Publications by authors named "Junfeng Cheng"

16 Publications

  • Page 1 of 1

Functional effectiveness of double essential [email protected] starch/microcrystalline cellulose as active antibacterial packaging.

Int J Biol Macromol 2021 Sep 19;186:873-885. Epub 2021 Jul 19.

School of Food and Biological Engineering, Hefei University of Technology, 230009 Hefei, Anhui, PR China; Anhui Institute of Agro-Products Intensive Processing Technology, 230009 Hefei, Anhui, PR China.

In this work, two combinations of double EOs, i.e., α-terpineol: eugenol (α-T:Eu) and carvacrol:eugenol (CA:Eu), are used to develop the active antibacterial films of double [email protected] starch/microcrystalline cellulose ([email protected]). The hydrogen-bonded networks in SC matrix are conducive to thermostability enhancement and the film of SC25 is determined for EO incorporation. The interactions between EOs and SC matrix are also hydrogen bonds and the double [email protected] are smooth at ratio of ≤2:2 for α-T:Eu or CA:Eu. The ultimate film properties are dependent on the incorporated EOs. The release of EOs is well controlled by two mechanisms of diffusion (predominant) and swelling (secondary). Synergetic antibacterial activity occurs on double [email protected] The shelf life of pork can be extended by 1 day at 25 °C by the two typical films of α-T:[email protected] and CA:[email protected] Moreover, [email protected] can be well degraded in humus soil. Thereby, the target films will have great potential in active packaging to extend the shelf life of food.
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http://dx.doi.org/10.1016/j.ijbiomac.2021.07.094DOI Listing
September 2021

Preparation and Laser Marking Properties of Poly(propylene)/Molybdenum Sulfide Composite Materials.

ACS Omega 2021 Apr 25;6(13):9129-9140. Epub 2021 Mar 25.

School of Materials Engineering, Changshu Institute of Technology, Changshu, Jiangsu 215500, P. R. China.

In this study, using molybdenum sulfide (MoS) as laser-sensitive particles and poly(propylene) (PP) as the matrix resin, laser-markable PP/MoS composite materials with different MoS contents ranging from 0.005 to 0.2% were prepared by melt-blending. A comprehensive analysis of the laser marking performance of PP/MoS composites was carried out by controlling the content of laser additives, laser current intensity, and the scanning speed of laser marking. The color difference test shows that the best laser marking performance of the composite can be obtained at the MoS content of 0.02 wt %. The surface morphology of the PP/MoS composite material was observed after laser marking using a metallographic microscope, an optical microscope, and a scanning electron microscope (SEM). During the laser marking process, the laser energy was absorbed and converted into heat energy to cause high-temperature melting, pyrolysis, and carbonization of PP on the surface of the PP/MoS composite material. The black marking from carbonized materials was formed in contrast to the white matrix. Using X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, and Raman spectroscopy, the composite materials before and after laser marking were tested and characterized. The PP/MoS composite material was pyrolyzed to form amorphous carbonized materials. The effect of the laser-sensitive MoS additive on the mechanical properties of composite materials was investigated. The results show that the PP/MoS composite has the best laser marking property when the MoS loading content is 0.02 wt %, the laser marking current intensity is 11 A, and the laser marking speed is 800 mm/s, leading to a clear and high-contrast marking pattern.
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http://dx.doi.org/10.1021/acsomega.1c00255DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8028170PMC
April 2021

Construction of Self-Assembled Polyelectrolyte/Cationic Microgel Multilayers and Their Interaction with Anionic Dyes Using Quartz Crystal Microbalance and Atomic Force Microscopy.

ACS Omega 2021 Mar 15;6(8):5764-5774. Epub 2021 Feb 15.

Key Laboratory of Optic-electric Sensing and Analytical Chemistry for Life Science, MOE; College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, No. 53 Zhengzhou Road, Qingdao 266042, P. R. China.

