FUEL
·
2025
·
IF 7.5
Zhengyu Yang,Jianmin Li,Yubin Wang,Mengyao Shi,Jide Wang,Changyan Guo
Zeolitic imidazolate frameworks (ZIFs) are rich in accessible and active Lewis acid-base sites and hierarchical pores, making them effective catalysts for the cycloaddition of CO 2 to epoxides under mild conditions. In this study, a facile defect-engineering strategy using acid etching and ligand exchange was developed to convert three-dimensional ZIF-L into layered Br-ZIF-L with a tire-like surface, abundant active sites, and a structure optimized for efficient mass diffusion. This modification enabled the rapid cycloaddition of CO 2 to propylene oxide under mild conditions (1 MPa and 100 °C for 2 h). The resulting cyclic carbonate was obtained in 92 % yield and 100 % selectivity. Additionally, Br-ZIF-L exhibited excellent chemical stability without a loss of catalytic activity after six consecutive cycles, highlighting its potential as a high-performance catalyst for CO 2 conversion. The developed catalytic system exhibited a conversion rate of >90 % for five different substituted epoxides. This study introduces an efficient approach for synthesizing cyclic carbonates via CO 2 fixation under mild conditions.
研究领域:
材料科学
·
化学工程
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产品关联
DOI
高影响因子
WORLD JOURNAL OF MICROBIOLOGY & BIOTECHNOLOGY
·
2025
·Vol. 41
·期 4
·1-15
·
IF 4.2
Zhao Jing-yi,Gao Fan,Wu Mengru,Li Yang,Chen Yong,Xiao Zijun
Enantiopure ( S )-2-methylbutanoic acid [( S )-2-MBA] is a high-value chiral compound with applications in fragrances, pharmaceuticals, and agrochemicals. However, conventional chemical synthesis lacks stereoselectivity, while existing biosynthetic methods suffer from low yield and purity. Here, we report a novel microbial process using Bacillus spizizenii ATCC 6633 for efficient ( S )-2-MBA production via L-isoleucine catabolism. Through targeted screening of rhizospheric soil isolates and Bacillaceae strains, ATCC 6633 demonstrated superior performance, producing 3.67 g/L ( S )-2-MBA with 99.32% enantiomeric excess ( ee ) under optimized conditions (45 °C, 8% inoculation, 5 g/L glucose, and 8 g/L L-isoleucine). A 58.92% conversion efficiency was achieved, and a simplified purification process recovered 63.90% product with 97.32% purity. Mechanistic studies suggested glucose depletion triggered ( S )-2-MBA accumulation, aligning with starvation-induced secondary metabolism. This cost-effective, eco-friendly approach eliminates racemic separation steps and harsh reagents, positioning ATCC 6633 as a promising biocatalyst for sustainable ( S )-2-MBA production.
研究领域:
生物化学
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微生物学
·
有机化学
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产品关联
DOI
PubMed
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
·
2024
·
IF 5.6
Mujeeb Alam,Danping Jiang,Huan Zhang,Lei Zhang,Faiqa Nadeem,Nadeem Tahir,Chaoyang Lu,Quanguo Zhang
Photo-fermentation offers a promising roadmap for hydrogen production through their ability to harness light energy, however, its lower conversion efficiency is the major bottleneck for its realization. This study investigates the catalytic role of wideband gap nano-photocatalysts (SiC, ZnO, and SnO 2 ) in enhancing hydrogen generation from Arundo donax L. Physio-optical characteristics of SiC, ZnO, and SnO 2 nano-photocatalysts were assessed through SEM, XRD, and FT-IR which confirmed that incorporated nano-photocatalysts are spherical with uniform size distribution and there is no secondary phase. Hydrogen production experiments with varying nano-photocatalyst concentrations revealed that the maximum hydrogen yield of 104 and 98.83 mL/g was achieved with SiC and ZnO, respectively, at loading concentration of 200 mg/L, whereas 69.30 mL/g were observed with 100 mg/L of SnO 2 . The incorporation of SIC, ZnO, and SnO 2 nano-photocatalyst permitted to increase the hydrogen content in overall gas production by 41 %, 37.34 %, and 18.26 % as compared to the control group. The increase in hydrogen production is related to the enhanced e-h pair separation lifetime of SiC, confirmed from PL spectroscopy. Addition of SiC caused a longer availability of electrons that helped to increase the metabolic rate by 38 % and 40.29 % in energy conversion efficiency (ECE). ANOVA results revealed significant differences between the control and maximum values of CHP, HC%, byproducts, and ECE. Tukey pairwise comparisons showed that SiC and ZnO had non-significant differences at 200 mg/L but both significantly outperformed SnO 2 at 100 mg/L. Thus, the selection of suitable catalysts photocatalysts with enhanced e-h pair separation lifetime may offer promising prospects for sustainable energy technologies by enhancing biohydrogen production.
