REQUIREMENTS FOB VITAMIN C AS AFFECTED BY EXERCISE by PHYLLIS MAX CARPEHTER A THESIS submitted to the STATE COLLEGE in partial fulfillment of the requirements for the degree of MASTER OF ARTS APPROVED: Associated/Professor of Poods end Nutrition In Charge of Major <i'*iiiii<iiMiiii mfrmov.^mmmmmmmmm.m u+mmwm*>m*m*mit*iia,m^**m*+miimi0**¥+'m of Depcrtmont of Foods and Nutrition if«Mn^nnvn«<Mw^iM«^«««Mn|w#iM|Milp*' CheirmRn of School Graduate (eommlttec MPW|l*»' *'■ Piilliiij'i qatmim***** Ch&lrraen of St&t^Xollege Graduate Council ACKNOWLEDGMENTS The writer wishee to express her gratitude and ppprecietlon for the edviee and kind esBistence given to her by Cr, gfergaret L. Fincke, ^asociat© Profeeaor of Foods and Nutrition, during the course of this investigation. She would also like to acknowledge the loyal cooperation of her three exporimentel subjects and the Interest and support received from B^s. Jessamine C# Williams, Head of the Department of Foods and Nutrition. TABLE OF CONTENTS CHAPTER |. INTRODUCTION 1 Historlcel Background ............ Chemical Properties of Ascorbic Acid ..... Phyalology of Ascotblc Acid ......... Methods of Assay ............... Methods of Determining Requirements . . . . . Evaluation of Methods for Determining Nutritional State and Requirements . . . . Plasma Levels Requirements ................. Factors Affecting Requirement ........ 1 3 4 14 16 25 27 30 35 CHAPTER XI. PURPOSE OF •fHIS IKVES^IOATIOR .... 4l CHAPfBR III. BXPSRIMEHfAL ............ 42 General Procedure of Experiment ....... Analysis of Foods Used in Diet ........ Procedure for Determining Plasma Ascorbic Acid Level ........... Standardization of Dye ............ Stenderdisetlon of Sodium Thiosulfate .... Solutions .................. Description of Subjects .......... . 42 45 RESUIifS MX) DISC0SSIOH GRAPfSR IV. CHAPESR V. COnGLOSIOKS BIBLIOGRAPHY 46 47 49 49 50 ....... 53 ............. 57 LIST OF TAM1E8 fftbl© I. II. III. IV. V. Daily Intake of Vitamin C Requirecl to MointRin Tissue Saturation 40 Reported by Verious Experimenters . . ...... 33 Ascorbic Acid Content of Poods Used in Experimental Diet ............ 43 Daily Plesma Ascorbic Acid Values, Subject AR ........*••.... §3 Daily Plasma Ascorbic Mid Values, Subject LR ............... §9 Dflily Plasma Ascorbic Mid Values, Subject KD ............... 60 REQUIREMEBTS FOR VITAMIN 0 AS AFFECTED BY EXERCISE CHAPTER I INTRODUCTION Historical Baokgyotmel Scurvy, a vitamin 6 deficiency disease, has been known In history aa a plague, infesting armies, navies, and besieged towns. It was particularly common among the cruspders, on the voyages of oxplorstion of the sixteenth century, among the colonists of th© northern pert of Amerlem, and throughout ©11 history in the northern parts of Europe and Acis. The Greek, Roman, and Arabian writers do not seem to have been acquainted with the disease (55). It hes been known for over 300 years that fresh vegetables are a potent remedy for scurvy, but it was not known until the early part of the twentieth century that scurvy 1$ an avltamlnosis (36). In that same period, it was discovered by Bertenstein and, later, by Hoist and Frolich, that the guinea pig could acquire scurvy* that discovery opened th© way for aoiae valuable experi* mentation relative to the nature of vitamin C deficiency. Between 19l8 and 1925, Zllva was able to obtain almost pure antiscorbutic vitamin from lemon juice* He was able also to determine the basic properties, such as molecular compoeition (empirical formula CgHgOg), its 2 resemblBijce to the hexoscs, and its instability to oxygen, e ape c I filly in e.lkellne solution. In 1938 Szent Qyovgyl isclatea from rdrenBl glancis, fvom oranges, end from cabbage, a strongly reducing substance vhiefe ho edited "^©awonio aeii.'