RESEARCH ON CHEMICAL INTERMEDIATES
·
2020
·Vol. 47
·期 2
·663-682
·
IF 2.262
Zhu Lin,Zheng Xingwen,Zeng Xianguang,Gong Min,Guo Lei
The inhibitive effect and inhibition mechanism of l -lysine derivatives, namely α- N -benzyloxycarbonyl- l -lysine (α-NL) and ε- N -benzyloxycarbonyl- l -lysine (ε-NL), on the corrosion of carbon steel in 0.5 M H 2 SO 4 solution were investigated by electrochemical technique, weightlessness test, scanning electron microscope, atomic force microscope, infrared attenuated reflectance spectroscopy and quantum chemical calculation. The results showed that α-NL and ε-NL as moderate cathodic inhibitors mainly inhibited the cathodic reaction of carbon steel in 0.5 M H 2 SO 4 solution, and the terminal substituted ε-NL showed better corrosion inhibition than the α- N -benzyloxycarbonyl protected α-NL. Their inhibition efficiencies increased with the increase in inhibitor concentration, and the inhibition efficiency of α-NL and ε-NL with concentration of 10 mmol can reach 53.4% and 61.5%, respectively, but decreased with rising temperature. The adsorption of investigated inhibitors on the surface of carbon steel obeyed the modified Langmuir isotherm and El-Awady thermodynamic-kinetic model, and the thermodynamic and kinetic parameters were determined to discuss the mechanism of inhibition of α-NL and ε-NL. Moreover, Quantum chemical calculation gave further insight into the inhibition mechanism of α-NL and ε-NL and was employed to reveal the reasons for their differences in inhibition performance.
研究领域:
材料科学
·
电化学
·
量子化学
✓ 已验证
DOI
高影响因子
Food and Bioprocess Technology
·
2023
·
IF 5.6
Lin Junxin,Sun Peizi,Zhao Yanfen,Du Xiaoping,Ren Xiang,Man Hao,Li Dongmei
Heat treatment reduces the quality of Antarctic krill ( Euphausia superba ) meat, thus greatly limiting its industrial application. It was found that L-Lys immersion pretreatment can effectively improve the quality of heat-treated Antarctic krill meat; the underlying mechanism is unclear. Therefore, this study aimed to investigate the effect of L-Lys concentrations (0, 25, 50, 100, and 200 mM) on the aggregation behavior and structure of Antarctic krill myofibrillar protein solution before and after heat treatment. Compared with the untreated group, L-Lys decreased the surface hydrophobicity and particle size of the heat-treated Antarctic krill protein by 2.38 times and 18.27 times while increasing the solubility by 3.59 times. Furthermore, L-Lys intervention inhibited the formation of disulfide bonds in myofibrillar protein of the heat-treated Antarctic krill, enhanced the intermolecular hydrogen bonding force, improved the orderliness of the secondary structure, and “exposed” the tyrosine residues of the protein molecule. As a result, the polarity of the microenvironment was enhanced while the tertiary structure of the protein was altered, thus inhibiting thermal aggregation. This study reveals the mechanism of L-Lys inhibition of thermal aggregation behavior of Antarctic krill myofibrillar protein. Our results provide insights into the development and utilization of Antarctic krill protein in the food industry.
研究领域:
食品科学
·
蛋白质化学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF FOOD SCIENCE AND TECHNOLOGY
·
2022
·Vol. 57
·期 4
·2556-2567
·
IF 3.612
Xiuyun Guo,Junjun Wu,Xiangren Meng,Yawei Zhang,Zengqi Peng
Summary This study investigated the effects of l -lysine (Lys) and l -histidine (His) on the oxidative characteristics and gel properties of porcine myofibrillar proteins (MP). Results showed that Lys and His had a strong ferrous ion-chelating ability and hydroxyl radical-scavenging activity. Moreover, Lys and His inhibited the protein carbonyl formation and MP aggregation at 0.2 M and 0.6 M NaCl, respectively, in a dose-dependent manner. Furthermore, 2 and 4 mg mL −1 Lys and His decreased the oxidation-induced loss of the tertiary structure of MP accompanied by the lower surface hydrophobicity. The water-holding capacity and gel strength of MP gels increased with increasing Lys and His concentrations due to more regular and lamellar structures with smaller and homogeneous pores at 0.6 M NaCl and more orderly crosslinking via fibrous filament at 0.2 M NaCl. In summary, Lys and His chelated the ferrous ions and scavenged hydroxyl radicals, decreased the oxidation-induced physicochemical changes, thus preventing oxidative damage during the formation of a three-dimensional gel network, which resulted in better gel quality.
