營養(yǎng)學(xué)基礎(chǔ)2課件

SECTION5MINERALS（礦物質(zhì)）

一、

Introduction

Elements（元素）inhumanbody

TotalelementsInhumanbodyisover80.Essentialelementsinhumanbodyover20,mostofthem(about20)aremineralelements

Microelements:Fe,Zn,Se,I,Cu,Co,Cr,F,Mn,MineralsMo,Si,Ni,B,V.Macroelements:Ca,P,Na,K,Mg,S,Cl.Functionofmineralsinbody1.Compositionofhumanbody.2.MaintainthepHandosmoticpressure(滲透壓)ofbodyliquids.3.Regulatingtheexcitingofnerveandmuscle.4.Componentsofprostheticgroup(輔基),hormone,vitamin,protein,nucleicacid,andactivator（激活劑）ofenzyme.5.Theothers二、鈣（Calcium）

1.DistributionofCalciuminhumanbody

Cainthebody:850-1200g1.5%-2.0%ofbodyweightBone,teeth,99%:

Hydroxyapatite（羥磷灰石）amorphousCa（未定形鈣）

Combinedform,0.5%:

combinedwithproteinandcitricacid（

檸檬酸）Ion,0.5%：MiscibleCaPool（混溶鈣池）Inblood,extra-cellularfluid,softtissue,andexchangeable.2).Regulatingneuromuscular(神經(jīng)肌肉)

excitability,maintaining

transmissionofnerveimpulses

(神經(jīng)沖動)andheartbeats.

(3)Influencingenzymereaction:

Succinodehydrogenase(琥珀酸

脫氫酶).Lipase(脂肪酶),

ATPase(三磷酸腺苷酶),

proteinase(蛋白酶),

(4)Others:hormonesecretion,blood

coagulation(凝結(jié)),acid-base

balance,normalcolloid(膠體).

3.AbsorptionandMetabolism

1)Mechanismofabsorption:

Position:inthesmallintestine

Transcellular(跨細胞):

saturable(可飽和的)(active)transferthatinvolvesacalcium-bidingprotein,

calbindin(鈣結(jié)合蛋白).

Paracellular(同細胞水平):anonsaturable

(diffusional

擴散)transferthatisalinear(一維的)functionofthecalciumcontentofthechyme(食糜).2)Affectingfactors

Age

children:75%0fingestedCa;>40%offoodCaadults:30%-60%;20%~>70y1/3ofadult’s;<15%~

Sex

male>femalePhysiologicalsituationpregnancyandbreast-feed>others

BodyCaconc.

Dietaryfactors

increasingCaabsorption:

Vit.D,Lactose,Someaminoacids:

Arginine(精氨酸),lysine(賴氨酸)

decreasingCaabsorption:

phytate(植酸鹽),oxalate(草酸鹽),fibre,fattyacid,alcohol;thyroidhormone(甲狀腺素),cortisol(皮質(zhì)醇),andantibiotics:penicillin,chloramphenical(氯霉素),neomycin(新霉素)膳食成分對鈣吸收利用的影響提高吸收利用降低吸收利用無作用乳糖植酸鹽磷某些氨基酸膳食纖維蛋白質(zhì)VitD草酸鹽VitC脂肪（脂肪瀉時）檸檬酸乙醇果膠Vit.Dandparathyin(甲狀旁腺素):renalreabsorption↑Calcitonin(降血鈣素):inhibitingbonelossandincreasingurineCa.Calmodulin(鈣調(diào)節(jié)素):regulatingtheCainthecell.Biologiccontrolsystemforhomeostasis(體內(nèi)平衡)ofCa.ECF:Extracellularfluid

CalciumbalanceOnaverage,inatypicaladultapproximately1gofelementalcalcium(Ca2+)isingestedperday.Ofthis,about200mg/daywillbeabsorbedand800mg/dayexcreted.Approximately1kgof(Ca2+)isstoredinboneandabout500mg/dayisreleasedbyresorptionordepositedduringboneformation.Ofthe10gof(Ca2+)filteredthroughthekidneyperdayonlyabout200mgappearsintheurine,theremainderbeingreabsorbed.4.DRIsofCa

