently isolated taxa were Cladosporium spp., Penicillium spp., Petriella sp., Phialophora spp. and Engyodontium album. Based on chromatographic and mass spectrometric analysis of fungal extracts, as well as on bioassay results, Aspergillus ustus, Penicillium sp., Petriella sp. and Scopulariopsis sp. were selected for in-depth analysis of their natural products. A total of 19 different fungal metabolites, including three new natural products, was isolated and structurally identified. A. ustus yielded two sesquiterpenes, a drimane derivative and deoxyuvidin, as well as a sesterterpene ophiobolin H. The drimane derivative had an ED50 value against L5178Y cells of 1.9 μg ml-1 in vitro. The crude extract of Petriella sp. was also strongly cytotoxic against the L5178Y cell line. The cyclic tetrapeptide WF-3161 was primarily responsible for the activity; the ED50 value was -1. It was identical to the known compound WF-3161 and had been previously isolated from Petriella guttulata. In addition to WF-3161, three further natural products were obtained and unequivocally identified as new derivatives of infectopyrone by one- and two-dimensional NMR spectroscopy and by mass spectroscopy. Of the new compounds, only dihydroinfectopyrone was active against L5178Y cells; the ED50 value was 0.2 μg ml-1. Penicillium sp. yielded the largest number of metabolites. Viridicatin, viridicatol, cyclopenin and cyclopenol suppressed larval growth of the polyphagous pest insect Spodoptera littoralis when incorporated into an artificial diet at an arbitrarily chosen concentration of 237 ppm. Viridicatol was the most active compound and had an ED50 value of ca. 50 ppm. Scopulariopsis sp. yielded three metabolites, including the known acetylcholinesterase inhibitors quinolactacin A1 and A2.

Stellaria nemorum L. and S. holostea L. (Caryophyllaceae) were investigated for their flavonoids. The new flavonoid 6-C-[(α-arabinopyranosyl)-( 1--2)-O-β- xylopyranosyl]apigenin (1) and the four known C-glycosides, 6-C-[(α-arabinopyranosyl)-(1--2)-O-β-glucopyranosyl]apigenin (2), apigenin 6-C-β- galactopyranoside-8-C-β-glucopyranoside (3), apigenin 6-C-β-glucopyranoside-8-C-α-arabinopyranoside (4), and apigenin 6-C-β-glucopyranoside-8-C-β- xylopyranoside (5) were isolated from the aerial parts of S. nemorum for the first time. Furthemore, five known flavonoids, 3,5,7-trihydroxy-3',5'- dimethoxyflavone (9), diosmetin 6-C-β-glucopyranoside (8), schaftoside (4), isoorientin (6) and orientin (7) were obtained from the aerial parts of S. holostea. Compounds 4, 8 and 9 are reported for the first time from this species. The structures of all isolated compounds were unambiguously elucidated by one- and two- dimensional NMR and mass spectral analysis, by acid hydrolysis, as well as by comparison with literature data. The crude extracts of the investigated species exhibited antimicrobial activity against Staphylococcus aureus, while none of the isolated compounds was found to be active.

Saponins are oligoglycosides with spirostane, steroid or triterpenoid aglycones as their genins, which constitute an important kind of natural product. Some of them exhibit prominent bioactivities, such as the saponins from Panax ginseng and Glycyrrhiza uralensis. Because of their high polarity and relatively complicated structures, it was time- and sample-consuming work to purify and identify them before the 1980’s. In the past decade, the continuing development of various advanced chromatographic materials and spectroscopic methods have made it possible to isolate and determine the structures of certain minor saponins ocurring only in small quantities in a short time.