JOURNAL OF PHARMACEUTICAL AND BIOMEDICAL ANALYSIS
·
2019
·
IF 2.983
Wei Gao,Xiao-lan Liu,Jia-yuan Li,Hong-zhen Lian,Li Mao
A porous zwitterionic monolithic column was prepared to rapidly and efficiently separate lysozyme from egg white. The monolith was synthesized in a stainless steel HPLC column (5 cm × 4.6 mm i.d.) by in-situ thermal initiated co-polymerization of N,N- dimethyl -N- methacryloxyethyl- N -(3-sulfopropyl) ammonium betaine (MSA) and ethylene dimethacrylate (EDMA). Due to the combination of quaternary ammonium and sulfonic groups on the monolithic matrix in one-pot process, the hydrophobic carbon chain and hydrophilic radical were obtained, which provided multiple driving forces for neutral, basic and acidic analytes, thus mix-mode chromatography mechanism contributed to the retention of different charged proteins. Properties such as composition, morphology and stability of the MSA-co-EDMA monolithic column were characterized by various analytical methods and the results showed that the monolith has large through-pores, good hydrophilicity and permeability. The effects of mobile phase pH and ionic strength on proteins were investigated, drawing the conclusion that the main adsorption and elution mechanism of lysozyme on MSA-co-EDMA monolith was electrostatic interaction, while those of other proteins included hydrophobic, hydrophilic and electrostatic interactions. Therefore, efficient separation of lysozyme and other proteins could be successfully achieved by switching the pH of mobile phase. Lysozyme can be adsorbed using 20 mmol/L phosphate buffer (pH 7.0) and eluted with 20 mmol/L phosphate buffer (pH 2.0). To prove the practicality of the monolithic column, it was also applied in the separation of lysozyme in egg white, which means the work has the potential for further development in proteome analysis of real biological samples.
研究领域:
生物化学
·
蛋白质组学
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2016
·
IF 4.758
Yan Zhang,Jingjing Jiang,Min Li,Pengfei Gao,Lihong Shi,Guomei Zhang,Chuan Dong,Shaomin Shuang
In this paper, we developed a simple one-pot method, employing inexpensive chicken egg white (EW) as a reducing/capping reagent, for microwave-assisted synthesis of water-soluble and well-dispersed chicken egg white-protected gold nanoclusters (EW@AuNCs) with far-red/near-infrared (FR/NIR) emission. The resultant AuNCs showed strong emission at 667 nm with a quantum yield of 7.23%. The excellent photostability, large Stokes shift (>350 nm), microsecond-scale lifetime and strong emission endowed EW@AuNCs potential as a sensing probe. The photoluminescence of EW@AuNCs could be quenched upon addition of either Hg 2+ or Cu 2+ ion. After ethylenediamine (En) was used as a masking agent, the EW@AuNCs offered highly selective for determination of Hg 2+ ion. Also, the resultant EW@AuNCs probe exhibited ultra-high sensitivity toward Hg 2+ ion with a detection limit as low as 20 pM, which is 500 times lower than the limit value (10 nM) defined by the U.S. Environmental Protection Agency in drinkable water. The proposed AuNCs probe for Hg 2+ ion has a linear range of 0.0446–5.90 nM and good repeatable response to 2.0 nM Hg 2+ with a relative standard deviation of 2.8% ( n = 5). Additionally, the applicability of the sensing system was also verified by analysis of Hg 2+ ion in tap water and pond water samples.
研究领域:
分析化学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
MOLECULES
·
2022
·Vol. 28
·期 1
·95
·
IF 4.927
Sheng-Wei Wang,Tian-Yi Wang
Lysozyme is a natural protein with a good bacteriostatic effect, but its poor inhibition of Gram-negative bacteria limits its development potential as a natural preservative. Therefore, the modification of natural lysozyme to expand the antimicrobial spectrum become the focus of lysozyme study. Egg white lysozyme has low cost, rich content in nature, is easy to obtain, strong stability, and high enzyme activity, so it can be applied in the modification of lysozyme. Egg white lysozyme was modified by chemical methods using organic acids. Caffeic acid and p-coumaric acid in organic acids were used as modifiers, and 1-Ethyl-3- (3-dimethylaminopropyl) carbodiimide hydrochloride and N-hydroxy succinimide were used as dehydration condensation agents during modification. A certain degree of modified lysozyme was obtained through appropriate modification conditions. The antibacterial properties and structure of the obtained two organic acid-modified lysozymes were compared with natural enzymes. The results showed that compared with the native enzyme, the activity of modified lysozyme decreased, but the inhibitory effect on Gram-negative bacteria was enhanced. The minimum inhibitory concentrations of caffeic acid-modified enzyme and p-coumaric acid-modified enzyme onEscherichia coliandPseudomonas aeruginosawere 0.5 mg/mL and 0.75 mg/mL, respectively. However, the antibacterial ability of modified lysozyme to Gram-positive bacteria was lower than that of the natural enzyme. The minimum inhibitory concentration of caffeic acid-modified enzyme and p-coumaric acid-modified enzyme toStaphylococcus aureusandBacillus subtiliswas 1.25 mg/mL. The peak fitting results of the amide-I band absorption peak in the infrared spectroscopy showed that the content of the secondary structure of the two modified enzymes obtained after modification was different from that of natural enzymes. In the study, two organic acids were used to modify egg white lysozyme, which enhanced the enzyme’s inhibition of Gram-negative bacteria, and analyzed the mechanisms for the change in the enzyme’s antibacterial ability from the perspective of the structural change of the modified enzyme, providing a new idea for lysozyme modification.Keywords:hen egg white lysozyme;chemical modification;antibacterial activity;secondary structure
研究领域:
生物化学
·
微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Xianmin Qin,Xue Cai,Yilin Wang,Linqin Chen,Jingjing Zhao,Yifan Zhang,Shenghui Bi,Ying Zhou,Qiujin Zhu,Yuxin Cheng,Yuanyuan Liu
Edible films are effective alternatives to plastic packaging, however, the hydrophilicity of edible films based on protein and polysaccharide limits the application. Therefore, we fabricated a water-stable hybrid film with a linear-spherical interpenetrating molecular topology network using egg white (EW), chitosan (CS), and pectin. Meanwhile, the nisin-tannin acid self-assembly complex nanoparticles were employed as a multifunctional cross-linker, antibacterial and antioxidant agent to improve the performance of films. The FTIR, XRD, and SEM analysis revealed that the conformation and crystalline structure rearrangement of chitosan induced by the alkaline environment provided by egg white enhanced the network structure of films, effectively avoided the addition of modifying reagents. The proposed hybrid films exhibited excellent properties, with EW/TNPCS3 showing the best overall performance. The water contact angle (WCA) increased to 105.27 ± 1.62°, and its dissolution and swelling rates were significantly lower than pure egg white and pure chitosan films. Moreover, tannin-nisin (TN) nanoparticles endowed the films with excellent antimicrobial activity against the common Gram-positive ( Staphylococcus aureus ) and Gram-negative ( Escherichia coli ) bacteria. Thus, the prepared blending films have great application potential in food preservation, especially to maintain stable performance in high humidity environment.
研究领域:
食品科学
·
材料科学
✓ 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）