This study aimed to reveal the interaction between self-assembled multilayers and dye molecules in the environment, which is closely related to the multilayers' stable performance and service life. In this work, the pH-responsive poly (-isopropylacrylamide--2-(dimethylamino) ethyl methacrylate) microgels were prepared by free-radical copolymerization and self-assembled with sodium alginate (SA) into multilayers by the layer-by-layer deposition method. Quartz crystal microbalance (QCM) and atomic force microscopy (AFM) results confirmed the construction of multilayers and the absorbed mass, resulting in a decrease in the frequency shift of the QCM sensor and the deposition of microgel particles on its surface. The interaction between the self-assembled SA/microgel multilayers and anionic dyes in the aqueous solution was further investigated by QCM, and it was found that the electrostatic attraction between dyes and microgels deposited on the QCM sensor surface was much larger than that of the microgels with SA in multilayers, leading to the release of the microgels from the self-assembled structure and a mass loss ratio of 27.6%. AFM observation of the multilayer morphology exposed to dyes showed that 29% of the microgels was peeled off, and the corresponding microgel imprints were generated on the surface. In contrast, the shape and size of the remaining self-assembled microgel particles did not change.
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http://dx.doi.org/10.1021/acsomega.0c06181DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7931438PMC
March 2021

Laser irradiation method to prepare polyethylene porous fiber membrane with ultrahigh xylene gas filtration capacity.

J Hazard Mater 2021 04 9;407:124395. Epub 2020 Nov 9.

Key Laboratory of Advanced Civil Engineering Materials, School of Materials Science & Engineering, Tongji University, Shanghai 201804, China. Electronic address:

In recent years, volatile organic compound (VOC) gases have caused potential harm to people's health. This study reveals the preparation of polyethylene porous fiber membrane with excellent low-concentration VOCs filtration performance via laser irradiation technology. A neodymium-doped yttrium aluminum garnet (Nd:YAG) pulsed laser beam was used to scan the laser-sensitive low-density polyethylene/carbon black (LDPE/CB) fibers prepared by nanolayer coextrusion in the air. The controllable thermal energy generated by laser irradiation makes the surface of the fiber membrane to produce a porous carbon layer in situ. Laser power and scanning speed are important parameters for controlling laser-induced carbonization. The results indicate that the rich "fluffy" carbon structures on the surface of the porous fiber membrane can efficiently adsorb xylene gas. This study can provide a positive reference for the large-scale preparation of polyolefin porous fiber membrane with VOCs filtration by simple and efficient laser irradiation method.
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http://dx.doi.org/10.1016/j.jhazmat.2020.124395DOI Listing
April 2021

Surface Laser-Marking and Mechanical Properties of Acrylonitrile-Butadiene-Styrene Copolymer Composites with Organically Modified Montmorillonite.

ACS Omega 2020 Aug 21;5(30):19255-19267. Epub 2020 Jul 21.

Jiangsu Key Laboratory of Environmentally Friendly Polymeric Materials, School of Materials Science and Engineering, Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering, Changzhou University, Changzhou 213164, Jiangsu, P.R. China.

In this study, organically modified montmorillonite (OMMT) was prepared by modifying MMT with a cationic surfactant cetyltrimethylammonium bromide (CTAB). The obtained OMMT of different loading contents (1, 2, 4, 6, and 8 wt %) was melt-blended with poly(acrylonitrile--butadiene--styrene) (ABS) to prepare a series of ABS/OMMT composites, which were laser marked using a neodymium-doped yttrium aluminum garnet (Nd:YAG) laser beam of 1064 nm under different laser current processes. X-ray diffraction (XRD), color difference spectrometer, optical microscope, water contact angle tests, scanning electron microscope (SEM), and Raman spectroscopy were carried out to characterize the morphology, structure, and properties of the laser-patterned ABS composites. The effects of the addition of OMMT and the laser marking process on the mechanical properties of ABS/OMMT composites were investigated through mechanical property tests. The results show that the obtained ABS/OMMT composites have enhanced laser marking performance, compared to the ABS. When the OMMT content is 2 wt % and the laser current intensity is 9 A, the marking on ABS composites has the highest contrast (Δ = 36.38) and sharpness, and the quick response (QR) code fabricated can be scanned and identified with a mobile app. SEM and water contact angle tests showed that the holes, narrow cracks, and irregular protrusion are formed on the composite surface after laser marking, resulting in a more hydrophobic surface and an increased water contact angle. Raman spectroscopy and XRD indicate that OMMT can absorb the near-infrared laser energy, undergo photo thermal conversion, and cause the pyrolysis and carbonization of ABS to form black marking, and the crystal structure itself does not change significantly. When the 2 wt % of OMMT is loaded, the tensile strength, elongation at break, and impact strength of ABS/OMMT are increased by 15, 20, and 14%, respectively, compared to ABS. Compared with the unmarked ABS/OMMT, the defects including holes and cracks generated on the surface of the marked one lead to the decreased mechanical property. The desirable combination of high contrast laser marking performance and mechanical properties can be achieved at an OMMT loading content of 2 wt % and a laser current intensity of 9 A. This research work provides a simple, economical, and environmentally friendly method for laser marking of engineering materials such as ABS.
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http://dx.doi.org/10.1021/acsomega.0c02803DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7409255PMC
August 2020

Laser induced porous electrospun fibers for enhanced filtration of xylene gas.

