Molecular Catalysis
·
2024
·
IF 3.9
Hui Cao,Yu Liu,Yanqiu Li,Yingxiong Wang,Yan Qiao
The α-hydroxyketones and 1,2-diols are versatile building blocks for the preparation of many natural and synthetic bioactive compounds. In this study, N-heterocyclic carbon (NHC) promoted coupling of several aldehydes with formaldehyde enabled the synthesis of 1,2-diols in moderate to high yields. The highly selective conversion of several aldehydes and formaldehyde into 1,2-diols and α-hydroxyketones was achieved in a one-pot two-step process via [BHMIm][OAc] as a key intermediate. In the first step, formaldehyde was quantitatively converted to [BHMIm][OAc] through the carbene addition. In the second step, 1,2-diol was produced through the intermediate-promoted aldol reaction. The results showed that benzaldehyde was capable to react with [BHMIm][OAc] efficiently, with a 54.1% yield of 1,2-diol after the 3-hour reaction at 85 °C. Among the tested benzaldehyde derivatives, the 4-nitrobenzaldehyde showed the highest yield of 1,2-diol (73.3%) under the optimized reaction conditions. Incorporation of an electron rich group on benzaldehyde promoted carbene regeneration. With 4-methoxybenzaldehyde as the substrate, the yield of α-hydroxyketone reached a maximum of 30.6%. Additionally, dihydroxyacetone derivatives were detected in the system. In situ NMR technique confirmed that it was generated from the further reaction of the carbene/1,2-diol complex with another aldehyde. Based on the results of NMR spectroscopy and mass spectrometry, a possible reaction pathway was also proposed.
研究领域:
有机化学
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合成化学
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DOI
高影响因子
Bioresources and Bioprocessing
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2018
·Vol. 5
·期 1
·1-12
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IF 0
Zheng Liandan,Lin Jinping,Zhang Baoqi,Kuang Yuyao,Wei Dongzhi
A NAD(P)H-dependent enoate reductase (OYE2p) from Saccharomyces cerevisiae YJM1341 was discovered by genome data mining for asymmetric reduction of (E/Z)-citral to (R)-citronellal with high enantioselectivity.This enzyme was heterologously expressed in E. coli and characterized for its biocatalytic properties. OYE2p was identified with reduction activities toward a diverse range of ɑ,β-unsaturated compounds bearing conjugated aldehyde, ketone, imide, carboxylic acid and ester.OYE2p showed the highest specific activity at 40 °C and a pH optimum at 7.0–8.0. The stability of OYE2p was rather pH-independent, and the half-life time values of the enzyme at pH 6.0–8.0 were more than 257 h. With regard to the reduction of (E)-citral and (Z)-citral, OYE2p exhibited different selectivity patterns. (E)-citral was exclusively reduced to (R)-citronellal by OYE2p in ≥ 99% ee, which was independent on pH. OYE2p produced both enantiomers of citronellal from (Z)-citral, but showed (R)-citronellal formation tendency, and the ee value of (R)-citronellal was affected by pH in the reaction system. Accordingly, the ee values for (R)-citronellal formation increased with the increasing levels of E-isomer in the (E/Z)-citral mixture as well as the increase of pH. Under the reaction conditions (30 °C and pH 8.6), using purified OYE2p as catalyst, 200 mM (E/Z)-citral (an approximately 10:9 mixture of geometric E-isomer and Z-isomer) was efficiently converted to (R)-citronellal with 88.8% ee and 87.2% yield.All these positive features demonstrate high potential of OYE2p for practical synthesis of (R)-citronellal and in asymmetric reduction of activated alkenes.
