 |
 |
 |
 |
 |
 |
||
 |
 |
 |
 |
 |
| 2 | 1/1 | 返回列表 |
| 查看: 1228 | 回復: 1 | |||
[交流]
所有金幣拜求論文摘要英文翻譯
|
|
甜味是食品科學的一個基本問題，甜味感官特征的評價一直依賴于人的感官品評。由于品評人員個體、性別及閱歷等生理和心理的差異，對味覺客觀、真實感受的表達存在著很大的制約性。而且，基于實驗條件的限制和甜味感覺的特殊性，人們至今沒有完整理解甜味分子的感受機理。而在甜味抑制劑研究方面，雖然人們對甜味抑制劑作用位點達成了共識，但有關(guān)甜味抑制物質(zhì)起作用的機制是競爭性的還是非競爭性的，仍然沒有統(tǒng)一的結(jié)論。 本課題組前期以富勒醇C60(OH)18作為人工甜味化學受體模型，運用等溫滴定量熱（ITC）方法探索甜味識別的熱力學，研究結(jié)果表明富勒醇對人工甜味劑、天然甜味劑都具有較好的識別效果，其作為模型化合物研究甜味機理具有可行性。本論文進一步運用感官品評、ITC、核磁共振（NMR）和分子模擬（MS）等多種實驗手段共同研究人工甜味受體模型與甜味抑制劑，甜味異構(gòu)體、甜味增強劑的識別作用，以期獲得甜味機理方面更多的信息。 本課題研究的內(nèi)容有： （1）人工甜味化學受體模型與甜味抑制劑作用的研究 采用甜味抑制劑（HPMP）和十四種常用甜味劑，通過前期建立的人工甜味受體模型ITC滴定模式，獲得抑制過程中熱力學參數(shù)，實驗結(jié)果表明富勒醇優(yōu)先自發(fā)識別HPMP，疏水作用力在識別過程中起著重要作用，HPMP和甜味劑同富勒醇的結(jié)合具有競爭性。 同時采用“快速作用-有無法”的品評模式進行HPMP感官實驗，通過比較加入甜味抑制劑前后甜味劑察覺閾值，發(fā)現(xiàn)HPMP對不同結(jié)構(gòu)甜味劑的抑制效果不同，離子對其作用無明顯影響，抑制效果可以用Ik（甜味抑制度）量化表示。 比較富勒醇識別過程中熱力學參數(shù)與Ik，發(fā)現(xiàn)熱力學平衡常數(shù)的比值（K1/K2）與Ik有一定的相關(guān)性，K1/K2比值越大，甜味抑制度Ik越高，由此佐證了甜味抑制機理可能是甜味抑制物質(zhì)競爭與味蕾受體結(jié)合產(chǎn)生的。實驗結(jié)果進一步說明利用人工受體模型研究甜味機理的有效性。 （2）人工甜味受體模型與甜味劑異構(gòu)體作用的研究 通過ITC、NMR和MS等技術(shù)共同研究富勒醇與單糖異構(gòu)體的作用，實驗結(jié)果表明在溶液中多種單糖異構(gòu)體共存的情況下，富勒醇與β型異構(gòu)體結(jié)合更穩(wěn)定，優(yōu)先與之形成氫鍵，此過程中釋放出的能量可以提供α型異構(gòu)分子轉(zhuǎn)化成β型異構(gòu)分子所需的構(gòu)象轉(zhuǎn)化能，打破溶液中原有的變旋平衡，向生成β型異構(gòu)體的方向移動，導致溶液中β型異構(gòu)體比例明顯增加。因此可以推測，單糖分子接近味蕾受體時，可能也引起甜味劑異構(gòu)體的平衡移動，導致異構(gòu)體的比例發(fā)生變化，具體表現(xiàn)為各種糖類異構(gòu)體的甜度差異。 （3）人工甜味化學受體模型與甜味增強劑作用的研究 通過MS手段進行富勒醇分子與甜味增強劑的相互作用的研究，結(jié)果表明甜味增強劑與富勒醇形成氫鍵后，還與甜味分子形成較強氫鍵，這樣就拉近了甜味分子與富勒醇的距離，增強了甜味分子與富勒醇的氫鍵強度，使其更好地與富勒醇進行識別。因此可以推測，甜味增強劑在與味蕾受體結(jié)合的同時，還能與甜味分子形成較強氫鍵，從而增強了甜味分子與味蕾受體的識別作用，實際表現(xiàn)為增強劑單獨使用不產(chǎn)生甜味，但和甜味劑共同使用能有效增強甜感。 （4）不同結(jié)構(gòu)的人工甜味受體模型與甜味劑相互作用的研究 通過分子動力學模擬，對現(xiàn)有人工甜味受體模型C60(OH)18進行結(jié)構(gòu)優(yōu)化，實驗結(jié)果表明富勒醇隨碳數(shù)增加碳球籠體積增大，在理想稀溶液中，分子表面疏水作用力增加，無法更好與甜味分子識別；富勒醇羥基數(shù)的增加會使其與單糖分子的結(jié)合能增加，識別作用更加明顯，但是羥基數(shù)過多會減小分子表面疏水作用力，分子表面的羥基因為距離過近會相互吸引形成分子內(nèi)，增大識別過程中噪音能量，不利于多羥基富勒醇分子與單糖分子的識別作用。因此，結(jié)構(gòu)優(yōu)化結(jié)果表明C60(OH)20更適合作為人工甜味受體模型。 總之，本文在前期研究的基礎(chǔ)上，采用多種實驗手段，進一步利用富勒醇作為人工甜味受體的模型化合物研究了它與甜味劑異構(gòu)體、甜味抑制劑和甜味增強劑的相互作用，在目前人們未能獲得甜味蛋白精細結(jié)構(gòu)之前，研究結(jié)果對于理解甜味識別、甜味抑制機理和甜味增強機理具有一定的意義，同時也豐富了甜味機理研究的仿生化學。 |
回復此樓» 猜你喜歡
271材料工程求調(diào)劑
已經(jīng)有5人回復
-
281求調(diào)劑（0805）
已經(jīng)有16人回復
-
304求調(diào)劑
已經(jīng)有6人回復
-
材料工程專碩調(diào)劑
已經(jīng)有6人回復
-
一志愿天大材料與化工（085600）總分338
已經(jīng)有4人回復
-
085700資源與環(huán)境308求調(diào)劑
已經(jīng)有3人回復
-
求材料調(diào)劑
已經(jīng)有8人回復
-
294求調(diào)劑材料與化工專碩
已經(jīng)有5人回復
-
一志愿華中科技大學，080502，354分求調(diào)劑
已經(jīng)有4人回復
-
一志愿吉林大學材料學碩321求調(diào)劑
已經(jīng)有6人回復
» 搶金幣啦！回帖就可以得到:
-
青島高校2026招生碩士研究生
+5/840
-
持續(xù)創(chuàng)業(yè)者，A8離異男征婚，事業(yè)遇到瓶頸，尋找創(chuàng)業(yè)生活伴侶
+1/484
-
祈福2026國基面上項目
+5/350
-
南京醫(yī)科大學生殖醫(yī)學與子代健康國重實驗室-董飛宏課題組-學術(shù)碩士招生
+1/95
-
散金幣，求好運，祝面上順利！
+2/94
-
專業(yè)技術(shù)開發(fā)及第三方檢測
+1/87
-