研究领域:
生物技术
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可再生能源
·
光发酵
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产品关联
DOI
高影响因子
Frontiers in Bioengineering and Biotechnology
·
2025
·
IF 4.8
Xiuli Cheng,Xiangyu Zhou,Wenping Wang,Jing Chen,Yikun Cao,Jia Wen,Jin Hu
Sophora alopecuroides L. empyreumatic oil (SoA oil) exhibits therapeutic potential for psoriasis and eczema but suffers from poor skin permeability and formulation challenges. To overcome these limitations, a nanoemulsion (NE) gel was developed. The NE was optimized using pseudo-ternary phase diagrams and characterized for droplet size, polydispersity index (PDI), zeta potential, and rheological properties. Skin permeability and retention were assessed in vitro using Franz diffusion cells, with oxymatrine quantified by HPLC. In vivo skin irritation was tested on rabbit dorsal skin, and anti-biofilm activity was evaluated against Staphylococcus aureus (S. aureus) and methicillin-resistant S. aureus (MRSA). A final concentration of 5% SoA oil in the NE formulation was used for subsequent studies. The optimized SoA oil NE (the NE) had a mean droplet size of 53.27 nm, PDI of 0.236, and zeta potential of −38.13 mV. Adding 2% carbomer 940 (CP940) to the gel enhanced viscoelasticity. The NE showed superior skin permeability and higher cutaneous retention of oxymatrine. SoA oil caused moderate irritation to the skin of rabbits, while the other two formulations did not. The NE demonstrated enhanced biofilm inhibition against S. aureus at 0.09766 mg/mL, with an 8.9% rate surpassing SoA oil (2.0%) and SoA oil NE gel (the gel, 4.0%). At 12.50 mg/mL, the NE and the gel achieved slightly higher inhibition rates (81.7% and 82.1%, respectively) than SoA oil (78.3%). Notably, the NE showed significantly greater anti-biofilm effects against MRSA within the concentration range from 0.09766 to 3.12 mg/mL (P < 0.001). In mature biofilm clearance against S. aureus, the NE demonstrated a clearance rate of 4.9% at 0.09766 mg/mL, while SoA oil and the NE gel achieved clearance rates of 2.3% and 0.8%, respectively. At a higher concentration of 12.50 mg/mL, the clearance rate for the NE increased to 38.1%, significantly outperforming SoA oil (29.1%) and the NE gel (36.4%). Against MRSA, the NE and the gel displayed significantly improved clearance at 12.50 mg/mL (42.7% and 43.9%, respectively) compared to SoA oil (31.9%) (P < 0.0001). These findings highlight the potential of nanotechnology-driven delivery systems to improve the clinical application of herbal extracts for treating biofilm-associated dermatological infections.
