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Impact of Leucine 278 Residue on Fatty Acid Length Specificity of <i>Candida antarctica</i>Lipase B

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Advances in Microbiology 2015年第7期5卷 493-499页

作者： Fanghua Wang Shulin Hou Qian Wang Pu Wang Jinsong Liu Bo Yang Yonghua Wang College of Light Industry and food Sciences South China University of Technology Guangzhou China State Key Laboratory of Respiratory Disease Guangzhou Institutes of Biomedicine and Health Chinese Academy of Sciences Guangzhou China School of Bioscience and Bioengineering South China University of Technology Guangzhou China

Structural analysis of Candida antarctica lipase B (CALB) indicates that side chain of leucine at 278 site lies above the entrance of the catalytic pocket, which prognosticates its potential role on substrate specificity of the enzyme. To verify this presumption, shortened side chain of glycine or proline was rational designed and mutants were constructed by site-directed mutagenesis method. The colorimetric assay using p-nitrophenyl esters of fatty acids with various chain-lengths was used to study the substrate preference of lipases. Results indicated that L278G or L278P mutations both induced the drift of substrate specificity of CALB from p-nitrophenyl caprylate (pNP-C8) to longer carbon chain length of p-nitrophenyl caprate (pNP-C10). Meanwhile, Vmax value of two mutants to pNP-C10 was both higher than that of wild-type. Docking results also indicated that shortened side chain of glycine or proline residues substitution at this site could get rid of the space block present above the catalytic pocket, and made longer chain substrate (pNP-C10) enter into the catalytic pocket easier. The modulation of specificity observed allowed for building substrate binding model and opened new possibilities for designing ligand specific lipases.

关键词： Candida antarctica Lipase B (CALB) Site-Directed Mutagenesis Substrate Specificity Stereospecific Blockade

Conversion of acetate and glyoxylate to fumarate by a cell-free synthetic enzymatic biosystem

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Synthetic and Systems Biotechnology 2023年第2期8卷 235-241页

作者： Congli Hou Linyue Tian Guoli Lian Li-Hai Fan Zheng-Jun Li College of Chemical Engineering Fujian Engineering Research Center of Advanced Manufacturing Technology for Fine ChemicalsFuzhou UniversityFuzhou350108People’s Republic of China College of Life Science and technology Beijing University of Chemical TechnologyBeijing100029People’s Republic of China Qingyuan Innovation Laboratory Quanzhou362801People’s Republic of China

Fumarate is a value-added chemical that is widely used in food,medicine,material,and agriculture *** the rising attention to the demand for fumarate and sustainable development,many novel alternative ways that can replace the traditional petrochemical routes *** in vitro cell-free multi-enzyme catalysis is an effective method to produce high value *** this study,a multi-enzyme catalytic pathway comprising three enzymes for fumarate production from low-cost substrates acetate and glyoxylate was *** acetyl-CoA synthase,malate synthase,and fumarase from Escherichia coli were selected and the coenzyme A achieved *** enzymatic properties and optimization of reaction system were investigated,reaching a fumarate yield of 0.34 mM with a conversion rate of 34%after 20 h of *** proposed and realized the conversion of acetate and glyoxylate to fumarate in vitro using a cell-free multi-enzyme catalytic system,thus providing an alternative approach for the production of fumarate.

关键词： Fumarate Cell-free Multi-enzyme catalysis Acetate Glyoxylate

Nutritional, Textural, Sensory Properties and Storage Stability Evaluation of Newly Formulated Strawberry Bar

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food and Nutrition Sciences 2023年第4期14卷 287-299页

作者： Nargis Akter Md. Sajib Al Reza Md. Esrafil Md. Al Amin Sonyia Akter Neaz Morshed Reza Md. Nazmul Huda Nasim Pratima Roy Dina Department of food technology and Nutritional Science Faculty of Life Science Mawlana Bhashani Science and Technology University Santosh Bangladesh Department of Biological Sciences Graduate School of Science Tokyo Metropolitan University Hachioji Japan Department of Chemistry and Biochemistry The University of Texas at Arlington Arlington USA