物理學 調(diào)劑
+1/85
-
歡迎交流咨詢
+1/37
-
1
+1/35
-
招收專業(yè)代碼08的學碩！
+1/25
-
海南師范大學孫元元老師招生博士，名額1~2個，2026年9月份入學（光電/光熱催化方向）
+1/17
-
醫(yī)學327分專碩調(diào)劑
+1/16
-
【武漢高校】【新能源材料與器件課題組】 招收優(yōu)秀碩士調(diào)劑生�。�！
+5/15
-
新加坡國立大學藥學系化學生物學課題組招PhD
+1/13
-
山東省植物基蛋白技術(shù)創(chuàng)新中心課題組聯(lián)合培養(yǎng)碩士研究生招募啟事
+1/12
-
南京理工大學招收2026級碩士生-張光普博導
+2/10
-
新加坡國立大學藥學系化學生物學課題組招PhD
+1/8
-
26年申博自薦-計算機視覺
+1/7
-
中國科學院過程工程研究所助理研究員（正式職工）和博士后招聘啟事
+1/5
-
深圳大學蔡興科課題組博士后及研究助理招聘
+1/2
木子小木蟲:本版嚴禁軟件翻譯，警告 2010-11-11 11:10:50
| Sweet is a basic problem of food science, the evaluation of the sensory characteristics of sweet taste has been dependent on the sensory evaluation. The evaluation of individual staff, such as gender and experience physical and psychological differences, the objective of the Taste, the expression of true feelings of the existence of significant constraints. Moreover, based on the experimental conditions, the special restrictions and sweet feeling, it has not felt the full understanding of the molecular mechanism of sweet taste. In the sweetness inhibitors, although one site on the sweetness inhibitor reached a consensus, but work on the mechanism of sweet taste inhibitor is competitive or non-competitive, and still no uniform conclusions. Early in our group fullerols C60 (OH) 18 as a chemical receptor model of artificial sweetness, using isothermal titration calorimetry (ITC) method to explore the thermodynamic sweet recognition, the results show that artificial sweeteners fullerenol, natural sweeteners have a good recognition effect, its mechanism of sweetness as a model compound with a feasibility study. The paper further use of sensory evaluation, ITC, nuclear magnetic resonance (NMR) and molecular simulation (MS) and other experimental methods to study with the sweetness receptor model of artificial sweetness inhibitors, isomers sweet, sweet enhancer Recognition, in order to obtain more information mechanism are sweet. The contents of this research are: (1) chemical receptor model of artificial sweetness sweetness sweetness inhibitor effect of inhibitors used (HPMP) and fourteen commonly-used sweeteners, artificial sweetness through the pre-established by the ITC titration model body model, inhibition of the process to obtain the thermodynamic parameters, experimental results show that self-identify priority fullerenol HPMP, hydrophobic interactions in the recognition process plays an important role, HPMP and sweetener with the combination of fullerenol competitive . At the same time a "fast effect - there can not be" tasting mode HPMP sensory experiments, by comparing before and after adding inhibitor sweetener sweetness threshold detection and found that the structure of different sweeteners HPMP the inhibitory effect of different ions on the role of