资源类型

期刊论文 58

会议视频 2

年份

2023 6

2022 6

2021 6

2020 3

2019 3

2018 3

2017 5

2016 3

2015 6

2014 4

2013 2

2012 3

2011 1

2010 5

2009 1

2008 1

2007 1

2000 1

展开 ︾

关键词

医学 2

&gamma 1

CCK-8 实验 1

MTT 实验 1

三元结构 1

产乙酸菌 1

内涵性改造 1

农业 1

十二烷基硫酸钠&ndash 1

射线灭菌 1

微生物电化学 1

有机酸 1

氨基酸 1

氨基酸分析 1

氨基酸工业 1

玉米醇溶蛋白 1

电发酵 1

电活性微生物 1

电渗析 1

展开 ︾

检索范围:

排序: 展示方式:

Catalytic conversion of biomass-derived compounds to various amino acids: status and perspectives

《化学科学与工程前沿(英文)》 2023年 第17卷 第7期   页码 817-829 doi: 10.1007/s11705-022-2254-z

摘要: Amino acids are important nitrogen-containing chemicals that have a variety of applications. Currently, fermentation is the widely employed method to produce amino acids; however, the products are mostly limited to natural amino acids in the L-configuration. Catalytic synthesis is an alternative approach for the synthesis of amino acids with different types and configurations, where the use of renewable biomass-based feedstocks is highly attractive. To date, several lignocellulose and triacylglycerol-derived intermediates, typically α-keto acids and α-hydroxyl acids, have been transformed into amino acids via the amination reaction in the presence of additional nitrogen sources (i.e., NH3·H2O). Making full use of inherent nitrogen in biomass (i.e., chitin and protein) to produce amino acids avoids the use of extra nitrogen sources and meets the requirements of green chemistry, which is attracting increasing attention. In this review, we summarize different chemical-catalytic systems for the transformation of biomass to amino acids. An outlook on the challenges and opportunities for more effective production of amino acids from biomass by catalytic methods is provided.

关键词: biomass     amino acids     chitin     nitrogen-containing compounds     lignocellulose    

Anaerobic digestion of sludge by different pretreatments: Changes of amino acids and microbial community

《环境科学与工程前沿(英文)》 2022年 第16卷 第2期 doi: 10.1007/s11783-021-1458-7

摘要:

•Tryptophan protein, and aromatic protein I/II were the key identified proteins.

关键词: Sludge pretreatments     Dissolved organic nitrogen     Proteins     Amino acids     Structural equation model     Metagenomic sequencing analysis.    

Insights into the changes of amino acids, microbial community, and enzymatic activities related with

《环境科学与工程前沿(英文)》 2023年 第17卷 第3期 doi: 10.1007/s11783-023-1635-y

摘要:

● The highest seed germination index was achieved at 0.3 g/g total solids of food waste.

关键词: Composting     Food waste     Amino acids     Microbial community     Enzymatic activity     Nutrient quality    

Insulin resistance and the metabolism of branched-chain amino acids

null

《医学前沿(英文)》 2013年 第7卷 第1期   页码 53-59 doi: 10.1007/s11684-013-0255-5

摘要:

Insulin resistance (IR) is a key pathological feature of metabolic syndrome and subsequently causes serious health problems with an increased risk of several common metabolic disorders. IR related metabolic disturbance is not restricted to carbohydrates but impacts global metabolic network. Branched-chain amino acids (BCAAs), namely valine, leucine and isoleucine, are among the nine essential amino acids, accounting for 35% of the essential amino acids in muscle proteins and 40% of the preformed amino acids required by mammals. The BCAAs are particularly responsive to the inhibitory insulin action on amino acid release by skeletal muscle and their metabolism is profoundly altered in insulin resistant conditions and/or insulin deficiency. Although increased circulating BCAA concentration in insulin resistant conditions has been noted for many years and BCAAs have been reported to be involved in the regulation of glucose homeostasis and body weight, it is only recently that BCAAs are found to be closely associated with IR. This review will focus on the recent findings on BCAAs from both epidemic and mechanistic studies.

关键词: branched-chain amino acids     leucine     isoleucine     valine     insulin resistance    

Valorisation of protein waste: An enzymatic approach to make commodity chemicals? ?

