Plant proteins. VI. The amino acid deficiencies in certain plant proteins

OndeJ·stejiOO'tt ./ounud of reteTinory SciencP ond Animal lnd11sfTy, T'ol111ne 11 . . Yum.lJPr 2, OctobPr, ]9:38.

Printed in the Union of South Africa by the

Governmen~ Printer, Pretoria.

Plant Proteins. VI.-The Amino Acid Defi- ciencies in Certain Plant Proteins.

Hy D. H. SM:(T'.L'S mHl .T. S. ('. ~tAlL-US. St>dion of Xuhition,

Onde1·~tE>poort .

.\.J.'I'liOl'l;u l he majorit.v ·0f the mni!JO ::t('id,; "·ere diRcoYered prim to 1900, ^{Yt'r~· limitt>cl clata} exist concerning their relahYe (li~h·.ibutiou.

Cow:e<Jllentl,v thE>re baR hec11 l.ittlt' nppl'e<"iation of tht' fact thnt tl1e nntritiYe YDlue of a proh•i11 depPJldt> upon the kin<l nucl quautiti<',;

of itt, component· <Ulliuo :J('id,.;. lt it>, therefore, not stupri,.;iug- that thE' proteiu requi remenh; are mo;:;t f!."t'llt'rally e"pres,;ed in tt>nn,; of anJotlllh; ot rlig·e,;tihlt' pr.oteill without nn.v l't'fert'Jl<"e to lhe clitl't•rt>nr·<""

in quality. Ho"·e,·t-r, the biological Yalue of proteins, as <levelo]lerl b.v M:itcl1ell (1929), takes into M·count tlH·' qunlitntiYe differen<'et<

existing an10ngst proteins, sin<'l' it lllPn,;ures !he magnitude of nhsodw!l llilrog-t•Jl actually utilixE>!l hy 11H" burly. lt 1s, tlw1·efore, a necessary m}(l est>ential measure iu tlte culculation of the nett e:fficienr·.~· ^{of different proteins for maintE'n}ance, growth, etL '1\w>

protein,; may contain the same amount of digestible 1Jl·oteill, tl1e onl,\·

<lifference heiug-, that one has u biological Yalue of 40 while the otht>r has a biological Y;dnt> of HO. lhsreganling qualitnh,-< .. <lifferen('e,; OJlt' ,,-onl<l fetod Pxactly the snme an1onnt of the hvo rligPstiblto protein,;

t.o c·ovE>r a specific neE'd of an rmimal. Ho"·eye1·, "·hen the <1m1.lity of these hYO protei Jlt> is taken in to consi<lt· ration, it i,; o In· im.t,.; t h ;\I·

only hal± the amount of digestiblE' protein of tlw latter p1·o!ein i,;

necessarv to fulfil the same hmdion ns the full muonnt· of ihe formE'r. ·

-WhilE' the biological Yaht(' actually i·ake,.; into acoount !he

rlefic·ienrie~:> of inrlispensable <llni.no aciLls in the protein nlOlectllt>, it does not supply clired information m; to the uatu1·p ,of su('h deficiE>ncit>s. Tn mcler, therefon•, to aceomplit>h ~:>upplementatioJl

ju!lici.ously, then•by enhancing tltt> qualit.,- of rlE>fi.eiPnt pmtt>ins. it lwcmnes imperative that the Hature of the amino acirl cleficit>llciPR prevailing in our feeds Rhould bE> determined.

r nforhmate]y llO direct ancl tmitable metho<l of rlf'tPnnining the amino acicl contenJ· of feeds is aYailable. Chemical analvsis is not only handicapped by labori.oufi, and in mrmy ways i~u·ompletP, methoflR of flet(-'rmination, but also by thE> fad !hat such fig-urPoi.

while indicative, haYe no actual hiologicnl ,;ig·nifi('ance 1.mless they are testecl out on animals. As a 1·e;;mlt thE> lllelh()(l most g·euendl~·

407

Pl.AN'l' PROTEINS.

em]Jloyed ts very inc1ircd and of the " h'lt mul 1niss " t_q1e, by \Yhid1 different ami no aci<ls tmspected to be <leficien t are inr:orpora ted with a protein and the effpd stn(lied h,,. differences in gTmdh response tU}(ler controlled conditions.

