PB-226 018

INTERRELATIONSHIPS OF LEUCINE WITH LYSINE, TRYPTOPHAN, AND AS THEY INFLUENCE VALUE OF CEREAL GRAINS FOR HUMANS

Constance Kies, et al

Nebraska University

Prepared for:

Agency for International Development

1972

DISTRIBUTED BY:

National Technical Information Service U.S.DEPARTMENT OF COMMERCE 5285 Port Royal Road, Springfield Va. 22151 -,7

SHT PB 226 018 ter'e0a ti.un ip. of' Leuci.ri2 wi.th I.ysl ne, T'Pyptopha, arl 1JiUbin A- '.'hiey ]n[l'i.u-:incc rotelin Va].ue of Cerealle "1'... o 6.

7-\, oII(s . 8 erforming oaaizti.til,n Reipt.

I'. t''zi,, . icivao N.ame a.inAddrt. s 10. Project/Tatik/Wnrk Unit No.

-"* ". ", " iAID/osd-].2

12.p,.u,:,r;:i< Oraniz:ittion N.inm iind Addrvss 13. Type of lRoport & Period . .nt ..of' ,tat Covvred ' or rnter nal leveloprrent 40114tl :,-,. n., D.C. 20523 14.

15.. t y Notus

M6 A. :, , o._:..i.:E~rn. betw.:en the typi ca] aixLmro acid proortionality pattern

...... - :. corn :, .,2.3:13 the 1l. h l.eucina cont;ent of corn. A series of three ." in l.....1o'w in pot1on to hurtvi rec'.s or for which availability is .....I all± ... , a,-,,lt h n..:,rsubjects ,;er fed diets containing ).0 g. . r (day 'L. .hoie_ vou.i whe't ,.i.rI or' wle-,'oux'd grains plus t4. _ tot.! - evl com~onLy f',Pc.ubd : n corn fgailn. The re'sults sugest that ...... cn m ort . ctor in the relatively poorer

fc-. - ' ci' corn faIn, .1ncoripar..-,or to wheat grain in huan feeding 7: >io of hc i;'i;- ,i effect-1ve rogardless of. " .T "" " .oflysine d was not comple'Ly able to -..:...:-.,...L. : of the .,, e, -o .'u of leuc'Lne. -1i.acin supplement­ ..... •,.e> "-' at hi- P.chie-intake lovels. Trytophn supplementation ... -.?.r hr4 _:vl:,we;/nive of'.rwt; a both levels of leucine ...... '.+.%... '...... +...... +

by 176. 1 , , O'-ri-End.d Tv.w., Reproduced NATIONAL TECHNICAL INFORMATION SERVICE U S Deportment of Commerce Springf,'IrI VA 2?1M 1

17c. (.O.TI FuIh/Grlu, 18. Avail ahbiliy StnummrneL 19. Sccurity Claiss (1 riS; 21. No. of I'age.s

I •20.Security (:iss (This Price INCI.ASSIFVIEID t ONq: t: rV1,.-, LL v. 3-7;.) USCOMM.t-C 1495P-P72 Interrelationships of Leucine with Lysine, Tryptophan, and Niacin As They Influence Protein Value of Cereal Grains for Humans'

CONSTANCE KIES and HAZEL M. FOY, Department of Food and Nutritin, Agricultural Research Station and Collge of Home Economics. University of Nebraska, Lincoln 68503

ABSTRACT [lhe nItost strikilg diffe'nce letss c' the tyl'dcal prolprtionialhy patteri. i' wheat and corn grains is the high letuciic coittot itcorn. A series tit three sludies Iias bee.n co iplelcd oni possible leiille interactions %vithntlitrjents sutpplied by these cereals in low an ount in proporlion to hlnitan needs or Ior which availability is questioned. li all three studje., adult hinnila lshiects wvere fed diets containilg 4.) g. nitrogent iN) per day froin %w-hole-grouid%%heat graijn or whole-ground wheat grain pius I.-leijice to total tlhe level contitonlll found in coro grain. The spcile"ic oblectives were to comtpare tile elfectiveness oil protein iutiltire of' supiileentation (with' I sine, try tophian. and nliacill of wheat die.%conlaininlg hil. and normal a iounts of' len .ie. Mean N balances (grains per da%. respec ii"'ly %,were: i lIle eight sUbjetS ted Whit aione'.%he'at piluIS lysine. %%heat plu licine, ir witat itlS leticite aInd lysilne. 0.66, 0.12, 1.018, and -0l.0; +of'(lh nine subjects led whecat atone. vh%eat pit1s trYlptolitan. wheat p1lus lenicitle, or wh;eat plus luecine aind trYlltiophan, 11.90, I.(I, 1.19, and -1.39; of'lie ten sllcs le'd wireat alone, %htat [luIs iin. wlh+:l tll.1licine, or wheaIt piis lCucile and niacin, -0(.95, 0.87, 121(. and 0.92. I'iese reNults suggest Iliat iigh-leel LicL' content (if corn is an imtiportant factor in tlie relatively Ix[orer nutritiontal performair ce tf' corn ralin, in colmparisont to wheat grltn in hunian I'ceding trials. Lysine sippleienltatintlof wheat wa-s ,hoiwn to lie eff'ectiv. regardless of' le"ttic conten , alihouth leItll lit(Itof Ilsiite added wa not comtpletely ahle to iovercotltln- the adverse effectl'of the increased anount of" leucine. Niacin stitpplcnilation was effective only al iig h .,ucite-intake lecvels. Trypliophan ,Upple mentatin vas ineffective or had t slight neative effct0 at bolh evis (ifi'lucihin e intake.

