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Synthesis and properties of a luminescent organic material with triphenylamine and pentiptycene units

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Chinese Chemical Letters 2007年第7期18卷 820-822页

作者： qing guo he Xi Peng guo Jian Gong Cheng Feng Lian Bai Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 China Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

A donor-bridge-donor compound for blue light-emitting with triphenylamine as donor and pentiptycene derivative units as bridge was synthesized via Sonogashira reaction. The chemical structure was confirmed by NMR and MALDI-TOF MS. It emits blue light peaked at 442 nm with a FWHM of 59 nm in CH2Cl2. Fluorescent quantum efficiency in THF is 82% relative to 9,10-diphenylanthracene. A slight hypsochromic shift was found in its drop-cast film. Cyclic voltammetry revealed that it has high HOMO level corresponding to hole transporting character.

关键词： Triphenamine Pentiptycene Sonogashira reaction Blue light Hole transport

Optimization of acidic extraction of astaxanthin from Phaffia rhodozyma

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第1期9卷 51-59页

作者： Hui NI Qi-he CheN guo-qing he Guang-bin WU Yuan-fan YANG School of Biosystem Engineering and Food Science Zhejiang University Hangzhou 310029 China School of Bioengineering Jimei University Xiamen 361021 China

Optimization of a process for extracting astaxanthin from Phaffia rhodozyma by acidic method was investigated, regarding several extraction factors such as acids, organic solvents, temperature and time. Fractional factorial design, central composite design and response surface methodology were used to derive a statistically optimal model, which corresponded to the following optimal condition： concentration of lactic acid at 5.55 mol/L, ratio of ethanol to yeast dry weight at 20.25 ml/g, temperature for cell-disruption at 30 ℃, and extraction time for 3 min. Under this condition, astaxanthin and the total carotenoids could be extracted in amounts of 1294.7 μg/g and 1516.0 μg/g, respectively. This acidic method has advantages such as high extraction efficiency, low chemical toxicity and no special requirement of instruments. Therefore, it might be a more feasible and practical method for industrial practice.

关键词： Astaxanthin Phaffia rhodozyma Extracting Optimization Acidic method

A two-dimensional constant-weight sparse modulation code for volume holographic data storage

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第5期12卷 430-435页

作者： Hua-rong GU Liang-cai CAO qing-sheng he guo-fan JIN State Key Laboratory of Precision Measurement Technology and Instruments Tsinghua UniversiO Beijing 100084 China

In order to simplify the threshold determination,reduce the inter-pixel cross-talk,and improve the storage density for high-density volume holographic data storage,a two-dimensional constant-weight sparse modulation code is *** evaluation criteria and design rules are investigated based on the page-oriented optical data storage *** parameters are optimized to achieve large channel *** 8:16 modulation code is designed to reduce the raw bit error rate and its performances are experimentally evaluated.A raw bit error rate of the magnitude of 10 4 is obtained with a single-data-page storage and 10 3 with multiplexing.

关键词： Volume holographic data storage Modulation codes Sparse codes Raw bit error rate Channel capacity

A novel chemosensor-bipyridyl end capped hyperbranched conjugated polymer

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Chinese Chemical Letters 2011年第6期22卷 725-728页

作者： Xin Meng qing guo he Hui Min Cao Jian Gong Cheng State Key Laboratory of Transducer Technology Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China

A novel hyperbranched conjugated chemosensor with bipyridyl groups as periphery groups（BPY-HPV） was ***-HPV was highly sensitive to metal ions（Cu^（2＋）,Ni^（2＋）） for the strong coordination interaction（K_（sv） at the order of 10~7 mol^（-1） L） monitored by fluorescence ***,by hydrogen bonds and charge transfer interaction,BPY-HPV shows strong interaction with 1,1,2,2-tetrachloroethane whatever in CH_2Cl_2（K_（sv）～10~6 mol^（-1） L） or film.

