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Theaflavins ameliorate insulin resistance and anxiety-like behavior induced by propionate combined with high-fat diet
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作者 Huijuan Bai Qian Yang +7 位作者 Xiang Zuo Qian Yu Qili Zhao Yifei Tian Yixin Xu Jiawei Du Xin Zhao Xizeng Feng 《Food Science and Human Wellness》 2025年第10期3894-3907,共14页
Insulin resistance is a key pathological process in the development of type 2 diabetes,which can also lead to depression,anxiety and other symptoms.With the accelerated pace of life,food with high-energy and additives... Insulin resistance is a key pathological process in the development of type 2 diabetes,which can also lead to depression,anxiety and other symptoms.With the accelerated pace of life,food with high-energy and additives is becoming more and more common in people's diet.Propionate is a naturally existing short-chain fatty acid salt widely used as a food preservative,but studies have found that low concentrations of propionate can induce insulin resistance.Theaflavins(TFs)are characteristic components of black tea,which have hypoglycemic and lipid-lowering effects.In the present study,propionate combined with high-fat diet was used to induce insulin resistance in mice and treated them with TFs.The results showed that propionate could aggravate insulin resistance and anxiety induced by high-fat diet in mice.TFs alleviated insulin resistance and anxiety induced by propionate combined with high-fat diet by improving the disorder of metabolic gene expression and inflammation in the adipose and liver tissue,as well as neuroinflammation in the brain.Our study suggests that the food additive propionate combined with a high-fat diet may be harmful to organismal health.As a natural drug,TFs have the potential to alleviate insulin resistance induced by propionate combined with high-fat diet. 展开更多
关键词 THEAFLAVINS PROPIONATE Insulin resistance Anxiety-like behavior
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2-(3-羧甲基-4-苯硫基苯基)丙酸的制备 被引量:1
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作者 陈文华 张宏 《中国医药工业杂志》 CAS CSCD 北大核心 2014年第1期17-18,共2页
2-(3-羧甲基-4-苯硫基苯基)丙酸(1)是消炎镇痛药扎托洛芬(zaltoprofen)的关键中间体[1]。文献以5-丙酰基-2-苯硫基苯乙酸甲酯(2)为原料,在碘和氧化亚铜复合催化下,与原甲酸三甲酯经碘代缩酮、重排、水解一锅反应制得1,总收率为72%[1],... 2-(3-羧甲基-4-苯硫基苯基)丙酸(1)是消炎镇痛药扎托洛芬(zaltoprofen)的关键中间体[1]。文献以5-丙酰基-2-苯硫基苯乙酸甲酯(2)为原料,在碘和氧化亚铜复合催化下,与原甲酸三甲酯经碘代缩酮、重排、水解一锅反应制得1,总收率为72%[1],方法中碘成本较高,不宜在工业上采用。 展开更多
关键词 2-(3-carboxymethyl-4-phenylthiophenyl)propionic acid ZALTOPROFEN INTERMEDIATE SYNTHESIS
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Vapor-Liquid Equilibrium Data of Carbon Dioxide+Methyl Propionate and Carbon Dioxide+Propyl Propionate Systems
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作者 徐伟 谢传欣 +1 位作者 李洪玲 田宜灵 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第3期317-324,I0002,共9页
High-pressure vapor-liquid equilibrium data for the binary systems of methyl propionate+carbon dioxide and propyl propionate+carbon dioxide were measured at pressure from 1.00 MPa to 12.00 MPa and temperature in the... High-pressure vapor-liquid equilibrium data for the binary systems of methyl propionate+carbon dioxide and propyl propionate+carbon dioxide were measured at pressure from 1.00 MPa to 12.00 MPa and temperature in the range from 313 K to 373 K. Experimental results were correlated with the Peng-Robinson equation of state with the two-parameter van der Waals mixing rule. At the same time, the Henry's coefficient, partial molar enthalpy change and partial molar entropy change of CO2 during dissolution at different temperature were also calculated. 展开更多
关键词 Carbon dioxide Methyl propionate Propyl propionate Vapor-liquid equilibrium data Henry's coefficient
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Catalytic Synthesis of Geranyl Propionate
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作者 唐晓红 李保军 +1 位作者 李成未 林钰 《Agricultural Science & Technology》 CAS 2012年第2期251-254,283,共5页
