JOURNAL OF ALLOYS AND COMPOUNDS
·
2017
·
IF 3.133
Yuanfeng Wu,Xianghai Song,Fufeng Cai,Guomin Xiao
A series of Ce-NiO catalysts prepared by co-precipitation method were tested for glycerol transesterification with diethyl carbonate (DEC) to produce glycerol carbonate (GC). The microstructural and physicochemical properties of the catalysts were determined by XRD , XPS , SEM, EDX, CO 2 -TPD, N 2 -adsorption, FT-IR, and TG-DTG. The results showed that the particle size (100–350 nm) of the Ce-NiO was smaller than that of pure NiO (400–900 nm), suggesting addition of Ce in the catalyst synthesis could lessen the aggregation or facilitate the dispersion of NiO particles. The highest catalyst activity was observed over the Ce-NiO catalyst with Ce/Ni atomic ratio of 0.2 and calcined at 400 °C. 94.14% of glycerol conversion and 90.95% selectivity to GC were obtained over this catalyst under the optimum conditions (5 wt.% catalyst of glycerol, 85 °C, 8 h, glycerol/DEC ratio of 1:3). This catalyst can be reused up to three cycles with a slight decrease in its catalytic activity. It was found the well dispersed NiO particles and the strong basic sites derived from the substitution of Ce 4+ by Ni 2+ in the CeO 2 lattices synergistically promoted the glycerol conversion.
研究领域:
催化化学
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材料科学
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可再生能源
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DOI
高影响因子
JOURNAL OF BIOLOGICAL CHEMISTRY
·
2020
·Vol. 295
·期 19
·6425-6446
·
IF 4.238
Chengmeng Jin,Xiaobing Zhu,Hao Wu,Yuqi Wang,Xun Hu
Phosphoglycerate kinase 1 (PGK1) plays important roles in glycolysis, yet its forward reaction kinetics are unknown, and its role especially in regulating cancer cell glycolysis is unclear. Here, we developed an enzyme assay to measure the kinetic parameters of the PGK1-catalyzed forward reaction. The Km values for 1,3-bisphosphoglyceric acid (1,3-BPG, the forward reaction substrate) were 4.36 μm (yeast PGK1) and 6.86 μm (human PKG1). The Km values for 3-phosphoglycerate (3-PG, the reverse reaction substrate and a serine precursor) were 146 μm (yeast PGK1) and 186 μm (human PGK1). The Vmax of the forward reaction was about 3.5- and 5.8-fold higher than that of the reverse reaction for the human and yeast enzymes, respectively. Consistently, the intracellular steady-state concentrations of 3-PG were between 180 and 550 μm in cancer cells, providing a basis for glycolysis to shuttle 3-PG to the serine synthesis pathway. Using siRNA-mediated PGK1-specific knockdown in five cancer cell lines derived from different tissues, along with titration of PGK1 in a cell-free glycolysis system, we found that the perturbation of PGK1 had no effect or only marginal effects on the glucose consumption and lactate generation. The PGK1 knockdown increased the concentrations of fructose 1,6-bisphosphate, dihydroxyacetone phosphate, glyceraldehyde 3-phosphate, and 1,3-BPG in nearly equal proportions, controlled by the kinetic and thermodynamic states of glycolysis. We conclude that perturbation of PGK1 in cancer cells insignificantly affects the conversion of glucose to lactate in glycolysis.
研究领域:
生物化学
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癌症生物学
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细胞代谢
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酶学
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产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2018
·
IF 4.946
Nanjing Zhong,Weilin Chen,Liyan Liu,Hongxiao Chen
In this study, mesoporous silica SBA-15 was modified by organic functional groups through silanization. Series of organosilane compounds were grafted onto the SBA-15, and the obtained functionalized carriers were then used to immobilize the lipase from Rhizomucor miehei (RML). The enzymatic properties of the obtained immobilized RML samples were evaluated, and the catalytic efficiencies in glycerolysis of triacylglycerols (TAG) reaction were studied. Compared with the parent SBA-15 immobilized RML, the organic modification gave a maximum improvement of enzymatic activity from 200.00 to 13211.11 U/g; in addition, TAG conversion and diacylglycerols (DAG) content increased from 21.28 to 84.24% and 15.45 to 59.03% respectively. The organic modification also decreased the sensitivity of immobilized RML in extreme pH values and increased their thermostability.