An analytical study was conducted to develop a strawberry bar and analysis of the nutritional quality and storage stability of a newly formulated strawberry bar. In proximate analysis moisture, ash, pH, acidity, vitamin C, total phenolic content, and antioxidant of strawberry pulp were found 82%, 0.5%, 2.57, 1.38%, 49 mg/100g, 0.33%, 75.17% whereas, in the strawberry bar, it was found 18%, 0.71%, 2.10, 1.10%, 22 mg/100g, 0.14%, 56.13% respectively. For textural properties analysis, the textural profile of the strawberry bar such as hardness, factorability, viscosity, cohesiveness, adhesiveness, springiness, gumminess, chewiness, probe diameter, threshold, filtering range of strawberry bar was found 5.538 × 104 N/m, 0.000 N/m2, 1.687 × 104 N/m2, 0.6636, 2.908 × 103 J/m3, 0.8664, 3.675 × 104 N/m2, 3.184 × 104 N/m2, 20.000 mm, 5 N, 0.4 N respectively whereas the maximum level was 17.4 N at 29.628 seconds and the minimum level was -5.3 N at 30.166 seconds. The sensory evaluation of the strawberry bar was conducted based on nine-point hedonic scales. The sensory evaluation results indicated that the appearance of the strawberry bar was liked very much and the taste, texture, color, aroma, and overall acceptability of the strawberry bar were liked moderately by panelists. In microbiological analysis, the Total Viable Count (TVC) and Total Coliform Count (TCC) of the strawberry bar were found safe levels for up to third days. But on the sixth day, the TCC of the strawberry bar was not found and the TVC of the strawberry bar was found 17 × 104 cfu/g respectively which is higher than the permitted value (Gulf Standard: 105 cfu/g). From the microbial point of view, the newly formulated strawberry bar was safe to consume for up to 3 days but not for 6 days.

关键词： Strawberry Pulp Strawberry Bar Antioxidant Sensory Evaluation Texture Gallic Acid

Valuable Biomolecules from Nine North Atlantic Red Macroalgae: Amino Acids, Fatty Acids, Carotenoids, Minerals and Metals

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Natural Resources 2016年第4期7卷 157-183页

作者： Behnaz Razi Parjikolaei Annette Bruhn Karin Loft Eybye Martin Mørk Larsen Michael Bo Rasmussen Knud Villy Christensen Xavier C. Fretté Department of Chemical Engineering Biotechnology and Environmental Technology University of Southern Denmark Odense Denmark Department of Bioscience Aarhus University Silkeborg Denmark food technology Department Life Science Division Danish Technological Institute Aarhus Denmark Department of Bioscience Aarhus University Roskilde Denmark

In modern society, novel marine resources are scrutinized pursuing compounds of use in the medical, pharmaceutical, biotech, food or feed industry. Few of the numerous marine macroalgae are currently exploited. In this study, the contents of nutritional compounds from nine common North Atlantic red macroalgae were compared: the lipid content was low and constant among the species, whereas the fatty acid profiles indicated that these species constitute interesting sources of polyunsaturated fatty acids (PUFA). The dominating essential and non-essential amino acids were lysine and leucine, aspartic acid, glutamic acid, and arginine, respectively. The amino acid score of the nine algae varied from 44% to 92%, the most commonly first limiting amino acid being histidine. Lutein, β-carotene, and zeaxanthin were the identified carotenoids. Contents of all macro and trace minerals, with the exception of phosphorus, were higher than those described for conventional food. Low sodium/potassium ratios (0.08 - 2.54) suggested a potential for using the ash fraction for sodium salt replacement. The algae constituted rich sources of carbohydrates (40% to 71% of DM) which show their potential for a broader commercial exploitation. In some species, the concentrations of arsenic, cadmium, and lead exceeded limit values for application in food or feed. In conclusion, the nine algae represent promising potential sources of health promoting additives for human and animal diets, in whole or in a biorefinery concept.

关键词： Protein Lipid Carotenoids Dry Matter Arsenic

Fine-tune chiroptical activity in discrete chiral Au nanorods

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Nano Research 2022年第7期15卷 6574-6581页

作者： Guangchao Zheng Sulin Jiao Wei Zhang Shenli Wang Qinghua Zhang Lin Gu Weixiang Ye Junjun Li Xiaochen Ren Zhicheng Zhang Kwok-yin Wong School of Physics and Microelectronics Zhengzhou UniversityZhengzhou 450001China State Key Laboratory of Chemical Biology and Drug Discovery Department of Applied Biology and Chemical TechnologyThe Hong Kong Polytechnic UniversityKowloonHong KongChina Institute of Applied Physics and Computational Mathematics Beijing 100088China School of food Science and Engineering Henan University of TechnologyZhengzhou 450001China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China Department of Applied Physics School of ScienceHainan UniversityHaikou 570228China Tianjin Key Laboratory of Molecular Optoelectronic Sciences Department of ChemistrySchool of ScienceTianjin University&Collaborative Innovation Center of Chemical Science and EngineeringTianjin 300072China