The tiaci tn-lrvihOl l:n-dclhtet disease pelilagra is C.tnil yiasstciated with corll- a.ti ,peoples tf" tIhe wt-rid. Although cort cotllalils appreciable allnolltits of Iiiaciti. it is seini!l1 utvtilable it) tlte litilaiu becatusc l its bound form 0]). E-vidence suggesis that this Is list) Irue ohtihetheiii coainltld il wheat gralil (2,3). Lysiie alid tr itopiani lave been I'otind to be Ilite irst and second linlititig aminio acids ill tuost lines ill" both corl and wheat graisl under ts.Uai conditions for mualilce o1 adeateLl protiltl trilUtreu tilelit t;til idtall (4,.). Hlowever. wheat grain ilas bec t fountd iti have a ligither proltein valhiu for theithunian adult tian ctrn ,!rain (0). A c)mnparisotl if alllilt acid proportiotalilty patlerls off tlpical lines of w eial aid corn grains (7) with enhliotilier alld wih theIniin ainnilo acid requirement pattern for Votilg men (8) iidicates tla theitiosi striking difference alllol tiese pltteris is the iigh elicit col ltetll aid lower lysine and lrypioplian conitetS o cori graii incotparison to Itwhea t 'ie principal tlijecive of t]i current project was it study (lie effect on protcin nutriture if" ltinian adultS of itieraciotis hetween hhih aid nioderate levels of"

]Pu ,blisht with t e aplrval (if thle )irector ts Palpeir No. 3067, ,Journal Series, Nebrrska Agrfotr.'itural tesearlh Station. Supported in patit by USPIIS (rant A-10-69; also, ilt part, a c'-,ntrlbuton to thie US)A C.S.t.S. I eglonail Project W-57. Researn reportet Was conducted under 'rojeLt No. 91-(07.

Copyright ( 1972 American Association of Cereal Chemists, Inc., 3340 Pilot Knob Road, St.

Paul, Minnesota 55121. All rights reserved. 223 224 II L'INI ANV ( RIAI. I'RIIIN V'AI.LII' Vii. 49

,.].tr\. IcIciic aInd mlacli. lrv'plop l lan. llId IvSllC Illlit;lltoll. This tIia Itr ohjectiv'e Wis sulhdividCd 11llh0 Ih l'ollowili- workmit objectives: I ) To cnllp;l'cmtplrellltlLltl'tllvi.'IjCo ;Ihl t' fIlo Ilulan adult of whelat rain I ll ic;.t 1";1111\I b letlcii'l]ui added io silttul;lu . tlh;at level of lellcteiCc ulnlotliy I'iluiid i11 'Ol'l) tl'lll|. .2 i" colIlai]1C ilhc prol ill IlullrlllVc t;lue 1"Iysll -.tll)ltc.lllll cd Wheat l;IlIl Io StlW lluiltlJo Wlllc-\V.i.lt .1111\VIllII(til adii'd icticu lt(sllli( li.11 tlfl. STo C'*ollillare thec proleill ll oweltl 1 thac-Slpplente;ited lei it)

Io l:L'l|S~tllu'll'n W'u he'd l v, Wr'11nh lh ed lu.'e (Scilll ln C on).

EXPERIMENTAL Design "l,,.. ' . cIIl ICtel' II1hree tiide.etidi utL ,,ludtS. r1n Sllnl II tiSeouslv I)11t with diflerent experimental siuihje,.'s. Ladi 33-da\ study was composed of a 2-day Ill.ll' 'el (N)-dplelitsu! Iperiod. I ,3-dav N-adjustmlut period. anid I'or experilental peritds tif' 7 days each. 'Ilie exCeaCIrIIIClIll tk.sl2ls arC gJ\'In Ill "lahleI.

