JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE
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2021
·Vol. 102
·期 5
·1919-1926
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IF 3.639
Jiandong Shen,Qixing Jiang,Wei Zhang,Yanshun Xu,Wenshui Xia
BACKGROUND Texture softening is always a problem during chilling of grass carp fillets. To solve this problem and provide for better quality of flesh, understanding the mechanism of softening is necessary. Gelatinolytic proteinases are suspected to play an essential role in the disintegration of collagen in softening of fish flesh. In the present study, the types and contribution of gelatinolytic proteinases in chilled fillets were investigated. RESULTS Four active bands (G1, 250 kDa; G2, 68 kDa; G3, 66 kDa; G4, 29 kDa) of gelatinolytic proteinases were identified in grass carp fillets by gelatin zymography. The effect of inhibitors and metal ions revealed that G1 was possibly a serine proteinase, G2 and G3 were calcium-dependent metalloproteinases and G4 was a cysteine proteinase. The effect of the inhibitors phenylmethanesulfonyl fluoride (PMSF), l -3-carboxy- trans -2,3-epoxy-propionyl- l -leucine-4-guanidinobutylamide (E-64) and 1,10-phenanthroline (Phen) on chilled fillets revealed that gelatinolytic proteinase activities were significantly suppressed. Collagen solubility indicated that metalloproteinase and serine proteinase played critical roles in collagen breakdown during the first 3 days, and cysteine proteinase revealed its effect after 3 days. Meanwhile, during chilled storage for 11 days, the final values of shear force increased 19.68% and 24.33% in PMSF and E-64 treatments when compared to control fillets respectively, whereas the increase after Phen treatment was 49.89%. CONCLUSION Our study concluded that the disintegration of collagen in post-mortem softening of grass carp fillets was mainly mediated by metalloproteinase and to a lesser extent by serine proteinase and cysteine proteinase. © 2021 Society of Chemical Industry.
研究领域:
食品科学
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生物化学
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DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2020
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IF 7.1
Yujie Gao,Yu Chen,Miaomiao Li,Lizhen Jia,Lianbin Zhang,Jintao Zhu
Identification or detection of pathogenic microbes is one of the most important aspects to prevent and/or treat bacterial infection. In this study, we report a facile yet versatile strategy for preparation of gelatin-based photonic hydrogel sensors for visual detection of Pseudomonas aeruginosa ( P. aeruginosa ). The photonic hydrogels are generated by in-situ photopolymerization of acrylamide (AM), N , N ’-methylenebis-(acrylamide) (BIS), and gelatin methacrylate (GelMA) with the self-assembled one-dimensional (1D) chain-like structures of carbon-encapsulated Fe 3 O 4 nanoparticles (Fe 3 O 4 @C NPs). In the presence of P. aeruginosa , the hydrolysis of gelatin triggered by gelatinase reduces the crosslinking density of photonic hydrogel, expands the hydrogel in volume, increases the lattice spacing of the colloidal particles, and red-shifts the reflection spectra of the photonic hydrogel. The optical appearance variation of the photonic hydrogel, resulting from the reflection peak shift, can be observed by naked eyes. Besides, we show that the photonic hydrogels exhibit negligible appearance changes with the presence of Escherichia coli ( E. coli ), indicating their potential for distinguishing various bacteria by a simple structural color variation. This finding provides a proof-of-concept for a colorimetric sensor for visual detection of P. aeruginosa and demonstrates the great potential of the photonic hydrogels in visual detection of pathogens.
研究领域:
生物医学工程
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微生物学
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材料科学
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DOI
高影响因子
Journal of Ocean University of China
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2025
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IF 1.2
Xu Gang,Chen Yulei,Mei Haize,Yang Ruqing,Xiao Xuchen,Weng Ling,Cao Minjie
Matrix metalloproteinases (MMPs) play essential roles in the metabolism of collagens; however, information regarding MMPs in aquatic animals is limited. To elucidate the specific role of MMPs in shrimp muscle degradation, proteinases with gelatinolytic activity were identified in the hepatopancreas of Litopenaeus vannamei (Lv). The gelatinolytic activity was suppressed by metalloproteinase inhibitors EDTA and EGTA to some degree, suggesting the existence of metalloproteinases. Then the catalytic domain of LvMMP-2 (LvMMP-2c) was cloned and expressed heterologously in the Pichia pastoris expression system. rLvMMP-2c (recombinant LvMMP-2c) demonstrated optimal gelatinolytic activity at pH 8.0 and 50 °C, and its activity could be enhanced by Ca 2+ and Ba 2+ . Type I collagen and myofibrillar proteins from shrimp were effectively hydrolyzed by rLvMMP-2c not only at 37 °C, but also at 4 °C, indicating its involvement in the postmortem tenderization of shrimp muscle. Our present study provided new information to elucidate the role of metalloproteinase underlying shrimp meat softening during cold storage, and suggested new strategies to prevent shrimp quality decrement during cold storage.