关键词： Hyperbranched conjugated polymer Hydrogen bonding Fluorescence Tetrachloroethane

Optimization of biotransformation from phytosterol to androstenedione by a mutant Mycobacterium neoaurum ZJUVN-08

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2013年第2期14卷 132-143页

作者： Xiao-yan ZHANG Yong PENG Zhong-rui SU Qi-he CheN Hui RUAN guo-qing he Department of Food Science and Nutrition Zhejiang University Department of Food Science and Technology School of Agriculture and BiologyShanghai Jiao Tong University

Biotransformation of phytosterol(PS) by a newly isolated mutant Mycobacterium neoaurum ZJUVN-08 to produce androstenedione has been investigated in this *** parameters of the biotransformation process were optimized using fractional factorial design and response surface *** was the sole product in the fermentation broth catalyzed by the mutant *** ZJUVN-08 *** showed that molar ratio of hydroxypropyl-β-cyclodextrin(HP-β-CD) to PS and substrate concentrations were the two most significant factors affecting androstenedione *** analyzing the statistical model of three-dimensional surface plot,the optimal process conditions were observed at 0.1 g/L inducer,pH 7.0,molar ratio of HP-β-CD to PS 1.92:1,8.98 g/L PS,and at 120 h of incubation *** these conditions,the maximum androstenedione yield was 5.96 g/L and nearly the same with the non-optimized(5.99 g/L),while the maximum PS conversion rate was 94.69% which increased by 10.66% compared with the non-optimized(84.03%).The predicted optimum conditions from the mathematical model were in agreement with the verification experimental *** is considered that response surface methodology was a powerful and efficient method to optimize the parameters of PS biotransformation process.

关键词： Phytosterol Mycobacterium neoaurum ZJUVN-08 Androstenedione Hydroxypropyl-β-cyclodextrin

Effects of proteinase A on cultivation and viability characteristics of industrial Saccharomyces cerevisiae WZ65

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第10期10卷 769-776页

作者： Hong-bo ZHANG Hai-feng ZHANG Qi-he CheN Hui RUAN Ming-liang FU guo-qing he Department of Food Science and Nutrition Zhejiang University Hangzhou 310029 China

Proteinase A （PrA）, encoded by PEP4 gene, is a key enzyme in the vacuoles of Saccharomyces cerevisiae. We characterized the effects of PrA on cell growth and glucose metabolism in the industrial S. cerevisiae WZ65. It was observed that the lag phase of cell growth of partial PEP4 gene deletion mutant （36 h） and PrA-negative mutant （48 h） was significantly extended, compared with the wild type strain （24 h）（P〈0.05）, but PrA had no effect on glucose metabolism either under shaking or steady state cultivations. The logistic model was chosen to evaluate the effect of PrA on S. cerevisiae cell growth, and PrA was found to promote cell growth against insufficient oxygen condition in steady state cultivation, but had no effect in shaking cultivation. The effects of glucose starvation on cell growth of partial PEP4 gene deletion strain and PrA-negative mutant were also evaluated. The results show that PrA partial deficiency increased the adaption ofS. cerevisiae to unfavorable nutrient environment, but had no effect on glucose metabolism under the stress of low glucose. During heat shock test, at 60 ℃ the reduced cell viability rate （RCVR） was 10% for the wild type S. cerevisiae and 90% for both mutant strains （P〈0.01）, suggesting that PrA was a negative factor for S. cerevisiae cells to survive under heat shock. As temperatures rose from 60 ℃ to 70℃, the wild type S. cerevisiae had significantly lower relative glucose consumption rate （RGCR）（61.0% and 80.0%） than the partial mutant （78.0% and 98.5%） and the complete mutant （80.0% and 98.0%）（P〈0.05）, suggesting that, in coping with heat shock, cells of the PrA mutants increased their glucose consumption to survive. The present study may provide meaningful information for brewing industry; however, the role of PrA in industrial S. cerevisiae physiology is complex and needs to be further investigated.