TABLE I. DIE"PLANS

No. of N Intake DietSlerentb a Period Days wheat Kind Amount ...... g./day

Study A Depletion 2 0 None ... Adjustment 3 4 None ., Expt. 1 7 4 Nooe. Expt. 2 7 4 Lysine 960 Expt. 3 7 4 Leucinu 1,676 Expt. 4 7 4 Leucine 4 lysine 960 4 1,676

Stu..y B Depletion 2 0 None ... Adjustment 3 4 None ... Expt. 1 7 4 None Expt. 2 7 4 Tryptophan 212 E xpt. 3 7 4 Leucine 1,676 Expt. 4 7 4 Tryptophan 4 leucine 212 + 1,676

Study C Depletion 2 0 None ... Adjustment 3 4 Nonr ... Expt. 1 7 4 None Expt. 2 7 4 Niacin 25 Expt. 3 7 4 Leucine 1,676 Expt. 4 7 4 Niacin Ileucine 25 1 1,676

"The following number of subjects were used in each study: eight, study A; nine, study B; ten, study C. Order of experimental periods was randomized for each subject in each study. tDuring the adjustment and experimental periods the diet consisted of wheat yeast-rotls; apple­ sauce, 100 g.; grern beans, 100 g.; peaches, 100 g.; pears, 100 g.; tomatoes, 100 g.; dry bouillon, 3.5 n.; and variable (dependent on caloric need) amounts of sucrose, buiteroil, jelly, hard candy, aid soft drinks. Purified, crystalline L.form of Leucine, lysine, and tryptophan were used as supplements. March-April C'.KIES and II.M. IX 225 )urtltig (lie tn'troductorv N-depletion period of aill three studies. to(tal N intake per subject per day was f0. g.. as provided by IlII, bisal diet • (lab.le I). liis procedure ol'prelinilarI f'eed Itieof' a velr low proteill diet has beell found in tIhn laborato r to hasten the attainmitent ol N equilibrJUi 1)yvsubjects to l:iter. nttrderitely-hos-lproteni experimental dielts. Total N intake duriii file3-day N-adjustinent period of' each study was 4.,S g.pet sibhecl pe r day 4.0-. N froit grotind 2 wheal raII and 0.8 g. N f'romthe hasal diet. Objectives of' this period Included iad jusitienllof' subjects to tilelevel of total N intake to he used durinttg the experitenital periods. estina loll of indivt]dual caloric requir,-lt,,s for approxmiiate weltht andnattteiiaice.tiltrodUctioi of'"subjects iotheir duthies and tesptisibilities. Total N iiltake during the four experiiieitil ixritods comprising, each of tlhe three st idies was 4.,. per sulject per dav 4.0 ,. N 'ronli wheal and suIpnnieitted wheat, atnd 0.8 p. N front the basal diet. lhe four experimental periods of each study were raiidoiltl arratiged for each suhject. IllstudV A. tile experi intital-diel variables conisisted of' the iitisiippletented wheat diet. wheat diet plus leuiciie. wheal diet plus lysine. atnd wiea diet plus leucInI and lk ste. II stndy B. tlie experimentaldiel variables were the tilstppleiienited heat diet alone. the wheat diet plus tryptophaln. the wheat diet l~huis leutinte. atnd the wheat diet plus leuciue and tr.t%ptolian. l:or slud ('. tile experiiential-diet variable, were tilettisuIppIleiientlted wheat diet. the wheat diet plus leucitie. the wheat diet plus itiacin. and tilewheal diet pIntS lecihe aid nia.in. Levels of' supplmenieitajoti per subject per day were as IOllows: leticine. I .67o g.: (r)ptoplan.0.212 g.: l\'sine, .0(f g.: anid niaci (as liotiaiiide). 25 lng. The levc! ol leticite was selected to ralise the ujotal leucine Contellf oi'the hrlealto that ctitiitly 'oulld illco.'l'l The levels oft' 1n1.lrirplphat sipplementation were deterntuned b\ corllaisol of the levels oIfthese two essential amtuito acids ilt 4.0 g. wheat-proteini N to the RCcoluttteruded lss.+.erutiil Anitno Acid Proportionality Pattern for Young Men I,').The ni;iu -supplellietliltatioll level was slected to "ive sliulitly more than tile recotitelluded niiCacin iit:ike for hunlan adults as set I' the National Research ('ouncil )1. Diets ('aloric intake hr eacuh suhject was kept relatively constant ;t the anioutit required for weight taiitetance by adjusting [ie intake of starch, fat. sucrose. hard call(]. aid soft drinks. IlIIorder to better sinulate field-study conditions, tit) v'dded vitamnin and mineral preparatitris were used. The ground vheal grain was prepared for consumptipt in the form ol' a yeast-risen roll. The f'ollowng iiig'edients were mixed. ba.ically in the manner suggest.d by Steele et al. (10) or pr'parattol of' this product: 18 g.ground wheat. 132 g. ',v atstarch. 24 g. sucrose. 40 ,.il)].2 ,. ,!vcerul inoh'lste.aratc. 8 drops glycerie. salt. mucilose flakes. anid water. Ingredient's 'vere weigh.t 4ndividuall for the Jaily allotlment. '[his allotnientt. after mixing, was divded into three equal portions for conusitpti l ill teie three daily iteals. atnd baked. )aily allotmuenlts of' vitaini anid purifled essential ajiltlo acid supplemlenuts determitied b' tlie experiniental design- were given to tIle subjects ill water