Madura B. A. Kumar, Yuan Gao, Wei Shen, Lizhong He

《化学科学与工程前沿(英文)》 2015年 第9卷 第3期   页码 295-307 doi: 10.1007/s11705-015-1532-4

摘要: Protein-rich waste is an abundantly available resource that is currently used mainly as animal feed and fertilizers. Valorisation of protein waste to higher value products, particularly commodity chemicals such as precursors for polymers, has attracted significant research efforts. Enzyme-based approaches, being environmentally-friendly compared to their chemical counterparts, promise sustainable processes for conversion of protein waste to valuable chemicals. This review provides a general overview on valorisation of protein waste and then further summarises the use of enzymes in different stages of the valorisation process—protein extraction and hydrolysis, separation of individual amino acids and their ultimate conversion into chemicals. Case studies of enzymatic conversion are presented for different amino acids including glutamic acid, lysine, phenylalanine, tyrosine, arginine and aspartic acid. The review compares the different enzyme reactors and operation modes for amino acid conversion. The emerging opportunities and challenges in the field are discussed: engineering powerful enzymes and integrating innovative processes for industrial application at a low cost.

关键词: amino acids     protein waste     reactor     conversion     commodity chemicals     enzymes    

从我国人民膳食结构演变谈三元结构农业的内涵性改造

张子仪

《中国工程科学》 2000年 第2卷 第8期   页码 35-39

摘要:

由于近20年来全国人民膳食中的肉、蛋、奶比重的不断增加,已经在减缓我国人民对口粮的压力方面发挥着巨大作用。为了争取我国人民对动物性蛋白质的消费量达到发展中国家的先进水平,预计在中长期内,我国饲用蛋白质资源将缺口一半;其中赖氨酸缺口更大,走工业化的途径,在入世后很难形成竞争性优势。三元结构农业的内涵性改造,是结合国情国力解决饲用蛋白质资源不足问题的有效途径。

关键词: 三元结构     膳食结构     农业     内涵性改造     氨基酸工业    

Bile acids and their effects on diabetes

Cynthia Rajani, Wei Jia

《医学前沿(英文)》 2018年 第12卷 第6期   页码 608-623 doi: 10.1007/s11684-018-0644-x

摘要: Diabetes is a widespread, rapidly increasing metabolic disease that is driven by hyperglycemia. Early glycemic control is of primary importance to avoid vascular complications including development of retinal disorders leading to blindness, end-stage renal disease, and accelerated atherosclerosis with a higher risk of myocardial infarction, stroke and limb amputations. Even after hyperglycemia has been brought under control, “metabolic memory,” a cluster of irreversible metabolic changes that allow diabetes to progress, may persist depending on the duration of hyperglycemia. Manipulation of bile acid (BA) receptors and the BA pool have been shown to be useful in establishing glycemic control in diabetes due to their ability to regulate energy metabolism by binding and activating nuclear transcription factors such as farnesoid X receptor (FXR) in liver and intestine as well as the G-protein coupled receptor, TGR5, in enteroendocrine cells and pancreatic -cells. The downstream targets of BA activated FXR, FGF15/21, are also important for glucose/insulin homeostasis. In this review we will discuss the effect of BAs on glucose and lipid metabolism and explore recent research on establishing glycemic control in diabetes through the manipulation of BAs and their receptors in the liver, intestine and pancreas, alteration of the enterohepatic circulation, bariatric surgery and alignment of circadian rhythms.

关键词: bile acids     metabolic memory     diabetes     circadian rhythm     bariatric surgery    

Immobilization of penicillin G acylase onto amino-modified silica hydrogel

Weibing Dong, Huining HE, Junbo Gong, Victor C. YANG,

《化学科学与工程前沿(英文)》 2010年 第4卷 第1期   页码 87-90 doi: 10.1007/s11705-009-0298-y

摘要: Amino-modified silica hydrogel (N-MSHG) was prepared by a simple sol-gel processing via the co-condensation of commercial silica sol with 3-aminopropyltrie-oxysilane. Penicillin G acylase (PGA), a model enzyme, was covalently immobilized onto the N-MSHG and then was used for the enzymatic synthesis of amoxicillin. The samples were characterized by Nitrogen sorption analysis, FT-IR and thermal gravimetric analysis (TGA). The results showed that the amino-modified gel was a mesoporous material with an average pore size of 12.64±0.17nm. The immobilization process was efficient and the immobilized enzyme showed high catalytic efficiency. The yield of the synthesis of amoxicillin in aqueous media was 38% for 2.5h. This sol-gel preparation is simple and shows prominent potential value in industrial processing.