研究领域:
药剂学
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皮肤病学
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微生物学
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产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry B
·
2016
·Vol. 5
·期 3
·511-516
·
IF 4.872
Yifan Wang,Ying Xiao,Guorong Gao,Jing Chen,Ruixia Hou,Qiang Wang,Li Liu,Jun Fu
Graphene composite hydrogels have wide potential applications as biomaterials. Herein, L-cysteine was used to reduce graphene oxide (GO) into hydrogels. Systematic investigations by FTIR, Raman spectroscopy, TEM, and other methods reveal that the reduced graphene oxide (rGO) nanosheets are likely bridged by L-cysteine molecules, forming porous hydrogels with the rGO nanosheets stacked into layered structures on the walls. Such layered structures, as well as the reduction, are critical for the improvement of conductivity by four to five orders of magnitude in comparison to graphene oxide. In vitro cell culture experiments demonstrate excellent cell adhesion and growth on these reduced graphene oxide hydrogels. These conductive rGO hydrogels may find applications in electrical stimulation to facilitate cell adhesion and growth.
研究领域:
生物材料学
·
细胞生物学
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DOI
PubMed
高影响因子
Advanced Sensor Research
·
2023
·Vol. 2
·期 5
·2200014
·
IF 0
Yangwei Li,Jing Qian,Yuanyuan Zhang,Ting Zeng,Qijin Wan,Nianjun Yang
In this study, metal–organic framework (MOF) nanoparticles of UiO-66 are integrated with expanded graphite (EG) (UiO-66/EG) by a facile solvothermal approach. The advantages of this nanocomposite UiO-66/EG overcome the poor electronic conductivity and slow diffusion of MOFs for their electrochemical applications. Through electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and electrochemical techniques, the morphology, surface area, and physicochemical properties of this UiO-66/EG nanocomposite are characterized. The UiO-66/EG nanocomposite exhibits superior sensing performance over the UiO-66 and EG when used for nitrite and L-cysteine determination. This includes less positive oxidation potentials and enhanced oxidation currents. Using the UiO-66/EG nanocomposite, the nitrite oxidation peak current is linear with a concentration range of 0.20 μ m to 13.15 m m with the lowest limit of detection (LOD) of 0.06 μ m ( S / N = 3). Meanwhile, superior performance is demonstrated for L-cysteine monitoring, where the oxidation peak current is linear over the L-cysteine concentration in the range of 0.5–250 μ m and of 0.25–3.50 m m and a LOD of 0.28 μ m ( S / N = 3). This UiO-66/EG/GCE nanocomposite is successfully exploited to detect nitrite in food samples and to measure L-cysteine in juice samples. Therefore, the proposed sensing platform enables the fabrication of high-performance electrochemical sensors to accurately quantify nitrite and L-cysteine in complex matrixes.
研究领域:
分析化学
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材料科学
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电化学传感器
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DOI
CURRENT ORGANIC SYNTHESIS
·
2024
·Vol. 21
·期 1
·47-60
·
IF 1.7
Zhang Cuizhi,Fan Yanchao,Wang Sijia,Liu Shaojie,Chu Xiaomeng,Tang Erjun
Introduction: L-proline is an efficient chiral small-molecule organocatalyst for the direct asymmetric aldol reaction between unmodified acetone and a variety of aldehydes. Methods: However, it is difficult to separate from the reaction medium for reuse. In this work, polyacrylic
acid (PAA) supported The acylation reaction between L-hydroxyproline and PAA prepared lproline (P(AA-co-PA)) catalysts with various catalyst loadings. Fourier characterized them transforms infrared spectroscopy, nuclear magnetic resonance spectrum, gel permeation chromatography and thermogravimetry
analysis. Results: These macromolecular catalysts were used to catalyze acetone and benzaldehydes' direct asymmetric aldol reaction. The influence of the catalyst structure on the catalytic performance was studied, and the reaction conditions were optimized. Conclusion: The results
showed that P(AA-co-PA) with 50 mol% catalyst loading had excellent catalytic performance, much higher than that of L-proline and L-hydroxyproline. Its recovery was achieved by simple filtration. After being reused 7 times, its catalytic performance was still higher than that of L-proline.