* la 193%» tfee identity of vit©iBia G wttfe jtoettt %©r$^i*8 "feeaaspoaie a^ld" coad ^itH ^il^a^s (,vedtteltts ftoetw* m& ii0@©yoi?©d by wsflpioae .gpo'ape' of ttOPkeFs, iiaao}.^ Hfeiigli sad Kia®* Sti»b9l.|r aad Sa©at -Ct^orgyt^ aad fillmaaa CB6). P&PQTB ^Ao fl»9t bf !feag^ ©ad Siag woap© baaod maiai.^ ©a tJi© ioola* tioa of ttosl* firiat ©atiseorbutio ersratals ia 1931. MeoMiag to Sing (61)* Tboae e^yetalc, obt&laed from lonoac, correeponueci ia t^pe, aeltiag |>oiat,. solubility, MtJ?ati©a yala© ©gaiadt ©sidi^iag and reducing agents, rotetion, electrical trassferonce, aad G -- 1 coabustio.i, with th© "hexuronic aoid'' which Sseat ^yofgyi h^d isolated as a tiaeuc recpiz'Gtory tmkQX from cebbsgee, oranges, and adrenal glcnds, at ®asabrldg© 0aiiireJ?©it|r ia 1^08* ■Zhevo seomad to ba no reasonable basis for queeticfilag the ideatity of tlie vitoiain after it taras deraoastrated ^hat Bte&dall*6 iad©p©ad©at ©xtraot frsaa ad^aaal glaads aM by ^a ©atlrely different pveeedove liad tfe© staa© antiscorbutic value ad the product of Waugh end King. Eeichstein aad Heworth announcea the first successful synthesis of ascorbic acid ia 1933. 3 Chemlcel Properties of Ascorbic Acid Vitamin € li®$ aa acid fresottoa, %%t& |>rop0j?ty beiag doe to an enollc hydrogen (59). 'Tbe most algnificent reectione ere those which involve oxidation and reduction. fixe oxidstloa of aseofrbic aoid 1& gteatXy ©ffectod by verlations in pH end by the presence of catalysts, euch as cupr-ic, ferric, raorcuric, Gilvcr, and mongar.ccc ions. T^e vitaai© is j?©v©l?0lbiy oxtdiaed by a g»eet many rcfigents such as methylene blue, qulnones, the 1' dophenol dyos, hydrogen peroxide, and iodine. In cqueous solutions,, the mt© of a$j?©bi@ ©xldatloa %■$ increased by exposure to light and by the pi'ceenee of the hemochromogens. The oxidized form of the vltrain, dehydroescorbic acid, 18 falply atabl© la toUtatloia belot? pH^, bat la more alkaline solution, another strong reducing substance forms, which on farther oxidation gives rise to oxalic acid and 1-threonlo acid* Reduction of dehydroascorbic add can be brought about by hydrogen culphido, eysteina, acid the "fixed - SB" groups of p^©teln0* It %m boon found that glutpthiojuO in the tlcimes may mt as a protective mechanism against oxidation of meoojpbic ^dd by <a©pp©i>» Accord- ing to Becker, ascorbic acid is considered the ooonzjme for glntathione oxidation {6)* f^o of the eneyiaes which ©xldla© and reduce ascorbic add respectively, ©an b© separated froa cabbage juice; the reductase has been found 4 to be much more labile th&U the oxldase (22). Phrfrioiogy of Afeorhio Aeia When aecorbic acid ie withheld from the organism, the main changes that occur are in the intercellulfir substances surrounding the cello which stcrt from the mesenchymal or middle Ipyer of the embryo (24). normally the flbroblast, or the basic cell of fibrous tissue, forms email fibrils in an pmorphoue ground eubstEnce, the fibrils being gathered together Into wavy bends of collagen of1 connective tissue. In normal growth, the fibrila Appear to he cemented together by a translucent ground aubstance; It Is this formation of intercellular materials which is probebly controlled by vitamin C In ocorbutlc guinea pigs, the fibrobleets and the ground eubatance ®,re present, but the fibrils and bands of eoll&gen do not eppepr; when the animals are treated with sufficient vitamin C, the collegenous material appears in eighteen hours. The formation of the Intercellular substance of teeth (dentin) end of bone (osteold tissue) can he controlled in the same vay, by supplying or withholding the vitomin. The bony lesions In vitamin C deficiency are most eommon at the costochondrcl JunotIons, the distal and proximal ends of the long hone of the thigh, and the proximal end of the tibia and the wrist (26). It appears that, when vitamin C Is not present, the osteoblasts return to their primitive form (flhrohlasts) and try to form a fibrous, rather thm ?