研究领域:
生物化学
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酶工程
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合成生物学
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DOI
BIORESOURCE TECHNOLOGY
·
2022
·
IF 11.889
Shanta Dutta,Qiaozhi Zhang,Yang Cao,Chunfei Wu,Konstantinos Moustakas,Shicheng Zhang,Ka-Hing Wong,Daniel C.W. Tsang
Lignocellulosic paper waste constitutes a major waste stream globally, which should be valorised for chemical production. However, paper properties ( e.g. , feedstock composition, cellulosic crystallinity, and thermal stability/degradability) vary with raw materials and pulping processes. This study investigated levulinic acid (LA), hydroxymethylfurfural (HMF), and furfural production by H 2 SO 4 and FeCl 3 catalysed conversion of nine types of paper wastes in a green solvent system (1:1 γ‐valerolactone/water). At 160–180 °C for 1–20 min, ∼23–27 wt% LA yield was achieved from sanitary papers, tracing/parchment paper, and paper food box mainly containing crystalline cellulose, while a lower LA yield (∼10–20 wt%) was obtained from other paper wastes with high contents of ash and lignin. A higher selectivity towards HMF (∼12 mol%) was achieved in the presence of FeCl 3 . A furfural yield of ∼ 4–7.5 wt% was also obtained from the hemicellulose content. This study elucidates crucial factors and desirable characteristics of paper waste for catalytic valorisation.
研究领域:
化学工程
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环境科学
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生物质能
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DOI
PubMed
高影响因子
FLUID PHASE EQUILIBRIA
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2016
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IF 1.846
Jianguang Qi,Yufeng Hu,Yue Gao,Weiting Ma,Shuqin Mo,Zhenyu Yang,Xianming Zhang,Liuyi Yin
Extraction was a key step in industrial process of trioxane . NaOH was utilized in industrial production of trioxane to maintain appropriate pH to prevent trioxane decomposition. Here efforts were made to investigate the salt effects that can produce an alkaline medium to prevent trioxane decomposition and, simultaneously, can induce salting-out effect to considerably increase the efficiency of extraction of trioxane from aqueous formaldehyde solutions. The salt considered included K 3 PO 4 , Na 3 PO 4 , sodium tartrate (Na 2 C 4 H 4 O 6 ) and sodium citrate (Na 3 C 6 H 5 O 7 ). The decomposition measurements were made for the (trioxane + formaldehyde + salt + H 2 O) solutions at 323.15 K for 96 h. No trioxane decomposition was detectable over the whole experimental time. Extraction measurements were made using each of the selected salts or NaOH as accelerant salt and benzene, dichlorobenzene or dimethylbenzene as extraction solvent . The results showed that both the extraction efficiency and the distribution coefficient were considerably increased and that such effects followed the order Na 3 PO 4 > K 3 PO 4 > Na 3 C 6 H 5 O 7 > Na 2 C 4 H 4 O 6 > NaOH. The results also showed that the effects of these salts on the water content in the organic phase and on the organic phase residual in the water phase were generally similar to or even more favorable than those of NaOH. The liquid−liquid phase equilibrium data were measured for the (trioxane + formaldehyde + K 3 PO 4 + H 2 O + benzene) solutions at (313.15, 323.15 and 333.15) K and were found to be well described by the Othmer−Toblas and the Hand equations.