关键词: gravimetric     amino-modified     efficient     Amino-modified     amoxicillin    

Continuous amino-functionalized University of Oslo 66 membranes as efficacious polysulfide barriers for

《化学科学与工程前沿(英文)》 2023年 第17卷 第2期   页码 194-205 doi: 10.1007/s11705-022-2206-7

摘要: The shuttle effect of soluble polysulfides is a serious problem impeding the development of lithium−sulfur batteries. Herein, continuous amino-functionalized University of Oslo 66 membranes supported on carbon nanotube films are proposed as ion-permselective interlayers that overcome these issues and show outstanding suppression of the polysulfide shuttle effect. The proposed membrane material has appropriately sized pores, and can act as ionic sieves and serve as barriers to polysulfides transport while allowing the passage of lithium ions during electrochemical cycles, thereby validly preventing the shuttling of polysulfides. Moreover, a fast catalytic conversion of polysulfides is also achieved with the as-developed interlayer. Therefore, lithium−sulfur batteries with this interlayer show a desirable initial capacity of 999.21 mAh·g–1 at 1 C and a durable cyclic stability with a decay rate of only 0.04% per cycle over 300 cycles. Moreover, a high area capacity of 4.82 mAh·cm–2 is also obtained even under increased sulfur loading (5.12 mg·cm–2) and a lean-electrolyte condition (E/S = 4.8 μL·mg–1).

关键词: lithium−sulfur batteries     amino-functionalized University of Oslo 66 membrane     polysulfide     interlayer    

Synthesis and anticancer activity of (+)-nopinone-based 2-amino-3-cyanopyridines

Shengliang LIAO,Shibin SHANG,Minggui SHEN,Xiaoping RAO,Hongyan SI,Jie SONG,Zhanqian SONG

《农业科学与工程前沿(英文)》 2015年 第2卷 第4期   页码 335-340 doi: 10.15302/J-FASE-2015079

摘要: Twelve (+)-nopinone-based 2-amino-3-cyanopyridines 4a–l were synthesized from (–)-β-pinene. The structures of these compounds were characterized by FT-IR, H NMR, and ESI-MS. All the compounds were tested for their anticancer activity against lung cancer cell line A549, gastric cancer cell line MKN45 and breast cancer cell line MCF7 by MTT method, respectively. The results showed that compounds 4f, 4j and 4k had promising anticancer activity against these cancer cell lines, in particular, compound 4f exhibited broad-spectrum and highly efficient anticancer activity against cell lines A549, MKN45 and MCF7 with IC of 23.78, 67.61 and 53.87 µmol·L , respectively. The preliminary analysis of the structure activity relationship implied that the Br or Cl substituted group of the benzene ring in these derivatives significantly contributed to the anticancer activity.

关键词: b-pinene     nopinone     synthesis     2-amino-3-cyanopyridine     anticancer    

Characterization of soil low-molecular-weight organic acids in the Karst rocky desertification region