- bony, connoetIon, between the cpiphyuis find aicnhyuls. This abnormal {son© is called the ^gerufltwMrtc* «r "ftpiaevwie ai®i?rot(r,." ■ir&tcti id tfei© i!k 4ofiei©©©ir 0? vit-Qsaifr 6 i»©smiti. i<i ©tenges ia th© te©t& ond gums (ii#S5*)* ^©s*© ai»e e3i®3ag©8 in the pulp a&<3 &^ntin of tho teoth, nna 'virinflaiffi^tioa of tho gome Pdealtd* ttta©!?' soytft of t&© bod^ Qtiiefe may b© sff©ote4 ^y asoopbie a* id 46£l«leitty «po tla® ©f©s (15), tfe© i©si© adwov ($3)* «®& gla»fiai©r (83) «ttd saa^el® tldoqe-{lO)« I3©et leaioas of soyo?^ osia b© traced to tho loablllty of tu© aoeoiudg^aal oettt to fo^a. isappopliag oabsKfiaeQ* ih© typitioi issioa of ©#©&tir is tu© pe^ifoilioulap p©t©©tei#i h©a©i»Pb®@©* fh© p@t@<3iiia<D ay© most eoaii©® om tti© logs ©F ^©?0 tbef© is prtennvpe m th© oafiliftPiee. Cramkm, Lund, cna Bill (31) rceaatly co^rlbuteel a, vfeintebl© e^aiF ia vltami* Q deflei^tMijr. ftoeiir 8©b|©®t, toaftdon, tsra© o© a diet f*©© fpon ir©g©t&bi©si t tmtt®, end Okillc fflp sbout 6ix Eioatlis. At tikm ©M of 4l d^f9* ftio ■ plftgiiaia %9V9X of ©sdofbi® ©eld' »a» eevo* $h© a.aoo»bl© aeid content of tfce wMtoi-oell plat©l©t blood fyaotlo^ foil to ■aep© &ft©p. 83' d©js* §a th© 13^ti^ day, Ssnall pwlfolll^n* Iflup papaleQ appeefltod o9©x» tho battodtes and baok^ of tlie ealtr©©.. !J?h©0© papal©© fcliey e©nsld©r©d to b© tike flffet slga's of mmvy* ?©s»lf©lifoi|ilik5p ^©iio^3?li§ig©0 ^.ppemfed sft©f» l6l days., %©a tb© 8'«b5.©#t va© im tb© deflelent '6 state, c>n incision was made across tho lurabas? region of the beck. This wound foiled to fcecl until the Recorbl© a©ld 8«ppiom©nt was givea* ¥iiifl©ia aa<a Srvtia (47) Rdvise thet t|i® plasma escorbic mi4 and the serum protela levels of patients fee brought to ftOJPm&l befor© ft^gery* men vitemiD G rioh foods ere eKCluded from the dlot, & vague condition of general poor health msy result (69), the state often being eceempenied by anemia (^,66,69). A deficiency m&f fileo be Bccomppnied by a loworeci reoietrnce. King end Menten (60) found &, definite loweri^ of the reeiBtenco of vitrnin 0 deficient guinee pigs to liajecttoas of dlphthei?!^ toxls. Florl (3$) demonstj»at©<i thst ascorbic acid alone or with extract of adrenal cortex hpd soffle detoxlfTlag setloh is vitro ftgalMt diphtheria. It has been suggested that a lack of edequete vitDJain C may be the oa&se of hyperaenaitlvenese to certain foods, particularly as it occurs la iBfaney (91»li2}* There h^s been some evidence presented (82) that a vltsmin C deftclenej say lead to respiratory ahd other infectlone. The effect of ascorbic acid deficiency on the reeiotrnce raechanisrae of the body is hot known. It is known that there is eoiae relationship beowoeii asoorblo acid and blood complement (68). It has been found that there is a drop in the complement tlter of the scorbutic guinea pig and that the value rises when vitwain © is adaiinistered* 7 aai QbeppwA {7Q,®2) torn® fhBt with vt%m±ti © QotMoMf tfo®ve 1.9 6 X09& i© ipeie^t> nhioti is oafetapfcntftd Ijy AB. tiomtisY, .iJ©a^®a,' aa^ tins Cl^) ®a^© easnteaisiv^ liietol©* aid of iitv&t nlt&etie m& f*t st&i&iag n&tefialo epsltei ilredfely t© fke tiisstt©©* ffeej' FottttAsttnt t&© siiv®^ t/ep© oa a vita^lia C?' fre© ^i^t*. I© tsli© Sfeo^toutie guises pigs, tbey »©t©i tls© <lliia|KP9ei«Me «f .f«t ntdialag • mateyi&t ftoft of ^oobSL^.