研究领域:
化学工程
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工业化学
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DOI
高影响因子
JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY
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2020
·
IF 3.255
Jingwen Hu,Shi-En Chen,Shuyun Zhu,Wenhui Jia,Jing Sun,Xian-En Zhao,Huwei Liu
In this work, a new series of chemical isotope labeling reagents, levofloxacin-hydrazide-based mass tags (LHMTs) named as LHMT359/360/361/362/363/364/365/366/373/375/376/378/379/381 were first designed and synthesized for the high-throughput analysis of potential biomarkers containing hexanal and heptanal of lung cancer. We exploited a new core structure of levofloxacin-d3, which significantly enhanced the multiplexing capability. Among them, LHMT359 was used for labeling standard compounds as internal standards for quantification. Using LHMT373-heptanal as dummy template, dummy magnetic molecularly imprinted polymers (DMMIPs) were prepared for magnetic dispersive solid-phase extraction after derivatization procedure. Other 12 LHMTs were established for high-throughput labeling hexanal and heptanal in human serum samples. The presynthesized DMMIPs can selectively extract LHMTs-derivatives of hexanal and heptanal from equally mixed derivatization solutions. The enriched derivatives of hexanal and heptanal were quantified by ultrahigh-performance liquid chromatography tandem mass spectrometry (UHPLC–MS/MS). A single UHPLC–MS/MS run enabled simultaneously quantifying hexanal and heptanal from 12 serum samples only within 2 min. The limits of detection were all 0.5 pM for hexanal and heptanal. The accuracies from human serum samples ranged from −10.2% to +11.0% with the intra- and interday precisions less than 11.3%. Meanwhile, this method was successfully applied for the analysis of hexanal and heptanal in serum samples from healthy people and lung cancer patients. The results show that this method has the significant advantages of high sensitivity, accuracy, selectivity, and analysis-throughput. The method application indicates that the developed method is promising in the screening of suspected lung cancer patients.
研究领域:
分析化学
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医学
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生物标志物研究
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DOI
PubMed
高影响因子
Processes
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2022
·Vol. 10
·期 7
·1302
·
IF 3.352
Hailun Ren,Weihong Li
3-hydroxybutyraldehyde (3-HBA) is mainly employed to synthesize 1,3-BDO (1,3-butanediol), which is one of the most important components in cosmetics moisturizers. In this study, a series of composite oxide catalysts were prepared by bringing alkaline earth metal Ca and rare earth metal La to the composite oxide MgO/Al2O3, which were made through the co-precipitation method. These catalysts were applied in the synthesis of 3-HBA through acetaldehyde (AcH) condensation. The structure, texture, and acidic properties of these catalysts were characterized using various characterization methods, and the effects of catalyst composition, reaction temperature, reaction pressure, and residence time on the conversion of AcH were investigated as well. The results showed that the introduction of Ca and La weakened the acidic property and enhanced the basic property, which favored the AcH condensation to synthesize 3-HBA. At a temperature of 20 °C, pressure of 200 kPa, and residence time of 70 min, 0.5%La-2.3%Ca-2MgO/Al2O3exhibited a better catalytic activity, and the conversion of AcH reached 95.89%. The selectivity and yield of 3-HBA were 92.08% and 88.30%, respectively. The stability test indicated that the high AcH conversion could be maintained for 5 h.Keywords:composite oxides;acetaldehyde;condensation catalyst;3-hydroxybutyraldehyde
研究领域:
催化化学
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绿色化学
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DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
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2018
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IF 3.412
Qianzhu Zhao,Juanying Ou,Caihuan Huang,Ruixia Qiu,Yong Wang,Fu Liu,Jie Zheng,Shiyi Ou
The absorption of a 5-hydroxymethylfurfural (HMF)–cysteine adduct, 1-dicysteinethioacetal–5-hydroxymethylfurfural (DCH), and its effect on antioxidant activity and gut microbiota were investigated. Results indicated that DCH is more easily absorbed in rats than HMF. Serum DCH concentrations were 15–38-fold of HMF concentrations from 30 to 180 min after intragastrical administration at the level of 100 mg/kg of body weight, and 2.7–4.5% of absorbed DCH was converted to HMF. The malondialdehyde content in the plasma, heart, liver, and kidneys significantly increased after drug (100 mg/kg of bw) administration for 1 week, suggesting that HMF and DCH were oxidative-stress-inducing agents, instead of antioxidant agents, in rats. HMF and DCH also modulated gut microbiota. HMF promoted the growth of Lactobacillus, Tyzzerella, Enterobacter, and Streptococcus. DCH increased the ratio of Firmicutes/Bacteroidetes and promoted the growth of Akkermansia, Shigella, and Escherichia while inhibiting the growth of Lactobacillus.
