INTERNATIONAL JOURNAL OF FOOD SCIENCE AND TECHNOLOGY
·
2021
·Vol. 56
·期 12
·6591-6600
·
IF 3.713
Jiali Yang,Tengfei Wang,Jianbing Di,Yaping Liu,Xiaoling Hao,Yu Wang
Summary Although several studies have shown the ability of l -glutamate (glutamate) to mitigate the stress imposed by pathogens, the underlying mechanism is still in its infancy. To gain further knowledge, this study focussed on the effect of glutamate on primary nitrogen and carbon metabolisms during apple- Penicillium expansum interaction. The obtained result showed that glutamate could effectively restrict blue mould rot development in apples, but had no direct impact on fungal growth in vitro . The application of glutamate increased the level of nitrogen in apples, resulting in a disrupted balance of carbon and nitrogen. Consistently, the key enzymes glutamine synthetase (GS) and glutamate synthase (GOGAT) involved in the GS/GOGAT cycle, and the deaminating activity of glutamate dehydrogenase (GDH), forming 2-oxoglutarate and ammonium from glutamate, were promptly stimulated by glutamate. Interestingly, glutamate led to considerable consumption of the tricarboxylic acid (TCA) cycle intermediates, such as isocitric acid and citric acid, accompanied by the enhancement of malate dehydrogenase and succinate dehydrogenase activities. Collectively, exogenous application of glutamate might confer blue mould resistance in apples, at least in part, by redirecting host’s primary nitrogen and carbon metabolisms, such as the activation of the GS/GOGAT cycle, deaminating activity of GDH and the TCA cycle.
研究领域:
植物病理学
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食品科学
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产品关联
DOI
高影响因子
MONATSHEFTE FUR CHEMIE
·
2019
·Vol. 150
·期 7
·1349-1354
·
IF 1.501
Li Yunhao,Liu Shiquan
Abstract A porous silica gel with both COOH and NH 2 groups was synthesized in one pot by the addition of l -glutamic acid ( l -GA) into a synthesis medium consisting of tetraethyl orthosilicate, water, ethanol, and 1-butylamine. The inclusion of l -GA in the as-synthesized product ( l -GA-SiO 2 ) was evidenced by FT-IR and TG measurements. The l -GA was chemically bonded with silica as indicated by the shift of FT-IR bands at 1510 and 1400 cm −1 in the spectrum of l -GA to higher wavenumbers of 1540 and 1460 cm −1 in the one of l -GA-SiO 2 . The TG analysis showed that the l -GA-SiO 2 had an increase of weight loss by 5.6% due to the decomposition of the included l -GA which was centered at around 313 °C, suggested by a new peak in the DTG curve. Compared with the one synthesized without l -GA, the l -GA-SiO 2 was more aggregated with smaller surface area. However, the latter showed a higher removal efficiency by 17.1% toward zinc ions in water than the former and the adsorbed ions were hardly released again into water from the used adsorbent. Graphical abstract
研究领域:
材料科学
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环境科学
·
化学工程
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DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2014
·Vol. 38
·期 8
·3395-3400
·
IF 3.159
Ai-Jun Wang,Jing-Jing Lv,Dan-Ling Zhou,Xuexiang Weng,Su-Fang Qin,Jiu-Ju Feng
In this report, ultrathin worm-like Au nanowires were constructed with the assistance of L-glutamic acid as a structure-directing agent and a weak stabilizing agent. The morphology of the Au products was found to be strongly dependent on the experimental parameters such as the amount of L-glutamic acid, as well as the reaction temperature. This synthesis was a seedless process, without using any template, surfactant, or toxic organic agent. Furthermore, the as-prepared Au nanowires were applied to facilely fabricate porous Au films with controllable thickness via simple gravity settling. The Au films showed high surface-enhanced Raman scattering (SERS) enhancement, using 4-mercaptobenzoic acid as a model probe. The Au films may be promising candidates for SERS sensing. This strategy provides an environmental friendly way for the preparation of various metal nanostructures with novel morphologies and useful applications.