研究领域:
有机化学
·
催化化学
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DOI
高影响因子
JOURNAL OF POLYMERS AND THE ENVIRONMENT
·
2022
·Vol. 31
·期 1
·1-12
·
IF 4.705
Yuan Yuka,Fu Zhe,Liu Yudong,Liu Kai,Hua Jing
Poly (L-lactic acid) (PLLA) suggests attractive biomedical applications in drug releasing system, surgical suture, bone fixing and tissue repairing due to its degradable and biocompatible benefits. However, currently developed catalysts with high toxicity and currently reported PLLA with uncontrollable crystallinity are detrimental for the environmental protection and human health. Herein, we proposed a novel and effective approach to synthesizing PLLA using environmentally-friendly bio-based phenol-substituted triisobutylaluminum as the catalyst. The effects of the chemical structures of various bio-based phenols on the polymerization activity and stereoregularity of PLLA were explored in detail. The increased steric hindrance of bio-based phenols was beneficial for the polymerization activity of PLLA. The resultant PLLA exhibited an ultrahigh monomer conversion efficiency up to 98.32% among the highest value of reported PLLA. Moreover, the PLLA also demonstrated quick polymerization rate (< 5 h) and low polymerization temperature (< 100 °C), with controllable polymer crystallinity (36 ~ 46%) and number average molecular weight (8400 ~ 16,000 g mol −1 ). Consequently, the strategy and results collectively represent a significant advance toward the preparation of high-performance degradable and biocompatible PLLA.
研究领域:
材料科学
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生物医学工程
·
高分子化学
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DOI
高影响因子
Journal of Analysis and Testing
·
2019
·Vol. 3
·期 3
·277-285
·
IF 0
Li Xinxue,Huang Qingwei,Li Wei,Zhang Jinli,Fu Yan
Abstract N -Acety-L-cysteine (NAC), enriched with multiple electron-rich groups involving –SH, –C=O, and –COOH, exhibits strong affinities to transition metal ions. Herein, NAC was adopted as the stabilizing agent to synthesize a series of peroxidase-like Pt nanoclusters (NCs) with different physicochemical properties. Both the cluster size and the charge state of NAC–Pt NCs are highly dependent upon the molar ratio of [K 2 PtCl 4 ]/[NAC], contributing to different peroxidase mimicking activities. The most active Pt nanozyme (~ 1.7 nm), composed of 60% metallic Pt 0 and 40% positively charged Pt 2+ respectively, exhibits the K m of 0.132 mM for 3,3′,5,5′-tetramethylbenzidine and 35 mM for H 2 O 2 . Based on the heparin-activated enzymatic activity of NAC–Pt at pH 6.0, an ultrasensitive test was established for quantitative determination of heparin, giving the linear response of 0.5–20 μg/mL as well as the limit of detection of 2 × 10 −3 μg/mL. This proposed method is also applicable in biological fluid for practical applications. Such a colorimetric method possesses several advantages involving high sensitivity, short response, eco-friendly synthesis, low consumption of material and energy, free of expensive instrument, as well as simple operation. Graphic abstract
研究领域:
纳米技术
·
分析化学
·
生物化学
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DOI
Foods
·
2021
·Vol. 10
·期 11
·2819
·
IF 4.35
Huibing Chi,Meirong Chen,Linshu Jiao,Zhaoxin Lu,Xiaomei Bie,Haizhen Zhao,Fengxia Lu