\Wh'vt grain (Co .i.t, Of highrIi ritn A tlis 66 and c'a nli'tl'tines) was grown anid 5upplited gratis b.' the I) ipartnlment of AgroionN.. U'niv'ersitv -f Nehraska. It was )rep.red as a wholt-ground flour. 226 1.L' ('INE AND ('I.RIAI. PITiFIN VAI.UI- Vol. 49

solutionts. 'Tihese were ee liall di,'idCd atiloji the three daily meals. Other items comiiposing thle dielt ere as sited if)lTable I. Subjects A totaj of" 27 iot1 aditult111meII and womtte; weiteSubjects for the three Studies: Ceeh, 1t0or,,il,, A. lltlie for stnd\ 1. aid ili flor situidy' C. A!l these volunteers were studetlls of tlie I 'niversi iv of Ne'braska or Nebraska \\Vesle'a, Un'ijversity. All were 1i1 uiod licalth :is determilied b physi:ajl exalltmaijoihs and health records evaluated by medical l)lisicNiis ofI tile Stldent Ilcatih Service oi the Utiiversitv of Nebraska. During the stuidy . Subjects contisied itieals ill the itietabolism laboratory of the I)eparliileit of lood aud . itniverslv of Nebraska. lowever, they tiiaii;uiiied their usual study, work. aid oilier II\'it(, roulines. l)escriplive data are niven Ill Table II.

Analyses The N-balance tecliititie W.S usled aS tle Imin criti iou of' evaluation of' level of protetin uiritiire. Nillocn lCteritiiiatoiis bv the boric acid modification of the

TAHLE I. VITAL STATISTICS OF SUBJECTS

Subject No.a Age Sex Height Weight cm. ko . Study A 350 19 M 184 88 351 21 M 176 89 352 21 M 170 69 353 19 M 178 86 354 21 M 185 77 356 19 F 159 50 358 1 F 173 74 359 20 M 185 84 Study E; 361, 19 M 170 95 362 19 M 183 85 363 20 M 187 78 364 21 M 178 66 36b 20 M 180 76 366 34 M 168 68 367 21 M 176 76 368 20 M 170 75 369 25 M 179 76

Study C 370 22 F 170 54 371 19 F 155 52 372 18 F 168 66 373 18 F 164 61 374 19 F 173 61 375 21 F 163 57 376 19 F 169 66 377 20 F 168 66 378 18 F 173 65 379 25 M 185 93 aThe ethnic group for all subjects was white/American. N~Irch-:\piil C.KII S aid II. M. I(.).X 227 IKikld;ill nt'tltd (II ) w'rt' Ilt~dt' oil slpics o11''ood,;llliiltlo acids, iIlite, ald Ieces. i'sc lidilelial. %%ere collecled aiiu prepreil or alla\'sI ;iccll'dill', IilliIlluillods lrekiitisl tii dcsciib'd (112). I)a\ N ex.'ci IJ"Iiii tiritc \V I h;IsCd u cI111'.l-lql' . daill 24-hr. aid N C\CIClilli iII tic ccs %%;i isd M iLIlteav'ere v.alues of 7-ali\ llilopiolcs. )ail\ iirriie creaiiliIl C\rC.lJoiI. iIsed .is;11itled \ 0' I,:Liiratc\ ill" 24-hr. iine co'o]ltillks. \%rcCTt]rCI Miled h\ ;I n1od1ificaltjill Of I IIC prcedtire describCd )'.Iuhu (13). k' N11:,i \ V1101',1J001 d !lIllipll] .' ,'co\ll, icd li l I',ll lXi .fl l Ie ' \ l 1a lillgof e i'ch."ltd;\ ,lildl lilt.''lid III Ul"'h l ]Cfll J)CiIkield ;\W.er Mil \let]d1). 1l 0N]UIll I l l.01,1li; \i I t .'.tillll.flli LAu. . 1dc,,.rbl 111dill . ,i;i'111 l er (14 1,fl. pol~ssililI. l1.'112. ill IllillllolJllL I gtiih'iai 311\sIcail silahlis. SIdiitsiih. 11.\ilsst',. IlII Illt' M IA.\ W,'soIf ,ari;lllc's alnd )illicall's MuliJple Rain.e ICS. \%0er disc 1\ lle t'llice III A'liilnltil-c Stall1ical I ahoraor\. Unle'rslt\ i)l' Nebraska.