研究领域:
材料科学
·
化学
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产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2024
·
IF 7.4
Yuxin Wang,Yueqi Chen,Fengjun Shan,Tingting Zhang,Zhenbin Zhang,Meijun Liu
Hexavalent chromium (Cr(VI)) pollution in aquatic environments has triggered constant worries. As one of the popular adsorbents, graphene oxide (GO) still confronts shortcomings in the Cr(VI) removal, including easy aggregation, limited adsorption amounts, monotonous type of functional groups, constant negative charge and unable valence conversion. Herein, L-glutamic acid (L-Glu) was utilized for GO functionalization through the solvothermal method to fabricate L-Glu/GO with the trait of anti-stacking for overcoming the above-mentioned drawbacks. Results proved that L-Glu/GO possessed the relatively large specific surface area and average pore diameters, various functional groups and variable surface charges. The as-prepared L-Glu/GO exhibited satisfying adsorption amounts with the changeable acid environment, adsorbent dosages and initial Cr(VI) concentrations. Besides, Cr(VI) adsorption process conformed to the pseudo-second-order kinetic model and the Langmuir isotherm model with q m for Cr(Ⅵ) of 71.12 mg·g –1 , almost 27 times higher than that of GO (2.64 mg·g –1 ) in pH = 2. The adsorption thermodynamics result portrayed the adsorption process was a spontaneous endothermic process. Additionally, L-Glu/GO possessed excellent reusability with q e of Cr(Ⅵ) of 57.19 mg·g –1 after five cycles, with the economic cost of ¥0.498·g –1 . More importantly, Cr(VI) was changed into Cr(III) during adsorption to accomplish the toxicity elimination due to existence of amine groups from L-Glu. On the whole, pore filling, anion-π interaction, electrostatic interactions, adsorption-reduction and coordination interaction jointly contributed to the Cr(VI) adsorption. This work provided the strategy for effectively enhancing the Cr(VI) adsorption capacity of GO and deepened the adsorption mechanism towards hazardous metal ions elimination.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
Journal of Materials Chemistry B
·
2018
·Vol. 6
·期 42
·6865-6876
·
IF 4.776
Weijun Zhang,Kunxi Zhang,Shifeng Yan,Jie Wu,Jingbo Yin
A hydrogel with excellent mechanical properties and self-healing ability provides a promising tool for the repair of load-bearing tissues under a dynamic microenvironment. In this study, poly(L-glutamic acid) (PLGA)-based composite hydrogels with good toughness and self-healing ability were fabricated via filling soft self-healing hydrogels into a tough porous hydrogel skeleton. The PLGA-based tough porous hydrogel skeleton was treated by laser ablation to form a uniform porous structure with 85% porosity and 260 μm pore diameter, and the structure formation was reinforced by the hydrophobic assembly mechanism. The resulting hydrogel skeleton possessed good toughness (maximum compressive stress of 0.51 MPa with strain of 80%) and could fully recover after cyclic compression tests. Furthermore, PLGA-based self-healing hydrogels were fabricated based on a Schiff base reaction, followed by being composited with a tough porous hydrogel skeleton. More importantly, the composite hydrogel exhibited a homogenous interpenetrated structure that inherited mechanical strength and the self-healing ability of the two original compositions. These composite hydrogels exhibited a compressive failure stress of 0.21 MPa at a 63% strain, which was 1.3-fold higher than the value of the original porous hydrogel skeleton at 63% strain. The healing percentage gradually reached 81% within 6 h, indicating the good self-healing efficiency. Furthermore, live/dead staining images revealed that 89% of laden cells remained alive after culture for 7 days. Moreover, the composite hydrogel could self-heal even after cell encapsulation. The developed PLGA-based composite hydrogel will be a promising biomaterial for the repair of load-bearing tissues.