L-asparaginase (E.C.3.5.1.1) is a well-known agent that prevents the formation of acrylamide both in the food industry and against childhood acute lymphoblastic leukemia in clinical settings. The disadvantages of L-asparaginase, which restrict its industrial application, include its narrow range of pH stability and low thermostability. In this study, a novel L-asparaginase fromMycobacterium gordonae(GmASNase) was cloned and expressed inEscherichia coliBL21 (DE3). GmASNase was found to be a tetramer with a monomeric size of 32 kDa, sharing only 32% structural identity withHelicobacter pyloriL-asparaginases in the Protein Data Bank database. The purified GmASNase had the highest specific activity of 486.65 IU mg−1at pH 9.0 and 50 °C. In addition, GmASNase possessed superior properties in terms of stability at a wide pH range of 5.0–11.0 and activity at temperatures below 40 °C. Moreover, GmASNase displayed high substrate specificity towards L-asparagine with Km, kcat, and kcat/Km values of 6.025 mM, 11,864.71 min−1and 1969.25 mM−1min−1, respectively. To evaluate its ability to mitigate acrylamide, GmASNase was used to treat potato chips prior to frying, where the acrylamide content decreased by 65.09% compared with the untreated control. These results suggest that GmASNase is a potential candidate for applications in the food industry.Keywords:L-asparaginase;acrylamide;Mycobacterium gordonae;thermal stability
研究领域:
食品科学
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酶学
·
生物技术
·
生物化学
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DOI
PubMed
高影响因子
AICHE JOURNAL
·
2025
·
IF 4
Xiao-Ling Tang,Kang Zhao,Teng-Kun Huang,Bai-Hua He,Xu-Gang Zhang,Zhi-Qiang Liu,Yu-Guo Zheng
O -Succinyl- L -homoserine mercaptotransferase (MetZ) is a key enzyme for the synthesis of L -methionine. However, the limited tolerance to high concentrations of substrate methyl mercaptan sodium restricts its industrial applications, while the “trade-off” between activity and stability has always been a challenge for protein engineering. To address this problem, a strategy of dynamic network rigidification-local flexibility regulation was applied in this study to engineer the enzyme from Chromobacterium violaceum ( Cv MetZ). Through consensus sequence analysis and structure-guided design, the hotspot amino acid residues were anchored for mutagenesis. The best mutant T59I/T119Y/A241T was obtained with synergistic enhancement of activity and stability. The half-life ( t 1/2 ) of whole cells harboring the mutant was increased from 3.3 and 1.3 h to 20.6 and 7.2 h, in the presence of 5% and 10% methyl mercaptan sodium, respectively. The engineered enzyme was successfully immobilized with ideal usability, which laid the foundation for efficient and scale-up bioproduction of L -methionine.
研究领域:
酶工程
·
蛋白质设计
·
结构生物学
·
工业生物技术
·
生物催化
·
代谢工程
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产品关联
DOI
高影响因子
ACS Catalysis
·
2022
·
IF 13.7
Shuchao Jiang,Junxia Yang,Shengliang Zhai,Ling Zhang,Rui Tu,Tie Yu,Dong Zhai,Lei Sun,Weiqiao Deng,Guoqing Ren
Formic acid (FA)/formate as a promising liquid organic hydrogen carrier exhibits great potential for future energy supplies. However, FA/formate-based hydrogen storage and release, which can be operated under ambient conditions, is challenging but attractive. Here, we report an ambient hydrogen storage and release process that uses the acidity and alkalinity of the reaction solution to control hydrogen production or consumption via an l-arginine-functionalized active carbon-supported PdAu alloy catalyst (PdAu/AC-LA). By regulating the LA loading and Pd/Au ratio, we obtain the optimal catalytic activity with turnover frequency (TOF) of 1760 h–1 for FA dehydrogenation under acidic conditions and 138 h–1 for CO2 hydrogenation under alkaline conditions. Comprehensive characterizations, including X-ray photoelectron spectroscopy (XPS), CO2 temperature-programmed desorption (CO2-TPD), and HCOO– adsorption experiments, reveal that the synergistic effect between PdAu alloy and strongly basic l-arginine enhances catalytic activity by regulating the adsorption of reactants. Our work, as a successful example of FA/formate-based hydrogen storage and release under ambient conditions, may aid putting the safe and energy-saving use of hydrogen into practice.
研究领域:
化学工程
·
催化科学
·
能源技术
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）