研究领域:
生物化学
·
酶工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FUEL
·
2023
·
IF 7.4
Ruru Zhou,Boyong Ye,Zhaoyin Hou
Biodiesel is a sustainable and renewable fuel, which is popularly recommended as a substitute for traditional fossil resources. However, the rapidly growing production of biodiesel in past decades has brought the formation of surplus glycerol. In this work, glycerol-derived acetins were synthesized via transesterification of glycerol with methyl acetate over a hierarchical porous polymeric solid acid catalyst ( h SPB- x ) which was prepared in a facile method. It was found that h SPB-2 was highly active and stable for this transesterification reaction. The highest yield of acetylglycerols reached 126.1 g-acetins/g-cat/h at 100 °C, while the turnover frequency of acid sites in h SPB-2 attained 330.1 h −1 at the beginning of the reaction. And h SPB-2 was stable for 5-time recycles without obvious deactivation. Characterization results indicated that the excellent performance of h SPB-2 could be attributed to its high acidity (2.77 mmol/g), large surface area (872 m 2 /g), regular hierarchical pore channels, and good thermal stability.
研究领域:
化学工程
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可再生能源
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS A-GENERAL
·
2022
·
IF 5.723
Weilu Wang,Xiangke Zeng,Shan He,Haidong Zhang,Guangming Jiang,Yang He,Yunqi Liu,Fan Dong,Xianming Zhang,Steven L. Suib
A series of Fe-doped alumino-borate catalysts (18 % Fe-PKU-1) with a range of crystalline qualities has been obtained by varying synthesis conditions. Based on Angle-resolved X-ray Photoelectron Spectroscopy, pyridine adsorption infrared spectroscopy, and potentiometric titration, crystalline quality is correlated as volcano trends with the surface composition and electronic structure of Fe-PKU-1, especially for the boron species. Through the systematic change of synthesized conditions, the catalyst with the appropriate crystalline quality shows the highest surface compositions of boron and oxygen vacancies. This leads to strong surface Lewis acidity and results in the high catalytic performance of glycerin ketalization, 97 % conversion and 99 % selectivity in DL-1,2-Isopropylideneglycerol (Solketal).
研究领域:
催化
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材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
GREEN CHEMISTRY
·
2022
·Vol. 24
·期 24
·9721-9733
·
IF 11.034
Lin Huang,Xinhao Yu,Lei Huang,Xingtian Zhang,Li Gu,Yongyong Cao,Wei Li,Jing Hu,Xuebo Cao
With the development of the biodiesel industry, the annual production of the byproduct glycerol has increased to a level of nearly millions of tons. Efficient and clean utilization of glycerol is thus urgent and profitable. Direct glycerol fuel cells (DGFCs) capable of selective oxidation of glycerol and co-generation of electricity and high-value added chemicals seem to be the most compelling technique. Unfortunately, selective and durable electrocatalysts for fabricating DGFCs are still not available so far. Herein, ternary Pt–Pd–Ag alloy nanowires (NWs) are designed and synthesized under the direction of the d-band theory. The resulting Pd–Pt–Ag NWs exhibit significant activity towards the glycerol electro-oxidation reaction (GOR) and oxygen reduction reaction (ORR) in an alkaline medium, which outperforms the bimetallic Pt–Ag alloy NWs and the commercial Pt/C benchmark. Moreover, a homemade DGFC based on bifunctional Pd–Pt–Ag NW anode and cathode can achieve a peak power density of 13.7 mW cm−2 under ambient conditions (∼50% enhancement compared to the DGFC based on the Pt/C benchmark) and deliver a record voltage of 1.13 V ever reported in alcohol-feeding fuel cells. Besides the electricity profits, the DGFC concurrently generates value-added formate as a selective product of glycerol oxidization.
