NEW JOURNAL OF CHEMISTRY
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2017
·Vol. 41
·期 23
·14486-14497
·
IF 3.269
Yuxian Wang,Ling Jiang,Ce Wei,Hongman Zhang
Fatty acids, composed of an amphiphilic carbon chain and a carboxyl group, are a simple class of anion surfactants when they are protonated in the presence of an alkali. They can form ion-pairing amphiphile molecules and self-assemble into different nanostructures, which can be widely applied. However, the phase transition of these nanostructures can be easily triggered by external conditions, such as pH, temperature, the addition of salts and so on. In this work, medium-chain fatty acids (MCFAs) containing 8–12 carbons were chosen as the objects for self-assembly with organic amino counter-ions, L-arginine. We investigated the effects of chain length, pH, temperature and solvent on the phase transition based on diagrams, which could be determined by freeze fracture transmission electron microscopy (FF-TEM) and polarizing microscopy observations (PMO) combined with rheological properties. The results showed that rich phase behavior was observed in the octanoic acid (C8:0) system. However, it was insensitive to changes in pH because of the lower hydrophobicity. In contrast, for decanoic acid (C10:0) and lauric acid (C12:0) systems, phase transition from the L1 phase (micelles) to the Lα phase (vesicles) was observed and they showed stimulus-response to the change of pH. At the same time, lauric acid was sensitive to temperature, which was ascribed to the higher Krafft point. Besides, when the solvent was replaced by glycerin, phase transitions occurred from vesicles to micelles in these three systems. We hope that this phase transition observed in the MCFA system will provide a good insight into drug delivery, material science, and other related areas.
研究领域:
材料科学
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生物学
·
药物递送
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产品关联
DOI
高影响因子
Catalysts
·
2020
·Vol. 10
·期 9
·947
·
IF 3.52
Hongjie Hui,Yajun Bai,Tai-Ping Fan,Xiaohui Zheng,Yujie Cai
Putrescine, a biogenic amine, is a highly valued compound in medicine, industry, and agriculture. In this study, we report a whole-cell biocatalytic method inEscherichia colifor the production of putrescine, using L-arginine as the substrate. L-arginine decarboxylase and agmatine ureohydrolase were co-expressed to produce putrescine from L-arginine. Ten plasmids with different copy numbers and ordering of genes were constructed to balance the expression of the two enzymes, and the best strain was pACYCDuet-speB-speA. The optimal concentration of L-arginine was determined to be 20 mM for this strain. The optimum pH of the biotransformation was 9.5, and the optimum temperature was 45 °C; under these conditions, the yield of putrescine was 98%. This whole-cell biocatalytic method appeared to have great potential for the production of putrescine.Keywords:L-arginine;putrescine;Escherichia coli;whole-cell catalysis;co-expression
研究领域:
生物技术
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生物化学
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微生物学
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DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2024
·
IF 4.9
Xuanqi Hao,Xiao Zhang,Jianrong Wang,Chenchen Liu,Chuanhao Li,Ping Yang
To create fluorescent sensors for Cr (VI) and l-arginine detection, blue-emitting carbon dots (CDs, named as M-CDs) were prepared via a solvothermal synthesis by using m-phenylenediamine. The introduction of sulfuric acid changed the blue-emitting of CDs into green-emitting (named as S-CDs), in which the photoluminescence (PL) peak wavelengths of samples M-CDs and S-CDs were 450 and 540 nm, while their PL efficiencies were 21.7 and 84.2 % respectively. Sulfuric acid resulted in the average fluorescent lifetime of the CDs was prolonged into 8.19 from 4.65 ns. The photo and thermal stable tests demonstrated that theses CDs revealed excellent stability. Meanwhile, CDs flexible films with bright blue- and green-emitting were prepared utilizing the favorable solubility of CDs in polar solvents. Mono-dispersed CDs as luminescent materials demonstrated it promising prospects in luminescent devices field. Furthermore, M-CDs exhibited excellent selectivity towards Cr(VI) and l-arginine. The detected limit (0.86 μM for Cr(VI) and 0.43 μM for l-arginine) was determined by assessing the response of M-CDs to various concentrations of Cr(VI) ion and l-arginine solutions. These bright CDs revealed great potential for accurate detection of Cr(VI) and l-arginine.