EstimationofDRIs（膳食參考攝入量）

Infants:meanintakeofbreastmilk(母乳)Others:Cabalancetest(平衡試驗)Directmeasure(2)DRIs(mg/d)

y:0~0.5~1~4~11~18~50~AI:30040060080010008001000Y:pregnantwomenwetnurse（乳母）AI:1000(中期)1200(晚期)1200UL(tolerableupperintakelevel,):2000mgNOAEL:1500mg常用食物中的鈣含量（mg/100g食部）名稱含鈣量名稱含鈣量名稱含鈣量人奶34海帶(干)1177蠶豆93牛奶120發(fā)菜767腐竹280奶酪590銀耳380花生仁67蛋黃134木耳357杏仁(生)140標準粉24紫菜343西瓜子(炒)237標準米10大豆367南瓜子(炒)235蝦皮2000豆腐絲284核桃仁119豬肉(瘦)11豆腐240~277小白菜93~163牛肉(瘦)6青豆240大白菜61羊肉(瘦)13豇豆100油菜140雞肉(瘦)11豌豆84韭菜105三、Iron(鐵)

1.ironinBodyBodyiron(4-5g)Hemoglobin(血紅蛋白)(60%-75%)Myoglobin(肌紅蛋白)(3%)Hemeenzymes(含鐵酶)Cytochromes(細胞色素)Cytochromeoxidase(細胞色素氧化

酶)Peroxidase(過氧化物酶)Catalase(過氧化氫酶)Ferritin(鐵蛋白)Hemosiderin(含鐵血黃素)

4mgastransportironboundtotransferrin(運鐵蛋白)intheplasma.Nofreeionofironinthebody.FunctionalFe(75%)StorageFe(25%)ironinBody3.AbsorptionandMetabolism

AbsorptionFe3+Fe2+FoodFeduodenumJejunum空Ileum回colonPlasmairon(~4mg)Fe3++transferrin(35~40mgturnedover/d)StorageFe300~400mgR-Esystem,liver,spleen,bonemarrowBonemarrow20~25mg/dhemoglosinHemoglobin

catabolismUrine,sweet,bile,feces(0.5~1mg/d)TransportationUtilizationandconservationStorageHemorrhageRBClostinurine,menstrualloss0.3~1mg/dAllbodycellDeathcellsDesquamation(脫落)ofcells20~25mgExcretion

outlineofironmetabolisminadultIronabsorptionandmetabolism

Humanunabletoexcreteexcessiron.Ironbalancephysiologicallyregulatedbycontrolofabsorption1)Absorptionofnonhemeiron(非血紅素鐵)FoodFeGastricjuicepH<4Fe3+Fe2+(Fe3+)Fe3+,Fe2+orchelateVitCVitC,sugar,AAstomachImpairedabsin(achlorhydriaand)gastrectomyapoferritinferritinMucosalcelltransferrin

β

1-globulinFe2+desquamationIngestionDuodeum(majorplace)pH>=7Solubilityof(Fe2+>Fe3+)AbsorptionCryptatthebaseofvilliFeTransferrindesquamationvilliBloodaccordingtoneedFe2+factorsofincreasingabsorption

irondosage

vit.C,B2;aminoacids:cysteine(半胱氨酸)MFPfactor(meatfishpoultryfactor，肉魚禽因子)Ca,Fehelpeachothertodiminishtheinhibitors；Zn,Fehavecompetitiveabsorption.2)absorptionofhemeiron(血紅素鐵)

hemeironenzymeduodenumcellblood(transferring)Theabsorptionofhemeironisnotinfluencedbyinhibitorswhichdecreasetheabsorptionofnonhemeiron.

3)absorptionrateofironinthefoods

rice1%corn3%blackbean3%lettuce4%flour5%soybean6%fish11%

hemoglobin15%

mustle,liver22%

3)TheprocessassessmentofIDA

1ststageirondecrease(ID):storedironexhaustion,serumferritin↓.2ndstage

Iron-deficiencyinerythrocytosis(紅細胞生成缺鐵期):serumFeandferritin↓,iron-bidingcapacity↑(saturationoftransferrin↓,運鐵蛋白飽和度),cons.offreeerythrocyteprotoporphyrin(FEP)(游離原撲啉)↑

3rdstage

IDA:hemoglobinandhematocrite(紅細胞壓積)valuesdecline.4)Deficiencysymptoms

Immunesystem:

ReducedresistancetoinfectionNervous/Muscularsystems

Reducedworkproductivity,tolerancetowork;Reducedphysicalfitness(健康):weakness,fatigue(疲勞);Impairedcognitivefunction（損害認識功能）(children);Reducedlearningability;Increaseddistractibility(注意力分散);Impairedvisualdiscrimination(識別力);Impairedreactivityandcoordination(協(xié)調(diào)性)

(infants).