Xiaoliang LI, Xiaomin CHEN, Xia LIU, Lianchuan ZHOU, Xinqiang YANG

《环境科学与工程前沿(英文)》 2012年 第6卷 第2期   页码 195-203 doi: 10.1007/s11783-012-0391-1

摘要: Soil low-molecular-weight (LMW) organic acids play important roles in the soil-forming process and the cycling of nutrients in Karst regions. In this study, we quantified the contents of LMW organic acids (including lactate, acetate, formate, malate, and oxalate) in soil solution over the Karst region of Guizhou Province, China using ion chromatography. The concentration of total LMW organic acids in topsoil solution ranged from 0.358 to 1.823 μmol·g , with an average of 0.912 μmol·g . The mean concentrations of lactate, acetate, formate, malate, and oxalate were 0.212±0.089, 0.302±0.228, 0.301±0.214, 0.014±0.018 and 0.086±0.118 μmol·g , respectively. There were also significant difference in the contents of these acids among four phases of rocky desertification, and their concentrations decreased with the aggravation of rocky desertification. The concentrations of the LMW organic acids were significantly positive correlated each other. Significant positive correlations were also observed among individual LMW organic acids in soil solution, and between them and soil available P, available K, exchangeable Ca, respectively. Furthermore, the concentrations of LMW organic acids were significantly positively correlated with inorganic anions (chlorides, nitrates, and sulfates) in Karst topsoil solution. Therefore, the concentrations of soil LMW organic acids might be one of driving force in the Karst rock desertification process in Guizhou Province.

关键词: Karst rocky desertification     low-molecular-weight (LMW) organic acids     distribution characteristics     soil    

Improvement in the synthesis of 2-(5-amino-1,2,4-thiadiazol-3-yl)-2-(Z)-methoxyiminoacetic acid 2-benzothiazolyl

GAO Shihao, SUN Chenghui, ZHAO Xinqi, GAO Changquan

《化学科学与工程前沿(英文)》 2008年 第2卷 第1期   页码 80-84 doi: 10.1007/s11705-008-0017-0

摘要: 2-(5-Amino-1,2,4-thiadiazol-3-yl)-2-(Z)-methoxyiminoacetic acid 2-benzothiazolyl thioester(III), an important intermediate of the fourth generation cephalosporins, was efficiently synthesized by reacting 2-(5-amino-1,2,4-thiadiazol-3-yl)-2-(Z)-methoxyiminoacetic acid (I) with 2,2′-dibenzothiazole disulfide (II) in the presence of triphenylphosphine. Effects of reaction time, temperature, solvents, catalysts and feeding molar ratio on the yield and quality of products were investigated, and an improved procedure suitable for industrial production was established. Using 1,2-dichloroethane as solvent, triphenylphosphine as reducer, and triethylamine as catalyst, (I) : (II) : (triphenylphosphine) = 1.0 : 1.0 : 1.0, the product was obtained at room temperature in 98.1% yield. The purity of the product without further purification is 98.7% determined by HPLC method. This procedure could be a suitable alternative to the traditional processes because of its easy handling, high yield and low cost.

关键词: 5-Amino-1     2     4-thiadiazol-3-yl     1     2-dichloroethane     important intermediate     2-benzothiazolyl thioester     temperature    

Optimization of pretreatment of Jatropha oil with high free fatty acids for biodiesel production

Supriyono SUWITO, Giuliano DRAGONE, Hary SULISTYO, Bardi MURACHMAN, Suryo PURWONO, José TEIXEIRA

《化学科学与工程前沿(英文)》 2012年 第6卷 第2期   页码 210-215 doi: 10.1007/s11705-012-1282-5

摘要: A central composite rotatable design and response surface methodology were used in order to investigate the individual and combined effects of the ethanol-to-oil ratio, H SO concentration, temperature and time of reaction on the reduction of free fatty acid (FFA) in jatropha oil. A quadratic polynomial model relating the reaction variables with FFA reduction was developed, presenting a good coefficient of determination ( = 0.893). For reducing FFA to less than 1%, the optimal combination was found to be 0.62 v·v ethanol-to-oil ratio (14.9 v·v ethanol-to-FFA ratio), 1.7% v·v H SO concentration, and 79 min reaction time at a reaction temperature of 54°C. These results are of great relevance to maximize methyl esters formation by transesterification using an alkaline catalyst.

关键词: biodiesel     biofuel     esterification     free fatty acids     jatropha curcas oil    

Mild and highly regioselective synthesis of biaryl acids via Rh(I)-catalyzed cross-dehydrogenative couplingof benzoic acids using sodium chlorite as oxidant

Yun Liu, Youquan Zhu, Chaojun Li

《化学科学与工程前沿(英文)》 2018年 第12卷 第1期   页码 3-8 doi: 10.1007/s11705-017-1693-4

摘要: A mild and efficient synthesis for the biaryl acids via rhodium-catalyzed cross-dehydrogenative coupling reaction has been developed. This novel protocol with sodium chlorite as an oxidant featured many advantages such as mild reaction conditions, high regioselectivity, tolerance of various functional groups, and good to excellent yields.

