Materials
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2018
·Vol. 11
·期 10
·1883
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IF 2.467
Chao Peng,Guangxue Chen
In this study, poly(vinyl alcohol) (PVA) composite films enhanced by α-chitin nanowhiskers (ChWs) were prepared through heat treatment. The obtained membranes were assessed by means of FTIR spectroscopy, X-ray diffraction, thermogravimetric analysis, regular light transmittance, mechanical tests, permeability and water absorption. The influence of the nano-component and heat treatment on the mechanical, thermal and water-resistant properties of the composite membrane were analyzed. From the results of the work, the produced films with excellent barrier properties and inexpensive raw processed materials have great prospects in packaging applications.Keywords:α-chitin nanowhiskers;heat treatment;thermal stability;barrier property;packaging application
研究领域:
材料科学
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食品科学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
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2021
·
IF 6.165
Yuhuan Deng,Bin Liang,Xingtang Liang,Songlin Fan,Yanjuan Zhang,Yanzhen Yin,Huayu Hu,Zuqiang Huang,Yuben Qin
Chitin is difficult to be dissolved due to its dense structure, high crystallinity, and acetyl groups. Amorphization is conducive to enhancing the solubility of chitin. In this study, an effective mechanical activation-metal salt (MAMS) technology was used to pretreat α-chitin to improve its solubility in NaOH/urea solution. The chlorides of Fe and Al showed better synergistic effect with MA, especially FeCl 3 . The crystallization index of MA-FeCl 3 -pretreated chitin (MAFCCT) decreased to 4%, attributing to that Fe 3+ and Cl - jointly disrupted the intra- and intermolecular-hydrogen bonds in chitin. In addition, during the dissolution of MAFCCT, Fe 3+ fixed on chitin could form Fe(OH) 3 colloid with OH – to induce NaOH enter the interior of chitin molecules. The solubility of MAFCCT in NaOH/urea solution at −16 °C for 8 h reached 97.1%. MAMS pretreatment is a practical technology to enhance the solubility of chitin by destroying its stable crystal structure.
研究领域:
生物化学
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材料科学
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产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2019
·
IF 4.784
Chao Peng,Junfei Xu,Guangxue Chen,Junfei Tian,Minghui He
A series of highly porous and biocompatible poly (vinyl alcohol) (PVA) hydrogels containing partially deacetylated α-chitin nanowhiskers (ChWs) were fabricated by the double-cross-link (DC) with glutaraldehyde (GA) and repeating freeze-thawing cycle. Then these hydrogels were used as carrier for bovine serum albumin (BSA), which served as the model drug. The nanowhiskers worked effectively to raise the mechanical property of the PVA/ChWs hydrogels. This property increased significantly from 1.55 to 26.59 MPa with the increase of the ratio of ChWs to PVA from 0% to 40%. Additionally, the morphological properties of the gel matrix were comprehensively investigated. The results showed that the novel ChWs/PVA hydrogels were facilely constructed from sequential chemical cross-linking and physical cross-linking with GA. The hydrogel with the ChWs to PVA weight ratios of 40% achieved the highest equilibrium swelling ratio, and could release more than 80% of the BSA from its gel matrix within 75 h.
研究领域:
生物材料学
·
药剂学
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产品关联
DOI
PubMed
高影响因子
CARBOHYDRATE POLYMERS
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2013
·
IF 3.479
Yun Lu,Qingfeng Sun,Xilin She,Yanzhi Xia,Yixing Liu,Jian Li,Dongjiang Yang
α-Chitin nanofibers were fabricated with dried shrimp shells via a simple high-intensity ultrasonic treatment under neutral conditions (60 KHz, 300 W, pH = 7). The diameter of the obtained chitin nanofibers could be controlled within 20–200 nm by simply adjusting the ultrasonication time. The pulsed ultrasound disassembled natural chitin into high-aspect-ratio nanofibers with a uniform width (19.4 nm after 30 min sonication). The EDS, FTIR, and XRD characterisation results verified that α-chitin crystalline structure and molecular structure were maintained after the chemical purification and ultrasonic treatments. Interestingly, ultrasonication can slightly increase the degree of crystallinity of chitin (from 60.1 to 65.8). Furthermore, highly transparent chitin films (the transmittance was 90.2% at a 600 nm) and flexible ultralight chitin foams were prepared from chitin nanofiber hydrogels.
研究领域:
材料科学
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生物学
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产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2025
·
IF 8.5
Yuan Yu,Kailiang Leng,Rong Cao,Min Yang,Junkui Miao,Xixi Wang,Xiaoyan Tang,Xiaofang Liu
Chitinase catalyzes the β-(1,4) glycosidic bonds in chitin, demonstrating antifungal and insecticidal properties. Some chitinases contain multiple chitin-binding domains (ChBDs), which enhance catalysis on α-chitin. However, the specific roles of each ChBD in chitinase function remain poorly understood. Herein, Chitiniphilus eburneus Ce 0303 and ChBD-truncated chitinases were expressed to investigate the contribution of its ChBDs to binding, stability, and catalytic properties. Conserved aromatic residues including Trp-5, Tyr-19, Trp-119 and Trp-132 within ChBDs are crucial for substrate binding. The interaction between substrate and ChBD1 is primarily mediated by hydrogen bonds, while ChBD2 relies predominantly on hydrophobic interactions. Truncated chitinase Chi-2 containing ChBD1 exhibited enhanced catalytic efficiency toward α-chitin, with specific activity of 2.62 U mg −1 and k cat /K m value of 1.16 mL mg −1 s −1 , whereas Ce 0303 and truncated Chi-1 containing ChBD2 demonstrated superior thermal stability, with half-lives of 3.36 and 3.22 h at 55 °C, respectively. ChBDs reduced the crystallinity of α-chitin to as low as 70.55 %, thus enhancing catalytic domain's accessibility, while the endo - and exo -catalytic activities of Ce 0303 remained unchanged. This study advances the understanding of ChBDs function, providing a theoretical foundation for improving α-chitin catalysis and expanding the applications of chitinase in agriculture and aquaculture.
研究领域:
微生物学
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酶学
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分子生物学
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蛋白质工程
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农业生物技术
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产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2025
·
IF 8.5
Alei Zhang,Runke Wang,Xi Zhou,Quanzhen Liu,Xin Zhang,Feifei Chen,Kequan Chen
In this work, a GH18 chitinase (Chi1) with highly hydrolytic activity was identified from Chitinibacter sp. GC72 and successfully cloned and expressed in Escherichia coli BL21(DE3). The recombinant Chi1 exhibited specific activities of 362.6 U/mg against colloidal chitin and 56.7 U/mg against raw α-chitin. Analysis of hydrolysis pattern showed that Chi1 is a multifunctional chitinase, which mainly exhibited processive exo-acting activity with some endo-acting and N -acetyl glucosaminidase activities. Structural analysis and molecular docking were conducted to explore the potential mechanism underlying the highly and multiple activities. Furthermore, Chi1 was utilized to convert raw α-chitin into reducing sugar affording 48.6% ( w / w ) yield of total sugar with a 1:4 molar ratio of NAG to NAG 2 , while also displaying hydrolysis activity to chitinous biomass with 4.1% sugar yield. This study provides a potent chitinase to hydrolyze chitinous resource with unusual product pattern, showing great potential for further industrial applications.
研究领域:
微生物学
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分子生物学
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生物技术
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酶学
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生物信息学
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环境生物技术
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工业生物技术
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结构生物学
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）