研究领域:
电化学
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材料科学
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能源工程
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催化
✓ 已验证
DOI
高影响因子
Drug Delivery and Translational Research
·
2023
·
IF 5.4
Ruan Hang,Shen Lina,Hou Xiaolin,Li Jiaqi,Guo Teng,Zhu Chunyun,Feng Nianping,Zhang Yongtai
Although the introduction of glycerosomes has enriched strategies for efficient transdermal drug delivery, the inclusion of cholesterol as a membrane stabilizer has limited their clinical application. The current study describes the development and optimization of a new type of glycerosome (S-glycerosome) that is formed in glycerol solution with β-sitosterol as the stabilizer. Moreover, the transdermal permeation properties of lappaconitine (LA)-loaded S-glycerosomes and peppermint oil (PO)-mediated S-glycerosomes (PO-S-glycerosomes) are evaluated, and the lipid alterations in the stratum corneum are analyzed via lipidomics. The LA-loaded S-glycerosomes prepared by the preferred formulation from the uniform design have a mean size of 145.3 ± 7.81 nm and an encapsulation efficiency of 73.14 ± 0.35%. Moreover, the addition of PO positively impacts transdermal flux, peaking at 0.4% (w/v) PO. Tracing of the fluorescent probe P4 further revealed that PO-S-glycerosomes penetrate deeper into the skin than S-glycerosomes and conventional liposomes. Additionally, treatment with PO-S-glycerosomes alters the isoform type, number, and composition of sphingolipids, glycerophospholipids, glycerolipids, and fatty acids in the stratum corneum, with the most notable effect observed for ceramides, the main component of sphingolipids. Furthermore, the transdermal administration of LA-loaded PO-S-glycerosomes improved the treatment efficacy of xylene-induced inflammation in mice without skin irritation. Collectively, these findings demonstrate the feasibility of β-sitosterol as a stabilizer in glycerosomes. Additionally, the inclusion of PO improves the transdermal permeation of S-glycerosomes, potentially by altering the stratum corneum lipids. Graphical Abstract
研究领域:
药剂学
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制药技术
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药物递送系统
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脂质科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Molecular Catalysis
·
2024
·
IF 3.9
Jia Ding,Jinghui Qin,Shengyu Zhou,Yuanhao Wu,Chao Fan,Yulong Li,Jianguo Wang
LaBO 3 ( B = Fe, Co, Ni) perovskite catalysts were prepared by the sol-gel method. The physical properties and active sites were characterized by XRD, BET, SEM, TEM, XPS, EPR, and CO 2 -TPD. The results indicated that catalysts had fine perovskite structure and high crystallinity. The as-synthesized catalysts were used for the glycerol carbonylation with CO 2 to glycerol carbonate (GC). The LaCoO 3 exhibited high conversion and selectivity of 26.3 and 72.4 % at a reaction temperature of 150 °C for 12 h under CO 2 pressure of 3 MPa in the presence of 2-cyanopyridine with DMF as the solvent. It was found that surface oxygen defects favored the glycerol conversion, while the high concentration of total weak and medium basic sites promoted the GC selectivity. The LaCoO 3 also displayed excellent reusability performance, indicating its great potential in industrial applications.
研究领域:
化学
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催化
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材料科学
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绿色化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE
·
2013
·Vol. 94
·期 8
·1614-1621
·
IF 1.759
Xiao-Li Qin,Dong-Ming Lan,Jin-Feng Zhong,Lu Liu,Yong-Hua Wang,Bo Yang
BACKGROUND T1 lipase has received considerable attention due to its thermostability. Fatty acid specificity of T1 lipase (crude and purified) was investigated, and its potential in the synthesis of acylglycerols was also evaluated . RESULTS Fatty acid specificity of T1 lipase (crude and purified) was investigated in the esterification of fatty acids (C6:0 to C18:3), suggesting that crude and purified T1 lipase had the lowest preference for C18:0 [specificity constant (1/ α ) = 0.08] followed by C18:1 (1/ α = 0.12) and showed the highest preference for C8:0 (1/ α = 1). A structural model was constructed to briefly explore interactions between the lipase and its substrate. Furthermore, crude T1 lipase-catalysed synthesis of diacylglycerols (DAGs) and monoacylglycerols (MAGs) by esterification of glycerol with C18:1 was studied for evaluating its potential in acylglycerols synthesis. The optimal conditions were glycerol/oleic acid molar ratio 5:1, the lipase concentration 9.7 U g −1 of substrates, water content 50 g kg −1 of substrates and temperature 50 °C, which yielded 42.25% DAGs, 26.34% MAGs and 9.18% triacylglycerols at 2 h . CONCLUSION DAGs and MAGs were synthesised in good yields although C18:1 (a much poorer substrate) was used. Our work demonstrates that T1 lipase, which was discovered to show 1,3-regio-selectivity, is a promising biocatalyst for lipids modification. © 2013 Society of Chemical Industry