[Objective] The aim was to explore the optimal conditions for the catalytic synthesis of geranyl propionate. [Method] The synthesis of mesoporous molecular sieves Al-MCM-41 was carried out in an open-vessel. The mesop... [Objective] The aim was to explore the optimal conditions for the catalytic synthesis of geranyl propionate. [Method] The synthesis of mesoporous molecular sieves Al-MCM-41 was carried out in an open-vessel. The mesoporous structure of as-synthesized Al-MCM-41 was characterized by X-ray diffraction (XRD) pattern, Fourier transform infrared (FT-IR) spectrum, NH3-Temperature Programmed Desorption (TPD), and N2 adsorption-desorption isotherms. The catalytic performances of Al-MCM-41 for the synthesis of geranyl propionate (GP) with geraniol and propionic acid as reagents also were investigated. [Result] The as-synthesized Al-MCM-41 possesses typical hexagonal mesoporous structure with high long-range order and crystalline degree. Based on the systematic investigation of reaction time, temperature, amount ratio of reagents and regeneration of catalyst, the optimum reaction conditions were obtained with molar ratio of geraniol to propionic acid of 1.0∶1.5, reaction temperature of 120 ℃ and reaction time of 8 h. The high GP selectivity of 70.01% with geraniol conversion of 40.01% was achieved under above optimum conditions. The catalyst inactivation can be observed after five catalytic cycles. The regeneration of inactivated catalyst with high activity and selectivity can be achieved by calcination treatment to remove the carbon deposition, which covers the acid site of catalyst. [Conclusion] The optimal conditions for the synthesis of geranyl propionate were obtained. 展开更多
关键词 Mesoporous molecular sieves CATALYST Geranyl propionate
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Anti-inflammatory properties of the short-chain fatty acids acetate and propionate:A study with relevance to inflammatory bowel disease 被引量:93
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作者 Sofia Tedelind Fredrik Westberg +1 位作者 Martin Kjerrulf Alexander Vidal 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第20期2826-2832,共7页
AIM: To compare the anti-inflammatory properties of butyrate with two other SCFAs, namely acetate and propionate, which have less well-documented effects on inflammation. METHODS: The effect of SCFAs on cytokine rel... AIM: To compare the anti-inflammatory properties of butyrate with two other SCFAs, namely acetate and propionate, which have less well-documented effects on inflammation. METHODS: The effect of SCFAs on cytokine release from human neutrophils was studied with EHSA. SCFA- dependent modulation of NF-κB reporter activity was assessed in the human colon adenocarcinoma cell line, Colo320DM. Finally, the effect of SCFAs on gene expression and cytokine release, measured with RT-PCR and ELISA, respectively, was studied in mouse colon organ cultures established from colitic mice. RESULTS: Acetate, propionate and butyrate at 30 mmol/L decreased LPS-stimulated TNFα release from neutrophils, without affecting IL-8 protein release. All SCFAs dose dependently inhibited NF-κB reporter activity in Colo320DM cells. Propionate dose-dependently suppressed IL-6 mRNA and protein release from colon organ cultures and comparative studies revealed that propionate and butyrate at 30 mmol/L caused a strong inhibition of immune-related gene expression, whereas acetate was less effective. A similar inhibition was achieved with the proteasome inhibitor MG-132, but not the p38 MAPK inhibitor SB203580. All SCFAs decreased IL-6 protein release from organ cultures. CONCLUSION: In the present study propionate and butyrate were equipotent, whereas acetate was less effective, at suppressing NF-κB reporter activity, immune-related gene expression and cytokine release in vitro. Our findings suggest that propionate and acetate, in addition to butyrate, could be useful in the treatment of inflammatory disorders, including IBD. 展开更多
关键词 NEUTROPHILS Epithelial cells COLITIS Infla- mmation Short-chain fatty acids ACETATE PROPIONATE BUTYRATE NF-KB Cytokines
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Effect of lactic acid bacteria and propionic acid on conservation characteristics,aerobic stability and in vitro gas production kinetics and digestibility of whole-crop corn based total mixed ration silage 被引量:19
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作者 CHEN Lei YUAN Xian-jun +3 位作者 LI Jun-feng WANG Si-ran DONG Zhi-hao SHAO Tao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第7期1592-1600,共9页
