1.Research process of the preparation of electrostatic spinning of poly-glycerol sebacate and the application in tissue engineering.
West China Journal of Stomatology 2015;33(5):539-542
Poly-glycerol sebacate (PGS) is a novel biodegradable elastomer, it has been widely applied in the biomedical fields of heart, blood vessel and cartilage owing to its excellent biological performance, mechanical property and degradability. Electrostatic spinning is a preparation method of tissue engineering scaffolds with the characteristics of convenience, processing controllability and cost efficiency. In this paper, the author reviewed the research process of electrostatic spinning preparation and the application in the field of tissue engineering.
Decanoates
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chemistry
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Elastomers
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Glycerol
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analogs & derivatives
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chemistry
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Humans
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Polymers
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chemistry
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Tissue Engineering
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methods
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Tissue Scaffolds
2.Construction and optimization of Escherichia coli for producing rhamnolipid biosurfactant.
Zhijin GONG ; Yanfeng PENG ; Yuting ZHANG ; Guotian SONG ; Wujiu CHEN ; Shiru JIA ; Qinhong WANG
Chinese Journal of Biotechnology 2015;31(7):1050-1062
Rhamnolipid biosurfactant is mainly produced by Pseudomonas aeruginosa that is the opportunistic pathogenic strain and not suitable for future industrial development. In order to develop a relatively safe microbial strain for the production of rhamnolipid biosurfactant, we constructed engineered Escherichia coli strains for rhamnolipid production by expressing different copy numbers of rhamnosyltransferase (rhlAB) gene with the constitutive synthetic promoters of different strengths in E. coli ATCC 8739. We further studied the combinatorial regulation of rhlAB gene and rhaBDAC gene cluster for dTDP-1-rhamnose biosynthesis with different synthetic promoters, and obtained the best engineered strain-E. coli TIB-RAB226. Through the optimization of culture temperature, the titer of rhamnolipd reached 124.3 mg/L, 1.17 fold higher than that under the original condition. Fed-batch fermentation further improved the production of rhamnolipid and the titer reached the highest 209.2 mg/L within 12 h. High performance liquid chromatography-mass spectrometry (LC-MS) analysis showed that there are total 5 mono-rhamnolipid congeners with different nuclear mass ratio and relative abundance. This study laid foundation for heterologous biosynthesis of rhanomilipd.
Bacterial Proteins
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genetics
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Batch Cell Culture Techniques
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Decanoates
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Escherichia coli
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metabolism
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Fermentation
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Glycolipids
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biosynthesis
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Hexosyltransferases
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genetics
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Industrial Microbiology
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methods
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Multigene Family
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Promoter Regions, Genetic
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Pseudomonas aeruginosa
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Rhamnose
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analogs & derivatives
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biosynthesis
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Surface-Active Agents
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metabolism