Accurate researches on the surface plasmon resonance(SPR)-based applications of chiral plasmonic metal nanoparticles(NPs)still remain a great ***,a series of chiral plasmonic metal NPs,e.g.,chiral Au nanorods(c-Au NRs),c-Au@Ag core–shell,and c-Au@TiO_(2) core–shell NRs,with different chiroptical activities have been *** circular dichroism(PCD)bands of c-Au NRs can be precisely tailored by tuning the longitudinal SPR(LSPR)and amount of Au NRs as ***,a shift of PCD bands within ultraviolet–visible–near infrared ray(UV–vis–NIR)region can also be achieved through the functionalization of a shell of another metal or ***,chirality transfer from c-Au core to Ag shell leads to new PCD bands at the near-UV *** tuning of PCD bands and chirality transfer are confirmed by our developed theoretical *** chiral Au NRs-based chiral plasmonic nanomaterials with tunable chiroptical activities will be helpful to understand the structure-direct PCD and to extend circularly polarized-based applications.

关键词： chiral Au nanorods(c-Au NRs) surface plasmon resonance optical activity chirality transfer

Interfacial synthesis of crystalline quasi-two-dimensional polyaniline thin films for high-performance flexible on-chip micro-supercapacitors

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Chinese Chemical Letters 2022年第8期33卷 3921-3924页

作者： Tao Zhang Panpan Zhang Zhongquan Liao Faxing Wang Jinhui Wang Mingchao Wang Ehrenfried Zschech Xiaodong Zhuang Oliver G.Schmidt Xinliang Feng Key Laboratory of Bio-based Polymeric Materials technology and Application of Zhejiang Province Ningbo Institute of Material Technology and EngineeringChinese Academy of SciencesNingbo 315201China Faculty of Chemistry and food Chemistry Technische Universität DresdenDresden 01062Germany Center for Advancing Electronics Dresden(cfaed) Technische Universität DresdenDresden 01062Germany Fraunhofer Institute for Ceramic Technologies and Systems(IKTS) Dresden 01109Germany Material Systems for Nanoelectronics Chemnitz University of TechnologyChemnitz 09107Germany Institute for Integrative Nanosciences IFW DresdenDresden 01069Germany School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative MoleculesShanghai Jiao Tong UniversityShanghai 200240China Key Laboratory for Special Functional Materials of Ministry of Education Henan UniversityKaifeng 475004China

Quasi-two-dimensional(q2 D)conducting polymer thin film synergizes the advantageous features of longrange molecular ordering and high intrinsic conductivity,which are promising for flexible thin film-based micro-supercapacitors(MSCs).Herein,we present the high-performance flexible MSCs based on highly ordered quasi-two-dimensional polyaniline(q2 D-PANI)thin film using surfactant monolayer assisted interfacial synthesis(SMAIS).Owing to high electrical conductivity,rich redox chemistry,and thin-film morphology,the q2 D-PANI MSCs show high volumetric specific capacitance(ca.360 F/cm^(3))and energy density(17.9 m Wh/cm^(3)),which outperform the state-of-art PANI thin-film based MSCs and promise for future flexible electronics.

关键词： 2D polymers Conducting polymers Interfacial synthesis Flexible electronics Microsupercapacitor

Immunity-and-matrix-regulatory cells enhance cartilage regeneration for meniscus injuries: a phase I dose-escalation trial

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Signal Transduction and Targeted Therapy 2023年第12期8卷 5873-5886页

作者： Liangjiang Huang Song Zhang Jun Wu Baojie Guo Tingting Gao Sayed Zulfiqar Ali Shah Bo Huang Yajie Li Bo Zhu Jiaqi Fan Liu Wang Yani Xiao Wenjing Liu Yao Tian Zhengyu Fang Yingying Lv Lingfeng Xie Sheng Yao Gaotan Ke Xiaolin Huang Ying Huang Yujuan Li Yi Jia Zhongwen Li Guihai Feng Yan Huo Wei Li Qi Zhou Jie Hao Baoyang Hu Hong Chen Department of Rehabilitation Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina National Stem Cell Resource Center State Key Laboratory of Stem Cell and Reproductive BiologyInstitute of ZoologyInstitute for Stem Cell and RegenerationChinese Academy of SciencesBeijingChina Beijing Institute for Stem Cell and Regenerative Medicine BeijingChina Department of Radiology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina Stem Cell Research Center Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina Department of Orthopedics Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina University of Chinese Academy of Sciences BeijingChina Beijing Key Lab for Pre-clinical Safety Evaluation of Drugs National Center for Safety Evaluation of DrugsNational Institutes for Food and Drug ControlBeijingChina Beijing Zephyrm Biotechnologies Co. Ltd.BeijingChina