Skin

Itching(癢);palenailbed(指甲床)andeyemembranes;

palmcreases(掌心起皺);concavenails(凹面指甲);impaired

woundhealing(愈合).

GeneralReducedresistancetocold,inabilitytoregulatebodytemperature,pica(clayeating,iceeating)（異食癖）

Liketheskin,thefingernailsareareflectionofaperson'sstateofhealth.Lowlevelsofzincandironaswellasthyroidproblemscancausebrittlenails.

Reticulocytes：網(wǎng)狀細胞

Inthepresenceofsomeanemias,thebodyincreasesproductionofredbloodcells(RBCs),andsendsthesecellsintothebloodstreambeforetheyaremature.Theseslightlyimmaturecellsarecalledreticulocytes,andarecharacterizedbyanetworkoffilamentsandgranules.Reticulocytesnormallymakeup1%ofthetotalRBCcount,butmayexceedlevelsof4%whencompensatingforanemia.

Checkingforanemia(irondeficiency),whichcanbeeasilytreatedwithironsupplements.Anemiacancauselowenergyandfatigue,andcanleadtofatalhaemorrhaginginwomenduringchildbirth.

Pakistan5.DRIs

Men:15mg/dWomen:20mg/dPregnancy:25-35mg/dWetnurse:25mg/d

FesupplementinUSA6.Foodsource

常用食物中的鐵含量(mg/100g食部)食物含鐵量食物含鐵量食物含鐵量稻米2.3黑木耳(干)97.4芹菜0.8標準粉3.5豬肉(瘦)3.0打油菜7.0小米5.1豬肝22.6大白菜4.4玉米(鮮)1.1雞肝8.2菠菜2.5大豆8.2雞蛋2.0干紅棗1.6紅小豆7.4蝦米11.0葡萄干0.4綠豆6.5海帶(干)4.7核桃仁3.5芝麻醬58.0帶魚1.2桂圓44.0四、碘（Iodine）tetraiodothyronine(T4),16.2%(甲狀腺素)

triiodothyronine(T3),7.6%(三碘甲狀腺原氨酸)thyroidiodine

(8mg)diiodothyronine(DIT),33.4%(二碘酪氨酸)

monoiodothyronine(MIT),32.7%(一碘酪氨酸)

others

Inblood:protein-bindingiodine(PBI),30-60μg/L1.Iodineinthebody(20-50mg)

StructureofT4andT3regulatingoxidationreactionsincellsandenergymetabolism.Regulatingproteinsynthesisbylinkingtotheprocessesofgeneticcontrolinthenucleus.Promotingthesynthesisofcholesterol,intestinalabsorptionofcarbohydrateandconversionofcarotenetoVitA.Regulatingthemetabolismofwaterandelectrolyte.Influencingthegrowthanddevelopment,andmentaldevelopment.(15%mentalretardationinIDareainchina)2.Functionofiodineinbody

colloidTG:thyroglobulin甲狀腺球蛋白3.absorptionandmetabolism

ThyroidglandTGT4T3DITMIT(d

)

(c)T4T3Dietaryiodine肝中合成

葡萄糖酸酯或硫酸酯Fecaliodine10%I-T4bound/freeT3T3T4EffectUrinaryiodine90%SweetandmilkTargetcells(g)bile(a)(b)(e)(f)(h)a:absorptiondietaryiodineisconvertedtoinorganicform(iodine)andrapidlyabsorbedfromthegastrointestinaltract.b,c:circulatingiodineisetherexcretedintotheurineortakenupbythethyroidgland.d,e:thepathwayofT3,T4synthesis.f:secretionofT4andT3intotheblood.g:someofT4isconvertedtoT3andsomeexcretedintothebile.h:tissuesconvertT4toT3andsomeofT3isreturnedtothecirculatinginmanytissues.4.iodinedeficiencyIDD

Adults:goiter（甲狀腺腫）Teenagers:influencingrowth,developmentofbodyandmental.Infants:dementia（癡呆）Supplementofiodide:iodizedsaltKI:1:100000KIO3:1:20000~500005.effectsofexcessiodineiodinegoiter