J Hazard Mater 2020 11 21;399:122976. Epub 2020 May 21.

Jiangsu Key Laboratory of Environmentally Friendly Polymeric Materials, School of Materials Science and Engineering, Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering, Changzhou University, Changzhou, 213164, China. Electronic address:

With the development of industry, the harm caused by volatile organic compound (VOC) gases to the human body has received much attention. This study reveals as the first attempt to apply laser irradiation technique to the preparation of porous electrospun fibers with excellent low-concentration VOC gases adsorption properties. The laser-sensitive polycarbonate (PC) fibers prepared from electrospinning was treated in air by scanning with a neodymium-doped yttrium aluminum garnet (Nd: YAG) pulsed laser beam to achieve porous structure. During the laser irradiation process, a series of changes such as melting, thermal degradation, and carbonization of the polymer fibers can change the surface structure. The morphology of the porous structure is related to the degree of laser-induced carbonization, and the laser current is an important parameter for determining the degree of laser-induced carbonization of a particular polymer. The results indicate that porous carbon structures can be created on the surface of the fiber membrane by controlling the degree of laser-induced carbonization, and a highly xylene gas adsorption efficiency is exhibited. This study may provide useful insights for developing electrospun porous fibers with VOC adsorption by simple, effective and environmentally friendly laser post-processing process.
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http://dx.doi.org/10.1016/j.jhazmat.2020.122976DOI Listing
November 2020

Facile preparation of polyacrylamide/chitosan/FeO composite hydrogels for effective removal of methylene blue from aqueous solution.

Carbohydr Polym 2020 Apr 17;234:115882. Epub 2020 Jan 17.

Jiangsu Key Laboratory of Environmentally Friendly Polymeric Materials, School of Materials Science and Engineering, Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering, Changzhou University, Changzhou, 213164, Jiangsu, China; Ecology and Resources Engineering College, Wuyi University, Wuyishan, 354300, China. Electronic address:

In this study, FeO magnetic nanoparticles were synthesized in situ in the polyacrylamide/chitosan (PAAm/CS) hydrogel networks. The obtained hydrogels are characterized by Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), X-ray diffraction (XRD), and Raman spectroscopy. The results confirm that the three-dimensional network structure of the hydrogels is incorporated with FeO nanoparticles. The adsorption properties of PAAm/CS/FeO hydrogels for methylene blue (MB) in aqueous solution were studied using Ultraviolet and visible spectrophotometry (UV-vis). The results show that when compared to PAAm/CS hydrogels, PAAm/CS/FeO hydrogels can adsorb MB with higher adsorption capacities of approximately 1603 mg/g, and the kinetics and isotherm models of the adsorption process could be better described by the pseudo-first order model and Langmuir isotherm model, respectively. Due to the facile preparation, high adsorption capacity, and low cost, the PAAm/CS/FeO hydrogels are good adsorbents for MB and exhibit significant potential in the treatment of sewage.
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http://dx.doi.org/10.1016/j.carbpol.2020.115882DOI Listing
April 2020

Facile Fabrication of High-Contrast and Light-Colored Marking on Dark Thermoplastic Polyurethane Materials.

ACS Omega 2019 Dec 27;4(24):20787-20796. Epub 2019 Nov 27.

Jiangsu Key Laboratory of Environmentally Friendly Polymeric Materials, School of Materials Science and Engineering, Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering, Changzhou University, Changzhou 213164, Jiangsu, China.

