GREEN CHEMISTRY
·
2020
·Vol. 22
·期 13
·4222-4230
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IF 9.48
Jiayuan Yu,Anker Degn Jensen,Lei Wang,Chunshan Li,Suojiang Zhang
Methacrolein (MAL) is an important chemical for the manufacture of methyl methacrylate and a key monomer in many polymerization reactions. In this study, L-proline was investigated as the catalyst for the aldol condensation of formaldehyde and propionaldehyde to produce MAL. The catalytic activity of the reaction system was closely related to the competition between the main reaction synthesizing MAL and the side reaction producing 2-methyl-2-pentenal, which could be modified by adjusting the operating parameters. The influences of several operating conditions, including temperature, reaction time and water content, on the catalytic performance of the system were systematically studied via a series of single-factor experiments, and the optimized reaction conditions were obtained. The mechanistic investigation via ESI-MS indicated that the reaction pathway followed the Mannich route. Experimental and theoretical kinetic analyses of the L-proline-catalyzed aldol condensation reaction were performed, and the reaction orders of the reactants were obtained by regression. The results showed that L-proline was an efficient catalyst for the production of MAL via aldol condensation under mild conditions.
研究领域:
化学工程
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有机化学
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DOI
高影响因子
APPLIED CATALYSIS A-GENERAL
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2023
·
IF 5.5
Hongxian Luo,Gang Li,Longxin Ju,Qiang Lv
Herein, an environmentally friendly and compositionally tunable proline-functional polymer was prepared by copolymerization of divinylbenzene (DVB) with L-proline functional monomer . The synthesized poly[DVB-(4-APCA) x ]s were characterized by Powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FT-IR), solid state 13 C cross-polarization/magic angle spinning NMR (solid state 13 C CP/MAS NMR), thermogravimetry-Mass (TG-MS). The combined characterization results elucidated the skeletal structure of the polymer. The proline-functional polymer was used as catalyst in the preparation of methacrolein (MAL) by liquid phase condensation of formaldehyde (FA) and propionaldehyde (PA), in which the conversion of PA is 73.3%, the selectivity of MAL is 85.6% and the yield of MAL is 62.8% under 0.1 g poly[DVB-(APCA)]s at 75 °C for 4 h when dimethyl sulfoxide (DMSO) is used as the solvent. Its catalytic performance did not degrade markedly after five cycles. Moreover, the kinetics of the condensation reaction was also studied using the isolation method.
研究领域:
化学工程
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催化化学
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DOI
高影响因子
FOOD RESEARCH INTERNATIONAL
·
2024
·
IF 7
Dongzhu Huang,Chenyi Sun,Yuhan Wu,Fangling Zheng,Qiqi Yang,Xinmeng Zhang,Qianying Dai,Xiaochun Wan,Qi Chen
This study aimed to investigate the effect of the combination of shaking and various anaerobic treatments on the aroma quality of gabaron oolong tea (GAOT) by chemical and sensory evaluation. The results showed that elevated anaerobic treatment harmed GAOT aroma, emphasizing undesirable attributes such as earthy, fatty, etc. A total of 85 volatiles were identified by gas chromatography-ion mobility spectrometry (GC-IMS), and the relationship between aroma attributes and volatiles were revealed by PLS regression projection and correlation network. Hexanal and octanal at inappropriate concentrations were main causes to the earthy attribute, while nonanal exhibited a potential masking effect against unpleasant attributes. Addition experiments and σ-τ plot analysis verified these associations. Furthermore, observing dynamic patterns of content changes of these three aldehydes in fresh leaves prior to tea thermal processing, providing references for future process optimization. These results provide a new direction for enhancing the quality of GAOT.
