通讯机构：
[Liu, XD ; Zhang, Y ] H;Hunan Agr Univ, Coll Food Sci & Technol, Changsha 410128, Peoples R China.;Hunan Acad Forestry, State Key Lab Utilizat Woody Oil Resource, Changsha 410004, Peoples R China.
关键词：
Camellia oleifera shell;Acidic deep eutectic solvents;Microwave-assisted;Lignin;Lignin nanoparticles
摘要：
Camellia oleifera shell (COS) is a waste biomass resource and abundant in lignin. Effective fractionation and valorization of lignin is of great significance. In this work, choline chloride (ChCl) and allyl trimethylammonium chloride (ATMAC) as hydrogen bond acceptors, and lactic acid (LA), acetic acid (AA) and oxalic acid (OA) as hydrogen bond donors were used to prepare six different acidic deep eutectic solvents (DES). The lignin was fractionated from COS by microwave -assisted method using acidic deep eutectic solvents, and lignin nanoparticles (LNPs) were further fabricated by self -assembly strategy. The structural characteristics of lignin and LNPs were analyzed and compared. The results demonstrated that ATMAC-LA pretreatment exhibited the highest delignification of 81.41% and cellulose retention of 95.1%. The molecular weight of lignin extracted from ChClbased DES was lower than those obtained by ATMAC-based DES when using identical hydrogen bond donors. The smallest average particle size (203.07 nm) of LNPs was obtained by ATMAC-AA pretreatment. In addition, ATMAC-LA exhibited the highest interaction energy of 56.1 kcal/mol and stronger electrostatic potential (- 46.72-54.58 kcal/mol), which elucidated its high delignification efficiency. ATMAC-LA DES exhibited high selectivity for lignin dissolution, and LNPs with smaller particle size and excellent stability could be fabricated. This work provides an efficient method to fractionate lignin from COS at 150 celcius for 15 min, and contributing to extend the opportunities of lignin valorization into bio-based materials.
摘要：
为提高马铃薯挤压重组米品质, 选用单甘酯、海藻酸钠和瓜尔豆胶作为品质改良剂, 以马铃薯挤压重组米综合评分为评价指标, 通过单因素试验和正交试验优化得到马铃薯挤压重组米品质改良剂配方。结果表明: 3种改良剂对马铃薯挤压重组米品质影响的大小顺序为: 瓜尔豆胶>单甘酯>海藻酸钠; 最佳品质改良剂配方为: 单甘酯添加量0.3%, 海藻酸钠添加量0.4%, 瓜尔豆胶添加量0.4%。此时马铃薯挤压重组米综合评分可达85.97, 明显高于对照样品的综合评分72.80, 说明此品质改良剂能够明显提高马铃薯挤压重组米的品质。 In order to improve the quality of restructured potato rice, monostearin, sodium alginates and guar gums were chosen as quality improvers. The comprehensive score was used as index to optimize quality improver formula by single factor experiment and orthogonal experiment. The results indicated that the degree of effects on quality of restructured potato rice were guar gum > monostearin > sodium alginate. The optimum formula was monostearin 0.3%, sodium alginate 0.4%, guar gum 0.4%. Under such conditions, the comprehensive score increased from 72.80 to 85.97.It showed that the formula has obvious effect on the quality of restructured potato rice.
摘要：
A novel lysosome-targetable phthalimide fluorescent probe was designed for detecting palladium based on ESIPT for signal transduction. The fluorescent probe conjugating with allylcarbamate displayed weak fluorescent due to the ESIPT process hinder by allylcarbamate. But with the addition of palladium, the ESIPT emission was recovery though the palladium-catalyzed deallylation reaction and the fluorescence intensity exhibited 40-fold enhancement at 511 nm. In addition, the probe showed excellent selectivity, high sensitivity, fast responds and low limit detection for palladium with a larger Stoke-shift. Moreover, the targetable probe was also successfully applied for detecting palladium in lysosomes of living cells. Hence, the probe though ESIPT modulation is a promising for monitoring palladium in practical samples. (C) 2018 Published by Elsevier B.V.