研究领域:
食品科学
·
生物化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF BIOMEDICAL MATERIALS RESEARCH PART B-APPLIED BIOMATERIALS
·
2025
·Vol. 113
·期 1
·e35528
·
IF 3.4
Yifan Lu,Xiangxin Lou,Wenxin Wang,Ziting Yang,Haochen Yao,Jinglei Wu
Massive bleeding and bacterial infection of wounds may be life-threatening or even lead to death. Nowadays, gelatin-based hemostatic sponges have been widely used, but gelatin is not antibacterial and has poor structural stability. In this study, we mixed an antibacterial polypeptide, ε-poly-L-lysine (EPL), into gelatin. A gelatin/ε-poly-L-lysine (Gel/EPL) sponge with hemostatic and antibacterial functions was prepared by ultraviolet (UV) crosslinking lyophilized Gel/EPL composite. Scanning electron microscopy showed that the sponge had an interconnected porous structure. The incorporation of EPL increased the hydrophilicity and water absorption capacity of the Gel/EPL sponge. The sponge had better structural stability after UV crosslinking. The antibacterial assay showed that bacteria could not grow normally around the Gel/EPL sponge. The contact between blood components and the sponge initiated coagulation via exogenous pathway activation, and no hemolysis occurred. In addition, in vivo experiments confirmed that the sponge has a faster clotting time and lower blood loss. These findings show that the developed Gel/EPL sponge has great potential as a novel hemostatic agent that can quickly stop bleeding and fight bacterial infections.
研究领域:
生物材料学
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医学工程
·
药剂学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Molecular Catalysis
·
2021
·
IF 5.062
Mengzhe Li,Xiaohua Shen,Miaoqing Liu,Jianjun Lu
L-lysine is used as a crystallization regulator, and a two-step synthesis method is adopted in a concentrated gel system, which provides a new route to synthesize of nano-sized TS-1 zeolite. The new synthesis strategy was used to successfully synthesize TS-1 zeolite with a particle size less than 100 nm. The rate of crystal nucleation is faster than the crystal growth at the low temperature in the first step. Introduction of L-lysine can prevent crystal growth to form nano-sized TS-1 zeolite at the high temperature in the second step. Meanwhile, L-lysine decrease the pH value of the gel system, which is favorable for Ti atoms to incorporate the TS-1 framework. TS-1 nanozeolite can effectively reduce the diffusion resistance, and nanozeolite has a large specific surface area and high stability. Therefore, TS-1 nanozeolite exhibits the excellent catalytic performance during the hydroxylation of benzene. The conversion of benzene has been greatly improved and the types of by-products are effectively reduced. The conversion of benzene reached 50.2%, and the yield of phenol was 30.8% without by-product benzoquinone. TS-1 nano-zeolite as a catalyst for benzene hydroxylation shows great potential in industrial application.
研究领域:
化学工程
·
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
Foods
·
2024
·Vol. 13
·期 4
·629
·
IF 4.7
Yongkang Xie,De Chen,Jianxin Cao,Xuejiao Wang,Xiaoyu Yin
This study aimed to investigate the synergistic effects of high-intensity ultrasound (0, 5, 10, 15, and 20 min) in combination withL-lysine (15 mM) on improving the solubility and flavour adsorption capacity of myofibrillar proteins (MPs) in low-ion-strength media. The results revealed that the ultrasound treatment for 20 min or the addition ofL-lysine (15 mM) significantly improved protein solubility (p< 0.05), withL-lysine (15 mM) showing a more pronounced effect (p< 0.05). The combination of ultrasound treatment andL-lysine further increased solubility, and the MPs treated with ultrasound at 20 min exhibited the best dispersion stability in water, which corresponded to the lowest turbidity, highest absolute zeta potential value, and thermal stability (p< 0.05). Based on the reactive and total sulfhydryl contents, Fourier transform infrared spectroscopy, and fluorescence spectroscopy analysis, the ultrasound treatment combined withL-lysine (15 mM) promoted the unfolding and depolymerization of MPs, resulting in a larger exposure of SH groups on the surface, aromatic amino acids in a polar environment, and a transition of protein conformation from α-helix to β-turn. Moreover, the combined treatment also increased the hydrophobic bonding sites, hydrogen-bonding sites, and electrostatic effects, thereby enhancing the adsorption capacity of MPs to bind kenone compounds. The findings from this study provide a theoretical basis for the production and flavour improvement of low-salt MP beverages and the utilisation of meat protein.