non- significant effect, inhibitory effect can Ik (sweet suppression degree) to quantify said. Comparison Fullerenols thermodynamic parameters of the process of identifying and Ik, found that the ratio of the thermodynamic equilibrium constant (K1/K2) and Ik have some relevance, K1/K2 ratio the greater the degree of sweetness suppression Ik higher, thus supporting the inhibition mechanism may be the sweet sweet taste buds of competition and inhibition of receptor-binding material produced. The results further explanation of the use of artificial sweet taste receptor model the effectiveness of the mechanism. (2) artificial sweeteners sweet receptor models and the role of isomers by ITC, NMR, and MS Fuller and other technologies to study alcohol and the role of monosaccharide isomers, experimental results indicate that a variety of single-solution isomer coexistence of sugar, the Fuller alcohol combined with the β-isomer is more stable, priority with the formation of hydrogen bonds, this process can provide the energy released α-β-isomer molecules into heterogeneous elements conformational transition required to break the Central Plains and some change spin balanced solution to generate β-isomers of direction, leading to β-isomers in solution was significantly increased. Can therefore speculate that a single sugar molecule close to the taste bud receptors may also lead to the equilibrium shift isomers sweeteners, leading to changes in the ratio of isomers, is specifically expressed in a variety of differences between the sweetness of sugar isomers. (3) chemical receptor model of artificial sweetness enhancer and the effect of sweet taste by molecular MS fullerols means interaction with the sweetness enhancer, the results show that the sweetness enhancer and the formation of hydrogen bonds fullerenol later, also with the sweet molecules form strong hydrogen bonds, so sweet closer the distance between alcohol molecules and Fuller, Fuller enhanced sweet alcohol molecules and the hydrogen bond strength, making it better with Fuller alcohol for identification. So you can guess, sweetness enhancers and taste buds in the same receptor, but also strong and sweet molecules form hydrogen bonds, thus increasing the sweet taste receptor molecules and identify the role of taste buds, the actual performance of the enhancer alone does not produce sweet, but the common use, and sweeteners can enhance the sweet feeling. (4) different structures of the human sweet taste receptor model of the interaction with sweetener by molecular dynamics simulation, artificial sweet taste receptor model of the existing C60 (OH) 18 to optimize the structure, experimental results show that fullerenol With the increase in the number of carbon Carbon Cage volume increase, in an ideal