研究领域:
营养学
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药理学
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微生物学
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DOI
PubMed
高影响因子
ACS Applied Polymer Materials
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2024
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IF 4.4
Yehan Tao,Siying Zhou,Qi Luo,Fei Song,Xiaoyu Gong,Zhicheng Wang,Haisong Wang,Changzhi Li
Traditional phenol-formaldehyde resin involves the use of petrochemical-based phenol and formaldehyde as feedstocks, raising environmental and health concerns. Herein, renewable biobased substances, i.e., lignin and furfural, were employed to partially replace petroleum-based phenol and formaldehyde for developing greener adhesives by batch copolymerization method. The substitution rates of phenol by acetonitrile-extracted lignin and formaldehyde by furfural can reach 80 and 15%, respectively. The application of these greener raw materials can effectively decrease the emission of toxic content, increasing the viscosity and thermal stability without any sacrifice in the binding performance. The resin with 40% phenol substitution rate and 15% formaldehyde substitution rate displayed superior trade-off between bonding strength (a wet tensile strength of 1.68 MPa) and free formaldehyde content (0.21%) among all biobased resins, much superior to those of commercial adhesive (0.7 MPa and 5%) and those prepared with industrial lignin (0.66 MPa and 0.38%). By using two major biomass-derived feedstocks, this work provides a sustainable strategy to develop a green adhesive featuring superior adhesive properties, enhanced environmental compatibility, and improved thermal stability that shows a broader application potential in the adhesive field.
研究领域:
材料科学
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环境科学
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DOI
高影响因子
Journal of Materials Chemistry A
·
2025
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IF 9.5
Jianghua Zhang,Zuzeng Qin,Xuan Luo,Tongming Su,Xinling Xie,Hongbing Ji
The demand for natural benzaldehyde in fragrances and pharmaceuticals exceeds its supply because of consumer habits and stringent regulations. Sustainable development necessitates using eco-friendly methods for synthesizing organic compounds. This study investigates the selective photocatalytic oxidation of cinnamaldehyde to benzaldehyde using oxygen. Dual-functional xBi0/BiVO4 photocatalysts were prepared in situ by tuning the Bi/V molar ratio. xBi0/BiVO4 retained the photosensitizer properties of BiVO4, while Bi deposition on BiVO4 enhanced the generation of photogenerated electrons and the adsorption capacity for oxygen and cinnamaldehyde. The catalysts rapidly converted adsorbed oxygen into singlet oxygen, which contributed to the selective oxidation of cinnamaldehyde, achieving a benzaldehyde selectivity of 47–59%. Photogenerated electrons facilitated the formation of superoxide radicals, improving benzaldehyde selectivity and counteracting deactivation for sustained xBi0/BiVO4 activity. In this study, we synthesized an efficient and durable photocatalyst for oxidizing CC bonds in α,β-unsaturated aldehydes, addressing limitations of existing photocatalytic processes.
研究领域:
化学工程
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材料科学
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产品关联
DOI
高影响因子
PROCESS BIOCHEMISTRY
·
2024
·
IF 3.7
Shaoyang Zhang,Guorong Zhu,Zhixiang Pan,Yi Wei,Zuoming Nie,Qing Sheng,Zhongyi Yang
L-threo-methylsulonylphenylserine (L-threo-MSPS) is a crucial intermediate in florphenicol and thiamphenicol synthesis. L-threo-MSPS can be synthesized from L-threonine and p-methylsulfonylbenzaldehyde (p-MSBA) chiral selectively under the catalyse of L-threonine transaldolase . However, the byproduct acetaldehyde formed during the reaction process severely hinders the biosynthesis of high-quality L-threo-MSPS. The accumulated acetaldehyde reacts with L-thero-MSPS and L-threonine to form N-derivatives, and the activity of L-threonine transaldolase decreases to 14.10% even when the concentration of acetaldehyde is as low as 0.5 g/L. The acetaldehyde could be removed by aeration, and the removal efficiency is closely related to the aeration conditions, which was described by the volumetric oxygen transfer coefficient k L a in this paper. Regular aeration through pipes cannot provide enough aeration efficiency, and filters or sintered rods were used to increase the k L a value during the reaction. The residual concentration of acetaldehyde depended on the balance between the formation and removal speed of acetaldehyde. When the optimal enzyme concentration was applied and the k L a value of 5.5 min -1 , the L-threo-MSPS concentration reached 293.28 mM in a 1-L reaction, and the highest conversion reached 90.03%. The need of coenzyme NAD + was cut off in this method, and only one enzyme was applied. Consequently, the reaction was simpler and easier to control.