RESULTS AND DISCUSSION Nllit'ei-i'Jha iihn., ;it. 0 .'1;.llil I 11 [li Iethree .stidies a.liv'i2 eell iIII s. I. 2. aid .". Me.ill N 1%laii 'esti1' sii jccis ill sl.ti A ille r'c'elV llli e whe'.ll; diet 'dile. filte WilCal die[ pi Islsine. tile"ieat diet pils IIt'tic. and [lie wheal dletl pls leiucite

* ,S 1.0.

S 0 it 365 *362 6•,3o . * ,, °6 ~p,61 °°3 -1.0. ,*369 X +u 3 A 3653 .367 ~

z - + S. '. - 2.0 . 36 6O i ? 366 36 6 3*36

30. z -30.

NONI LIlJI LIUCINI LYV1.041 L UCINI NONE TRY LEU TRY. SuPIIMINTp tO Wi AT C(lr Stilplement LEU to wheat diet

-30. * .. z

NOr NIACIN ILJCINIl NIACINA LI UCINI

'uPPLIMINT TO WI4AT OUT1 Fig. 1 (top left). Effect of leucine and lysine additions to wheat diets on the N balances of human adults. Fig. 2 (top right) shows the effect of additions of leucine and tryptophan; and Fig. 3 (bottom), of additions of leucine and niacin. For each figure, the dots represent the average N balances of each individual for the 7 days composing each experimental period, and crosses represent the mean balances of all subjects while receiving each diet. 22X 11U('NI. ANI (1RI A. IT)'11 IN VAI.I.F Vol. 49 alid I'slle, were A..2. I .(JI.. and (.b) g. of variance N jxr La. respecI ively. A ilIyses indica ed dillfeelices Ii valles It '.e lall. lile5;, ,!Icllafcalice. level o " Applicalion of tw D clincari, value for ultpl,., Range Test inldicated that tle leicirie sipplellieit alh1e Was dilereit value 'rotli all othler %,allies. 1h1 file (Ior h sol s ipJIleii¢litatj ia w se tfrentffes from all Lt her values: where,s tire \'alticsor l btl Sll deiiiupplellielitaltiallrid I'or IlciiicJ %,er, di .-phIIs-.x,,j ie Stihn)IIIeil s f'll l'rm i the l\,lsie- or the le.,ne-vil pplellelts. line,,were ll sgnilicai tlI dif III sludN 're-It fronl'ach otther. 13.mean N balances of subjects ted lrypt,,phal. wheat diet aluo.n, wheat diet plus hlfieAt i12 plus leuCILJe. and Wheat s\ere 0(90 ditI plus leucile ,rid r'ptop)hiarI. j (). .1 ), and 1. ). N pe,.r resal+'ctivek .ly ksesla. of, Val llCe Illthc led diflferen~es. of the l)tnea'\ MlItiple s nlljicallll;Itgreater than the '' level. Applicaiiin l-Rge Test indicated that restuls SuihtllleliieritariLlr oblained \%ith eleciie anid \ith leillcie ald li'Vlt)I0Ih;aII dilfeiel trtom SiippiiiCiII were significantly ihere ulls obtained lr,.mt.l Ia Ol SIlIl.,h.,llle nrpl0phal d l1i011hll)IIih .' rite 1.lled dhets(grealrthan 5',level). ll sIly,d . ie i N halaices of subhjects fed wl;eal ale. w\heat plu, letlcille. whtiat plus Illlill. anld \Iilt p.l leit.cle II niacin were O.Q.5, (J.7. 1.20, alid 0.0)2 :,.iensN pe..r (ho.. ..r .. r clies of variancle ildicaled differenices .llllu, Irealllellis lo be prI..'ll (greater I)uncani's hlliple Raupie "est indicaled "tllan 5',; lvel). Applicalioill f tlha results wilhiletinile supplenliellaIl]oithe w\'ere '-lli'icat different (5'; level) trom resulls obtained with "5upl~l) lle ltentil.oiiI iieplse- t- u'l niacin Stilpl.eli lat ll.o)r110 ,lIppilc lIlatpujoll. Mean N balatices of subjects paricipating i Oh three stdie. ilsUppletmented wheal while receivill. the control diet varied: however. results were ilo I'uind 11u104 tie three sudies to be siInlficamItl, different. These necessity differences emphasize fle t)I' pieselfllrig all experimlienital variables to each subject ill laboraortu -ctolrolled N-balance among diflerent studies. rather lhani alleiiplimi to ise comlparisons . snall grutips hutlilmans. While spread greal allong tf'tie N-balance data was subjecls ollally one diet. the pat tern responses oL individuals illmost cases duplicated [ie direLiiowial change ofIImean valies for AllioIih 1ot Sp)eci'ically each study as a whole. examined ill lits stUdy, earlier work shows only pu c;irreialiL from Ihis labo;alor' of'proleini requirement wilh N-halaiice body weight. Spreads of data frum huln',s are typically large. Results of ollier chinical Iieasureilents signtificant are zuiven in Table i11.There 'ere changes ii t liese data owing toexperimental no treatment. and all values for all subjects were within "nornal' hrie results range. of tins study demonstrate thal inchlsion eSSenltial :nlltlO ohf excessive amouniItis of the aLid lencine has a negalive effect hluiiiaris. This oilprotennutritilre of adult then stgeests thai evalalion of cereal as products (anid other products well) fir prolei value shuid cionsiuer ami no acid balance ii ternis of acids. such as leticine, supplied in anidl1 sutper-uoinilaamountls Iswel as those at less than ideal levels. The supplied objective of the current project was ntit protein valies of to compare tire curn arid wheal grains, billrather It) ni.y he interacting define some factors which to a ffect proteii vallie ur to account for possible differellces ill predicted arid demonstrated values. Leichit interaction with itiacinii seemed in this study tobe aniimportant ,larLh-,,\pril C. KI'S : II. I. (OX 229