In this work, using ferroferric oxide (FeO) and zirconium oxide (ZrO) as laser-sensitive particles and thermoplastic polyurethane (TPU) as the matrix resin, a series of TPU/FeO/ZrO composites were prepared by melt blending, and the effect of the laser marking additive content, composition, and laser marking parameters on the laser marking properties of composites was investigated. The laser marking mechanism of FeO/ZrO additives and the role of each component in TPU laser marking were studied by metallographic microscopy, color difference test, scanning electron microscopy, and Raman spectroscopy. FeO nanoparticles as a laser sensitizer component, on the one hand, can act as a pigment to make the TPU substrate black and, on the other hand, can absorb laser energy to contribute to the formation of laser markings on TPU composite surfaces. In addition, the introduction of ZrO nanoparticles can help absorb the laser energy, while the contrast can be improved to enhance the laser marking performance of the TPU composite. Through thermogravimetric analysis, the changes in the thermally stable properties of TPU composites before and after laser marking were investigated, and the results indicated that FeO/ZrO nanoparticles can absorb the laser energy, causing melting and pyrolysis of the TPU backbone at a high temperature, to produce a gaseous product resulting in foaming. Finally, the high-contrast and light-colored markings were formed on the black TPU composite surface. This work provides a facile method for producing high-contrast and light-colored markings on the dark TPU composite surface.
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http://dx.doi.org/10.1021/acsomega.9b03232DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6906935PMC
December 2019

Colorimetric film based on polyvinyl alcohol/okra mucilage polysaccharide incorporated with rose anthocyanins for shrimp freshness monitoring.

Carbohydr Polym 2020 Feb 13;229:115402. Epub 2019 Oct 13.

School of Food and Biological Engineering, Hefei University of Technology, 230009, Hefei, Anhui, PR China; Anhui Institute of Agro-Products Intensive Processing Technology, 230009, Hefei, Anhui, PR China.

In this work, a colorimetric film was designed for shrimp freshness monitoring by incorporating rose anthocyanins (RAs) in polyvinyl alcohol/okra mucilage polysaccharide (PVA/OMP) composite film. The presence of OMP changed the film-forming solution from Newtonian to non-Newtonian fluid. The addition of OMP and RAs decreased the crystalline of PVA due to the hydrogen bonds among RAs, OMP and PVA. An appropriate content of RAs and OMP could improve the film mechanical and barrier properties. The colorimetric film showed distinguishable color changes at pH 2-12 and was high sensitive to volatile ammonia. The target film of PVA/OMP-RAs could effectively monitor shrimp freshness in real time and the color changes were easily distinguished by naked eye, suggesting its potential in intelligent packaging for freshness monitoring of aquatic products and meat foods.
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http://dx.doi.org/10.1016/j.carbpol.2019.115402DOI Listing
February 2020

Antibacterial activity and cytotoxicity of novel silkworm-like [email protected] MoS.

Colloids Surf B Biointerfaces 2019 Nov 5;183:110491. Epub 2019 Sep 5.

School of Food and Biological Engineering, Hefei University of Technology, 230009, Hefei, Anhui, PR China; Anhui Institute of Agro-Products Intensive Processing Technology, 230009, Hefei, Anhui, PR China.

Recently, molybdenum disulfide functionalized with poly-ethylene glycol (PEGylated MoS) has been widely used as a new drug delivery vehicle in biomedical field. However, the weak antibacterial activity of PEGylated MoS limits its application as an antibacterial agent. In this work, a novel silkworm-like conjugate of nisin loaded PEGylated MoS ([email protected] MoS) was developed for antibacterial application. The morphology and structure of PEGylated MoS were strongly dependent on the Mo/S molar ratio of precursors during the solvothermal process. The silkworm-like skeleton was well kept after loading with nisin. A high level of reactive oxygen species (ROS) induced by the conjugate was an important cause of bacteria death. Due to the different structure of cell membranes, the sharp edges could more easily puncture into Escherichia coli (E. coli) as compared with Staphylococcus aureus (S. aureus) and produced more intracellular ROS, which improved the antibacterial activity of nisin against E. coli. As a result, [email protected] MoS displayed the antibacterial activity against both gram-positive and gram-negative bacteria. Furthermore, the toxicity of the conjugate was very low. Therefore, the target conjugate of [email protected] MoS may have great potential application as an antibacterial agent.
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http://dx.doi.org/10.1016/j.colsurfb.2019.110491DOI Listing
November 2019

Fabrication of Phosphate-Imprinted PNIPAM/SiO₂ Hybrid Particles and Their Phosphate Binding Property.

Polymers (Basel) 2019 Feb 2;11(2). Epub 2019 Feb 2.

Jiangsu Key Laboratory of Environmentally Friendly Polymeric Materials, School of Materials Science and Engineering, Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering, Changzhou University, Changzhou 213164, China.