研究领域:
生物化学
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制药工程
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DOI
高影响因子
METABOLIC ENGINEERING
·
2025
·
IF 6.8
Shan Yuan,Chao Xu,Miaomiao Jin,Xinglin Jiang,Wei Liu,Mo Xian,Ping Jin
Aldehydes are ubiquitous metabolites in living cells. As reactive electrophiles, they have the capacity to form adducts with cellular protein thiols and amines, leading to potential toxicity. Dynamic regulation has proven to be an effective strategy for addressing the accumulation of toxic metabolites. However, there are limited reports on applying dynamic control specifically to mitigate aldehyde accumulation. In this study, the cinnamaldehyde accumulation in the biosynthesis of cinnamylamine was used as a model to evaluate a two-way dynamic regulation strategy. First, we utilized whole-genome transcript arrays to identify the cinnamaldehyde-responsive promoters: the upregulated promoter P 4 and the downregulated promoter P d . They were then employed as biosensors to dynamically regulate the synthesis and consumption of cinnamaldehyde, mitigating its toxic effects on the host. This strategy successfully reduced cinnamaldehyde accumulation by 50% and increased the production of cinnamylamine by 2.9 times. This study demonstrated a cinnamaldehyde-induced autoregulatory system that facilitated the conversion of cinnamic acid into cinnamylamine without the need for costly external inducers, presenting a promising and economically viable approach. The strategy also serves as a reference for alleviating the inhibitory effects of other toxic aldehydes on microorganisms. Additionally, the biosensors (P d and P 4 ) can respond to a range of aldehyde compounds, offering a rapid and sensitive method for detecting toxic aldehydes in both environmental samples and microorganisms, thus provide a valuable tool for screening strains enhanced aldehyde yield.
研究领域:
合成生物学
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代谢工程
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF FOOD COMPOSITION AND ANALYSIS
·
2025
·
IF 4.6
Wei Dai,Wenjun Tan,Xuepeng Chen,Jilei Wang,Yougui Yu,Qing Zheng
This study investigates the interconversion between acetaldehyde and its acetal derivatives during the aging process of Baijiu. Acetaldehyde imparts a pungent aroma, while acetal contributes soft fruity and sweet notes to Baijiu. The dynamic equilibrium between these two compounds, mediated by a reversible reaction, significantly influences the aromatic balance and overall flavor harmony of the liquor. By analyzing aging data from Baijiu samples of different alcohol contents (62°, 52°, and 38° ABV) and aromatic types ( Nong , Jiang , Feng , Jian ), we calculated the apparent equilibrium constant (K) and developed a model predicting the simplified equilibrium constant as a function of alcohol content. Results revealed that reduced alcohol content shifts the equilibrium toward acetaldehyde formation, diminishing acetal-derived aromas. This study pioneers a thermodynamic quantitative model for acetaldehyde-acetal interconversion in Baijiu, elucidates the regulatory role of alcohol content in reaction equilibrium through solvent effects. These findings contribute significantly to the scientific understanding of Baijiu aging and offer practical solutions for flavor optimization in Baijiu production, particularly for low-alcohol Baijiu.
研究领域:
食品化学
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风味科学
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物理化学
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热力学
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酿造技术
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）