TABLE III. EFFECT OF EXPERIMENTAL VARIABLES ON SEVERAL HUMAN BLOOD CONSTITUENTS

Mean Fasting Blood Value for Group While Rceu,vingl) Plus Plus Leu and Lys (A) Lys (A) Normal No Plus Try (B) Try (B) Determinationa diet surppl. Leu Nia (C) N~i. (C)

Blood irea N, rg. i100 ml. Study A 15 5 5 5 5 Study B 15 6 6 6 6 Study C 14 B B 8 8 Glucose, g.'100 ml. Studv A 104 89 90 90 89 Study B 94 90 90 88 89 Study C 96 BC 86 78 86 Total plasmna p3rotuinl, g./100 nil, Study A 7.3 7.0 7.0 7.0 6.9 Study B 7.4 7.2 7.1 7.1 7.2 Study C 7.3 7.1 7.2 7.1 7.1 PlasnTa albunin, q./100 nil. Study A 4.7 4.6 .1.5 ".6 4.5 Study B 4.7 4.6 4.5 4.5 4.5 Study C 4.5 4.5 4.5 4.4 4.5 Plasma globulin, g./100 ml. Study A 2.6 2.4 2.6 2.4 2.4 Study B 2.7 2.6 2.6 2.6 2.7 Study C 2.8 2.6 2.7 2.6 2.7 Plasma A/G ratio Study A 1.8 1.9 1.7 1.9 1.9 Study B 1.7 1.8 1.8 1.8 1.7 Study C 1.C 1.7 1.7 1.7 1.7 Hemoglobin, g./100 nil. Study A 15.9 15.0 15.0 14.9 15.0 Study 8 16.2 15.7 15.7 15.4 15.7 Study C 13.9 13.4 13.2 13.2 13.4 Hematocri. ml./100 -nl. Study A 46 44 44 44 44 Study B 46 45 44 44 45 Study C 42 39 39 39 40 Cholesterol Study A 182 179 176 172 167 Study B 190 172 173 184 174 Study C 190 172 171 174 181 Serum glutamic pyruvate transamnase, Babson units Study A 30 35 35 34 35 Study B 31 40 51 55 42 Study C 26 29 26 31 26 Potassium Study A 4.4 4.4 4.2 4.2 4.3 Study B 4.2 4.3 4.2 4.4 4.3 Study C 4.4 4.1 4.2 4.2 4.3

aDeterminations were by standard laboratory procedures of the St. Elizabeth's Hospital Laboratory, Lincoln, Nebr., as described in an earlier paper (14). Additional informa­ tion regarding methodology and quality control (within 1% for method used) isavail­ able from thislaboratory. bValuos obtained while subjects were maintained on their ordinary pro experimental diets (Normal diet);on the unsupplernented wheat diet (No suppl.); on the wheat diet plus L­ leucine (Leu); on the wheat diet plus L-lysine (Lys), L-tryptophan (Try),or niacin (Nia); or the leucine-supplemented wheat diet plus lysine, tryptophan, or niacin. 230 I.;L!U('INI AND (' \t. IROTEINPR, VALUIF Vol. 49