A SiO₂ microsphere imprinted by phosphate ions was prepared with the use of phosphate ion as the template molecule and tetraethoxysilane as the precursor. Thereafter, the imprinted SiO₂ microspheres were modified with 3-(trimethoxysilyl)propyl methacrylate ([email protected]₂), followed by introducing the double bond. In the presence of [email protected]₂, using -isopropylacrylamide as monomer, and potassium persulfate as initiator, polymer/inorganic hybrid particles (PNIPAM/SiO₂) were prepared. Fourier transform infrared spectroscopy, thermogravimetric analysis, nitrogen adsorption-desorption test, and transmission electron microscope were employed for the characterization of molecular imprinted SiO₂ microspheres and PNIPAM/SiO₂ hybrid particles. The effects of phosphate concentration, pH value, and adsorption temperature on the phosphate binding properties of PNIPAM/SiO₂ hybrid particles were studied by UV-vis spectrophotometer. The experimental results shed light on the fact that the PNIPAM structure is beneficial for the improvement of the adsorption ability of phosphate-imprinted SiO₂ microspheres. With the increase in the initial phosphate concentration, the adsorption capacity of hybrid particles to phosphate ions increased to 274 mg/g at pH = 7 and 15 °C. The acid condition and the temperature below the low critical solution temperature (LCST) of PNIPAM are favorable to the adsorption of phosphate ions by PNIPAM/SiO₂ hybrid particles, and the maximum adsorption capacity can reach 287 mg/g (at pH = 5 and 15 °C). The phosphate imprinted polymer/inorganic hybrid material is expected to be put to use in the fields of phosphate ions adsorption, separation, and recovery.
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http://dx.doi.org/10.3390/polym11020253DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6419039PMC
February 2019

Preparation of near-infrared laser responsive hydrogels with enhanced laser marking performance.

Soft Matter 2019 Apr;15(14):2950-2959

Jiangsu Key Laboratory of Environmentally Friendly Polymeric Materials, School of Materials Science and Engineering, Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering, Changzhou University, Changzhou, Jiangsu 213164, China.

Polystyrene modified bismuth oxide particles ([email protected]) were prepared and characterized by Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). Using acrylamide (AM) as a monomer, and [email protected] as laser sensitive additives, PAM/[email protected] hydrogels were fabricated and treated by a 1064 nm near-infrared laser. The laser responsive properties of PAM/[email protected] hydrogels were investigated at different current intensities and loading content of [email protected] by visual observation, optical microscopy, and SEM, and the mechanism of laser response was analyzed by XRD and Raman spectroscopy. The results indicate that the PAM hydrogel with added [email protected] particles showed excellent response to the laser, and high contrast and resolution text and pattern marks on the hydrogel surface can be obtained. The selection of suitable laser current intensity is key to the laser response of the PAM/[email protected] composite hydrogel. Through analysis of XRD, Raman spectroscopy, and TGA data, the laser marking of the PAM/[email protected] hydrogels originates from the generation of both bismuth metal and amorphous carbonized materials. After adding [email protected] with a loading content from 1% to 3%, the mechanical properties of the hydrogels were improved, but the swelling properties were finally decreased.
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http://dx.doi.org/10.1039/c8sm02635aDOI Listing
April 2019

Nanolayer coextrusion: An efficient and environmentally friendly micro/nanofiber fabrication technique.

Mater Sci Eng C Mater Biol Appl 2019 Feb 7;95:292-301. Epub 2018 Nov 7.

Key Laboratory of Advanced Civil Engineering Materials, School of Materials Science & Engineering, Tongji University, Shanghai 201804, China. Electronic address:

Researchers have developed many types of nanoscale materials with different properties. Among them, nanofibers have recently attracted increasing interest and attention due to their functional versatility and potential applications in diverse industries, including tapes, filtration, energy generation, and biomedical technologies. Nanolayer coextrusion, a novel polymer melt fiber processing technology, has gradually received attention due to its environmental friendliness, efficiency, simplicity and ability to be mass-produced. Compared with conventional techniques, nanolayer coextruded non-woven nanofibrous mats offer advantages such as a tunable fiber diameter, high porosity, high surface area to volume ratio, and the potential to manufacture composite nanofibers with different components to achieve desired structures and properties. Dozens of thermoplastic polymers have been coextruded for various applications, and the variety of polymers has gradually continued to increase. This review presents an overview of the nanolayer coextrusion technique and its promising advantages and potential applications. We discuss nanolayer coextrusion theory and the parameters (polymer and processing) that significantly affect the fiber morphology and properties. We focus on varied applications of nanolayer coextruded fibers in different fields and conclude by describing the future potential of this novel technology.
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http://dx.doi.org/10.1016/j.msec.2018.11.011DOI Listing
February 2019

Antibacterial activity and cytotoxicity of l‑phenylalanine-oxidized starch-coordinated zinc (II).