This study was conducted to evaluate the effect of lactic acid bacteria and propionic acid on the fermentation quality, aer- obic stability and in vitro gas production kinetics and digestibility of whole-crop corn bas... This study was conducted to evaluate the effect of lactic acid bacteria and propionic acid on the fermentation quality, aer- obic stability and in vitro gas production kinetics and digestibility of whole-crop corn based totalmixed ration (TMR) silage. Total mixed ration was ensiled with four treatments: (1) no additives (control); (2) an inoculant (Lactobacillus plantarum) (L); (3) propionicacid (P); (4) propionic acid+lactic acid bacteria (PL). All treatments were ensiled in laboratory-scale silos for 45 days, and then subjected to an aerobic stability test for12 days. Further, four TMR silages were incubated in vitro with buffered rumen fluid to study in vitro gas production kinetics and digestibility. The results indicated that all TMR silages had good fermentation characteristics with low pH (〈3.80) and ammonia nitrogen (NH3-N) contents, and high lactic acid contents as well as Flieg points. Addition of L further improved TMR silage quality with more lactic acid production. Addition of P and PL decreased lactic acid and NH3-N contents of TMR silage compared to the control (P〈0.05). After 12 days aerobic exposure, P and PL silages remained stable, but L and the control silages deteriorated as indicated by a reduction in lactic acid and an increase in pH, and numbers of yeast. Compared to the control, addition of L had no effects on TMR silage in terms of 72 h cumulative gas production, in vitro dry matter digestibility, metabolizable energy, net energy for lactation and short chain fatty acids, whereas addition of PL significantly (P〈0.05) increased them. L silage had higher (P〈0.05) in vitro neutral detergent fiber digestibility than the control silage. The results of our study suggested that TMR silage prepared with whole-crop corn can be well preserved with or without additives. Furthermore, the findings of this study suggested that propionic acid is compatible with lactic acid bacteria inoculants, and when used together, although they reduced lactic acid production of TMR silage, they improved aerobic stability and in vitro nutrients digestibility of TMR silage. 展开更多
关键词 lactic acid bacteria propionic acid fermentation quality aerobic stability in vitro digestibility total mixed rationsilage
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New-found link between microbiota and obesity 被引量:26
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作者 Chandra Kanti Chakraborti 《World Journal of Gastrointestinal Pathophysiology》 CAS 2015年第4期110-119,共10页
Due to the grave pathological role of obesity, worldwide research is being continued to find out the causative factors involved in it. Recent advances in this field reveal a possible relationship between the compositi... Due to the grave pathological role of obesity, worldwide research is being continued to find out the causative factors involved in it. Recent advances in this field reveal a possible relationship between the compositional pattern of gut microbiota and genesis of obesity. Several study results have shown that short-chain fatty acids(SCFAs, microbiota-induced fermentation products) and lipopolysaccharides(LPS, an integral component of Gram negative microorganisms) play the key role in linking the two. Though several SCFAs are produced as microbiota-fermentation products, three of them, i.e., butyrate, propionate and acetate have been found to be definitely involved in obesity; though individually they are neither purely obesogenic nor antiobesogenic. Out of these, butyrate and propionate are predominantly antiobesogenic. Butyrate, though a major energy source for colonocytes, has been found to increase mitochondrial activity, prevent metabolic endotoxemia, improve insulin sensitivity, possess antiinflammatory potential, increase intestinal barrier function and protect against diet-induced obesity without causing hypophagia. Propionate has been found to inhibit cholesterol synthesis, thereby antagonizing the cholesterol increasing action of acetate, and to inhibit the expression of resistin in adipocytes. Moreover, both these SCFAs have been found to cause weight regulation through their stimulatory effect on anorexigenic gut hormones and to increase the synthesis of leptin. Unlike butyrate and propionate, acetate, which is substantially absorbed, shows more obesogenic potential, as it acts as a substrate for hepatic and adipocyte lipogenesis. High fat diet increases the absorption of LPS, which, in turn, has been found to be associated with metabolic endotoxemia and to induce inflammation resulting in obesity. Multiple independent and interrelated mechanisms have been found to be involved in such linking processes which are discussed in this review work along with some possible remedial measures for prevention of weight gain and obesity. 展开更多