posstbilit y. Nacin lsupplementaItion evideitv had ito demonstrated effect at "1Iotrinal ilttakes of letLcine; however, when leicdiie was added to thIe diet. niacin supplentilttatio iresuilledin restoration of N retenltion to ifte same level achieved when ito additional leucint was included. No inlteractions between tryptophan and leucine were demnonstrated, l.ysie was evidently tile first limiting atnino acid in both leucile-SUpplemented. and itonsuppletneitled wteat. which suggests that lysinue aid leticine were ,opieratinig as itdependent variables. Niacin StlppletiteitItaIcn has been detmonstrated to restilI in ittlprovement in protein t uriture of Itdlt Ittumtan subjects maitained ott corn diets (15). Niacin-trypt opIan interrelatitinships, particularly pertaining iofactors influencing tryptoplhan.to.-macin conversiot. have received considerable research attention I6,17). Interrelalions antiong isoletucine. leucite. and val ine affectiig 'protein nutritture of Iitttis have also been investigated (I 8). Feeding excess leticine has been demonstrated to inflntitce excretion io aci n-trplthali metabolites in botIt Ilitt its aztd in adult rats (19.20-11 ). Ani adverse effect onf N retenttion of feeding Iigh levels of1letciite to adtill rats has aliso beci reported (21 ). ihe results of'the current project are in agreentett with these earlier reported restilts. Thait rpaqu'-2 lines of " corn ]have protein nutritionalI qualities superior to 1tistialI" corn liies Ithas beert deinonstt;aled (22). This ittmiproven lt has been tistial ly credited itole reltalively higher lysine content of opaqu.2 line corn grains: however. these lines also are characterized by a lower than ustial leticine content. l)ogs maiinltaiied oin Iton-ptaqie-2 corn rations, or oit opaqe-2 corn rations with leticine :ddit'ioits. developed the iiaciit-tryptolthait-dcficienve disease blacktongue. whereas dogs m:littained on tinstipplentented opaque-2 corn rations did not (23). These results stiggest that Ihe relative exc"os of leucine in ordinary corn diets itay be ilortallnt in development of the Ititan itiacii-trylto .a -deficieney disease pellagra. supportling but not explaitiing tle apparent effects of iniacini-leticiite-trvtollan interrelationships on htiutan protein nutrition demotstrated il'the present sttidy. Additional dala is needed to explain le biochemical ieclianisms involved in these demonstrated leticine-niacin initerrelationslhips. Ilowever, from a practical viewpoint. the current project stresses the need to define total fit ritional environnient Sn indicating quantitative needs for any single nutrient or in assessing ititritional valte of a Iod product.

Acknowledgments ric authors wish to acknowledge i11wcOoper:alion of the 27 young iien and women who were suhj.cts for this project. The authors would also liketo thanOk and acknowledge the following individuals Ior technical laboiatory and diet labor:atory assistance: Mary Rhodes. Elsie Ilsltiop, %large Kunzman. Jean Malzer. Frances mavfield. Dorothy Morris. Evelyn Coufal. and Deanna Sivers.

Literature Cited IFRAZIER. E. I.. and FRIFI)MANN. 1'. E. Pellagra. stuly in h,,an nttrition: Mnltiple factor principle it' deterina:tation t liinti iin vitaniti retlureltents. Quart. Bull. Northwest. Univ. Med. Sch. 20: 24 (1946). 2.KREIIL, W. A., and STR(ONG. F.NI. Studies on distribution, properties and isolation of naturally occurrng precursor of nicotinic acid. J Iiol. Chem. I56: I(1944). %larch-April C. KIIS and II. kI. [OX 231

