食品專業(yè)英語5

1、food englishlesson 3 : amino acids2021-11-152021-11-152contentsexercisestextnew wordsquestionshomework2021-11-152021-11-1531 which nutrients exist in food?protein , carbohydrate,lipids, water, vitamins, minerals dietary fiber (df)answer is :2021-11-152021-11-154carbon2 which elements include in prot

2、ein?hydrogenoxygennitrogenoccasionally:sulphur2021-11-152021-11-155how many kinds of amino acids in protein?how many kinds of essential amino acids in protein? they are ?20 8+12021-11-152021-11-156new words 1. amino- 氨基的氨基的amino group 氨基氨基 -nh2 amino nitrogen 氨基態(tài)氮氨基態(tài)氮amino acid 2021-11-152021-11-157

3、-yl 基l acyl ?；鵯 acetyl 乙?；鵯 methyl 甲基l ethyl 乙基l propyl 丙基l carboxyl 羧基l carbonyl 羰基 u group 基團(tuán)2021-11-152021-11-158exersicesvaminoacylase 氨基?；?vpeptidase 肽酶vcarboxymethyl- 羧甲基vethyl alcohol 乙醇vtricarboxylic acid cycle 2021-11-152021-11-159meta- 變化, 代謝umetabolic adj. 作用的,新陳代謝的umetabolic rate 代謝率ume

4、tabolic activity 代謝能力umetabolic balance 代謝平衡umetabolite n. 代謝(產(chǎn))物umetabolism n. 新陳代謝umetabolize v. 使代謝,使同化umetabolizable adj. 可代謝的2021-11-152021-11-15102)new wordslprecursor n. 前體；先驅(qū)lgenus n. 種類、屬lgenera pl.lisolates n. 種群 lmutant n. 突變異種lsubstrate n. 底物 ant. 終產(chǎn)物： end products2021-11-152021-11-1511l

5、excrete vt. 排泄；分泌lfeedback 反饋 lfeedback inhibition 反饋抑制2021-11-152021-11-1512amino acid neutral nonpolaraminoacidsglycineglaisi:nglygalaninel ni:nalaavalinevali:nvalvleucinelu:si:n, -sinleulisoleucineaisulu:si:nileiphenylalanine?fenllni:npheptriptfntrywmethioninemeai ni:nmetmcysteinesistii:ncyscprol

6、inepruli:nprop2021-11-152021-11-1513neutral polaraminoacidsserineseri:nser sthreonine ri: ni:nthr ttyrosine tirsi:ntyryasparaginesprdi:nasn nglutamine glu:tmi:ngln qacidica.aaspartic acidasp dglutamic acidglu ebasica.alysine laisi:nlys larginine a:dini(:)narg rhistidine histidi:n, -dinhish2021-11-15

7、2021-11-1514 are produced using a range of technologies including , , extraction of protein hydrolysates and chemical synthesis.text2021-11-152021-11-1515text2021-11-152021-11-1516some phrasesvflavourflavour enhancer enhancer v風(fēng)味加強(qiáng)劑vbaking antioxidantbaking antioxidantv焙烤抗氧化劑vsweetener componentswee

8、tener componentv甜味成分vfeed additivefeed additivev食品添加劑2021-11-152021-11-1517important amino acids with non-important amino acids with non-food applications include l-food applications include l-argininearginine, l-glutamine, l- , l-glutamine, l- histidinehistidine, l-, l-leucineleucine, l-, l-phenyla

9、lanine, l-tyrosine and phenylalanine, l-tyrosine and l-l-valinevaline. .text2021-11-152021-11-1518question for first paragraph1.direct fermentation 2.biotransformation of precursors using cells or enzymes 3.extraction of protein hydrolysates4.chemical synthesis2021-11-152021-11-1519while fermentatio

10、n or biotransformation processes have been developed for production of all amino acids except ., not all of these processes are commercially viable.text在大量的生產(chǎn)中是可行的2021-11-152021-11-1520.are produced by purification of protein hydrolysatestextpurification 純化purifier 純化裝置purify v. 純化purificant 凈化劑2021

11、-11-152021-11-1521chemical synthesis is more economical for production of optically-inactive racemic mixture of d-and l-isomers, textoptical : 光學(xué)的光學(xué)的optically-inactive：無光學(xué)活性的無光學(xué)活性的iso- 等,同,異.(p126)isomer 同分異構(gòu)體2021-11-152021-11-1522processes involving amino acylase enzymes may be used to resolve thes

12、e racemic mixtures.text氨基?；赴被；?021-11-152021-11-1523vin this paragraph each production in this paragraph each production method had be made a brief method had be made a brief introductionintroduction.v which method according to text may produce most types of amino acids? fermentation or biotransf

13、ormation 2021-11-152021-11-1524the last paragraphthe last paragraph2021-11-152021-11-1525because of cell metabolic regulatory mechanisms, particularly end-product repression and inhibition, substantial levels of amino acids are rarely excreted by wild-type isolates.text代謝調(diào)節(jié)機(jī)制代謝調(diào)節(jié)機(jī)制野生種群野生種群終產(chǎn)物的阻終產(chǎn)物的阻

14、遏和抑制遏和抑制實(shí)際需要量實(shí)際需要量2021-11-152021-11-1526auxotrophic mutants, which lack the enzyme needed to form the regulatory effector metabolite (often the end product), may accumulate and excrete the metabolic intermediate which is the substrate for the eliminated enzyme效應(yīng)物效應(yīng)物代謝中間物代謝中間物底物底物營養(yǎng)缺陷型突變體營養(yǎng)缺陷型突變體2021

15、-11-152021-11-1527end-product inhibition by the amino acid product of an unbranched biosynthetic pathway the development of regulatory mutants, (having an altered feedback-insensitive key enzyme, thus allowing accumulation of the particular amino acid).調(diào)節(jié)型突變體調(diào)節(jié)型突變體關(guān)鍵酶關(guān)鍵酶2021-11-152021-11-1528lessent

16、ial amino acids (eaa) 必需氨基酸ldispensable (nonessential ) amino acids (daa, neaa) 非必需氨基酸lconditionally dispensable amino acids 條件非必需氨基酸lcysteine 半胱氨酸methionine ltyrosine 酪氨酸 phenylalanine ltaurine 牛磺酸supplements2021-11-152021-11-1529indispensable (essential) amino acids (idaa, eaa) 必需氨基酸必需氨基酸1. isoleucine, ile 異亮氨酸異亮氨酸2. lysine, lys 賴氨酸賴氨酸3. methionine, met 蛋氨酸蛋氨酸,甲硫氨酸甲硫氨酸4. valine, val 纈氨酸纈氨