关键词 MICROBIOTA OBESITY BUTYRATE PROPIONATE ACETATE
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Synthesis and Characterization of Quaternary Complex of Sm-CH_3C(CH_2OH)_2COOH-Phen 被引量:8
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作者 西鹏 王连军 黄象安 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第3期336-339,共4页
A new quaternary complex with 2,2-dihydroxymethyl propionic acid and 1,10-phenanthroline, Sm(CH3C(CH2OH)2COO)(NO3)2(phen), was synthesized in ethanol solution and characterized by elemental analysis, IR and solid-stat... A new quaternary complex with 2,2-dihydroxymethyl propionic acid and 1,10-phenanthroline, Sm(CH3C(CH2OH)2COO)(NO3)2(phen), was synthesized in ethanol solution and characterized by elemental analysis, IR and solid-state 13C NMR. The result of molar electrolytic conductivity of the complex indicates that it is non-electrolyte. Solution and thermal properties of the complex further verifies that the complex and ligant are different. In addition, the analytical results also imply that the two hydroxyl groups of 2,2-dihydroxymethyl propionic acid are not involved in the coordinate reaction. This will provide a new way for producing new multifunctional polymer materials with excellent fluorescent property. The fluorescence spectra of the complex were also studied. The main fluorescence emission peak of the complex appeared at 555, 604 and 646 nm. These fluorescent emission peaks correspond to transitions from 4G5/2 to 6H5/2, 6H7/2 and 6H9/2 energy levels of samarium(Ⅲ) ion, respectively. The most intense peak is at 646 nm, which lies in the range of absorption wavelength of chlorophyll a and chlorophyll b (600~680 nm), and it is beneficial to the crops to grow up. 展开更多
关键词 2 2-dihydroxymethyl propionic acid quaternary complex FLUORESCENCE rare earths
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Qualitative and quantitative assessment of related substances in the Compound Ketoconazole and Clobetasol Propionate Cream by HPLC-TOF-MS and HPLC 被引量:6
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作者 Wenling Yang Xiaomei Yang +6 位作者 Fanghua Shi Zhigang Liao Yongkun Liang Liangzhong Yu Ruixun Wang Qing Li Kaishun Bi 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2019年第3期156-162,共7页
Related substances in pharmaceutical formulations are associated with their safety, efficacy and stability. However, there is no overall study already published on the assessment of related substances in the Compound ... Related substances in pharmaceutical formulations are associated with their safety, efficacy and stability. However, there is no overall study already published on the assessment of related substances in the Compound Ketoconazole and Clobetasol Propionate Cream. In this work, a reliable HPLC-TOF-MS qualitative method was developed for the analysis of related substances in this preparation with a quick and easy extraction procedure. Besides the active pharmaceutical ingredients, two compounds named ketoconazole impurity B′ optical isomer and ketoconazole impurity E were identified. Furthermore, a new HPLC method for qualitative and quantitative assessment on related substances and degradation products, which were found in the stability test, was established and validated. The single standard to determine multi-components method was applied in the quantitative analysis, which was an effective way for reducing cost and improving accuracy. This study can provide a creative idea for routine analysis of quality control of the Compound Ketoconazole and Clobetasol Propionate Cream. 展开更多
关键词 Compound KETOCONAZOLE and CLOBETASOL PROPIONATE Cream KETOCONAZOLE IMPURITY B' optical isomer KETOCONAZOLE IMPURITY E Quality control HPLC-TOF-MS HPLC
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Study on Ni/C catalysts for vapor phase carbonylation of ethanol 被引量:4
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作者 Qing Zhang Huifang Wang +3 位作者 Guosong Sun Kelin Huang Weiping Fang Yiquan Yang 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2008年第4期355-358,共4页