研究领域:
材料科学
·
分析化学
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产品关联
DOI
高影响因子
Marine Drugs
·
2022
·Vol. 20
·期 11
·688
·
IF 6.085
Jingmin Cui,Yan Sun,Linqing Wang,Qin Miao,Wenqiang Tan,Zhanyong Guo
We successfully prepared a series ofl-arginine Schiff bases acylated chitosan derivatives, aiming to improve the antioxidant activity and antimicrobial activity of chitosan by introducing a furan ring, pyridine ring, andl-arginine structure. The accuracy of the structures of ten compounds was characterized by FT-IR and1H NMR. In terms of DPPH radical scavenging activity, except for compound CR3PCA, the scavenging rate of other compounds was higher than chitosan, especially CRCF and CRBF had strong scavenging abilities. At the same time, in the superoxide-radical scavenging activity assay, CRCF, CRBF, CR3PCA, CR2C3PCA, and CR2B3PCA were comparable to positive control at 1.60 mg/mL. Simultaneously, CRFF, CRCF, and CRBF had a certain inhibitory effect onBotrytis cinerea. Furthermore, the inhibitory effect of CRFF, CRCF, and CR3PCA onStaphylococcus aureuswas very well, close to the positive control at 1.00 mg/mL. CRCF and CR2B3PCA showed better inhibitory effects onEscherichia colithan other compounds. The MTT assay was used to determine the cytotoxicity of the chitosan derivatives, which proved their safety to fibroblast cells. In summary, the study indicated that some of these compounds have the potential for further development and utilization in the preparation of antioxidants and antimicrobial agents.Keywords:chitosan;l-arginine Schiff bases;heterocyclic compounds
研究领域:
生物化学
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食品科学
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药学
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产品关联
DOI
PubMed
高影响因子
EUROPEAN POLYMER JOURNAL
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2023
·
IF 6
Xin He,Jie Guan,Zhengpeng Chen,Zhengshuai Cao,Yunfan Li,Ziqiang Lei,Denglong Chen
In this study, bio-based L-arginine (Arg) and phosphite were selected as raw materials and used to modify magnesium hydroxide, generating an intermediate (APM) that was reacted with melamine (MEL) to produce a curing agent (APM-MEL) with flame retardant properties. A flame retardant epoxy resin (EP) was prepared in a curing reaction by adding APM-MEL and ammonium polyphosphate (APP) to the epoxy prepolymer in varying amounts (wt%). The chemical structure and surface morphology of APM-MEL have been characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS). The thermal stability, flame retardancy and mechanical properties were evaluated by thermogravimetric analysis (TG), the UL-94 vertical combustion test, use of the limiting oxygen index (LOI), cone calorimetry and bending tests. The results have revealed that the epoxy resin prepared from the addition of 5% APM-MEL and 15% APP achieved a UL-94 V-0 level with a LOI of 30.8%. Compared with pure EP, the peak heat release rate, total heat release, smoke production rate and total smoke production of the samples were reduced by 85.68%, 53.15%, 85.86% and 62.05%, respectively. The flexural strength and flexural modulus were improved by 117.3% and 130.5%, respectively. The bio-based functionalized magnesium hydroxide curing agent prepared in this study exhibits excellent flame retardant and mechanical properties, effectively reducing fire risk and can serve as the basis for the development of multifunctional curing agents.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
Materials Today Communications
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2024
·
IF 3.7
Shuo Yang,Nan Wang,Xiao–kun Ouyang,Yiwei Wu,Junhua Hu
Infection and inflammation are key factors affecting wound healing. Hydrogels are excellent wound dressings that provide a moist healing environment and serve as carriers for drugs or functional components. This work proposes a composite hydrogel, APLCE, composed of methyl methacrylate L-arginine (M-L-Arg) as an NO donor, synthesized through free radical polymerization with acrylamide (AM) and polyethylene glycol (PEG). The hydrogel matrix exhibits good water retention and mechanical properties. CaO 2 and ε-poly-L-arginine (EPL) are embedded in the hydrogel to form APLCE, where the hydrolysis of CaO 2 releases H 2 O 2 , triggering the release of arginine to release NO, inhibiting wound inflammation and bacterial growth. EPL added to the hydrogel synergistically with NO exhibits an antibacterial effect, with a bacterial inhibition rate exceeding 99 %. Animal experiments show that APLCE can completely eradicate bacteria in infected wounds, promote new skin formation, and achieve a wound closure rate of 94 % within 14 days. These findings emphasize the potential clinical application of APLCE as an innovative wound dressing material.