研究领域:
海洋生物学
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蛋白质组学
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食品科学
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DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2025
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IF 8.5
Mengwei Li,Yanan Zhang,Bingjie Xu,Haotian Ren,Yujie Gao,Jindan Wu
Dressings are prone to adhering to new tissues, leading to secondary harm to the wound during dressing replacement. To address this issue, many strategies have been proposed to endow dressings with anti-adhesive functions. However, the introduction of exogenous agents or stimuli is always needed, and difficulty in achieving adaptive removal is also present. Herein, an endogenous gelatinase-responsive core-shell nanofiber membrane containing hydroxy-terminated polydimethylsiloxane (HTPDMS) was developed for anti-adhesion applications. The core-shell nanofiber membrane is created via coaxial electrospinning technique, where a mixture of gelatin and polycaprolactone (PCL) serves as shell layer and HTPDMS serves as core layer. In the presence of gelatinase, the gelatin component in shell layer is degraded, and many grooves are formed on the surface, which provide channels for the migration of HTPDMS with low surface energy, further forming a hydrophobic lubricating coating on the rough surface. This coating enhances the hydrophobicity of the membrane while significantly reducing its protein adsorption characteristics and adhesion to isolated tissues. Moreover, the current nanofiber membrane is highly cytocompatible with L929 mouse fibroblasts. This finding provides a proof-of-concept for an anti-adhesive nanofiber membrane for adaptive removal and demonstrates great potential for alleviating patient discomfort during dressing replacement and enhancing wound healing.
研究领域:
生物材料学
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组织工程学
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再生医学
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DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2023
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IF 8.2
Xiao-Ling Lei,Kai Cheng,Yong-Guo Hu,Yong Li,Xiao-Lin Hou,Fang Zhang,Lin-Fang Tan,Zi-Tao Zhong,Jian-Hao Wang,Jin-Xuan Fan,Yuan-Di Zhao
Abscess wound caused by bacterial infection is usually difficult to heal, thus greatly affect people's quality of life. In this study, a biodegradable drug-loaded microneedle patch (MN) is designed for targeted eradication of S. aureus infection and repair of abscess wound. Firstly, the bacterial responsive composite nanoparticle (Ce6@GNP-Van) with a size of about 182.6 nm is constructed by loading the photosensitizer Ce6 into gelatin nanoparticle (GNP) and coupling vancomycin (Van), which can specifically target S. aureus and effectively shield the phototoxicity of photosensitizer during delivery. When Ce6@GNP-Van is targeted and enriched in the infected regions, the gelatinase secreted by the bacteria can degrade GNP in situ and release Ce6 , which can kill the bacteria by generating ROS under laser irradiation. In vivo experiments show that the microneedle is basically degraded in 10 min after inserting into skin, and the abscess wound is completely healed within 13 d after applying Ce6@GNP-Van-loaded MN patch to the abscess wound of the bacterial infected mice with laser irradiation, which can simultaneously achieve the eradication of biofilm and subsequent wound healing cascade activation, showing excellent synergistic antibacterial effect. In conclusion, this work establishes a synergistic treatment strategy to facilitate the repair of chronic abscess wound.
研究领域:
医学
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生物材料学
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感染与免疫
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DOI
PubMed
高影响因子
CNS Neuroscience & Therapeutics
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2020
·Vol. 26
·期 12
·1288-1302
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IF 4.074
Meng Gao,Weitian Lu,Yue Shu,Zhengyu Yang,Shanquan Sun,Jin Xu,Shengwei Gan,Shujuan Zhu,Guoping Qiu,Fei Zhuo,Shiye Xu,Yiying Wang,Junhong Chen,Xuan Wu,Juan Huang
Background Specific highly polarized aquaporin-4 (AQP4) expression is reported to play a crucial role in blood-brain barrier (BBB) integrity and brain water transport balance. The upregulation of polymerase δ-interacting protein 2 (Poldip2) was involved in aggravating BBB disruption following ischemic stroke. This study aimed to investigate whether Poldip2-mediated BBB disruption and cerebral edema formation in mouse bacterial meningitis (BM) model occur via induction of AQP4 polarity loss. Methods and Results Mouse BM model was induced by injecting mice with group B hemolytic streptococci via posterior cistern. Recombinant human Poldip2 (rh-Poldip2) was administered intranasally at 1 hour after BM induction. Small interfering ribonucleic acid (siRNA) targeting Poldip2 was administered by intracerebroventricular (i.c.v) injection at 48 hours before BM induction. A specific inhibitor of matrix metalloproteinases (MMPs), UK383367, was administered intravenously at 0.5 hour before BM induction. Western blotting, immunofluorescence staining, quantitative real-time PCR, neurobehavioral test, brain water content test, Evans blue (EB) permeability assay, transmission electron microscopy (TEM), and gelatin zymography were carried out. The results showed that Poldip2 was upregulated and AQP4 polarity was lost in mouse BM model. Both Poldip2 siRNA and UK383367 improved neurobehavioral outcomes, alleviated brain edema, preserved the integrity of BBB, and relieved the loss of AQP4 polarity in BM model. Rh-Poldip2 upregulated the expression of MMPs and glial fibrillary acidic protein (GFAP) and downregulated the expression of β-dystroglycan (β-DG), zonula occludens-1 (ZO-1), occludin, and claudin-5; whereas Poldip2 siRNA downregulated the expression of MMPs and GFAP, and upregulated β-DG, ZO-1, occludin, and claudin-5. Similarly, UK383367 downregulated the expression of GFAP and upregulated the expression of β-DG, ZO-1, occludin, and claudin-5. Conclusion Poldip2 inhibition alleviated brain edema and preserved the integrity of BBB partially by relieving the loss of AQP4 polarity via MMPs/β-DG pathway.