^ftfa^tiird ©belest©!?©! fi?©© ^© (aflpoiiai. do^tsosc* Sbef $,%$& foiind ffet^f ddgenei^a^ltMb itt pcrto of the nyocLirciimn -cmi lit ol:oIett\I aut;clc as veil m $&%%$ tnftltPBtto^t m^ t&btif 30ge8e*&tl0ft of tte li^ea? aM ct)n©':>inico ccngostica of the iivc'rj tmd homol-'^hf.ecE. MiiTRlrerfli (73) found that In guinea plga i'ed on & diet deficient in vitcnin C, fli@ pigraGrit Gr,crotiiio J.'^KCtio^ of ^&e iiws» snd fc&e o-speoitr of Kto liv©x» fos? da* to'iifyine ii@€itti!i GGntonlaun fend iiiuolo wore ieere&aeS* •Jbe oxidafci^o rerotionc ci* eaoorbiC acid stggo'St that the vitsolft se^" pi&5r ©a iiap©^t.©at patt ia ti&tttse i»'©spiip&* ticn. Keliie and Zllva rop&Ptoil tiict EriTiaoii found ?in 8 uptake of oxygen by liver sliceB of scorbutic animals wben vitamin 0 vee added (56). Kellie end Zilva were able to repeat the experiment and found that the eddition of ascorbic eeld to liver tissue increased the surviving respiration even when the animals were not scorbutic. They also found that the increase in respiration was less in animals on a normal diet than in anim&ls on & diet restricted in calories or in ascorbic acid. In further experiment;), they found that the surviving respiration of the liver tissue of 95 pev cent ©f their animals on a diet restricted in calories and 5% per cent of those on a normal diet was increased by the addition of ascorbic acid. The great reduction of oxygen uptake which was brought about by phloridzin, inhibitor of phosphorylation of carbohydrate, suggests a connection of ascorbic acid with any one of the stages of carbohydrate catabolism following the tep of phosphorylation* Stewart and Learmonth (93) found that ascorbic acid injected into cats which had been bled to 50 per cent of their original blood volume would, In some eases, prolong their lives. They suggested that the action may have been due to the increased supply of oxygen to the tissues by ascorbic acid and even suggested a possible practical application of this phenomenon to human sub* jects during war time. 9 Other biochemical funetione of e corbie scle have been auggested. Robertson, Ropes, and Bsuor (83,84) found that ascorbic mId would reduce the viscosity of mucin in the presence of hydrogen peroxide* With further experimentation, they found that it acted on polyaaccheridos auch ae starch, pectin, flexseed, mucilage, and the polysnccherides of synovial mucin end cartilpge and that it destroyed the capsuloo of various types of pneumoGocci. Leter thoy brought ©bout the in vitro dephoaphorylation of /^-gljreei'o^hoophfete hf aecorbic ecid and hydrogen peroxide. They suggested that a possible function of ascorbic acid maj be the degradation of mucina ^nd polyssccharides in physiological and ppthological proceasee. Itoggle tind %nd (77) suggested that ascorbic acid mcy have a role in protein aynthesis when they found that the ratio of insoluble to soluble nitrogen in the leaves of cereal grade increased with increasing amouiite of ascorbic acid. It has been found that ascorbic acid has some function In protein metabolism* In 1939, Levine, Harpies, end Gordon (6k) found that certain tyrosyl compounds (1-p-hydroxyphenylactic acid and a keto acid which they believed to be p-hydroxyphenylpyruvic acid) were excreted by premature infant B. They found that the feeding of the aromatic aralno acids to these infants would increase the 10 At 6bo«t tfcft sass' tSisdf S©4l0#k and Siib©»©:t©im tof f#©4i®g ritenitt 0 4te'#ieient gtiia©s plgi I^POPIB^ ©^ feoAtog of tte vitamia* m&immi (88) f»aaa tint fecnogeatiale &©ia* alpha, koto g«ti»«|ft pig© ^h©^ ©itfeep l^sKkdaylaUitfttfi ©^ ^m^ipf^mle a@ii was giir«ak Wfeea ©m© of tfe© a©t^ollt@©, jMtytfsoxjr* pfee^flp^^tri© ^©idj wi.8 gltr@m^ tfe© vltttailtt WB fouai to h&tf# tltti© ©s» .ao effeot m the •iMWoeAtttg oetaboliteo* ■ ftras %lkl0 WWijr oowil^Utoa tlttt tfte ^©iat #f attaek of tSi© titdaift ©»t ©iai»© ddldt notftbelitsBi i» oenfieod'to tins, early •tage»# •ey«r (IS) ira$ ablo t« pyoiae© th© laaetl^tio^ of »ityo> H@ ofetfei®©4 up to a Si p®? eeiit yt©!