研究领域:
材料科学
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生物医学工程
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药学
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伤口愈合
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产品关联
DOI
高影响因子
Microorganisms
·
2024
·Vol. 12
·期 2
·360
·
IF 4.1
Shengwang Li,Youwei Yu,Peng Xie,Xianran Zhu,Chao Yang,Linjing Wang,Shaoying Zhang
Gray mold caused byBotrytis cinereais a common postharvest fungal disease in fruit and vegetables. The prevention and treatment of postharvest gray mold has been one of the hot research issues addressed by researchers. This study aimed to investigate the effect of L-methionine and L-arginine onBotrytis cinereain vitro and on cherry tomato fruit. The results of the in vitro experiment showed that L-methionine and L-arginine had significant inhibitory effects on the mycelial growth and spore germination ofBotrytis cinerea, and the inhibitory effects were enhanced with increasing L-methionine or L-arginine concentration. In addition, L-methionine and L-arginine treatment increased the leakage ofBotrytis cinereaelectrolytes, proteins and nucleic acids. The experiment involving propidium iodide staining and malondialdehyde content assay also confirmed that L-methionine and L-arginine treatment could lead to cell membrane rupture and lipid peroxidation. The results of scanning electron microscopy further verified that the morphology of hyphae was damaged, deformed, dented and wrinkled after treatment with L-methionine or L-arginine. Fruit inoculation experiments displayed that L-methionine and L-arginine treatments significantly inhibited the occurrence and development of gray mold in postharvest cherry tomato. Therefore, treatment with L-methionine or L-arginine might be an effective means to control postharvest gray mold in fruit and vegetables.
研究领域:
植物病理学
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食品科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2015
·
IF 4.097
Yi He,Xianhui Zhang
We report a facile, selective, and sensitive colorimetric assay for Mn 2+ ions based on the anti-aggregation of unmodified silver nanoparticles (AgNPs). In the absence of Mn 2+ ions, the addition of l -arginine to the AgNPs dispersion caused the aggregation of AgNPs via Ag–N covalent interaction, and the color of the solution changed from yellow to colorless. While the presence of Mn 2+ ions can prevent the aggregation of AgNPs due to the formation of the complex between Mn 2+ ions and l -arginine, accompanying with a distinct color change from colorless to yellow with the increase of Mn 2+ ions. Under the optimal experimental conditions, the absorbance at 390 nm was linearly proportional to the Mn 2+ ions concentration in the ranges from 0 to 700 nM, and from 5 μM to 70 μM, with a detection limit of 20 nM. Also, it was successfully used for the detection of Mn 2+ ions in environmental water samples.
研究领域:
分析化学
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环境科学
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纳米技术
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产品关联
DOI
高影响因子
FOOD CHEMISTRY
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2019
·
IF 5.399
Ruichang Gao,Tong Shi,Quancai Sun,Xiuting Li,David Julian McClements,Li Yuan
This research focused on the effects of l -arginine ( l -Arg) and l -histidine ( l -His) on the heat-induced aggregation of fish myosin. l -Arg/ l -His increased the pH of the myosin solution from 6.82 to 8.74 and 7.24, respectively, and decreased the turbidity, aggregate size, shear modulus, and breaking force. The incorporation of l -Arg/ l -His decreased the surface hydrophobicity during setting, but increased it during the two-step heating. The heat-induced aggregation of myosin was suppressed by both amino acids, with the inhibitory effect being greater for l -Arg than l -His. On one hand, the change in the pH played a critical role in suppressing the heat-induced aggregation of myosin. On the other hand, the characteristics of l -Arg/ l -His themselves, such as net charges and particular R-groups, were another main contributor to aggregation suppression. Particularly, l -Arg/ l -His could interact with exposed aromatic residues of myosin, and the interactions may dominate and overwhelm the burial of aromatic residues during two-step heating.