研究领域:
神经科学
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药理学
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分子生物学
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传染病学
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DOI
PubMed
高影响因子
ACS Sustainable Chemistry & Engineering
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2021
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IF 8.198
Zheng Zhou,Xin Ju,Yuyang Zhou,Yinghui Mu,Liangzhi Li
Enzyme-loaded microgels (μ-Gelzymes) have gained increasing attention for their facile fabrication, versatile applicability, and fine controllability. Herein, a series of poly(N-isopropylacrylamide) (PNIPAM)-based μ-Gelzymes (P-C) with a tunable surface potential were prepared to improve the cellulase biocatalytic effect. The P-C showed better cellulose affinity than free cellulase, highly reducing its nonproductive binding onto lignin, while the Langmuir adsorption affinity indexes (K) of P-C for cellulose and lignin were 1.19 and 0.34 g/L, whereas those of free cellulase were 0.44 and 3.92 g/L, respectively. Moreover, the biomass synergistic pretreatment with 1-ethyl-3-methylimidazolium acetate ([EMIM]OAc) and choline acetate ([Ch]OAc) resulted in an almost equal ζ-potential on lignin, cellulose, and hemicellulose. Microcrystalline cellulose (MCC) and bagasse (BC) substrate conversions achieved by P-C were 19.8 and 12.1% higher than those with free cellulase under 3% [Ch]OAc + 7% [EMIM]OAc in situ saccharification. The P-C ζ-potential and biomass glucose production demonstrated that the more the electroneutrality on P-C, the higher the glucose generation, suggesting that biomass saccharification can be controlled by adjusting the surface charge on μ-Gelzymes.
研究领域:
生物技术
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化学工程
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材料科学
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生物化学
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产品关联
DOI
高影响因子
Small
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2024
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IF 13
Minghui Jin,Peipei Su,Xiaocheng Huang,Ruhao Zhang,He Xu,Zhenbo Wang,Cuicui Su,Jaroslav M. Katona,Yumin Ye
Wearable sweat sensor offers a promising means for noninvasive real-time health monitoring, but the efficient collection and accurate analysis of sweat remains challenging. One of the obstacles is to precisely modulate the surface wettability of the microfluidics to achieve efficient sweat collection. Here a facile initiated chemical vapor deposition (iCVD) method is presented to grow and pattern polymer nanocone arrays with distinct superwettability on polydimethylsiloxane microfluidics, which facilitate highly efficient sweat transportation and collection. The nanoarray is synthesized by manipulating monomer supersaturation during iCVD to induce controlled nucleation and preferential vertical growth of fluorinated polymer. Subsequent selective vapor deposition of a conformal hydrogel nanolayer results in superhydrophilic nanoarray floor and walls within the microchannel that provide a large capillary force and a superhydrophobic ceiling that drastically reduces flow friction, enabling rapid sweat transport along varied flow directions. A carbon/hydrogel/enzyme nanocomposite electrode is then fabricated by sequential deposition of highly porous carbon nanoparticles and hydrogel nanocoating to achieve sensitive and stable sweat detection. Further encapsulation of the assembled sweatsensing patch with superhydrophobic nanoarray imparts self-cleaning and water-proof capability. Finally, the sweat sensing patch demonstrates selective and sensitive glucose and lactate detection during the on-body test.
研究领域:
材料科学
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纳米技术
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生物传感器
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可穿戴技术
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健康监测
✓ 已验证
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）