研究领域:
生物化学
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酶工程
✓ 已验证
DOI
PubMed
高影响因子
LWT-FOOD SCIENCE AND TECHNOLOGY
·
2023
·
IF 6
Le Wang,Mingwu Zang,Xiaoyu Cheng,Shouwei Wang,Xin Zhao,Bing Zhao,Dan Li
This study aimed to explore the effects of storage on lipid profiles changes and potential candidates of lipid oxidation in dried shrimps using chemical and lipidomics analysis. Results showed that peroxide value (POV) and thiobarbituric acid-reactive substances (TBARS) significantly increased. A total of 790 lipid molecular species belonging to 7 main classes were identified, among which glycerophospholipids (GPs, 72.91%) were the most abundant, followed by glycerolipids (GLs, 13.67%) and sphingolipids (SPs, 8.10%). Phosphatidylcholine (PC), phosphatidylethanolamine (PE), triglyceride (TG) and diglyceride (DG) as dominant lipid species were susceptible to oxidization/hydrolyzation mainly because of their unsaturated structures. Using multivariate statistical analysis, 163 differential lipid molecules were screened, including 131 and 32 differentially abundant lipids (DALs) accumulating at high and low abundance levels, respectively. After storage, most of phospholipids significantly decreased, while corresponding lysophospholipids increased. Particularly, it was found that TGs and DGs with fatty acids of 18:1 and 18:2 were more likely to be downregulated. Furthermore, 18 DALs were selected as potential biomarkers of lipid oxidation in dried shrimps. This study provided insights into lipid oxidation mechanism and the changes in lipid profiles of dried shrimps during storage.
研究领域:
食品科学
·
生物学
✓ 已验证
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2018
·
IF 2.196
Ruilong Jia,Binbin Zhao,Wenjie Xue,Lei Liu,Jinxiang Dong
Formic acid-mediated deoxydehydration of glycerol has emerged as an attractive approach to produce allyl alcohol; however, separation of allyl alcohol by distillation is not a straightforward task from the mixture of allyl alcohol, formic acid, and water because of their very close boiling point. A new route to separate allyl alcohol with high purity has been developed by the precipitation, distillation, and salting-out process. Among 11 salts, NaCl, K2HPO4, and K2CO3 could easily induce the liquid–liquid phase splitting. K2CO3 exhibits the best salting-out effect in a single salt system. Meanwhile, the solubility of allyl alcohol in the organic phase could be predicted by the mass fraction of salt. The allyl alcohol purity of >99.9% could be achieved by using 35% K2CO3 + 25% K2HPO4. The results also provide valuable references to obtain high-purity allyl alcohol for all the glycerol to allyl alcohol routes, because it is indispensable to separate allyl alcohol from its aqueous solution.
研究领域:
化学工程
·
绿色化学
✓ 已验证
产品关联
DOI
高影响因子
FOOD CHEMISTRY
·
2022
·
IF 9.231
Jing Li,Youyou Yang,Chaohua Tang,Shengnan Yue,Qingyu Zhao,Fadi Li,Junmin Zhang
Intramuscular fat (IMF) content is associated with lamb flavor and largely varies between individuals of the same breed. However, studies investigating the effects of IMF variations on lipid profiles and aroma compounds are limited. Here, we performed lipidomic and volatilomic profiling of high-IMF and low-IMF Hu lambs. Triglycerides and diglycerides in the high-IMF group were significantly higher than those in the low-IMF group ( p < 0.05). Seventy-nine of 842 lipids identified were significantly different between the groups under positive and negative ion modes (variable importance in projection > 1, p < 0.05). Volatilomic analyses revealed that the aroma profiles also differed between the groups. Fifteen aroma compounds, mainly originating from lipid oxidation, could be responsible for this difference. Thus, our findings provide a comprehensive understanding of the increases in IMF content that drive consumers’ satisfaction and also provide a basis for underpinning breeding value for IMF.
研究领域:
动物科学
·
食品科学
·
生物化学
✓ 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）