研究领域:
食品科学
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茶叶加工学
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化学分析
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DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2018
·
IF 6.434
Kaiyu Jiang,Caihuan Huang,Rui Jiao,Weibin Bai,Jie Zheng,Shiyi Ou
Acrolein (ACR), glyoxal (GO), methylglyoxal (MGO), hydroxymethylfurfural (HMF), and malondialdehyde (MDA) are toxic contaminants for humans. This work aimed to investigate whether intake of proteins can mitigate their toxicity. Simulated gastrointestinal digestion of proteins from pork, chicken, milk powder and soy protein isolate eliminated amount of ACR, GO, MGO, HMF, and MDA. Among six amino acids, cysteine showed highest capacity for elimination of these toxic compounds through the formation of adducts; it reached the highest elimination capacity for GO, MGO, ACR, MDA, and HMF in 40 min at pH 2.0, and 20 min at pH 7.0. The formed adducts between cysteine and GO, MGO, or ACR showed much lower toxicity against Caco-2 cells. Incubation of the cells with 8 mM GO and MGO for 48 h decreased the cell viability to 16.1%, 16.9% respectively; while incubation of the same concentration of their adducts still kept the cell viability at 82.2% and 81.6% respectively. Cysteine showed much higher detoxifying capacity for ACR than GO and MGO, which can lower the toxicity of ACR toward Caco-2 cells by 80 times.
研究领域:
食品科学
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毒理学
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细胞生物学
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DOI
PubMed
高影响因子
ACS Applied Polymer Materials
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2023
·
IF 5
Ke Li,Xiaoyi Sun,Hua Yin,Kun Yang,Pei Dai,Ling Han,Longgui Zhang,Riwei Xu
Preparing biobased high-performance thermosetting resins is one of the most important factors for sustainable development. In this work, two kinds of phthalonitrile resins containing spirocycle acetal structures were synthesized from pentaerythritol and renewable vanillin and isovanillin by an efficient two-step process. The structures of vanillin- and isovanillin-based phthalonitrile (VPN and IVPN) monomers were characterized by Fourier transform infrared (FTIR), NMR, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, and elemental analysis. The curing behaviors of these monomers were studied by differential scanning calorimetry and FTIR. The thermal stability and dynamic mechanical properties of the cured resins were investigated by thermogravimetric analysis and dynamic mechanical thermal analysis. The processing properties were studied by a rheological analysis. Compared with traditional petroleum-based phthalonitrile resins such as bisphenol A and bisphenol, cured VPN and IVPN resins exhibited good thermal stability and thermomechanical properties, high glass transition temperature (Tg), and excellent processability.
研究领域:
材料科学
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有机化学
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DOI
高影响因子
JOURNAL OF FOOD COMPOSITION AND ANALYSIS
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2023
·
IF 4.3
Jianhua Huang,Hongying He,Lijun Wang,Zhihua Song,Xingguo Wang,Xiaosan Wang
It is necessary to study the formation of aldehydes in oil at high temperature. Different from the traditional heating mechanism, microwave heating is widely used, and its effect on aldehydes is also noteworthy. In this paper, we mainly investigated the changes of volatile and non-volatile aldehydes in high oleic sunflower oil (HOSO) under various microwave powers and treatment times. The findings indicate that the oil heated by microwave produces more than 20 volatile aldehydes and 4 non-volatile aldehydes (glycerol ester core aldehydes, GCAs). Hexanal , nonanal , (E)− 2-heptenal, (E)− 2-decenal, and (E,E)− 2,4-decadienal were higher in volatile aldehydes content, while GCAs gradually grew as microwave powers and treatment times increased. The GCAs concentration can increase to 0.72 ± 0.07 mg/kg when the oil is treated at 700 W for 30 min, with the content of four GCAs (8-oxo, 9-oxo, 10-oxo-8, 11-oxo-9) being 0.06 ± 0.01, 0.51 ± 0.06, 0.10 ± 0.00, 0.05 ± 0.00 mg/kg. In particular, GCAs (9-oxo) represented the majority of the overall amount of GCAs during the entire procedure.
研究领域:
食品科学
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化学工程
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DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
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2023
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IF 6.1
Wei Jiang,Xiaoyuan Wang,YunJiao Ma,Ming Du,Chao Wu,Xianbing Xu
Maillard flavor compounds, such as 2,3,5-trimethylpyrazine, have been frequently identified in thermally processed food products, such as popcorn and peanuts. However, the origin of the carbon atoms in 2,3,5-trimethylpyrazine has not been clearly elucidated. Herein, a model reaction showed that precursor methylglyoxal and intermediates glyoxal and formaldehyde contributed to the formation of 2,3,5-trimethylpyrazine via a conversion reaction between methylglyoxal and glyoxal. In addition, carbon module labeling technology and model response validation experiments indicated that this transformation reaction between methylglyoxal and glyoxal brought formaldehyde into the methyl group carbon atoms of the 2,3,5-trimethylpyrazine ring. The proposed novel route provides a new perspective for approaches to control the formation of flavor compounds, such as 2,3,5-trimethylpyrazine.