Immunity-and-matrix-regulatory cells(IMRCs)derived from human embryonic stem cells have unique abilities in modulating immunity and regulating the extracellular matrix,which could be mass-produced with stable biological *** resemblance to mesenchymal stem cells(MSCs)in terms of self-renew and tri-lineage differentiation,the ability of IMRCs to repair the meniscus and the underlying mechanism remains ***,we showed that IMRCs demonstrated stronger immunomodulatory and pro-regenerative potential than umbilical cord MSCs when stimulated by synovial fluid from patients with meniscus *** injection into the knees of rabbits with meniscal injury,IMRCs enhanced endogenous fibrocartilage *** the dose-escalating phase I clinical trial(NCT03839238)with eighteen patients recruited,we found that intra-articular IMRCs injection in patients was safe over 12 months ***,the effective results of magnetic resonance imaging(MRI)of meniscus repair and knee functional scores suggested that 5×107 cells are optimal for meniscus injury *** summary,we present the first report of a phase I clinical trial using IMRCs to treat meniscus *** results demonstrated that intra-articular injection of IMRCs is a safe and effective therapy by providing a permissive niche for cartilage regeneration.

关键词： meniscus injuries cartilage

Development of a triple channel detection probe for hydrogen peroxide

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Chinese Chemical Letters 2015年第12期26卷 1465-1469页

作者： Wen-Zhu Zhang Zhong-Bo Du Bo Song Zhi-Qiang Ye Jing-Li Yuan State Key Laboratory of Fine Chemicals School of Chemistry Dalian University of Technology

The rapid and reliable measurement of hydrogen peroxide（H_2O_2） is imperative for many areas of technology, including pharmaceutical, clinical, food industry and environmental applications. In this work, a novel multifunctional complex, [Ru（bpy）_2（luminol-bpy）]（PF_6）_2（bpy： 2,20-bipyridine）, was designed and synthesized by incorporating a Ru（II） complex with a luminal group. In the presence of horseradish peroxidase（HRP）, reaction of [Ru（bpy）_2（luminol-bpy）]_2＋with H_2O_2 can be monitored by three sensing channels including photoluminescence（PL）, chemiluminiscence（CL） and eletrochemiluminiscence（ECL）. The quantitative assays for H_2O_2 in aqueous solutions using [Ru（bpy）_2（Luminalbpy）]（PF_6）_2as a probe were established with PL, ECL and CL signal output modes, respectively.

关键词： triple peroxide luminal peroxidase bipyridine monitored pharmaceutical spectrometer purchased reversible

Greenhouse gas emissions from pig and poultry production sectors in China from 1960 to 2010

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Journal of Integrative Agriculture 2017年第1期16卷 221-228页

作者： WANG Li-zhi XUE Bai Tianhai Yan Animal Nutrition Institute Sichuan Agricultural University Ya'an 625014 P.R. China Agri-food and Biosciences Institute Co. Down BT26 6DR United Kingdom

Pig and poultry production in China had experienced considerable changes from 1960 to 2010. The present study aimed to evaluate the effects of these changes on greenhouse gas emission inventeries （expressed as CO2 equivalent） from these two sectors. The inventories included methane emissions from enteric fermentation, methane and nitrous oxide production from manure management. The greenhouse gas emissions from these sources in 2010 in pig sector were 17, 62 and 21%, respectively, and that in poultry sector （including chicken, duck, goose and others） were 1, 18 and 81%, respectively. Total CO2 equivalent increased from 1960 to 2010 in both pig （11 582 to 55564 Gg yr-1） and poultry （1 497 to 14 873 Gg yr-1） sectors. Within poultry sector, emissions from chicken, duck, goose and others accounted for 74, 15, 11 and 0.01% in 2010, respectively. However, during the last 50 years, these emissions continuously reduced when related to production of I kg of pork （8.01 to 1.14 kg kg-1）, poultry meat （1.19 to 0.37 kg kg-1） and egg （0.47 to 0.33 kg kg-1）, which is mainly associated with the continuous improvement in production efficiency in all management systems. These results provide benchmark information for Chinese authorities to develop appropriate policies and mitigation strategies to reduce greenhouse gas emissions from pig and poultry sectors.

关键词： China greenhouse gas inventory pig poultry