研究领域:
食品科学
·
生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
TALANTA
·
2025
·
IF 6.1
Qiao Tong,Weijie Shen,Lu Zhang,Yu Cao,Xi Zou,Tingting Shi,Rang Xiao Zhuang,Shourong Liu,Jianjun Xi
A novel polymeric nanosensor (named PEINAC) based on polyethyleneimine (PEI), was designed for the selective fluorescence detection of l -lysine (L-Lys) in aqueous solutions. The sensor was synthesized through a one-step, three-component reaction involving orthophthalaldehyde (OPA), PEI, and acetylcysteine. This reaction simultaneously facilitated the creation of an isoindole fluorophore, which was chemically attached to the PEI backbone. The structural properties, size, and morphology of PEINAC were thoroughly analyzed using various characterization techniques. When introduced into a buffered solution at pH 7.0, PEINAC demonstrated high specificity for L-Lys, inducing a marked fluorescence enhancement at 450 nm upon excitation at 367 nm. The fluorescence intensity exhibited a linear relationship with L-Lys concentration, ranging from 1 μM to 1000 μM, with a detection limit of 0.13 μM. Notably, the sensor exhibited excellent selectivity, showing no significant interference from other biomolecules and common transition metal ions and anions. This sensor was successfully applied for L-Lys quantification in blood and urine samples and for cellular L-Lys imaging, demonstrating its potential in various analytical and biomedical applications.
研究领域:
分析化学
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2019
·Vol. 9
·期 35
·20044-20052
·
IF 3.049
Tianyu Liu,Dandan Chen,Feng Yang,Jinyao Chen,Ya Cao,Ming Xiang,Jian Kang,Ruizhang Xu
The application of a reverse osmosis (RO) membrane is greatly restricted on account of a trade-off between water flux and salt rejection, as well as poor anti-fouling properties. In order to improve the surface hydrophilicity of RO membranes, L-lysine (Lys) was grafted onto polyamide selective layers with the premise of maintaining the original surface morphology and thickness, which were verified through scanning electron microscopy and atomic force microscopy analysis. X-ray photoelectron spectroscopic measurements confirmed the occurrence of the reaction. After modification, the RO membranes exhibited notably enhanced hydrophilicity due to a steep decline in their water contact angles. The results of cross-flow filtration tests manifested that the modified membranes showed evident enhancements in water flux and salt rejection. For the optimized samples, the water flux increased by 22.45% compared with the pristine membrane, and the salt rejection rose up to 98.53% from the initial value of 95.44%. After grafting, the RO membranes performed much better in fouling resistance, especially towards protein and cationic foulants. The mechanism of how grafted Lys affected the performance of the RO membranes was analyzed. This research provides a feasible method to optimize the performance of RO membranes.
研究领域:
材料科学
·
环境工程
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2015
·
IF 3.391
Lingtian Wu,Yi Liu,Bo Chi,Zheng Xu,Xiaohai Feng,Sha Li,Hong Xu
Sucrose isomerase (SIase) is the key enzyme in the enzymatic synthesis of isomaltulose. Mesoporous titanium dioxide (M-TiO 2 ) and ε-poly- l -lysine-functionalized M-TiO 2 (EPL-M-TiO 2 ) were prepared as carriers for immobilizing SIase. SIase was effectively immobilized on EPL-M-TiO 2 (SI-EPL-M-TiO 2 ) with an enzyme activity of 39.41 U/g, and the enzymatic activity recovery rate up to 93.26%. The optimal pH and temperature of immobilized SIase were 6.0 and 30 °C, respectively. SI-EPL-M-TiO 2 was more stable in pH and thermal tests than SIase immobilized on M-TiO 2 and free SIase. K m of SI-EPL-M-TiO 2 was 204.92 mmol/L, and v max was 45.7 μmol/L/s. Batch catalysis reaction of sucrose by SI-EPL-M-TiO 2 was performed under the optimal conditions. The half-life period of SI-EPL-M-TiO 2 under continuous reaction was 114 h, and the conversion rate of sucrose after 16 batches consistently remained at around 95%, which indicates that SI-EPL-M-TiO 2 has good operational stability. Thus, SI-EPL-M-TiO 2 can be used as a biocatalyst in food industries.