Activated carbon-supported Ni catalysts for vapor phase carbonylation of ethanol to propionic acid in the presence of ethyl iodide as promoter were investigated. Under optimum reaction conditions, the conversions of c... Activated carbon-supported Ni catalysts for vapor phase carbonylation of ethanol to propionic acid in the presence of ethyl iodide as promoter were investigated. Under optimum reaction conditions, the conversions of carbon monoxide and ethanol were measured to be 81.4% and 98.4%, respectively, while the selectivity for propionic acid was found to be 98.65%. The catalyst was stable within 48 h on stream. XRD and XPS methods were used to characterize the structures and surface properties of the fresh and tested catalysts. The characterization results indicated that aggregation of nickel particles and formation of nickel iodide on the catalyst surface should be responsible for the deactivation of the catalysts. 展开更多
关键词 ETHANOL CARBONYLATION NICKEL propionic acid DEACTIVATION
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In vitro investigation of the effect of dairy propionibacteria on rumen pH,lactic acid and volatile fatty acids 被引量:4
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作者 Jianbiao Luo Chaminda Senaka Ranadheera +2 位作者 Stuart King Craig Evans Surinder Baines 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第7期1566-1575,共10页
Ruminal acidosis is a prevalent disorder in ruminants such as dairy cows and feedlot beef cattle, caused primarily by the inclusion of a high percentage of readily fermentable concentrates in the diet. The disorder pr... Ruminal acidosis is a prevalent disorder in ruminants such as dairy cows and feedlot beef cattle, caused primarily by the inclusion of a high percentage of readily fermentable concentrates in the diet. The disorder presents as an accumulation of lactic acid, a decrease of pH in the rumen and a subsequent imbalance of the rumen fermentation process with detrimental impacts on the animal's health and productivity. Dairy propionibacteria, a group of bacteria characterised by utilization of lactic acid as the favoured carbon source, with propionic acid produced as a by-product, were evaluated in this study as potential direct-fed microbials for use in controlling ruminal acidosis. Acidosis was simulated by introduction of high concentrations of lactic acid into rumen fluid samples and a multi-strain in vitro analysis was conducted, whereby changes in pH and lactic acid metabolism were compared in identical acidified rumen samples, following inoculation with various propionibacteria. This was followed by a study to evaluate the effect of bacterial inoculation dosage on acid metabolism. The results indicated that lactic acid levels in the rumen fluid were significantly reduced, and propionic acid and acetic acid concentrations both significantly increased, following addition of propionibacteria. Significant 'between strains' differences were observed, with Propionibacterium acidopropionici 341, Propionibacterium freudenreichfi CSCC 2207, Propionibacterium jensenfi NCFB 572 and P. jensenii 702 each producing more rapid reduction of lactic acid concentration than P. freudenreich# CSCC 2206, P. acidopropionici ATCC 25562 and Propionibacterium thoenii ATCC 4874. Furthermore, the efficacy of this application was dosage related, with the rates of reduction in lactic acid levels and production of propionic acid, both significantly greater for the higher (10^10 cfu mL-1) compared with lower (10^5 cfu mL-1) dosage inoculation. The results confirmed that the introduction of propionibacteria could promote more rapid reduction of lactic acid levels than would occur without their addition, demonstrating their potential in controlling ruminal acidosis. 展开更多
关键词 PROBIOTICS ruminal acidosis lactic acid propionic acid dairy Propionibacterium
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Optimization of Propionic Acid Feeding for Production of Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) in Fed-Batch Culture of Ralstonia eutropha 被引量:3
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作者 Longan SHANG Jin Hwan Do +2 位作者 范代娣 姜岷 Ho Nam CHANG 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2003年第2期220-223,共4页