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
FOOD CHEMISTRY
·
2025
·
IF 9.8
Yuanxiu Liu,Tong Shi,Xiyue Cao,Xin Wang,Mengzhe Li,Chenya Lu,Xiaoli Zhang,Ying Tian,Li Yuan,Wengang Jin,Ruichang Gao
This study explored the influences of L-Arg in the ion migration and the quality of low-salt fish balls (L, 0.3 % NaCl). L-Arg significantly increased the weight gain and expansion rate of L by 18.33 % and 13.47 %. Water-holding capacity decreased from the internal to the external part of fish balls, consistent with the looser microstructure. Inductively coupled plasma-mass spectrometry (ICP-MS) revealed that L-Arg promoted Na + migration at setting ( P < 0.05), decreased the internal concentration from 34.38 to 30.37 mg/L and increased the external one from 25.78 to 29.80 mg/L ( P < 0.05). Conversely, Cl − concentration was decreased at setting and improved after the two-stage heating ( P < 0.05), indicating the suppressed Cl − migration. The partial replacement of Na + by L-Arg facilitated the protein unfolding, formation of disulfide bonds and exposure of tryptophan residues. This study enriched the mechanisms of salt reduction and quality maintenance for surimi products regarding ion migration.
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
ACS Applied Bio Materials
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2019
·
IF 0
Jingyuan Ma,Peizhi Yu,Boru Xia,Yuxiu An,Zhiqiao Wang
We synthesized a biodegradable and environmentally friendly shale inhibitor based on chitosan-grafted l-arginine (CA) for wellbore stability in shale formation. The structure of CA was characterized by Fourier-transform infrared spectroscopy. Linear swelling, shale hot-rolling recovery, shale inhibition durability, and sedimentation experiments were used to evaluate the inhibition properties of CA and compared with the commonly used inhibitors potassium chloride (KCl) and polyamines (HPA and SIAT). The results showed that the inhibition of CA was better than that of KCl, HPA, and SIAT and that it can have a shale hot-rolling recovery of more than 90% at 150 °C, which indicated that CA had higher temperature resistance and longer durability. More importantly, it can be biodegraded as exhibited by the biodegradibility experiment. The inhibition mechanism of CA was studied by particle size distribution, X-ray diffraction, scanning electron microscopy, zeta potential analysis, and contact angle test. The strong inhibition of CA can be attributed to its encapsulation of MMT and shale surfaces. The CA with strongly positively charge was firmly adsorbed on the surface of MMT and shale, which not only neutralized the negative charge of MMT, compressed the diffused electric double layer, but also increased the contact angle of MMT and shale surface which enhancing hydrophobicity of MMT and shale. The hydration swelling and dispersion of MMT and shale were further inhibited. In addition, compatibility experiments showed that CA was compatible with commonly used treatment agents. CA did not affect the rheology of water-based drilling fluids and can reduce fluid loss after aging.
研究领域:
石油工程
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材料科学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2024
·
IF 4.9
Zhaoyu Mao,Xiang Gao,Juan Qiu,Chunchao Chen,Kangwei Gongsun,Changming Bu,Qing Zang,Min Yu,Houyi Ma
A simple two-electrode system was utilized to fabricate a layer of CuCl on the surface of bronze for simulating the "bronze disease". The addition of L-arginine (Arg) reduced the conversion time of the CuCl patina in water from 6 h to 3 h and enhanced the protection efficiency of the transformed patina from 27.9 % to 81.8 %. The alkalinity of Arg and its coordination capacity with Cu 2 + facilitate the transformation of CuCl, modify the transformation mechanism, and alter the morphology and structure of the patina. The immersion experiment further substantiates the stability and self-reinforcing properties of the Arg-transformed patina.
研究领域:
材料科学
·
文物保护
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）