研究领域:
食品科学
·
生物化学
·
酶工程
✓ 已验证
DOI
PubMed
高影响因子
LWT-FOOD SCIENCE AND TECHNOLOGY
·
2025
·
IF 6.6
Lingxia Su,Mengting Qiu,Qing jiang,Huiling Li,Wenjun Liu,Xumei Wang,Jun Liu,Zongcai Tu,Yanhong Shao
The aim was to evaluate the protective effects of 0.4% L-lysine (Lys) on the gel strength, water holding capacity and protein structure of frozen silver carp surimi, and to explore the mechanism of Lys delaying the quality deterioration of frozen silver carp surimi. Compared with control groups and commercial antifreeze agents, Lys-treated frozen surimi demonstrated superior rheological properties, gel strength, water holding capacity, and whiteness after 30 d of frozen storage while exhibiting a compact gel network. The mechanism of action was mainly due to the rise of pH value in the freezing process to form myofibrillar protein aggregates that exhibited high resistance to degradation, which prevented the exposure of hydrophobic amino acids and the oxidation of sulfhydryl groups, thus affecting the effective cross-linking of proteins during the gelation process and forming a denser fiber structure. The findings demonstrated the potential of Lys as a cryoprotectant, thereby establishing a theoretical foundation for the development of eco-friendly alternatives to antifreeze and high-gel frozen surimi products.
研究领域:
食品科学
·
生物化学
✓ 已验证
产品关联
DOI
高影响因子
TALANTA
·
2018
·
IF 4.244
Mingming Zhang,Juan Qiao,Shufeng Zhang,Li Qi
Herein, a unique protocol based on copper nanoclusters (CuNCs) probe for turn-on fluorescence sensing of L -lysine was developed. The fluorescent CuNCs with ovalbumin as the stabilizer was prepared by a simple, one-step and green method. When 370 nm was used as the excitation wavelength, the resultant CuNCs exhibited a pale blue fluorescence with the maximum emission at 440 nm. Interestingly, existence of L -lysine evoked the obvious fluorescence intensity increase of CuNCs. The detection limit of the proposed method for L -lysine was 5.5 μM, with a good linear range from 10.0 μM to 1.0 mM (r 2 = 0.999). Moreover, the possible mechanism for enhanced fluorescence intensity of CuNCs by addition of L -lysine was explored and discussed briefly. Further, the as-prepared fluorescent CuNCs was successfully applied in detection of L -lysine in urine. Our results demonstrated that L -lysine could be monitored by the probe, providing new path for construction of CuNCs as fluorescent probes and showing great potential in quantification of L -lysine in real samples.
研究领域:
分析化学
·
生物传感
·
医学检测
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIORESOURCE TECHNOLOGY
·
2021
·
IF 9.642
Cheng Wang,Xi Chen,Yingying Jiang,Na Li,Ping Zhu,Hong Xu
Facile and green fabrication of reduced graphene oxide on loofah sponge (rGOLS) carrier was applied for cell immobilization of ε-Poly- l -lysine (ε-PL) production. Due to surface properties including large specific surface area, high polarity, and low interaction energy, rGOLS-1 was employed as the optimum rGOLS to enhance immobilization of Streptomyces albulus . Compared with raw LS, batch experiments showed rGOLS-1 facilitated superior cell vitality for ε-PL production due to the presence of reduced graphene oxide. In the sequential fed-batch cultivation of Streptomyces albulus using rGOLS-1 with an aerobic plant fibrous-bed bioreactor (rGOLS-1-AFPB), the maximum ε-PL concentration and productivity reached to 39.2 ± 0.63 g/L and 0.48 g/L/h. The cells immobilized in rGOLS-1 with high vitality and ε-PL production efficiency were reused six times over a period of 624 h. This research afforded an effective approach to enhance the fermentation performance of immobilized cells with the design of an advanced immobilization carrier.
研究领域:
生物工程
·
微生物学
✓ 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）