Hose (1\l;lo, 1H:'l1), through hi:-; e::densi\'1-' stuoies, h;ts iu l'eceut yean; considerably au gmentecl the existing list- of inll i spen saLle amino acids. Apart from threonine (o. amino (3 hydroxy butyric acid) no new indispen:sihle amino acid has been a<lded. HO\Yever, valine, phcnylabnilll', lenciltP ~1nrl isnlen<'inP, 11·hich have i11 Lhe pac,t LePn couRidered (liS]lf'nsahl<> are nm,· cbs~i{ie(l hy Hose (19>17) a.~

inlli;;pensahle, making Hte problem,; •)£ r.lt-d.ennining- the umin.o acid

<1efi<'ien('it>s in feeJs eYen more complicated.

A:-; far Lack as 1915 Osbome :1nd Mendel (1915) denwnstrated that Z-cystine supplements stimulaterl the growth of ntts on a casein containing diet of loll' sulphur. Since ihen many inYPsligit.iors haYe r:ontrilmteu ronfirma.tory eYi<lenee of the indispensability ·of cysti11P . .TohllH illld Finks (1H:20) fonlld tlu'lt thP addition of eyshne to uiPt::;

euntaining phaseolin markP<ll.'· improves the nutritiYe quality of this protein. Similarly Shennan ~tnd Menil (1H2!>) found that.

eystine enhanced the gTowth promoting pm,·er of ~Ybole milk po,nle1·

oYerdiluted IYith sbn·h. Mitchell and Smuts (19:~2), in their ,;tnclies on meat protein, showed that \Yhile :20 per cent. meat protein "~as

adecpwte in cystine, ^:1. significant stimulation of cystine ⁰¹¹ gTOIYth

tH'l'lliT<~cl when this pr·otein constitutes \l per cent. of the ratiolJ. 'l'he same workers (19;32), as well at> Shrewsbnry and Bratzler (1930), and Hayward, Steenbock anrl Bohste<lt (193G), fmm(l that r:y,.;tine was the

Limit~ing awino <l('icl in l:'oyabE>ans. lnd(eecl, so marked is the growth re,;ponsE' of r:tts io the inclusion of cystii'e in au othenYise adequate 1·ation that Shennan allll \Voods (1925) actually employed it as a n1d hod for quantitati l'e deterruination of this amino acid. Uecently, hmYeve1·, Hose (19:\7), Beach and White (l9~H), and B.:wrnstein h:tve pl'oclueecl eviden('e ::;howing that methim1 ine insteafl of cystine ic< the in(li:;pe>nsahle ::nnino acid. Such evidenr,e must await further ('Onfirmalioll, since it may be po,;~ible that ihE>se h1o ;uuino acids ma,v haYe n l'eciprocal function in nutrition.

B~· using Zein as the sole protein in a ration for rats, Osborne allll J\fenrlel (Hll4) dE-monstrated in a decisiYP 1nanne1· ihe iH<lispPnsa hili ty of tryptophane an<l lysine. The addition of tryptophane to such a ration satisfied the maintenance requirt>nwnts, but !.n·o,l·th \\~a . .; actually milv attai1'ecl ll'hf'u lv:>ine wns incorpontt.ed.

Several inve,;tiga tors found soya hectus (leficient in c~·st.i ne. Ho11·- ever, the supplementary effe<·t of this amino acid on soyahean protein

\l·a:s repeated, since the possibility existed that. all spe<·ies \\~ere not llPCPSSarily rleficient in cystine. Monis an<l vVright (1900) fmlll<l peanutmt>al c1eficient in lysine fm milk production, "'hile Johns :wd Jones (1917), by JIIPnns nt chPmical analysis, found no sur·h de:ficie]l(:.)'.

Consequently ly,;ine appem·erl to be a possible limiting factor in the protein of peamthneal. l\~o inrlir:ahon of any de:finit~e amino acid

<leficien(;y iu lin:-;eedme<ll an<l coprameal was available, so that c,vt>t.ine, the most easily aYailahle amino aeicl, appE-ared to be the most

re~tsonahle to try. The outcome of these different tests is reported belO\Y.

408

D. 13. SMl:TS AND .J. S. C. nHHAIS.

ExrERDLENTAL.