期刊：
Sensors and Actuators B-Chemical,2018年255(Pt.1):42-48 ISSN：0925-4005
通讯作者：
Zhang, Xiangyang;Zhang, Youyu
作者机构：
[Shen, Youming; Zhang, Xiangyang; Chen, Yuandao; Jin, Junling; Zhang, Chunxiang] Hunan Univ Arts & Sci, Coll Chem & Mat Engn, Hunan Prov Cooperat Innovat Ctr Construct & Dev D, Changde 415000, Peoples R China.;[Shen, Youming; Zhang, Youyu; Wu, Yanyang; Li, Haitao] Hunan Normal Univ, Coll Chem & Chem Engn, Minist Educ, Key Lab Chem Biol & Tradit Chinese Med Res, Changsha 410081, Hunan, Peoples R China.;[Wu, Yanyang] Hunan Agr Univ, Food Sci & Technol Coll, Changsha 410000, Hunan, Peoples R China.
通讯机构：
[Zhang, Xiangyang; Zhang, Youyu] H;Hunan Univ Arts & Sci, Coll Chem & Mat Engn, Hunan Prov Cooperat Innovat Ctr Construct & Dev D, Changde 415000, Peoples R China.;Hunan Normal Univ, Coll Chem & Chem Engn, Minist Educ, Key Lab Chem Biol & Tradit Chinese Med Res, Changsha 410081, Hunan, Peoples R China.
关键词：
Colorimetric and ratiometric fluorescent;sensor;Mitochondria-targeted;Hydrogen peroxide;Living cell imaging
摘要：
A novel mitochondria-targeted fluorescent probe compound 1 for H2O2 has constructed based on a coumarin as the fluorophore and a boronate moiety as the reaction site, which showed colorimetric and ratiometric fluorescence dual response to H2O2. This probe displayed a large blue-shifted in emission wavelength (105 nm) with two well-resolved emission bands toward hydrogen peroxide. The compound 1 can be quantitative, good selective and sensitive recognition to H2O2 with low detection limit (10 nM). The sensing mechanism was confirmed by H NMR and HRMS spectroscopy. The mechanism regarding the optical responses of the compound 1 toward H2O2 was also determined by density function theory (DFT) calculations. Moreover, the probe could be used for determining H2O2 in living cells by ratiometric fluorescence imaging with excellent mitochondrial targeting. (C) 2017 Published by Elsevier B.V.
通讯机构：
Hunan Provincial Key Laboratory of Food Science and Biotechnology, College of Food Science and Technology, Hunan Agricultural University, Changsha, China
摘要：
Chlorophylls and chlorophyll–protein complexes determine the color and other sensory properties of spinach. This study investigated the effects of high hydrostatic pressure (HHP) (100, 250, and 500 MPa for 5 min) treatments on structure, chlorophylls and soluble protein contents, protein peptide and fatty acid compositions, chlorophylls absorption spectra, emission, and excitation fluorescence spectra of thylakoid membrane in spinach, in order to better understand the changes in chlorophylls and chlorophyll–protein complexes under HHP. The result showed that HHP-treated samples showed a compact and stacked structure of thylakoid membrane in spinach. For the components of thylakoid membrane, both of chlorophylls and soluble protein contents were significantly (p<0.05) reserved by HHP treatments. The composition of proteins, peptides, and fatty acids was close to untreated samples, revealing higher stability under HHP. In addition, chlorophylls emission and excitation fluorescence spectra capacities of thylakoid membrane were better maintained under HHP treatments compared with thermal treatment, indicating higher light-harvesting and excitation efficiencies of Photosystem II (PS II). As the key functional component of thylakoid membrane, retention of PS II reflected the stability of thylakoid membrane functions under HHP. Hence, chlorophylls and chlorophyll–protein complexes were effectively sustained under HHP treatments, providing new opportunities to preserve the color quality of green vegetables.
摘要：
以马铃薯原淀粉为对照,研究了纤维素酶-压热法制备的马铃薯抗性淀粉的理化性质。结果表明,马铃薯原淀粉颗粒呈椭球形,表面光滑;而抗性淀粉的颗粒状结构消失,形成了连续的致密结构,表面不再光滑。红外光谱分析表明,抗性淀粉分子中未出现新的基团,只较原淀粉形成了更多的氢键。马铃薯原淀粉的分子晶型为A型,整体结晶度为22.82%;抗性淀粉的分子晶型为B型,整体结晶度为29.64%。马铃薯抗性淀粉的溶解度、透明度远远低于原淀粉;膨润度、持水性优于原淀粉。抗性淀粉的沉降速度较快,沉降性比原淀粉强。原淀粉糊化温度为65.8℃,峰值黏度可达到10 770 m Pa·s;而抗性淀粉其糊化温度高于95℃。