dilute solution, the molecular surface hydrophobic interactions increase with the sweetness of molecular recognition can not be better; Fuller hydroxyl increase in the number of single sugar molecules to the binding energy increased recognition is more obvious, but too much will reduce the number of hydroxyl hydrophobic molecular surface, molecular surface hydroxyl groups as too close to be attracted to each other to form molecules, the increase in the noise energy of the recognition process is not conducive to polyhydroxy Fuller alcohol molecules and the role of molecular recognition of monosaccharides. Therefore, the structural optimization results show that the C60 (OH) 20 is more suitable for human sweet taste receptor model. In short, this paper, based on previous studies, using a variety of experimental methods, further use of artificial sweet fullerenol receptor as model compound to study its isomer with the sweeteners, sweetness inhibitors and sweetness enhancers interaction, people are not given in the current fine structure of the sweet protein before, the results for the understanding of sweetness recognition, inhibition mechanism and the sweet sweet enhancement mechanism has a certain significance, but also enrich the mechanism of the biomimetic chemistry sweet . |
2樓2010-11-10 17:36:01
相關(guān)版塊跳轉(zhuǎn)
我要訂閱樓主 雯娶星 的主題更新
| 2 | 1/1 | 返回列表 |
| 最具人氣熱帖推薦 [查看全部] | 作者 | 回/看 | 最后發(fā)表 | |
|---|---|---|---|---|
|
[考研] 一志愿吉林大學材料學碩321求調(diào)劑 +4 | Ymlll 2026-03-18 | 6/300 |
|
|---|---|---|---|---|
|
[考研] 321求調(diào)劑 +3 | 何潤采123 2026-03-18 | 3/150 |
|
|
|
[考研] 085600材料與化工調(diào)劑 324分 +8 | llllkkkhh 2026-03-18 | 8/400 |
|
|
|
[考研] 0703化學調(diào)劑，求各位老師收留 +9 | 秋有木北 2026-03-14 | 9/450 |
|
|
|
[考研] 314求調(diào)劑 +8 | 無懈可擊的巨人 2026-03-12 | 8/400 |
|
|
|
[考研] 085601專碩，總分342求調(diào)劑，地區(qū)不限 +5 | share_joy 2026-03-16 | 5/250 |
|
|
|
[考研] 311求調(diào)劑 +11 | 冬十三 2026-03-15 | 12/600 |
|
|
|
[考研] 0854可跨調(diào)劑，一作一項核心論文五項專利，省、國級證書40+數(shù)一英一287 +8 | 小李0854 2026-03-16 | 8/400 |
|
|
|
[考研] 材料專碩274一志愿陜西師范大學求調(diào)劑 +6 | 薛云鵬 2026-03-13 | 6/300 |
|
|
|
[碩博家園] 湖北工業(yè)大學 生命科學與健康學院-課題組招收2026級食品/生物方向碩士 +3 | 1喜春8 2026-03-17 | 5/250 |
|
|
|
[考研] 283求調(diào)劑 +3 | 聽風就是雨； 2026-03-16 | 3/150 |
|
|
|
[基金申請]
今年的國基金是打分制嗎？
50+3
|
zhanghaozhu 2026-03-14 | 3/150 |
|
|
|
[考研] 304求調(diào)劑 +4 | ahbd 2026-03-14 | 4/200 |
|
|
|
[考研] 一志愿211 0703方向310分求調(diào)劑 +3 | 努力奮斗112 2026-03-15 | 3/150 |
|
|
|
[考研] 0703化學調(diào)劑 290分有科研經(jīng)歷，論文在投 +7 | 膩膩gk 2026-03-14 | 7/350 |
|
|
|
[考研] 266求調(diào)劑 +4 | 學員97LZgn 2026-03-13 | 4/200 |
|
|
|
[考研] 材料與化工（0856）304求B區(qū)調(diào)劑 +6 | 邱gl 2026-03-12 | 7/350 |
|
|
|
[考研] 311求調(diào)劑 +3 | 冬十三 2026-03-13 | 3/150 |
|
|
|
[碩博家園] 085600 260分求調(diào)劑 +3 | 天空還下雨么 2026-03-13 | 5/250 |
|
|
|
[考研] 求調(diào)劑 +3 | 程雨杭 2026-03-12 | 3/150 |
|