研究领域:
材料科学
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生物材料
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组织工程
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产品关联
DOI
PubMed
高影响因子
MICROCHEMICAL JOURNAL
·
2023
·
IF 4.8
Ye Lin,Lingfen Yang,Ying Ma,Jianshan Ye
l -glutamate ( l -Glu) is the basic unit for the synthesis of protein, metabolic substances and chlorophyll, and plays an important role in the carbon and nitrogen metabolism in plants. The in vivo monitoring of l -Glu level is of great significance to study the growth and development of plants. Although a variety of methods have been reported for the in vitro determination of l -Glu, there are very limited research focused on the determination of l -Glu in plants. Here we firstly report a simple method to construct a minitype glutamate sensor for in vivo monitoring of l -glutamate in cucumber. The minitype graphite rod electrode (GRE) allows its application for in vivo monitoring, and modification of Pt nanoparticles (PtNPs) and poly ( m -phenylenediamine) film (PMPD) significantly improves the sensitivity and anti-interference ability, and immobilization of the glutamate oxidase (GluOx) could effectively catalyze the l -Glu into a detectable H 2 O 2 . The resulting l -Glu sensor exhibits a good performance in terms of high sensitivity, good selectivity and excellent stability with a linear range of 2–550 μM and limit of detection (LOD) as low as 0.536 μM. More importantly, the as-developed sensor was successfully applied for the determination of l -Glu in cucumber juice and the in vivo monitoring of l -Glu level in cucumber fruit. We envision that the constructed sensor will show great potentials for studying the growth mechanisms of plants.
研究领域:
植物学
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分析化学
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DOI
高影响因子
Biomaterials Science
·
2019
·Vol. 7
·期 9
·3675-3682
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IF 5.251
Bing Li,Yueming Wu,Wenjing Zhang,Si Zhang,Ning Shao,Weiwei Zhang,Lixin Zhang,Jian Fei,Yidong Dai,Runhui Liu
Proteins are fragile such that even freezing, drying and dehydration may induce their denaturation, aggregation, and activity loss. To protect proteins from these kinds of damage, we prepared two types of amino acid polymers, poly-(L-glutamate)-r-poly-(L-lysine) (PLG-r-PLL) and poly-L-glutamate (PLG), from the efficient ring-opening polymerization of α-amino acid N-carboxyanhydride (NCA) using lithium hexamethyldisilazide (LiHMDS) as the initiator. β-galactosidase (β-Gal) was used in this study to examine the protein protecting effect of the synthesized amino acid polymers during lyophilization. The results indicate that both PLG-r-PLL and PLG exert significant protection on β-Gal during lyophilization and improve the activity of the resulting protein from 40%, without using a protecting agent during lyophilization, to 80% of the original protein activity. Nevertheless, PLG generally performs better than PLG-r-PLL independent of the chain length. Our studies also show that PLG and PLG-r-PLL with a high content of PLG subunits display no observable cytotoxicity and hemolytic effect. Furthermore, dynamic light scattering (DLS) and transmission electron microscopy (TEM) characterization indicate that PLG protects β-Gal upon lyophilization by preventing the aggregation of β-Gal. Our studies demonstrate that amino acid polymers, such as PLG, can exert potent activity for protein stabilization. The easy operation of LiHMDS-initiated and efficient NCA polymerization implies the great potential of this strategy to prepare amino acid polymers quickly for the screening of protein stabilization and mechanism study.