The protein feeds whic·h \Ye1·e of an average connnen:ial quality,

\\·ere fine[,\' gronlltl anU Jlll"'cd \\·ith the rest of the ingTNJients of th<:>

ration so us to give approxiwatel.v 8-JO per cent. of protein. The amino aci(h; were incorporated at the ra1e of ·20 per Gent., l'Pplacing- an equivalent amount of protein u i lrog-en. 'rhese aruino acicb were carefulh mixed with 1hr res! of the ration P•O as to ewmre homoge;H·ous distribution. The p<:>rcentnge composition of the rations is giYPn in Tahlt' 1. 'l'hC' pain•tl fec>1ling mC'tlw(l was usetl i·hrm1ghoul these studies. Tn some cases morr i ha11 six pairs of ntb; were Utif'(1, lnd ^neYer le:-<s. The 1 \YO nds of each pai1· rel'ei YP(1 iclentica 1 ^alllounh of food, the supplemented rntion in one ease ancl tlw unsupph·menled ration in the other. (\mtimHm,; record,; were kPpl of ali refusal,; of feecl, whi1·h JlPces,.;itnted a redudion in the ammmt ,,·eig-hec1 011l to hoth nJE•rnlwn-; of the pair. 11ats ,,-ere pairrc1 accon1iJJg- to age, sex, litter rtnd \Yeight. l<'requently rrtts weig·hing more !han thP l'!":]uin·c1 weig-ht (GO gm,.;.) had to bP us<·Ll dnP to searrit_y of rats. Rorly ,,-eig-ht,.;

,,-Pn' takPn 11·eekl.v ar;d the initial <1ll(1 final ,,-rig·h!s \YPl'P tlw <~HT<Ig'P

of ihrt>e r-on,;pc·JdiYe daily IYPig.hing,.;.

'l'be result,; of 1 he vai1·e<l feeding- c•xp<>ri 111ents an' summ;ui11ecl in 'rahles 2 and :~. A11y sig·uifif·an(·e attrihntPcl to trc><~tmenb must n a hna ll:v be b;t sed on the c1iffrreu r·es in total gai liS of pair m a tPs o ,-er I he· e)( peri mental period_ 'l'he si:o~P of tht•se r1iffereJlCes <lllrl tht>

<'Oilsi,.;trnc:v with whi(~h they appPar tlelc>rmim• the probability of the ('Ondusions that they favour. 'l¹he statistic-al analyses IH'n' perforn1t>d iu acc-onbnce ,,-i1h tht> methotl of Student (HlOS) for !hr int<-•rpretatiou of paired expPri111ental data. 'rhese calc-11lations are summarizecl in Tahlt> 4. The:· probability (P) is obtaine(1 from the ratio of the mean clifft>ren c-e bPhn•t>n pair nw tt>,; to the stan cb n1 <l eYia tion of difterPnC<'S and by the JmmlJer of observations. 'l'he Y<~hu· .of I' nahnall,v indi('Htt>s 1he ::;ig-nifil'<!ll('P of ille outeomP of a treatment. Heuer if P i,; P<lual to -01, ^{it may for} all practieal purpo;;es lw l'•OnclttdP(l tlwt the 1·esult obtained is tlue to the treatment applied and not 1o a fortuitous outoome (1ue to rhnnce. The g-reate1· P be(·omes the mon·

likely it is that the outcome is clue to chance alone.

The supplementing' effed of tryptophane 011 peanuhnral has been tPsterl out on 9 pr~irs of rats. As will be seen hom the,p n•fmlts tr_vptO])hane ;;upplelllentatiml had 110 effe(·t on the gTo\\·th promoii11g properties of peanuttneal, since .out of the !) pairs in the c·ompariso11 I favonrPcl the 11nsupplemented ration, \Yhih· only 2 faYoured the

supplement~·cl rr~tio11 iu total gains in weight. Iu fact, the probability P strongly favours the unsupplemeHtec1 ratimt, indicating- that the at1(1ition of tryptophane ha(1 in all probability exerted a drprP~sing­

effc'd on ihe rnlion.

In the c:rt,;e of peanut meal supplemente<l hy l,\·sinP uPg-atiYe 1e:mlt-s

\Yere also obtniut>d. Out of tl1e 11 pairs in the t·OmJH1rison, (; faYOlll'P(l the uHsupplementerl and 5 the supplementt•(1 ration in total g-ains in

"·eig-ht. 'l'he probability P .of -28 for the <·omparismls of total g-ain,;

is so large that chance alone mig-ht well haYe r1etPnnint><1 thp ouh·oJliP.