The feeding method of propionic acid for production ofpoly(3-hydroxybutyrate-co-3-hydro xyvalerate) [P(3HB-co-3HV)] by fed-batch culture of Ralstoniaeutropha was optimized to achieve high cell density and high 3HV yie... The feeding method of propionic acid for production ofpoly(3-hydroxybutyrate-co-3-hydro xyvalerate) [P(3HB-co-3HV)] by fed-batch culture of Ralstoniaeutropha was optimized to achieve high cell density and high 3HV yield. Effects of different feedingstrategies of propionic acid on the production of P(3HB-co-3HV) were investigated. A decline ofspecific synthesis rate of copolymer and the yield of 3HV unit from propionic acid were observed dueto the propionic acid accumulation in culture broth when the feeding solution with highP/G(propionic acid to glucose) ratio was employed. It was further confirmed by controlling propionicacid concentration at a low level in the separate feeding of propionic acid. An optimal feedingstrategy was demonstrated to reduce the propionic acid accumulation. The cell concentration,P(3HB-co-3HV) productivity and 3HV unit fraction reached to 163.9kg·m^(-3), 1.8kg·m^(-3)·h^(-1),and 10.6%(by mass), respectively, resulting in a yield of 0.33g HV per g propionic acid. 展开更多
关键词 biodegradable polyester feeding strategy P(3HB-co-3HV) propionic acid ralstonia eutropha
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Synthesis and Crystal Structure of O,O-Dimethyl-N-(β-triphenylgermanyl)propionyl-α- aminobenzylphosphonates 被引量:3
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作者 叶勇 曾强 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2001年第3期195-198,共4页
The title compound (C30H32NO4PGe), O,O-dimethyl-N-(β-triphenylgermanyl) propionyl-α-aminobenzylphosphonates was synthesized by a convenient method, and its crystal structure was determined by single-crystal X-ray di... The title compound (C30H32NO4PGe), O,O-dimethyl-N-(β-triphenylgermanyl) propionyl-α-aminobenzylphosphonates was synthesized by a convenient method, and its crystal structure was determined by single-crystal X-ray diffraction. The crystal is triclinic, space group P-1 with parameters: a=9.7753(5), b=11.5773(5), c=13.5059(6) ?, α=104.185(1),β= 95.971(1), γ =96.727(1)°, V=1457.63(12) ?3, Z=2, Mr=574.13, Dc=1.308 g/cm3, λ=0.71073 ?, μ = 1.139mm-1, and F(000)=596. The structure was solved by direct methods. The structure was refined to R=0.0257, wR=0.0705 for 5080 observed reflections with I >2σ(I).The result of structure analysis indicates that atom Ge is sp3 hydridized because the arrangement of the four carbon atoms bonded to it is a distorted tetrahedron. The geometry of the three phenyl groups linking with the Ge atom looks like a propeller form. 展开更多
关键词 crystal structure α-aminobenzylphosphonates β-triphenylgermanyl propionic acid SYNTHESIS
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Effect of steam-flaking on chemical compositions,starch gelatinization,in vitro fermentability,and energetic values of maize,wheat and rice 被引量:15
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作者 QIAO Fu-qiang WANG Fei +3 位作者 REN Li-ping ZHOU Zhen-ming MENG Qing-xiang BAO Yu-hong 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第5期949-955,共7页
Intact and steam-flaked grains of maize,wheat and rice(with whole hulls) were analyzed for chemical composition,starch gelatinization degree(SGD) and in vitro fermentation characteristics to investigate the influe... Intact and steam-flaked grains of maize,wheat and rice(with whole hulls) were analyzed for chemical composition,starch gelatinization degree(SGD) and in vitro fermentation characteristics to investigate the influence of cereal type and steam-flaking(SF) processing on their nutritive values.The treatments were arranged in a 3×2 factorial design.Obvious differences(P〈0.001) in chemical composition and energetic values were observed among the different cereal types.SGD and gas production(GP) rate was significantly increased(P〈0.001) by SF processing.SF processing also increased(P〈0.01) the proportion of propionic acid and decreased the acetic:propionic acid ratio in vitro.Steam-flaking also increased organic matter digestibility and the energetic value of the cereal grains,especially rice.Based on these results,rice probably is more amendable to SF processing than maize and wheat.In conclusion,it is feasible to partially substitute maize grain with wheat or rice in ruminant diets,and steam-flaking can significantly improve the nutritional value of wheat and rice grains. 展开更多
关键词 maize wheat starch steam cereal grains propionic Wheat proportion partially
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Synthesis and Structure of Propionate-bridged Mixed-metal Cluster Compound: MoW_2O_2 (O_2CC_2H_5)_6 (H_2O)_3 ZnBr_4·4H_2O 被引量:3
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作者 刘晃 徐立 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1994年第1期52-55,共4页