6.DRIs

Adults150ug/dPregnancy175ug/dWetnurse200ug/dUL850ug/d

7.Dietarysource:seafoods

kelp(海帶)24mg/100g，seaslug（海參）0.6mg/100g，mussel(淡菜)1mg/100g，laver(紫菜)1.8mg/100g

五、鋅（Zinc）

1.

zincinthebody

(2-3g)

foundinallhumantissues(10-200ug/g)Moreinliver,spleen,heart,muscle,bone,eye,andskinblood(900ug/100ml)prostate(前列腺)prostaticsecretionsSpermatozoa（精液）

2.Functionsandzincdeficiency

Essentialconstituentofover100enzymes,ineachofthe6majorenzymecategories:oxidoreductase,transferase,hydrolase(水解)，lyase（裂合）,isomerase（異構(gòu)）andligase（連接）.(2)Influencinggrowth,developmentandsexualsystem.involvingthesynthesisofDNA,RNAprotein(anorexia厭食，failuretogrow,testicularatrophy睪丸萎縮,skinlesions)(3)Havingnormalappetite.(4)PromotingmetabolismofVitA.(5)Maintainingthereproductionofimmunecells.(6)Involvinginneoplastic（瘤的）processes.

2.Functionsandzincdeficiency

Zincfinger

3.Metabolism(shorten)

4.DeficiencyandToxicity5.DRIsanddietarysource

1)DRIs:

1-9y:10mg/d>10y:15mg/dpregnantandwetnurse:20mg/d2)Dietarysource:seafoodsandmeats.

六、硒（Selenium）1.SeinthebodyBodysize(14-20mg)Invariousamountsinalltissuesofthebodyexceptfat

thehighestconcentrationisinliver,heart,kidneyandspleen

bloodSeis0.22ug/ml2.FunctionandSedeficiency

1).Aconstituentofglutathioneperoxidase(GSH-Px),antioxidantandanticancer.2).Detoxification:heavymetals,AFB1.3).Anticarcinogeniceffect:skin,liver,colon,breast,etal.4).Enhancementofhumoral,cell-mediatedandnonspecificimmunity.5).MaintainheartandcardiovascularstructureandfunctionKeshan.

6).Keepingnormalgrowth:impairmentofgrowth,sparse(稀少)hair,cataracts(白內(nèi)障),etal.7).Reducingfreeradicalreaction（自由基反應(yīng)）andextendinglifespan.IncidenceofCancerinPlaceboandSeTreatedSubjects

3.Toxicity:

gastrointestionaldisturbances,badteeth,yellowskin,cardiorenaldisease,lossofhairandnails,nervoussystemdisordersetal.4.DRIs:50ug/d

5.foodsource:

animalfoodandseafood.

Secontentoffooddependsonthesoilinwhichthefoodwasgrown.Section6Vitamins

Preface

1.Commonproperties

Distributedinnaturalfoodstuffsbutdistinctfromthemaincomponentsoffood(proteins,etal)(quantity,energy,componentofbody).Eessentialforbodymetabolism(coenzyme,orprostheticgroup輔基)inminutequantitiesandabsenceofanyoneofwhichcausesacorrespondingspecificdeficiencydisease.CannotbesynthesizedinthebodyexceptVitD.2.Classification:

(1)theorderofdiscovery:A,B,C,D……(2)function:ascorbicacid(3)chemicalconstruction:popular(local)name:riboflavin……(4)solubility:

water-soluble:Bs,C—excessesareexcretedintheurine

fat-soluble:A,D—largeamountaretoxic.3.Deficiencyofvitamins(1)Cause:

deficientintakesproblemofabsorptionincreaseinrequirement(2)Deficiency:

criticaldeficiency:diseasemarginaldeficiency:influencehealthwithoutsymptoms一、VitA

retinal(A1)

s-dehydroretinal(A2)retinolβ-carotene

1.structuresandproperties:

structureA1A2(biopotencyofA2is40%thatofA1)Transconfiguration

Cisconfiguration

β-carotene(provitaminA)