409

'J',\ HLE 1. f'e,.cenfor;e ('rillljlllsif ion of the Hot ions. ----~---------·-. ------·--· ------- l'~<tnutmeal. ....... . C:oprnmeal ................ . Linsccdmral. ... . HovnhPanmeal ............ . (\;stinc ............... . 'l'r·yptopha ne .............. . Lysine ........... . fl'o. i:lucrosc ......•...•.. >-' .l:lutterf&t ................... .

°

Codl1ver oil. ... . Han; is yeast ............... . Yeast Extract(1) ...•...•... NaCl. ....... · · ;\gar ...... ~ ..... . S;tlt mixtnre (2) .........•...... Stnrrh ........ . rrO'T'ALS ... . I'PI"("Cllt. )J ...... .

1. ]:) ·7 ]0·0 8·0 :2·0 10·0 1 ·0 4·:) +8·R 100·0 1·ii0

:2. :l. -J.. I :).

I

G. 7. R. 1.1. :~ ].)·7

~

-1

- ~.- -,. ~~-- ~ ~ ~ --

-I :l:l·il I

:u-o

-:!0 10·0

I

10·0 R·O 8·0 :2·0 :2·0 10·0 10·0 1·0 1·0 4·.1 4 ·.) 49·0 1 +8·8 .

·:!0 10·0 8·0 :2·0 10·0 1 ·0 4·<> 4!)·0 100·0

~ ~ ~~ ~ ~

l~~--1·+2 ==1=--J.=I=

10·0 8·0 :2·0 :!·() 1·0 :2·0 4·ii .):)·0 100·0 1·-J.ii

·:20 10·0 8·0 :2·0 :2·0 l·O :2·0 4·5

·:!0 10·0 10·0 8·0 8·0 2·0 :2·0 2· 0 2·0 l·O ! l·O 'I 4·5 I 4·ii 39·J . 40·3

.100-0 -/ JOo.o === ,

1-40

~- ~~0

100·0

:);) ·1 1·+.5

!). :2ii·(i 10·0 8·0 2·0 :!·0 J·O 4·:) 45·9 100·0 1·96 (') Yensi. e"trn<·t 11·as prepared acl'ording to th<• ml'thod of Hter S, Orellt 1•:. H., and McC'ollum, 1<:. \'. (.!. J1i"l. f'hr•m., \'ol. 108. Xo. 2. pp. '571-577, 1935). (") A moclifh•d Osbo.•·np and MPnclel salt mixtnrP de,c·ribcd by 1'. 13. Hawk and B. T,. Osler, 19:31. Stienu. Vol. 74, p. :~G9.

j_ ~~ -

:!fi·O ·:!0 10·0 8·0 :2·0 2·0 1·0 4·ii -!6·3 100·0 1-!)3

I

11. I :~:).:! 10·0 8·0 2·0 2·0 1·0 4·:) 37·3 100·0 2·0-J.

1:!. :l-J.· 7 ·:W 10·0 8·0 :2·0 2·0 1·0 4·,) 37·6 100·0 l·!l6

>-:; :.. !7. 1-i >-:; ;:;; 0 >-' l'i H z (/)

T.un.1·: '2. Thi' S11pplrmrntin,q E.B'el'l of Tryelojllinne, .l;ysi11e onrl C.'J'l111e 011 the Prolr'ins

of

Pea1111f. -----·---------·------~----·--~------~-----· ------·-------------------·---·- Initial "·eight gm ................ . ,.... Final weight gm ............ . """" Total Gains gm ........ . ... Tota I foO<l ronsum ption gm. Tnitial "·eight gn1 ........... . Final weight gm. Total Gains gm ..... Total f'oo<L c·onwmption P'm ..

8 p,,~ CE:\'1'. PE.I~l"I' I'RO'I'I·:r\'. l'ai1· I. l'air :2. l'.'.ir :!. l'ni1· -f.

I

l'air :;_ l';cir 6. I Control.

I

Trypto-1

Cont - r< - , 1- . -~- T - r y l-, t - o - - I- Co - nt r o l.

I-,J-'r_y_p:-

Cm~ -t t- .o - l. I_ T _ l .-y -pt - o ~ C~ n t ~ o l. l

Trypto-

~<~~ t ~-: - ~ -T -r yp t :

phanc•. , phc:ne. phnnc. plwne. 1 plmnc. . ph:uw. _________ , I ! I 102 1:14 32 314 Pair 7.

10.> 1:!0 :Yl 31-l-

!)6

uo

:2+ :28(j l'ni1· 8.

06 Ll:) I!J 286

73 10.:; :1~ :2ii8 Pair D.