The heterotrinuclear cluster compound [MoW_2O_2 (O_2CC_2H_5 )_6-( H_2O)_3] ZnBr4·4H_2O was prepared by the redox reaction of Mo (CO)_6 with Na_2W_O4 in propionic anhydride. The crystal is monoclinic of space grou... The heterotrinuclear cluster compound [MoW_2O_2 (O_2CC_2H_5 )_6-( H_2O)_3] ZnBr4·4H_2O was prepared by the redox reaction of Mo (CO)_6 with Na_2W_O4 in propionic anhydride. The crystal is monoclinic of space group P2/c with a =16. 334(4) , b= 9. 657(5) , c=19. 889(9) ,β= 139. 79 (5)°,V= 2026 (2)  ̄3 , Z=2 , D_c=2. 30 g/cm ̄3 μ(MoKa) =106. 6 cm ̄(-1) ,F(000)=1176 ,final R=0. 065 and R_ω=0. 072 for 1964 reflections with I≥3σ(I). In the structure of cation [MoW_2O_2 (O_2CC_2H_5 )_6 (H_2O)_3] ̄(2+) molybdenum and tungsten atoms are statistically disordered. Three metal atoms form an equilateral triangle with the distance of M-M being 2. 735. 展开更多
关键词 SYNTHESIS crystal structure mixed-metal cluster Mo-W propionate compound
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Synthesis and Crystal Structure of 2-[(2-Chloropyridin-4-yl)oxy]-3,3-diphenyl-3-methoxypropionic Acid 被引量:2
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作者 于秀玲 赵桂龙 +2 位作者 谭初兵 邵华 徐为人 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第4期545-549,共5页
The title compound was synthesized and its crystal structure was determined by single-crystal X-ray diffraction.The crystal is of orthorhombic system(C21H18ClNO4,Mr = 383.81),space group Pca21 with a = 13.913(3),b... The title compound was synthesized and its crystal structure was determined by single-crystal X-ray diffraction.The crystal is of orthorhombic system(C21H18ClNO4,Mr = 383.81),space group Pca21 with a = 13.913(3),b = 10.273(2),c = 26.488(5),V = 3786.1(13) 3,Z = 8,Dc = 1.347 g/cm3,F(000) = 1600,μ = 0.228 mm-1,the final R = 0.0550 and wR = 0.1278 for 5065 observed reflections(I 2σ(I)).The title compound in a racemic form was found to exist as a mixture of two enantiomers in an equal ratio in the unit cell.The intermolecular hydrogen bonds link the molecules in a head-to-end manner to generate an infinite chain. 展开更多
关键词 synthesis crystal structure PYRIDINE propionic acid ETR antagonist
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硅胶键合N-丙基哌嗪n-丙酸钠作为可循环使用催化剂催化4H-吡喃衍生物合成(英文) 被引量:2
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作者 Khodabakhsh Niknam Nassim Borazjani +1 位作者 Reza Rashidian Abbas Jamali 《催化学报》 SCIE EI CAS CSCD 北大核心 2013年第12期2245-2254,共10页
Silica‐bonded N‐propylpiperazine sodium n‐propionate(SBPPSP) was found to act as an efficient solid base for the preparation of a series of 4H‐benzo[b]pyran derivatives. SBPPSP was used as a recyclable heterogeneo... Silica‐bonded N‐propylpiperazine sodium n‐propionate(SBPPSP) was found to act as an efficient solid base for the preparation of a series of 4H‐benzo[b]pyran derivatives. SBPPSP was used as a recyclable heterogeneous solid base catalyst for the synthesis of 3,4‐dihydropyrano[c]chromenes, 2‐amino‐4H‐pyrans, 1,4‐dihydropyrano[2,3‐c]pyrazoles, and 2‐amino‐4H‐benzo[e]‐chromenes via the condensation reaction of dimedone, ethyl acetoacetate, 3‐methyl‐1‐phenyl‐1H‐pyrazol‐5(4H)‐ one, and α‐naphthol, respectively, with aromatic aldehydes and malononitrile in refluxing aqueous ethanol. The heterogeneous solid base showed similar efficiency when reused in consecutive reactions. 展开更多
关键词 Silica‐bonded n‐propylpiperazine sodium n‐propionate Heterogeneous solid base catalyst ALDEHYDE 4H‐Pyran derivative MALONONITRILE
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Naproxen-induced liver injury 被引量:2
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作者 Sharif Ali Jason D Pimentel 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2011年第5期552-556,共5页
BACKGROUND: Nonsteroidal anti-inflammatory drugs (NSAIDs) have been reported to induce liver injury. Patterns of the injury usually range from mild elevations of liver enzymes to sometimes severe fulminant hepatic fai... BACKGROUND: Nonsteroidal anti-inflammatory drugs (NSAIDs) have been reported to induce liver injury. Patterns of the injury usually range from mild elevations of liver enzymes to sometimes severe fulminant hepatic failure. Likewise, naproxen is a propionic acid derivative NSAID that was introduced in 1980 and has been available as an over-the- counter medication since 1994, but has rarely been reported to cause liver injury. METHODS: We treated a 30-year-old woman with jaundice and intractable pruritus that developed shortly after taking naproxen. We reviewed the medical history and liver histopathology of the patient as well as all previously published case reports of naproxen-associated