Int J Biol Macromol 2019 Feb 12;123:133-139. Epub 2018 Nov 12.

School of Food Science and Engineering, Hefei University of Technology, 230009 Hefei, Anhui, PR China; Anhui Institute of Agro-Products Intensive Processing Technology, 230009 Hefei, Anhui, PR China.

Zn (II) coordination compounds have aroused growing attentions as antibacterial entities. In the present work, we fabricated a new antibacterial complex of l‑phenylalanine‑oxidized starch-coordinated zinc (II) (l‑Phe-OSt→Zn (II)) by successive reactions of oxidization, Maillard and coordination. Maillard reaction occurred between l‑Phe and OSt to form l‑Phe-OSt, which was then coordinated with Zn (II) by carboxyl groups for l‑Phe-OSt→Zn (II). The complex showed good antibacterial activity and the antibacterial activity against E. coli was slightly poorer than B. subtilis. The presence of complex favored the generation of reactive oxygen species (ROS) in bacteria and the ROS level in B. subtilis was higher than that in E. coli. Furthermore, the toxicity of l‑Phe-OSt→Zn (II) towards HT-29 cells was very low. The characteristics of better antibacterial activity and less cytotoxicity endow l‑Phe-OSt→Zn (II) a great potential of application as a food additive.
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http://dx.doi.org/10.1016/j.ijbiomac.2018.11.057DOI Listing
February 2019

Genomic analyses of primitive, wild and cultivated citrus provide insights into asexual reproduction.

Nat Genet 2017 May 10;49(5):765-772. Epub 2017 Apr 10.

Key Laboratory of Horticultural Plant Biology (Ministry of Education), Huazhong Agricultural University, Wuhan, P.R. China.

The emergence of apomixis-the transition from sexual to asexual reproduction-is a prominent feature of modern citrus. Here we de novo sequenced and comprehensively studied the genomes of four representative citrus species. Additionally, we sequenced 100 accessions of primitive, wild and cultivated citrus. Comparative population analysis suggested that genomic regions harboring energy- and reproduction-associated genes are probably under selection in cultivated citrus. We also narrowed the genetic locus responsible for citrus polyembryony, a form of apomixis, to an 80-kb region containing 11 candidate genes. One of these, CitRWP, is expressed at higher levels in ovules of polyembryonic cultivars. We found a miniature inverted-repeat transposable element insertion in the promoter region of CitRWP that cosegregated with polyembryony. This study provides new insights into citrus apomixis and constitutes a promising resource for the mining of agriculturally important genes.
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http://dx.doi.org/10.1038/ng.3839DOI Listing
May 2017

Kinetics and Antioxidant Capacity of Proanthocyanidins Encapsulated in Zein Electrospun Fibers by Cyclic Voltammetry.

J Agric Food Chem 2016 Apr 11;64(15):3083-90. Epub 2016 Apr 11.

Anhui Institute of Agro-Products Intensive Processing Technology , 230009 Hefei, Anhui, PR China.

The proanthocyanidins encapsulated in zein (zein-PA) fibers was via electrospinning technique. The kinetics and antioxidant capacity of PA from zein fibers was investigated by cyclic voltammetry. Circular dichroism was used to investigate the secondary structure change of zein and its influence on the shape of fibers. The addition of PA caused a significant increase in viscosity and made fibers wider. These hydrogen bonds between zein and PA molecules would favor the α-helix change and decrease the β-folds of zein in electrospinning solutions, leading to a round-shaped tendency of fibers and enhancing the thermal properties slightly. Zein-PA fibers showed high encapsulation efficiency close to 100%, and the encapsulated PA retained its antioxidant capacity in fibers. Zein-PA fibers showed a good controlled release toward PA, and the predominant release of PA from fibers was Fickian diffusion, which could be well described by first-order model and Hixson-Crowell model.
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http://dx.doi.org/10.1021/acs.jafc.6b00540DOI Listing
April 2016
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