食品专业英语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 氨基态氮氨基态氮amino acid 2021-11-152021-11-157

3、-yl 基l acyl 酰基l acetyl 乙酰基l methyl 甲基l ethyl 乙基l propyl 丙基l carboxyl 羧基l carbonyl 羰基 u group 基团2021-11-152021-11-158exersicesvaminoacylase 氨基酰化酶 vpeptidase 肽酶vcarboxymethyl- 羧甲基vethyl alcohol 乙醇vtricarboxylic acid cycle 2021-11-152021-11-159meta- 变化, 代谢umetabolic adj. 作用的,新陈代谢的umetabolic rate 代谢率ume

4、tabolic activity 代谢能力umetabolic balance 代谢平衡umetabolite n. 代谢(产)物umetabolism n. 新陈代谢umetabolize v. 使代谢,使同化umetabolizable adj. 可代谢的2021-11-152021-11-15102)new wordslprecursor n. 前体；先驱lgenus n. 种类、属lgenera pl.lisolates n. 种群 lmutant n. 突变异种lsubstrate n. 底物 ant. 终产物： end products2021-11-152021-11-1511l

5、excrete vt. 排泄；分泌lfeedback 反馈 lfeedback inhibition 反馈抑制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风味加强剂vbaking antioxidantbaking antioxidantv焙烤抗氧化剂vsweetener componentswee

8、tener componentv甜味成分vfeed additivefeed additivev食品添加剂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在大量的生产中是可行的2021-11-152021-11-1520.are produced by purification of protein hydrolysatestextpurification 纯化purifier 纯化装置purify v. 纯化purificant 净化剂2021

11、-11-152021-11-1521chemical synthesis is more economical for production of optically-inactive racemic mixture of d-and l-isomers, textoptical : 光学的光学的optically-inactive：无光学活性的无光学活性的iso- 等,同,异.(p126)isomer 同分异构体2021-11-152021-11-1522processes involving amino acylase enzymes may be used to resolve thes

12、e racemic mixtures.text氨基酰化酶氨基酰化酶2021-11-152021-11-1523vin 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代谢调节机制代谢调节机制野生种群野生种群终产物的阻终产物的阻

14、遏和抑制遏和抑制实际需要量实际需要量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效应物效应物代谢中间物代谢中间物底物底物营养缺陷型突变体营养缺陷型突变体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).调节型突变体调节型突变体关键酶关键酶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 条件非必需氨基酸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 异亮氨酸异亮氨酸2. lysine, lys 赖氨酸赖氨酸3. methionine, met 蛋氨酸蛋氨酸,甲硫氨酸甲硫氨酸4. valine, val 缬氨酸缬氨