关键词： Proteinase A (PrA) PEP4 gene Saccharomyces cerevisiae WZ65 Cell metabolism Viability

Construction of recombinant industrial Saccharomyces cerevisiae strain with bglS gene insertion into PEP4 locus by homologous recombination

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第7期9卷 527-535页

作者： Qiang ZHANG Qi-he CheN Ming-liang FU Jin-ling WANG Hong-bo ZHANG guo-qing he Department of Food Science and Nutrition Zhejiang University Hangzhou 310029 China

The bglS gene encoding endo-1,3-1,4-β-glucanase from Bacillus subtil＆ was cloned and sequenced in this study. The bglS expression cassette, including PGK1 promoter, bglS gene fused to the signal sequence of the yeast mating pheromone a-factor （MFals）, and ADH1 terminator with G418-resistance as the selected marker, was constructed. Then one of the PEP4 allele of Saccharomyces cerevisiae WZ65 strain was replaced by bglS expression cassette using chromosomal integration of polymerase chain reaction （PCR）-mediated homologous recombination, and the bglS gene was expressed simultaneously. The recombinant strain S. cerevisiae （SC-βG） was preliminarily screened by the clearing hydrolysis zone formed after the barley β-glucan was hydrolyzed in the plate and no proteinase A （PrA） activity was measured in fermenting liquor. The results of PCR analysis of genome DNA showed that one of the PEP4 allele had been replaced and bglS gene had been inserted into the locus of PEP4 gene in recombinant strains. Different endo-1,3-1,4-β-glucanase assay methods showed that the recombinant strain SC-βG had high endo-1,3-1,4-β-glucanase expression level with the maximum of 69.3 U/（h·ml） after 60 h of incubation. Meanwhile, the Congo Red method was suitable for the determination of endo-1,3-1,4-β-glucanase activity during the actual brewing process. The current research implies that the constructed yeast strain could be utilized to improve the industrial brewing property of beer.

关键词： Endo-1 3-1 4-β-glucanase (bglS) Gene replacement Homologous recombination Bacillus subtilis PEP4 gene Saccharomyces cerevisiae

Study on swelling model and thermodynamic structure of native konjac glucomannan

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第4期10卷 273-279页

作者： Long LI Hui RUAN Liu-liu MA Wei WANG Ping ZHOU guo-qing he Department of Food Science and Nutrition College of Biosystem Engineering and Food Science Zhejiang University Hangzhou 310029 China Department of Food Science and Technology Guangdong Shaoguan College Shaoguan 512005 China

We investigated the higher structure of konjac glucomannan (KGM) in the amorphous state and solution using a laser particle size analyzer and a water activity meter. The results show that the thermodynamic structures of native KGM were primarily composed of the lamella structure units, which involve both granular crystalline and amorphous regions, and that the connection zones of such units contained both loose and tight aggregation regions. The value of surface tension (σ) of native KGM, resting with the density of its hydroxyl groups' self-association, was an important parameter to analyze the higher structures of native KGM in the thermodynamic swelling model of native KGM.

关键词： Swelling model Thermodynamic structure Konjac glucomannan (KGM) Higher structure

Construction of the yeast whole-cell Rhizopus oryzae lipase biocatalyst with high activity

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第7期12卷 545-551页

作者： Mei-ling CheN Qin guo Rui-zhi WANG Juan XU Chen-wei ZHOU Hui RUAN guo-qing he Department of Food Science and Nutrition Zhejiang University Hangzhou 310029 China School of Food and Biological Engineering Jiangsu University Zhenjiang 212013 China

Surface display is effectively utilized to construct a whole-cell *** optimization has been proven to be effective in maximizing production of heterologous proteins in ***,the cDNA sequence of Rhizopus oryzae lipase (ROL) was optimized and synthesized according to the codon bias of Saccharomyces cerevisiae,and based on the Saccharomyces cerevisiae cell surface display system with α-agglutinin as an anchor,recombinant yeast displaying fully codon-optimized ROL with high activity was successfully *** with the wild-type ROL-displaying yeast,the activity of the codon-optimized ROL yeast whole-cell biocatalyst (25 U/g dried cells) was 12.8-fold higher in a hydrolysis reaction using p-nitrophenyl palmitate (pNPP) as the *** our knowledge,this was the first attempt to combine the techniques of yeast surface display and codon optimization for whole-cell biocatalyst ***,the yeast whole-cell ROL biocatalyst was constructed with high *** optimum pH and temperature for the yeast whole-cell ROL biocatalyst were pH 7.0 and 40 °***,this whole-cell biocatalyst was applied to the hydrolysis of tributyrin and the resulted conversion of butyric acid reached 96.91% after 144 h.

关键词： Rhizopus oryzae lipase (ROL) Yeast surface display Codon optimization Whole-cell biocatalyst