76 102 :l6 2;)8 1

--- , Tn· Jto-, TIT >to-, ] T1· -)to- ( ontrol. "l Control.

I , ·

I ( ontrul. .Y I I phan<". p.>alw. 1 ph:1nc.

u:;

1;2!) :)(j 3:J(i

\).) 128 :l:l :~36

I ----· 80 I !)~ ]08

I

I i(i :28 2~- :~22 :{:!:!

I

7:i

I

67 10:2 I

1()0 27 :J:l :wl :{:!:l

7:l 10-l- 3::> 246

7:2. 100 :28 246

10.) 147

n

:343

102 84- 14-2 129 40 45 343 M:l

8-l- 130 46 :) ~:J ---ti UJ ... q >-l UJ :.. ~ ti UJ (")

"" >

:::; > ;-; •Yl

>!'-

,_..

~,:)

'1',1 !IT.E :2-(con I i11 uer/). 8 PllR CENT. l'EANUT PROTEIN. ___

P _ a ~ i" - ~ --~ -

Pair 2. _\ Pair :l. Pair 4. l';tir :3. Pai1· (L ! ControL

I

Lysine.

I

Control.

I

Lysine.

I

Control. [ Lysine. ControL

I

Lysine. Contml.

j

L.vsinc. Control.

I

Lysine. I Tniti<d weight gm ........ . ... 79 79 64 63 :)2 !'>2 49 49 7:) 76 ;)5 :)7 ... 130 1:26 122 11 :) li:Z 119 !):j !)4 13:2 1:22 110 118 ... 51 +7 58 ;)~ 60 67 +6 4:) :)7 46 55 61 ... 427 427 427 +:!7 .J-1:) 41:) 3:17 337 427 I +27 406 40fi I I

Final weight gm ........... . Total Gains gm .......... . Total food consumption gm .. Pair 7. Pair 8.

,,, , ,_ .I ' " ' '· ,

10. Pai1· ll. Control. I Lysine. 1 Control./ Lysine· Control.

I

Lysine.! Control.

I

Lysine. Control.

I

Lysine. Initial weight gm ........... iiO 52 :iO :)0 46 +8 48 47 63 60 Final weight gm ....... 66 6-'i 62 ()7 :)6 liO 67 :)9 90 SH Tota.l Gains gm .......... 16 1:1 1:2 17 10 12 19 12 27 28 Total food consumption gm ... 176 176 I :i I I :i I l:i6 l.i6 167 167 17:2 172 ----------· --- -- Prtir 1. _ Pair· :2. Pair

~ ;3_ __

Pair +. I Pair :i. l'air (i. Control.

I

Cystine. ControL

I

Cystine. Control.

I

Cystine. Control.

I

CysLinc.l Control.

I

Cystine. Control.

I

Cystine. 1 nitial weight gm ......... 81 71

I

76 7G 6:i 62 13:) 138 67 69 6+ 64 Fimtl weight gm ............... 106 91 98 10+ 90 88 170 17fi 89 93 96 10+ Total Gains gm ............. 25 :20

I

22 28 i.) 26 3:) 37 :22

u

32 -W Total foo'l (·onsumption gm ..... :160 360 :l:i6 :1:)() M2 3-l-:Z +97 +97 :n:Z 372 3+9 3+9 I --·~··~ ---------------

"tt ;... ~ ....; "tt t:;;:l 0 ....; l'j >-< z [/)

, I 'fAHLJo: ~J. ::;:; 'rltl! S7t[ijllementinfj Rfle<·t of Cystinl! 011 Rn.tions rontoiuinq CufJ/'{/IIU'al, l.insl!l!dm!!rtl and Soyabean111eol. Initial weight gm .. . Final weight gm .. . Total Gains gm .... . Total food consumption gm ...... . ~ ... CN lni~ial weight gm ... . Final weight gm ... . Total Gains gm ... . Total food consumption gm --· JnitiaJ weight gm ................ . Final weight gm .... . Total Gains gm ............. . Total food consumption gm ... . 8 PER c~NT. CoPRAMEAL. ---------~----------- P:ti1· I. Pair :2. Pair 3. Pair+. Pair :). Pair 6. ! Control. I Cystine. Control.

I

Cystine. I Control.] Cystine. Control.] Cystine. Control.

I

Cysti ne. I Control.