研究领域:
食品科学
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有机化学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE
·
2018
·Vol. 98
·期 12
·4733-4741
·
IF 2.379
Chunfeng Liu,Qi Li,Chengtuo Niu,Feiyun Zheng,Yun Zhao
BACKGROUND Acetaldehyde is an important flavor component in beer which is possibly carcinogenic to humans. Owing to the limitations of present detection methods, only free-state acetaldehyde in beers has been focused on, while acetal in beers has hardly been reported so far. RESULTS A sensitive headspace gas chromatography method was developed for the determination of diethylacetal and acetaldehyde in beer. The column DB-23 was chosen with a total run time of 22.5 min. The optimal addition amount of NaCl, equilibrium temperature and equilibrium time were 2.0 g, 70 °C and 30 min respectively. For both diethylacetal and acetaldehyde analyses, the limit of detection was 0.005 mg L −1 with relative standard deviation < 5.5%. The recoveries of acetaldehyde and diethylacetal were 95–110 and 95–115% respectively. The diethylacetal and acetaldehyde average contents in 24 beer products were 11.83 and 4.36 mg L −1 respectively. The Pearson correlation coefficient between diethylacetal and acetaldehyde was the highest (0.963). Both diethylacetal and acetaldehyde contents increased to a peak value after fermentation for 3 days and then decreased to a lower value. During both normal and forced aging storage, the diethylacetal content decreased and the acetaldehyde content increased gradually over time. When beers were forced aged for 4 days, the increased ratio of acetaldehyde could be above 40.00%. CONCLUSION The newly established method can be used to assess acetaldehyde level and flavor quality in beer more scientifically. © 2018 Society of Chemical Industry
研究领域:
食品科学
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分析化学
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产品关联
DOI
PubMed
高影响因子
Frontiers in Bioengineering and Biotechnology
·
2023
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IF 5.7
Huang Lizhen,Bian Zelun,Li Dalin,Cheng Xin,Luo Xiaolin,Shuai Li,Liu Jing
Biobased furfural is a sustainable alternative to petrochemical intermediates for bulk chemicals and fuel production. However, existing methods for the conversion of xylose or lignocelluloses in mono-/bi-phasic systems to furfural involve non-selective sugar isolation or lignin condensation, limiting the valorisation of lignocelluloses. Herein, we used diformylxylose (DFX), a xylose derivative that is formed during the lignocellulosic fractionation process with formaldehyde protection, as a substitute for xylose to produce furfural in biphasic systems. Under kinetically optimized conditions, over 76 mol% of DFX could be converted to furfural in water-methyl isobutyl ketone system at a high reaction temperature with a short reaction time. Finally, isolation of xylan in eucalyptus wood as DFX with formaldehyde protection followed by converting DFX in a biphasic system gave a final furfural yield of 52 mol% (on the basis of xylan in wood), which was more than two times of that without formaldehyde. Combined with the value-added utilization of formaldehyde-protected lignin, this study would enable the full and efficient utilization of lignocellulosic biomass components and further improve the economics of the formaldehyde protection fractionation process.