liver toxicity in the English language literature. RESULTS: The liver biochemical profile of the patient revealed a mixed cholestasis and hepatitis pattern. Consecutive liver biopsies demonstrated focal lobular inflammation, hepatocyte drop-out, and a progressive loss of the small interlobular bile ducts (ductopenia). The biopsy performed two years after onset of the disease showed partial recovery of a small number of bile ducts; however, 10 years passed before the biochemical profile returned to near normal. CONCLUSIONS: Naproxen-associated liver toxicity remains a rare entity, but should be considered in any patient presenting with cholestasis shortly after its use. Liver injury is most commonly seen in a mixed pattern characterized by cholestasis and hepatitis. The resulting liver damage may take years to resolve. 展开更多
关键词 NAPROXEN ductopenia vanishing bile duct syndrome propionic acid liver injury
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An efficient route towards R-2-phenoxypropionic acid synthesis for biotransformative production of R-2-(4-hydroxyphenoxy)propionic acid 被引量:3
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作者 Haiyan Zhou Yizuo Li +4 位作者 Rui Jiang Xianlin Wang Yuanshan Wang Yaping Xue Yuguo Zheng 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第4期315-323,共9页
R2(4hydroxyphenoxy)propionic acid(RHPPA)is a key intermediate for the synthesis of classic herbicides with high selectivity against grassy weed.The main route for RHPPA biosynthesis is to hydroxylate the substrate R2p... R2(4hydroxyphenoxy)propionic acid(RHPPA)is a key intermediate for the synthesis of classic herbicides with high selectivity against grassy weed.The main route for RHPPA biosynthesis is to hydroxylate the substrate R2phenoxypropionic acid(RPPA)at C4 position with microbes.In order to provide sufficient RPPA for the industrial production of RHPPA,an effective RPPA synthesis method was established and optimized in this work.The synthesis process mainly consisted of two steps:(1)synthesis of S2chloropropionic acid from Lalanine via diazotization and chlorination reactions;and(2)synthesis of RPPA from S2chloropropionic acid and phenol via etherification reaction.The optimal reaction conditions were as follows:HCl:NaNO_(2):KI:LAla=2.0:1.2:0.7:1.0(in molar),125℃reflux for 1.5 h,with KI as catalyst,and KI:S2chloropropionic acid:phenol=0.075:1.2:1.0(in molar).Under these conditions,an improved molar conversion rate(74.9%,calculated in phenol)was achieved.After extraction using anionic exchange resin Amberlite IRA400(CI),RPPA product with a purity of 95.08%was obtained.The purified RPPA was identified and evaluated in the application of the biotransformative production of RHPPA.The results indicated that the synthesized RPPA supported the RHPPA biosynthesis with a comparable yield as that of the standard RPPA.The RPPA synthesis method provided herein exhibited the advantages of low price and easy availability of raw materials,less toxicity of reagents,simple manipulations,and low equipment/instrument requirements. 展开更多
关键词 R-2-phenoxypropionic acid R-2-(4-hydroxyphenoxy)propionic acid BIOSYNTHESIS S-2-chloropropionic acid
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Visible-Light-Induced Selective Hydrocarboxylation of Alkynes with Formate 被引量:2
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作者 Xu Hui Jiang Huixian +2 位作者 Kan Lei Xu Pei Zhu Xu 《有机化学》 SCIE CAS CSCD 北大核心 2024年第10期3241-3248,共8页
An efficient and sustainable protocol for regioselective hydrocarboxylation of alkynes to construct diverse propionic acid derivatives is disclosed.Under photoinduced conditions,the anti-Markovnikov hydrocarboxylation... An efficient and sustainable protocol for regioselective hydrocarboxylation of alkynes to construct diverse propionic acid derivatives is disclosed.Under photoinduced conditions,the anti-Markovnikov hydrocarboxylation of alkynes was realized with CO_(2) radical anion in-situ generated from formate as both a carbonyl source and a reductant.The collaboration between photosensitizer and hydrogen atom transfer catalyst promoted the catalytic cycle to work smoothly,giving a broad substrate scope including terminal and internal alkynes.The Giese radical addition of CO_(2) radical anion to the C—C triple bond is the key step to initiate the reaction. 展开更多
关键词 FORMATE CO_(2)radical anion HYDROCARBOXYLATION visible-light catalysis aryl propionic acids
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