关键词: biaryl acids     cross-dehydrogenative coupling     rhodium-catalyzed    

Visualization of amino acid composition differences between processed protein from different animal species

Xingfan ZHOU,Zengling YANG,Longjian CHEN,Lujia HAN

《农业科学与工程前沿(英文)》 2016年 第3卷 第2期   页码 171-179 doi: 10.15302/J-FASE-2016095

摘要: Amino acids are the dominant organic components of processed animal proteins, however there has been limited investigation of differences in their composition between various protein sources. Information on these differences will not only be helpful for their further utilization but also provide fundamental information for developing species-specific identification methods. In this study, self-organizing feature maps (SOFM) were used to visualize amino acid composition of fish meal, and meat and bone meal (MBM) produced from poultry, ruminants and swine. SOFM display the similarities and differences in amino acid composition between protein sources and effectively improve data transparency. Amino acid composition was shown to be useful for distinguishing fish meal from MBM due to their large concentration differences between glycine, lysine and proline. However, the amino acid composition of the three MBMs was quite similar. The SOFM results were consistent with those obtained by analysis of variance and principal component analysis but more straightforward. SOFM was shown to have a robust sample linkage capacity and to be able to act as a powerful means to link different sample for further data mining.

关键词: self-organizing feature maps     visualization     processed animal proteins (PAPs)     amino acid    

标题 作者 时间 类型 操作

Catalytic conversion of biomass-derived compounds to various amino acids: status and perspectives

期刊论文

Anaerobic digestion of sludge by different pretreatments: Changes of amino acids and microbial community

期刊论文

Insights into the changes of amino acids, microbial community, and enzymatic activities related with

期刊论文

Insulin resistance and the metabolism of branched-chain amino acids

null

期刊论文

Valorisation of protein waste: An enzymatic approach to make commodity chemicals? ?

Madura B. A. Kumar, Yuan Gao, Wei Shen, Lizhong He

期刊论文

从我国人民膳食结构演变谈三元结构农业的内涵性改造

张子仪

期刊论文

Bile acids and their effects on diabetes

Cynthia Rajani, Wei Jia

期刊论文

Immobilization of penicillin G acylase onto amino-modified silica hydrogel

Weibing Dong, Huining HE, Junbo Gong, Victor C. YANG,

期刊论文

Continuous amino-functionalized University of Oslo 66 membranes as efficacious polysulfide barriers for

期刊论文

Synthesis and anticancer activity of (+)-nopinone-based 2-amino-3-cyanopyridines

Shengliang LIAO,Shibin SHANG,Minggui SHEN,Xiaoping RAO,Hongyan SI,Jie SONG,Zhanqian SONG

期刊论文

Characterization of soil low-molecular-weight organic acids in the Karst rocky desertification region

Xiaoliang LI, Xiaomin CHEN, Xia LIU, Lianchuan ZHOU, Xinqiang YANG

期刊论文

Improvement in the synthesis of 2-(5-amino-1,2,4-thiadiazol-3-yl)-2-(Z)-methoxyiminoacetic acid 2-benzothiazolyl

GAO Shihao, SUN Chenghui, ZHAO Xinqi, GAO Changquan

期刊论文

Optimization of pretreatment of Jatropha oil with high free fatty acids for biodiesel production

Supriyono SUWITO, Giuliano DRAGONE, Hary SULISTYO, Bardi MURACHMAN, Suryo PURWONO, José TEIXEIRA

期刊论文

Mild and highly regioselective synthesis of biaryl acids via Rh(I)-catalyzed cross-dehydrogenative couplingof benzoic acids using sodium chlorite as oxidant

Yun Liu, Youquan Zhu, Chaojun Li

期刊论文

Visualization of amino acid composition differences between processed protein from different animal species

Xingfan ZHOU,Zengling YANG,Longjian CHEN,Lujia HAN

期刊论文