I

Cystine. J I

I I

I

11.5 107 7ii 75 162 172 137 13ii 47 65 62 60 512 512 442 442 Pai1· I. Pair 2. Control.[ Cvstinc. Control.\ Cystine. 90 97 102 10+ 100 :200 IS8 199 UL 103 S6 95 ;);};) ;);"");) 555 5;'i5

I

P<eir I. Pair 2. ---

S5 S6 79 79 ].)4 150 117 130 69 64 3S ;j1 492 492 405 40;i s PER CEN'l'. LI);SEEDMEAL. Pair ::L

I

Pai1· 4.

70 134 (i4 4SI Pail' 5.

6 ]4 7 48

8 1 3 I Control.[ Cystine. Control. I Cystine. Control.\ Cystine. 90 90 95 95 S7 88 190 187 IS7 19S JSO 195 100 97 92 103 93 107 531 531 ;ji)5 ;););) ;).:::i:) 5:){) 8 PER CEN'l'. SOYABllANS. Pail· 3. Pair 4. Pair •>.

73 114 41 407 Pair 6.

7+ 114 40 +07 Control. I Cystine. 97 100 187 192 90 92 5:15 5:).5 Pair 6. Control.

I

Cystine. Control.\ Cystine. Control.] Cystine. Control.[ Cystine. Control.

I

Cystine. Control.

I

Cystine ··-··--- I lOS 110 U+ 9:2 100 99 8~ S:2 so so 10:) 106 l:iS 187 liiO 177 160 17:i 120 1-l-!l 131 1+:2 10+ 17S ;)() 77 ;)() g,; GO 76 :l6 li7 :il 6:2 4!1 7:!. :{61 :Hi I :l61 :w I :!61 :Hi I ;{ii:!. :lii:2 :l:!O :l::JO :~fi I :Hil I

t:::l i:::l [/) ....,

""

d >-'

w

;... ~L; t:::l [/) 0 I.' ...., ;.. l:;j ;..

""

'/l

A

...

~

'f.<\HLI£ 40 Stat is! iud Nesulls of f>oirerl Feerlin.r; E'.rpeTiments. ---·-· Total gain iu weight grn.- \'lcan differences ''L .. ,o ••••••• o •••• 0 0 •••• 0 o ••••• o •••• o Standard cleviation S .... 0 •••• 0 0 0 ••• 0 o 0 ••• o 0 0 ••• 0 0 ••• 0 0 Hatio M/S (Z) ......... o •••• o o •••• o o •••• o Prob,bility (!') .... 0. 0 •••••• 0 0 0 00 0 0 0 ••• 0. 00.0 0 0 0. 0. 0 0 Comparisons of week!_,. gains in weight-- No. fa,·ouring su pplcmentcd r-ation ... . No. favouring unwpplemcnted ration ... 0. 0 0 ••••• 0 J\o. fn,·o~lring pj+-hpr ration ...

J>canut- mei\1 R per cent.

Copra- lncal 8 per cent.

C'YS'l'J~ E. Linseed- meal 8 fJPl' cent. -+ 2 -:l

I

-f ., -:1

+

7 .• , ~-~ 0·3 8·7 · -~l -.)7 l· I

--I ·1~7 . I IS

I

·028 -1----1--- J ;) 1 G .)

:2;) lG 1

:!G 1 :3 !)

Sovabean- "meal 8 per cent. f-:?2·8 7·9 ::?·9 ·0007 38 :) ;)

LYSIXE. THY.P'l'O· L'IIA~E. Pe-anut-

I

PC!tnut- meal meal 8 per 8 per cC'nt. j c-ent. --- -1·0 f:> • H ·] i

i

·:!S1

I

1----~

I

27

l

33 I I ;, I

-"2·7 ~-0 0·67 ·0~1 14 30 .10

~ :-- ~

'"' "'

~

s

~ >- '/. JJ

]). IL S:HL1TS Xt\n :1. S. C. )1.\lt.IIS.

'J'hi-; fin<ling- is not in agreement with that of MotTi:- anrl \\'rig-bl

(HJ;1:1), "·ho found pennutme:=d seriously ln<:king· in ly~i.ue for Jlli.lk pr«><lndion. H 011·eyer, it is quit-e po:=-sihle that milk productim1 C<lllH for an innease of quantity of this amino ncid so that J>~'nnntmenl ntay un<le1· these <·Pn<litions he short· of lvsi.nl". On the othPr hand Johm;

<lll<l Jones (1D17), by mea11s of chen;i.l'nl :JJlal)·Ri,-, fmJn<l no deAI'iPlll'.\.

of l.1·sine in the proteins of pranutmeal.