研究领域:
聚合物化学
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生物技术
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药学
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蛋白质工程
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产品关联
DOI
PubMed
高影响因子
CHINESE JOURNAL OF POLYMER SCIENCE
·
2024
·Vol. 42
·期 5
·570-578
·
IF 4.1
Sun Xiao-Fei,Zhang Xu,Song Shu-Ping,Yao Ya-Qun,Zhang Yan,Wang Cheng-Liang,Sun Jing-Jiang,Wang Qing-Fu
L -glutamic acid (LA) is a bio-based, non-toxic, environmentally friendly material derived from biomass. The present study reports the application of Passerini three-component polymerization (P-3CP) for the straightforward preparation of LA-based light-responsive polyesters (PLTDs) under mild conditions. PLTDs with molar masses up to 8500 g/mol and high yields exceeding 90% are obtained. The chemical structures and light-responsive self-immolative behavior of PLTDs are comprehensively characterized by employing ultraviolet-visible (UV-Vis) spectroscopy, size exclusion chromatography (SEC), nuclear magnetic resonance (NMR) spectroscopy, and liquid chromatography mass spectrometry (LC-MS). Meanwhile, monodisperse PLTD-based doxorubicin-loaded nanoparticles (PLTD-DOX-NP) (size=193 nm, PDI=0.018) are formulated by nanoprecipitation method. Upon light-induced depolymerization, the PLTD-DOX-NP undergoes rapid decomposition, resulting in a burst release of 80% cargo within 13 s. Furthermore, according to biological toxicity tests, the PLTD-NP possesses adequate biosafety, both before and after irradiation. Overall, the incorporation of P-3CP with biorenewable LA-based monomer adheres to the principles of green chemistry, significantly simplifying the synthetic pathway of light-responsive polymers.
研究领域:
材料科学
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生物医学工程
·
绿色化学
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DOI
高影响因子
MACROMOLECULAR BIOSCIENCE
·
2020
·Vol. 21
·期 1
·2000192
·
IF 3.416
Haiyang Yu,Yanli Bao,Caina Xu,Li Chen,Zhaohui Tang
Despite the polymeric vascular disrupting agent (poly( L -glutamic acid)- graft -methoxy poly(ethylene glycol)/combretastatin A4) nanoparticles can efficiently inhibit cancer growth, their further application is still a challenge owing to the tumor recurrence and metastasis after treatment. In this study, two poly( L -glutamic acid)-drug conjugates for chemo-and photodynamic combination therapy are fabricated. PLG- g -mPEG-CA4 nanoparticles are prepared by combretastatin A4 (CA4) and poly( L -glutamic acid)- graft -methoxy poly(ethylene glycol) (PLG- g -mPEG) using the Yamaguchi esterification reaction. PLG- g -mPEG-TPP (TPP: 5, 10, 15, 20-tetraphenylporphyrin) nanoparticles are constructed using PLG- g -mPEG and amine porphyrin through condensation reaction between carboxyl group of PLG- g -mPEG and amino group of porphyrin. The results showed that PLG- g -mPEG-CA4 nanoparticles have good antitumor ability. PLG- g -mPEG-TPP nanoparticles can produce singlet oxygen under the laser irradiation. Moreover, the combined therapy of PLG- g -mPEG-CA4 and PLG- g -mPEG-TPP nanoparticles has higher antitumor effect than the single chemotherapy or the single photodynamic therapy in vitro. The combination of CA4 nondrug and photodynamic therapy provides a new insight for enhancing the tumor therapeutic effect with vascular disrupting agents and other therapy.
研究领域:
药学
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肿瘤学
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生物材料学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Food Bioscience
·
2021
·
IF 4.24
Li Yuan,Yunfei Kong,Weijun Leng,Yanmin Wang,Wengang Jin,Ruichang Gao
The myosin aggregation of b.ighead carp ( Aristichthys nobilis ) induced by heating and the physical structure of surimi gels were changed using L-Glu. L-Glu increased the solubility of myosin regardless of heating or low/high ionic strength . Compared to myosin, the hydrophobicity of myosin with L-Glu at low ionic strength increased significantly, however there was no difference between myosin and myosin with L-Glu at high ionic strength. Atomic force microscopy and scanning electron microscopy results showed that L-Glu suppressed myosin aggregation, forming a honeycomb-like network after a two-step heating. Consequently, the suppression by L-Glu of myosin aggregation changed the physical properties of surimi gels. The water holding capacity of surimi gels with L-Glu increased significantly, but the hardness decreased. This study suggested that the influence of myosin aggregation induced using L-Glu increased ion-dipole interactions, hydrogen bonds and electrostatic repulsions, which changed the microstructure of surimi. L-Glu could be used as an additive to soften surimi gels with low salt for those with difficulty in chewing .