3.3RISSANI. R., \VIILSON. I). L., ('IIL!N(;, M., BFI.AR, %I.,and SCRIIMSHAW. 1. S. Suppleecntation of tereals with aminto acids. IV. Lnie supplementation of whi'eatllot fed to young children at dif'¢rent levels of' proteini inlake ill piles.nce and absence ot" tlher aiiJno aids]. J. Nir. 79l: 333l. I1903). 4.KIS. CONSTAN(F. and FOX. IIAZI:L M. E'ect of level of total intake oil second limiting ainilno acid in corn f'or hmians. J. Nutr. 1I(0: !275 1I19701. SKIES. ('ONSIAN('I. and [OX. IIAZI1.MI. )ectrniiatli of tie lirst limiting amino acid of wheat and triticale girain t'or li1;aii. Cereal (Lm.ii 47: 615 0 97(0). 6.11iltRICKER.., MIT.,NIICIt:LL, If. I1.. and KINS.I..\N, G. M..The protein reqiirements fadult linian subject iteriis (it' the protein cointained in ihdividti:al l'o0 and I'ood combinations. J. Nnlr. 30): 269 (1945). 7.ORR. MI.L., and \VATT. It. K. Ailnio10 acid content of" foods. IHonmc Econonlics Research Report No. 4. LISI)A . Washington. I).(. I 1l957). 8.ROSE. W. C. The amino acid rcqliie ntits of adult man. Niitr. ..\hstr. Rev. 27: 631 (1957). 9.1:001) ANI) NUR IIION IOARI). Recimlmended dietary allowanices, 7th ed. National Research Counci Pub. No. 1694. Nal...\cad. Sci.. Washingtolln. I.('. 11908. 11.STI F I.. It. F.. IIJORII.ANI). MI.(C.. and II.OCK. W. I). A yeas lc,,ventd low irotein bread flbr researcih diets. J. .\ner. I)i... Ass. 47: 405 (1965 ). I I. SCAI.IS. IF.NI.. and II..\ RIISON. A. P. Ioric :cid iodification ol the Kjeitall iethod for crop and soil analysis. J1.Intl. 1.ig.(lin. 12: 35(0 1920). 12. LINKS\VI I.IR. I1.. GI.S0IIWENlI.IR. I).. IELIISON. .. anti FOX. IIAZE MI.N.A;vailabilit\ to Ilia of :;dlno acids °'oi t'ootls. I. (G;ncralmethods.J . Nuir. 65' 441 (1958). 13.1OLIN. 0. O the det!cililiatioi of creathnine and crealine in urine .1. I . (heni. 17: 469 11914). 14.KIFS. (ONSTANCE. FOX. IIAZ.L ... WILI.IAMS. F. R. Studies oil tinc. stress, quality and quianlit :c as fict its in tlie non-¢pecitic iitrogen supplementation of corn protein for adult nen. J. N.tr. 93:377 (1967). 15[.KIFS, CONSTAN'I: aid VON. .IAZIL NM.I f'tc of' niacin inlakt oi itlatquacy o corn plrotein to Incet lulian .uldldt need. Ablstr.i I ed. Proc.. IFed Anier. Soc. I-\p. Iliol. 28: 372 (1969). 16. VIVIAN, V. M%.Relatioship between tryptoptanliacin nctabllisi'. and chailies in nitrogen balance. J. Nuir. 82 395 (1964). 17.IIORWITT. (. IIARVEY. C. C.. ROTIIW'I.L. W. S., CUTLER, J. L.. and IIAIFRON.I). "rvptolllha.iiacin relationshmips in mni. J. Nutr. 6(. Supp. I (1956). I8.1FOX. IIAZE L M., FRY, 1). C.. and TOI.%ANN. N. MI.Isoluetcine, leicine and valint! mnterrelationshi ps in hiiamllm sulijects. Proc. 6th Intcrlatilal Congr. Nutr.. Edinburgh. Scotland, p. I I (Abstr.) l1963). 19.(GOPAI.AN. C'.. ald SRIKANIIA. S. (;.. Ltucii and pellagra. Lancel 1: 954 (1960). 20.1ILAVAI)Y. I., SIIKANTIA. S. G. and GOPALAN. C. The eflect of oral administration of leicine on tile ictalotlisln of tryntolhalii. Itiochlin. J. 87: 652 (1963). 21.1RAGIIURAMIULU. S. G.. NARASIN(;ARAO, It. S., and (OPAI.AN. C. Amnino acid inalanec and tryp0tll han-niaciii imctaho isin. I I ffcct of eucess leticine oil lie urinary excretion of try ptolhan-niacii inctaholites in rats. J. Nutr. 86: 100 (1965). 22. MIRTZ. [:.. [.. VERON, 0. A., BATES. L. S., and NI-LSON, 0. F. Giowth of rats fed on opaquii-2 inaize. Science 148: 1741 (1965). 23.GOPALAN. C., lIELAVAI)Y, !B., and KRIStlNAMURTII, I). Role of leuchic in tie pathogenesis ot canine black-tongue and pellagra. Lancet II : 956 (1969). IReceived February 8, 1971. Accepted Novetmber 9, 19711

Reprinted from CEREAL CHEMISTRY March-April 1972, Volume 49, No. 2 Published by the Ametican Association of Cereal Chemists, Inc. 3340 Pilot Knob Road, St. Paul, Minnesota 55121