VVheJI j)P<IJIUt !Ileal i~ supplemented b_v cystine tlw lYStdt i:-;

negatiYe. .\ltho,~g·it :·J ()t ihe (i pain; sh01Y a g-reater total gain in 1n•ig-ht "·lw11 c)·,;tine is inl'orporated, these gains nrP not lnrgp enong-lt lo mnke tlll' <lifferPilCP shti"icdiutlly ,;ignifil'ant. 'l'he probability P i,;

equal to · }:)7, :1 Yalne whirh is far gTPater than thu :tl'ceptP<1 stnnrlal'fl of signifil'<lllC'P. F nrler tlH:'SE' l'Onclitiom; i.i must he coJu•hule<l tlwt l'hance nlone l'oul'l hnve pnHiur·e<l the outcome. 1f, hoii'Pver, pair 1 i.:; omittPrl tlwn r·_v:-;tine supplements pennutmeal sig·nific-:mtly. AftPl' our results ha<l been obtaiue<l Beach antl \Vhite (19;17) <lllll RaPmstein (19:18) showe<l th:d mt:·t·heon ine "·as the li111it i ng- amino aritl in :nncl1in, mte of the prott>iltR of pt•mml. Conaral'hin tlw otht·r prdPi11, i:; <l]Jp;lr<•nil.Y <·on1plete. HPnee it \\'0111<1 appE-ar tktt lJWthinnine is tlw limiting in<li,;pt>lhahle amino al'i<l in peclllutmeal.

lu Table :j the ,;tq>pleinenhtr,l' eftPd of eystinP on copntmt>al, lim;PedmPal mHl so:-· a bPn nmen l \w;, been ,;ultllll:n·ir,ed. Of the (i pairs of rats on thP c;opntllll':Jl :ulll copnllllPal :-Jll]Jl>lenwntPd by c,v;;tine,

:j bll'oured tlw :-;npplementPtl antl :j thP unsuppl<'lllentl'fl ration as I'E'ganl,; total g-:tin in IH'ig-ht. Tn thf' 42 \l'et•kly eon1pari,;ous of g-ain in wPight, rats, •On th<· ,;upplt•ntenh·d ndioJJ, gai11Pd 21i time~ nurl tho,;p on tlw 11llei11pplPmPnh•d r:ttion only Hi timp,.;_ Ho,Ye,·pr, the probability J>, thnt thf' g-rP:di'l' g·ain of the ,;upp!PmPnh•<l ntlio1t l1as been a cb:tncr m!lcome i,.; ·lJS, a ,-aluP :it'YPntl iinJp,; gT<•ater than the criticnl YaluE' of ·O:'l. Ti i,;, iherefore, r·OJll'ln<lt•<l that tlw <liftt'l'Pnr·e in toLtl :,;.tin l'aHnol lw :dtributl'<l to ilw dfed of cystine.

fn :1 t·olllJlnrison of linsee<lmeal 11·i.ih linsee<lmenl snpp]Pmented h)· cY:;t inP, ,-> out of the (i pain; fayoure<l the Rupp_lPntt·•nte<l ration in toLd gain. The probnhilit.v (P) ilwt ihi, diffprem·e in totnl g-ains is <hu• to <·hnnt·e j, onh ·02S, "·hil'h llll'<1ll:i t-lt:d tlw dwlti'Ps are approxinwtel\· :)4 to 1 that l'h:u11·e alone 11·onl<l haYe hmught about snrl1 a resnlt. Tt i,; l'lear, the1·eforP, tl);lt <·.n;tinP ha,; exPdecl a snpplemPnting pffed on thP proteins of liltS<'t>llmE'al.

'rh,tt <·:-·stine hac; a rlefinite, ,;upplenwntar:v pftpd o11 i hE' proteins of so_valwans is "~'ell frolll Tnhle ;). Of th<• (i pnin; in tlw test all respon<lP<l to treat"111Pllt of n ·stine :t111l outg:tin<•<l 11\· fa1· iheir pnir m:des on thP 1lliSllp]llt•lliPlliPd ration. 'J'lw proh:thilit,,- P thnt tl1is l'PRnH i,; due to l'hnnce i,.; P(j1'<tl io ·0007, 11·hiclt d t•arly demonstrates th<Jt this onT<'OlllP is l'Xl'lnsiYel:\· !hlP to tlw .indusion of <·.n;tine in the r:1 tion.