研究领域:
食品科学
·
生物化学
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产品关联
DOI
高影响因子
APPLIED MICROBIOLOGY AND BIOTECHNOLOGY
·
2023
·Vol. 107
·期 21
·6497-6506
·
IF 5
Liu Kun,Liu Yan,Li Xiangfei,Zhang Xiushan,Xue Zhenglian,Zhao Ming
Abstract The whole-cell catalysis strategy of alpha-ketoglutaric acid (α-KG) production from L-glutamic acid (L-Glu) using recombinant Escherichia coli , in which L-glutamate oxidase (LGox) was over-expressed, has replaced the traditional chemical synthesis strategy. However, large amounts of toxic by-product, H 2 O 2 , should be eliminated through co-expressing catalase (Cat), thus severely increasing burden in cells. To efficiently and economically produce α-KG, here, the genes SpLGox (from Streptomyces platensis NTU3304) and SlCat (from Streptomyces lividans TK24) were inserted into the low-dosage-IPTG (Isopropyl β-D-Thiogalactoside) inducible expression system, constructed in our previous work, in E. coli , respectively. Besides, a double-strain catalysis system was established and optimized to produce α-KG, and the productivity of α-KG was increased 97% compared with that through single strain catalysis. Finally, a double-strain cultivation strategy was designed and employed to simplify the scale-up fermentation. Using the optimized whole-cell biocatalyst conditions (pH 7.0, 35 °C), majority of the L-glutamic acid was transformed into α-KG and the titer reached 95.4 g/L after 6 h with the highest productivity at present. Therefore, this strategy may efficiently and cost-effectively produce α-KG, enhancing its potential for industrial applications. Key points
• SpLGox and SlCat were over-expressed to catalyze L-Glu to α-KG and eliminate by-product H
2
O
2
, respectively.
• Double-strain cultivation and catalysis system can efficiently and cost-effectively produce α-KG from L-Glu.
研究领域:
生物工程
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代谢工程
·
酶学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Biomaterials Science & Engineering
·
2020
·
IF 4.152
Qi Wang,Zhen Shi,Yufeng Shou,Kunxi Zhang,Guifei Li,Pengfei Xia,Shifeng Yan,Jingbo Yin
Supramolecular hydrogels formed by noncovalent bonds are attractive “smart” materials, which can rapidly respond to external stimuli. However, only a handful of supramolecular hydrogels is applicable in tissue engineering, due to the instability and poor mechanical strength of noncovalent cross-linking hydrogels. Thus, a rigid and stable supramolecular hydrogel has been developed based on poly(l-glutamic acid) and 2-ureido-4[1H]pyrimidinones (UPy), and the UPy stacks are noncovalent cross-linking interactions. The hydrogels show excellent mechanical strength and stability, in sharp contrast to noncovalent hydrogels cross-linked by UPy dimers and covalent hydrogels cross-linked by esterification. The hydrogels also exhibit remoldability, self-healing, and thermoplastic printing characteristics, which are caused by the reversible supramolecular property of UPy stacks. Also, the formation of hydrogels dependent on UPy stacks is further investigated by atomic force microscope, small-angle X-ray scattering, in situ X-ray diffraction, circular dichroism, and UV–vis spectroscopies. Finally, the hydrogels show commendable biocompatibility and degradability, which have high potential applications in regenerative medicine.
研究领域:
材料科学
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生物医学工程
·
再生医学
✓ 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）