Food Science and Human Wellness
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2024
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IF 5.6
Xiaokang Lu,Tianle Qi,Linjiang Guo,Lin Xiao,Hanbin Xu,Guobao Ning,Hui Zhao,Canpeng Li
Chymosin is one of the critical enzymes in cheese making. Herein, we proposed a novel fluorometric assay for chymosin determination. Firstly, covalent organic frameworks (COF) were synthesized and exfoliated to 2-dimensional COF nanosheets (COF NS) by ultrasound treatment. Gold nanoparticles (Au NPs) were loaded with COF NS to prepare AuNPs/COF NS (Au@COF NS). Secondly, rhodamine B (RhB) modified substrate peptide (Pep) for chymosin was linked with Au@COF NS to construct a Pep-Au@COF NS nanocomposite. For the sensing principle, fluorescence of RhB was quenched by Au@COF NS and the fluorescence intensity was weak due to the fluorescence resonance energy transfer between COF NS and RhB of Pep. However, in the presence of chymosin, the RhB was released by specific cleavage of the substrate peptide by chymosin and resulted in the recovery of fluorescence. The increased fluorescence intensity was proportional to the increase of chymosin concentration and thus a “turn on” fluorescent sensor for chymosin was constructed. The sensor showed a linear range in the concentration of 0.05 60.00 μg/mL for the detection of chymosin with a detection limit of 20 ng/mL. The sensor was used to quantify chymosin in rennet product with good selectivity, which has the potential applications in cheese manufacturing.
研究领域:
生物化学
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食品科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF DAIRY SCIENCE
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2021
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IF 4.034
Can-Peng Li,Feng Liu,Jing Zheng,Hui Zhao
ABSTRACT Chymosin is a predominant enzyme in rennet and is used in cheese production because of its excellent milk-clotting activity. Herein, we proposed a facile and label-free electrochemical method for determining chymosin activity based on a peptide-based enzyme substrate. The synthesized substrate peptide for chymosin was assembled onto the surface of the Au-deposited grassy carbon electrode. The current was proportional to chymosin activity, and thus chymosin activity could be determined. The detection ranges of chymosin activity were 2.5 to 25 U mL −1 . The detection limit of chymosin activity was 0.8 U mL −1 . The sensing platform was used to quantify chymosin activity in commercial rennet with high selectivity, excellent stability, and satisfactory reproducibility. We developed a facile, fast, and effective electrochemical assay for detecting chymosin activity, which has potential applications in cheesemaking.
研究领域:
食品科学
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生物化学
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分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2025
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IF 9.8
Ling Zhang,Feng Xiao,Sijie Hu,Anqi Bi,Ming Du,Xianbing Xu
Poor freeze-thaw stability seriously limits the application of Pickering emulsions in the frozen food industry. This study developed sodium caseinate-stabilized high internal phase emulsions (NaCas-HIPEs) with enhanced freeze-thaw stability through rennet modification. The freeze-thaw stability and 3D printing properties of NaCas-HIPEs significantly improved as rennet addition increased from 0 % to 0.5 ( w / v ). NaCas-HIPEs with 0.5 % rennet even maintained a stable oil-in-water emulsion structure after five freeze-thaw cycles. Changes in enthalpy and freezing/thawing point demonstrated that rennet modification improved freeze-thaw stability by reducing the ice crystal formation. Additionally, increasing rennet concentration significantly enhanced the apparent viscosity and viscoelasticity of NaCas-HIPEs, restricting ice crystal growth and preventing droplet aggregation during freezing and thawing. This improvement is attributed to the strong gel networks formed by rennet-induced casein between droplets, as shown by the cryo-SEM microscopy and SDS-PAGE analysis. This study This study presents an effective method for producing freeze-thaw stable emulsions, offering promising applications in the rapidly growing ready-to-eat food industry.
研究领域:
食品科学
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生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
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2024
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IF 8.3
Chenglong Fei,Lei Liu,Hedong Qi,Yuyang Peng,Jingfen Han,Chunru Wang,Xue Li
Autoimmune hepatitis (AIH) is a severe immune-mediated inflammatory liver disease whose standard of care is immunosuppressive treatment with inevitable undesired outcomes. Macrophage is acknowledged to aggravate liver damage, providing a promising AIH therapeutic target. Accordingly, in this study, a kind of curdlan-decorated fullerene nanoparticle (Cur-F) is fabricated to alleviate immune-mediated hepatic injury for treating AIH via reducing macrophage infiltration in a concanavalin A (Con A)-induced AIH mouse model. After intravenous administration, Cur-F primarily distributes in liver tissues, efficiently eliminates the excessive reactive oxygen species, significantly attenuates oxidative stress, and subsequently suppresses the nuclear factor kappa-B-gene binding (NF-κB) signal pathway, resulting in the lowered production of pro-inflammatory cytokines and the balancing of the immune homeostasis with the prevention of macrophage infiltration in the liver. The regulation of hepatic inflammation contributes to inhibiting inflammatory cytokines-induced hepatocyte apoptosis, decreasing the serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) contents and thus ameliorating immune-mediated hepatic injury. Notably, there is no detectable toxicity to the body. Our findings may open up novel avenues for AIH based on curdlan and fullerene materials.
研究领域:
药理学
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免疫学
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纳米技术
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肝病学
✓ 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）