H.\· llH:'<liiS of n](~ pnire<l fe<•tliug' weth<Hl, the po,.;sihle in<lispeHsnhle

<lJninn ari<l <1efi,·iPncies of pennutmeal, copraml'nl, liltSPP(lmeal <tn<l soyaheanmeal haYe lwPn inve:<tigated.

-+15

PLAKT PHOTElXS.

It has been founJ that peanutmea1 is uot r1eficient in cystine, tr.vptophane or ly,.;ine, but may he in the light of investigations which appeared after the work had Leen completeJ, deficient in methionine.

Ooprameal is not deficient in cystine, "·hile 1 inseerlmei\ 1 and so:vabeanmeal are definitely deficient in cystine.

REFERENCES.

B.-\ E R~ST 1•~[?\. H. D. (1938). TIH) nutritive 1·a lnes of 1·a rious protei11 fra('tions of peanut. .J.B.C., Yol. L22, Ko. 3, pp. 781-790.

BI•;ACH, E. F .. AND WHITE, A. (1937). lVIethionine as a limiting faetor of arachin. Scient. proc. J..lJ.O., Vol. 119, No. 8.

HAYWARD, J. vY., STEENBOCK, H., ^ANn BOHSTEDT, G. (]936). The effect of cystine on the nntriti1·e value of the protein of raw a11d heated soyabeans. J. )hdr., Vol. 12, pp. 275-283 .

.JOH~S, C. 0., ^AND FINKS. A. J. (1920). The role of cystine in nutrition as exemplified by nutrition experiments with the protein of navybea n,

phascolns vulgaris. J.B.O., Vol. 41, pp. 379-389.

JOHNS, C. 0., AND JONES, D. B. (1917). The proteins of tlw peanut. J.B.O., Vol. 30, pp. 33-40.

:VHTCHELL, H. H., AXD HAMIL'1'02\, J. S. (1929). The biochemistr~· of the amino acids. flme1·. Soc . .llonograph. Kew York. 619 pp.

MITCHELL, H. H., AND SMUTS,

n.

B. (UJ32).- The amino acid deficiencies of beef, wheat, corn, oats and soyabeans for growth in the white rat . .J.n.c., Vol. 95, No. 1, pp. 263-281.

:\I"OHIU.S, S., AND WRIGHT, N. C. (1933). A comparison of the proteins of hloodmeal, peameal, dL•corticatecl earthnut cake and a mixture o.f decorticated earthnut cake and flaked maize. J. Da-i.Ty Sci., Vol. 5, No. 1, pp. 1-13.

OSBORNE . .T B , ^\ND MENDFiL, L. B. (1915). The compnrati1·c nntriti,·e 1·a lue of certa m protetns tn gt 011 th and the problem of protein optimum . .J.B.O., Vol. 20, pp. 351-378.

OS.BORNJ<J, .T. B., AND MENDEL, L. B. (191.4). Amino acid in nutrition a11d growth. J.B.O., Vol. 17, pp. 325-350.

RWH.\.RD, H., McCOY, CRUTIS, E. M., AKn ROSE, W. C. (1935). Feeding experiments with mixtures of highly purified amino acid. Isolation anrl identification of a tlE'W essential amino acid. J.B.O., Vol. 112, No. 1, pp. 280-802.

HOSE, ·v\T. C. (1938). The nutritive significance of the amino acid. Pltys.

Herietcs, Vol. 18, No. 1, pp. 109-135.

HOSE, W. C. (1937). The nutritive significam·c> of the amino acids rt!l(l certain related compmmds. Science, Vol. 86, pp. 298-800.

SHERMAN, H. C., AND MERRIL, A. I. (1925). Cystine in the nutrition of the growing rat. J.B.O., Vol. 63, pp. 331-.'338.

SHEHM.-\S, H. C., A:\'n WOODS, E. (Hl25). '!'he determination of cvstine bY means of feeding experiments. .J.B.O .. Vol. 66, pp. 29-36. · • SCHHEWSBURY, C. L., AND BltA'J'ZLEH, J. W. (1D:l3). Cystine deficietw~·

of soyabeans proteins at various levels in a purified ration and ns a supplement to corn . .J .• JgTic. HI's. (U.S.), Vol. 47, No. 11, pp. 889-89ii.

STCDEXTS (1908). Tbe probable error of a mean. Niometrika, Vol. 6, pp. 1-25.

416