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A novel environmental friendly plasticizer (TPE) derived from tung oil fatty acid with long fatty acid chain and high degree of branching was synthesized. Chemical structure of the obtained TPE was characterized with Fourier transform infrared spectroscopy (FT-IR) and 1H NMR. TPE was used to prepare plasticized PVC blends as main plasticizer. Thermal stability, mechanical properties and migration resistance of poly (vinyl chloride) plasticized with TPE were investigated. The results showed that torque data of plasticized PVC blends reached 12.4 N·m when the mass of the TPE was 50 wt.%. TPE improved the thermal stability of PVC blends obviously than dioctyl phthalate (DOP). The leaching tests showed that PVC plasticized with TPE were with higher migration resistance than that of DOP. The excellent thermal stability and high migration resistance of PVC blends showed high application value for TPE.

As a substitute sweetener for sucrose, d‐tagatose is widely used in products, such as health drinks, yogurt, fruit juices, baked goods, confectionery, and pharmaceutical preparations. In the fermentation process of l‐AI produced by Lactobacillus plantarum, d‐tagatose is produced through biotransformation and this study was based on the fermentation process of Lactobacillus plantarum WU14 producing l‐AI to further research the biotransformation and separation process of d‐tagatose. The kinetics of cell growth, substrate consumption, and l‐arabinose isomerase formation were established by nonlinear fitting, and the fitting degrees were 0.996, 0.994, and 0.991, respectively, which could better reflect the change rule of d‐tagatose biotransformation in the fermentation process of L. plantarum WU14. The separation process of d‐tagatose was identified by decolorization, protein removal, desalination, and freeze drying, initially. Finally, the volume ratio of whole cell catalysts, d‐galactose, and borate was 5:1:2 at 60°C, pH 7.17 through borate complexation; then, after 24 hr of conversion, the yield of d‐tagatose was 58 g/L. [ABSTRACT FROM AUTHOR]

Glucose isomerase (GI) that catalyzes the conversion of D-glucose to D-fructose is one of the most important industrial enzymes for the production of high-fructose corn syrup (HFCS). In this study, a novel GI (CbGI) was cloned from Caldicellulosiruptor bescii and expressed in Escherichia coli. The purified recombinant CbGI (rCbGI) showed neutral and thermophilic properties. It had optimal activities at pH 7.0 and 80°C and retained stability at 85°C. In comparison with other reported GIs, rCbGI exhibited higher substrate affinity (K m = 42.61 mM) and greater conversion efficiency (up to 57.3% with 3M D-glucose as the substrate). The high catalytic efficiency and affinity of this CbGI is much valuable for the cost-effective production of HFCS. [ABSTRACT FROM AUTHOR]

In this study, bio‐based hyperbranched ester was synthesized from castor oil. The chemical structure of the bio‐based hyperbranched ester obtained was characterized with Fourier transform infrared and 1H NMR spectra. Soft polyvinyl chloride (PVC) materials were prepared via thermoplastic blending at 160 °C using bio‐based hyperbranched ester as plasticizer. The performances including the thermal stability, glass transition temperature (Tg), crystallinity, tensile properties, solvent extraction resistance and volatility resistance of soft PVC materials incorporating bio‐based hyperbranched ester were investigated and compared with the traditional plasticizer dioctyl phthalate (DOP). The results showed that bio‐based hyperbranched ester enhanced the thermal stability of the PVC materials. The Tg of PVC incorporating bio‐based hyperbranched ester was 23 °C, lower than that of PVC/DOP materials at 28 °C. Bio‐based hyperbranched ester showed a better plasticizing effect, solvent extraction resistance and volatility resistance than DOP. The plasticizing mechanism is also discussed. © 2018 Society of Chemical Industry We synthesized a kind of bio‐based hyperbranched ester using castor oil as raw material. Soft polyvinyl chloride (PVC) materials were prepared via thermoplastic blending using bio‐based hyperbranched ester as plasticizer. The soft PVC materials obtained showed improved thermal stability and mechanical properties and better solvent extraction resistance and volatility resistance than dioctyl phthalate. [ABSTRACT FROM AUTHOR]