研究领域:
化学工程
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可持续化学
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生物化学工程
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DOI
PubMed
高影响因子
IUBMB LIFE
·
2019
·Vol. 71
·期 7
·1014-1020
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IF 3.051
Yanbin Su,Chengyu Sun,Yan Chen,Shichang Liu,Ning Jing,Shuxin Li
The aim of this study was to explore how the toxic trans -crotonaldehyde (TCA) in mitochondria or aldehyde dehydrogenase (ALDH) at different pHs was intercepted by oxyresveratrol (Oxy-Res) contributing to anticancer. Ultraviolet–visible (UV–vis) spectroscopy and Raman spectroscopy were employed. UV–vis spectra showed that the Oxy-Res red shifted the peak of the toxic TCA from 316 nm to 325 nm, while the peaks of the Oxy-Res shifted from 329 nm with 290 nm and 300 nm to 325 nm with 303 nm. In the mitochondria, the Oxy-Res blue shifted the peaks of the toxic TCA from 325 nm with 303 nm to 321 nm with 301 nm. Raman spectra revealed that the Oxy-Res caused shifting of the CHO of the toxic TCA from 1,689 cm −1 to 1,671 cm −1 with band decline. The CC of the toxic TCA at 1641 cm −1 was split into 1,639 cm −1 and 1,642 cm −1 with band decline. The bands of the Oxy-Res at 1634 cm −1 , 1,617 cm −1 , and 1,595 cm −1 disappeared. In the mitochondria, the CC of the toxic TCA at 1641 cm −1 splitting disappeared. In ALDH, with the decrease of pH from 7.8 to 6.5, the CHO of the toxic TCA did not red shift from 1,689 cm −1 to 1,674 cm −1 up to pH 6.5. There was no change in the CC of the toxic TCA at 1640 cm −1 in ALDH at different pHs. The conclusion of the study was that the CHO of the toxic TCA was intercepted by the Oxy-Res under the action of ALDH in the mitochondria, particularly at pH 7.8. © 2019 IUBMB Life, 2019
研究领域:
生物化学
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医学
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药理学
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DOI
PubMed
高影响因子
APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY
·
2013
·Vol. 171
·期 7
·1559-1567
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IF 1.893
Wang Na,Zhang Wei,Zhou Long-Hua,Deng Qing-Feng,Xie Zong-Bo,Yu Xiao-Qi
A facile tandem route to α,β-unsaturated aldehydes was developed by combining the two catalytic activities of the same enzyme in a one-pot strategy for the aldol reaction and in situ generation of acetaldehyde. Lipase from Mucor miehei was found to have conventional and promiscuous catalytic activities for the hydrolysis of vinyl acetate and aldol condensation with in situ formed acetaldehyde. The first reaction continuously provided material for the second reaction, which effectively reduced the volatilization loss, oxidation, and polymerization of acetaldehyde, as well as avoided a negative effect on the enzyme of excessive amounts of acetaldehyde. After optimizing the process, several substrates participated in the reaction and provided the target products in moderate to high yields using this single lipase-catalyzed one-pot biotransformation.
研究领域:
生物化学
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酶工程
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产品关联
DOI
PubMed
高影响因子
Catalysts
·
2021
·Vol. 11
·期 3
·394
·
IF 4.146
Baohe Wang,Honggang Dong,Liang Lu,Hongxia Liu,Zhaobang Zhang,Jing Zhu
A series of KxH1.1-xCu0.2Cs1(NH4)1.5PVMo11O40(KxCuCsNH4PVA) catalysts with differentxvalues were synthesized to catalyze the selective oxidation of methacrolein (MAL) to methacrylic acid (MAA). The effects of potassium (K) ions on both the structure and catalytic activity were studied in detail. The optimum K0.6CuCsNH4PVA exhibited a large surface area, more acid sites, and abundant active species (V4+/VO2+) in the secondary structure of the Keggin structure, consequently offering good catalytic performance. Furthermore, K ions increased the MAA selectivity at the expense of carbon monoxide and carbon dioxide (together defined as COX). Additionally, several process parameters for MAL oxidation were evaluated in the processing experiments. The effects of aldehyde impurities (formaldehyde and propanal) on the catalytic performance were investigated. Possible detrimental effects (catalyst poisoning and structural damage) of aldehyde impurities were excluded. A light decrease in MAL conversion could be attributed to the competitive adsorption of aldehyde impurities and MAL on the catalyst. Hopefully, this work contributes to the design of stable and feasible catalysts for the industrial production of MAA.Keywords:potassium;methacrolein;formaldehyde;propanal;selective oxidation;methacrylic acid;catalytic performance
研究领域:
化学工程
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催化材料科学
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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）