α-carotene

γ-carotenesolubility:solubleinfatsandalltheusualorganicsolvents,insolubleinwater.Oxidation:beoxidizedbylight,airandoxidantsuchasMnO2(Manganesedioxide).Isomerization(異構(gòu)化)：retinolisisomerizedbylightStability:sensitivetowardacidsbutstabletobase.Colorreaction:retinalanditsestershaveayellowish-greenfluorescence(熒光)。

Acidreagentsgivebluecolororpurple(sulfuricacid)reactionwithVit.APropertiesofVit.A

2.Metabolism

absorption:

β-caroteneretinalsmallintestine(水解)1/3(fat,bileacid)retinylesterupperintestineretinolmucosalcellwallEsterifiedchylomicronmucosalcell(水解)（還原）?fromβ-carotenemucosalcell(2)Transportandstorageretinylesterslymphaticsystembloodscreamstorageliver(90%)KidneyLung,eyefreeretinalbloodscreamTissueformetabolicrequirement水解chylomicron

ThebloodlevelofVit.Aisindependentoftheliverreserve.RetinolistransportedinplasmainassociationwithaspecifictransportProteinRBP:Vit.AlevelinplasmisproportionaltothelevelofRBP.(3).ExcretionVit.AInliverVit.AGlucaronides(葡萄糖苷酸)blieReabsorbedExcretedwithfecesliverVit.AIntissuesMethylatedmetabolitesurine3.Function

invision:GeorgeWaldwasawardedtheNobelPrizeformedicinein1967forhisdiscoveryoftheroleofVitAinthevisualsystem.Retinal11-cisform+protein+ospinIodopsin(藍)Rhodopsin（紅）HighlightDimlightAll-transretinal+proteinProducinganervousexitationbrainVisualsensationsSomeofalltrans-retinalDarkadaptation(2)Effectoncellmembrance:regulating

membrancestructureandfunctionby

influencingthebiosynthesisofglycoproteinbecauseVitAisheadedforcarryingmono-oroligosacchrideunitstoacceptorsite;RAR----9-allcis-retinoicacid,RXR---9-alltrans(orallcis)-retinoicacidgeneexpression.(3)Influencingthesynthesisofboneandbothserumandmuscleproteins.itinfluencethegrowth,developmentandreproduction.(4)Againstcancer(β-caroteneismoreimportant)andregulatingimmunity4.Deficiency

(1)nightblindnessandxerosis(干燥癥)xerosisofcornea(角膜)cornealdistortion(變形)blindness(2)xerosisoccursthroughoutthebodyinfectionandpathologiccalcification（鈣化作用）

lesions;epitheliacellhorng(角化)；nervelesion;deformities(畸形)inthefetus.

influencingthegrowthanddevelopment(especiallybone,teeth)

(4)others:HbandimmunitydecreaseEarlystageLatestageVitaminAdeficiencyisaworldwideproblemthatleadstoeyediseases,severeinfectionanddeathinmanypeople.Mostoftheaffectedliveinlow-incomecountries.Itisestimatedthatabout750millionpeopleareaffectedbyvitaminAdeficiencyglobally.Vulnerablegroupsare:

Childrenfromsixmonthstosixyears.Pregnantwomen.Lactatingwomen.5.Toxicity

(1)Infants:transienthydrocephalus(暫時腦積水)andvomiting.(2)Adult(chromic):20-30timesofRDA.Fatigue(疲勞),malaise(不適),lethargy(嗜睡癥),abdominaldiscomfort,boneorjointpainorboth,headache,insomnia(失眠),nightsweats,lossofbodyhairorbrittlenailsorboth,指甲脆性，dry,scaly(鱗狀),roughskin.(3)Osteoclasts(破骨細胞)activitiesincreasing.(4)Others:fetusdeformities,yellowskin,……6.EstimationofnutritionallevelofVitA

(1)VitAlevelinplasma:

0.35~0.70umol/L(10~20ug/dL)–deficiency.

Butnormallevel(>30ug/dL)doesnotmeanthatVitAisenough.

(2)改進的相對計量反應(yīng)試驗，MRDR脫氫視黃醇/視黃醇,<0.03充足，>0.06缺乏(3)RBPinplasma.(4)Darkadaptation(5)眼結(jié)膜印跡細胞學(xué)法，CICconjunctiveimpressioncytology.(6)Symptomsofeye7.DRIsandfoodsource

1IUVitA=0.3μgRE1μgRetinol=1.0μgRE1μgβ-carotene=0.167μgRE1μgothercarotene=0.084μgRE(2)DRIs:

Adults:800μgRE/dPregnancy:1000μgRE/dWetnurse:1200μgRE/d

(1)Unitsβ-carotene:inplantVit.A:animalfood二、VitD(shortened)

1.StructureUltravioletlightUltravioletlight(1)RegulatingplasmaCaandPwiththeparathyroidhormoneplasmaCa

Ca,Pabsorption

renalreabsorptionCafromboneplasmaCa,P(2)Facilitating(促進)mineralizationofthebone

Preventingricket,osteomalacia(軟骨病)andosteoporosis(骨質(zhì)疏松癥).

2.Function佝僂?。篛形畸形3.DRIsanddietarysource

(1)DRIsAdult:5μg/d(200IU/d)Others:10μg/d(400IU/d)(2)Foodsource:SameasVitAandsunlight.三、Vit.E(tocopherol,生育酚)

1.Functionanddeficiency(1)reproductivesystem:

male:degenerationofseminiferous(生精)epitheliumfemale:impairingvascularoffetalandplacentaasphyxia(窒息)anddeathoffetus.man:Noevidencetorelatemalfunctionofthereproductionprocessinman.(2)muscularsystem:

musculardystrophy(肌肉營養(yǎng)不良):muscule

paralysisedema,leukocyteinfiltration(浸潤)and

segmentalfragmentationofthemusclefibers.(3)nervoussystem:

cerebellarencephalomalacia(小腦軟化癥)(4)vascularsystem:

hemorrhages,peroxidehemolysis(過氧化溶血)(5)biolodicantioxidant:keepthemembranestable.

others:DNAandcoenzymeQsynthesis,preventsynthesisofN-nitrosamininstomach.2.DRIsandfoodsources

(1)DRIs:(mgα-TE/d)

y:0~0.5~1~4~7~11~14~AI:334571014

Foodsource:

vegetableoil

四、VitB1(Thiamine)

1.Structureandproperties

Solubility:Watersoluble(1g/1mlH2O)；Meltingpoint:248oC~250

℃(atpH7)Maximumabsorption:235and267nm;Stability:atpH<5,stable;butpH>7,easyoxidized.

（硫色素）紫外光下呈蘭色熒光pyrimidine(嘧啶)Thiszole(噻唑)氧化2.Functionanddeficiency,toxicity

function

Thiaminintheformofpyrophosphate(焦磷酸)participatesasacoenzymeintheoxidativedecorboxylationofalphaketoacidto

ldehydes(醛)pyruvate(丙酮酸)acetylcoenzymeAα-ketoglutarate(α-酮戊二酸)succinyl(琥珀酰)Co-Alipoicacid(硫辛酸),NAD,Co-A(2)Thiaminpyrophosphate（焦磷酸硫胺素）asaenzymeinplantsandanimalsistransketolase（轉(zhuǎn)酮酶）,whichisimportantinthereactionof

phosphogluconatepathway（磷酸戊糖途徑）inwhichinterconversionsof3-,4-,5-,6-,and7-carbonsugararecarried.(3)Others:influencingthefunctionsofnerve,heart,

gastrointestineandmaintainingappetite.Deficiencyberiberi

飲酒可加速缺乏(1)Dry(atrophic)beriberi:

0.2~0.3mgB1/1kcal

peripheralneuropathy:anesthesia(麻木),tendonreflexesareincreasedandabsentfinally,musclesatrophy(萎縮).

(2)

Wetberiberi(subacute):<0.2mgB1/1kcal.

Neurologic,cardiovascularsymptomsaremoreapparent:

edema,heartenlarged,tachycardia(心動過速),venouspressureincreased,digestivedisturbanceswithanorexia(厭食)andconstipation.cardiacfailuremaybeprecipitated(突然發(fā)生).Wernicke-Korsakoffsyndrom:腦性腳氣病Toxicity

VitB1producesavarietyofpharmocologiceffectswhenadministeredindosesthousandsoftimeslargethanthoserequiredforoptimumnutrition.3.Metabolism

(1)absorption:

jejunum空腸(Na+,ATPandfolicacid葉酸)

(2)metabolismanddistribution

:combinedwithphosphateinmucosalcellandliver

20-30mginthebodyTPP80%TTP10%TMPVitB1inheart,liver,kidney,brainandmuscle(50%).10%(3)excretion:

urine:Vit.B1mainlysweat:90~150μg/L(inhightemperature)4.Nutritionalestimation

(1)transketolaseactivity

transketolaseactivitytransketolaseactivitywithorwithoutTPPTPP>25%,absent;TPP>16%,deficiency;TPP<15%,normaltransketolase(2)ConcentrationofVitB1inurine

loadtest:5mgbymouthor1mgsubcutaneousinjection,determineurinein4hours

<100μg,absent100~200μg,deficient>200μg,normal

Excritionin24hoururine:difficultVitB1μg/ginosine(HxR次黃嘌呤核苷，肌酐)

<27absent27~65 deficient66~129 optimum>130 high

5.DRIsandfoodsource

(1)DRIs(mg/d)

Y:0~0.5~1~4~7~11~AI:

Y:14~18~PregnancywetnurseAI:1.5(m)1.2(f)1.4(m)1.3(f)1.51.8

(2)Foodsource

InChina:plantfoodisimportantsourcelegumes(豆),peanut,cereals,yeast.

五、VitB2(riboflavin)

1.Structureandproperties

structure+2H-2HWatersoluble(slight):12mg/100mlH2Oat27.5oCStabletoacidUnstabletobase,lightVit.B1-proteinorphosphateinfoodsarestableProperties2.function,deficiencyandtoxicity

(1)function:

Essentialforoxidativeenzymesystemsinvolvedinelectrontransport,includingtheAAoxidases,Xanthine(黃嘌呤)Oxidase,succinic(琥珀酸)dehydrogenase,glutathionereductaseand2conenzymes:flavinmononucleotide(FMN),flavinadeninedinucleotide(FAD).(2)Deficiency:

Eye:

vascularizationofcornea(角膜血管增生),darkadaption,cataract(白內(nèi)障).Mouth:stomatitis(口角炎),glossitis(舌炎)(maptongue).Skin:

seborrheicdermatitis(脂溢性皮炎)aboutnoseandscrotum(陰囊)inmenandorogenitalsyndrome(口腔－生殖綜合征)inwomen.Animea:influencingtheabsorption,transportandstorageofiron.Others:influencingthegrowth,developmentandreproduction.(3)Toxicity:rat，10g/kg.bwnotoxicity.

3.Metabolism

VitB2proteinVitB2

Absorptioninsmallandlargeintestine

(HClingasticacidisimportant)

kidneyliver80%

urine10%fecal3%milk

sweatAbsorption

Distributionandexcretion:

AC>1.2deficient4.Estimation

(1)EGRAC(紅細胞谷胱甘肽還原酶活力系數(shù)):FADGSH-Px24hours:147.5~186.1ug(normalinChinese)loadtest:4hours(2)VitB2inurine

<400ug absent400~799ug deficient800~1300ug normal>1300ug sufficient

VitB2ug/ginosine(HxR)

<27absent27~79 deficient80~269 normal>270 sufficient

ConcentrationinRBC:>=15ug/100mlnormal5.DRIsandfoodsources

y:0~0.5~1~4~7~11~AI:0.71.01.2

Y:14~18~PregnancywetnurseAI:1.5(m)1.2(f)1.4(m)1.2(f)1.71.7(2)Foodsource:

animalinternalorgans:heart,liver,kidneyandlegumes,yeast(1)DRIs六、Niacin(nicotinicacid)Vit.pp

1.Structure

niacinniacinamideBeimportantpartofcoenzymeⅠ(NAD

nicotinamidadeninedinecleotide)andⅡ(NADPNAD-phosphate)whichserveaspartsofintracellularrespiratorymechanismofallcellsforenergyreleaseandessentialorcellularbiosynthesisoffattyacids,steroids,proteinandDNA.NAD(P)++2HNAD(P)H+H+

2.Function3.Deficiency

(1)dermatitis(皮炎):appearanceonpartsofbodyexposedtosunlight,heatofmildtrauma(輕度創(chuàng)傷)-face,neck,surfacesofhands,feet,elbow,etal.thelesionsarebilaterallysymmetrical.(2)Diarrhea:itmaynotdevelopinallcases.diarrheaisaccompaniedbyvomiting,dysphagia(吞咽困難),mouthinflammationwhichmaybesopainfulthatthepatientrefusesfoodandbecome