^ ©f ©saaoaife t»l0E ftis» i»£6 bufebi©€ tfapoegfe a. mtiem& ftolmtioa of. ceeorbic f citi end eomc rminoa. He G^BC t'cnmd a (iecreased ©2&cs?©fcl©m of osg^otttaltio by Aoge vtaon t&^y we»« give® '82 to %O0 xag. of asoorblo aeii. 11 Bourne (14) nee suggested &%ilt another function of asooroic acid. Be pointe out tliat ascorbic acid ie located in high concent^ciiion la the region ®f the Goigi apparatus of biologically active cells mM tli&t the Golgi cppai^tue ig yecogniiied as the syn^I'etiic centosj of the cell. He concludes that ©sCGrbie acia prei>ably has some function in the s/utheeis of chemical tjuhataiioesj lie gives at the most likely explotifetioii that the presence of escorbic aoid fotmm Im %&». ftT&t&ofeie elates? of %hs> oel'i pj'oaiaeit ft©® %Qi®$ m0%®'b®%l&Q& as deea as fosis®^* f|i9'-pela.tioiidtilp of ©se@pMe m±& to opeelfltt toFffioa©s a&d. tfttd^adfi has beea itMi^fi -in a^a© l^©^^®?!©®* ^os»® is ©©a© ©;t?id©m©<s' ^Siat ®1©' *&fc6&tfe h&@ ^s aati* fetjirolj^opi© a©'%l©a, hn% tli® r^lati^aeii^ iA9 wit b©©a -ftigift} e»d-Siiig.f93) ?otts«S t&at tfe© g'la@@s# feotaparoe of giiiaea pigs ^m defiaitsly 1L#^@TO^ bj p^ogf^ssiv© ®86©3?l>i<? e^lS :i©pI©tiosj» p©lati0iaaiip b©tti@©ii g$tio&bl$ a<si€ aM fott? ©a^fsa®©, %wo fefirot^ie am<l t^r© feapimton'y* #«P tito stvfl^ of tl© ji|rdi»©l^ti.e- amsiiita©©, tlba tlsfifioo it$e4. x^oipe tftentoted with of tto s?e©pi:sa,to^sr onts^o^t) WJP© s^Mio^i % aoefiiKPlag ttoe 12 oxygen or hydrogen uptake cf certain tissued in a. unit, time. In this study, they found that the liver estersse activity of their scorbutic guinea pigs vas one-third the activity of the normal animals. They found that phoaphatese activity of intestinal raucoae and kidney cortex showed a moderate decrease in scurvy. The activities of the two respiratory enzymes es meseured by this method were definitely lower in the scorbutic animals* The pctivity of succinic dehydrogenase in scorbutic heart tisane appeared to he SO per cent lees than that of normal tissue and 65 per cent lese in scorbutic skeletal muscle then of normal skeletal muscle. The activity of cytochrome oxidaae in scorbutic heart and skeletal rauecle was about 45 per cent lover than that of the normal tissue. Harrer and King (42) suggested that ascorbic acid may he important in cellular physiology aft a regulating and proteotlve agent, they write ai followst "By protecting active groups such as R * SB (1 being a protein), relatively small cmounts of ascorbic sold might aid in the regulation of major hydrolytle and respiratory systeas In the tissues without entering directly into the reactions concerned." They point out the apparent paradox that although scurvy is eccomp&nied 13 by total inc^OQaoa body ^©apl^tslom esd Ind'eaoed Fed* pirotion of tissue ollces, there t$ & distinct decreftse ia aotiv&ty of ttro- of t&e s»s.j©? t?'®®pimtQ$f m%fm&* ■ - ^e vote of seootbi^ aoii ia tfcd sietaboiio pffoaesaes of plftirSo and aaim&lp Is not oloB^ly understood. ' Thove le pi»s0ti^all,f »o asco^tol© aei^ to ^© found ta 4>y seois, trat tfe© vitdtt&ft afpe^p0 vlievo ti© 0fi?otitiag. pvommm &?e ^pes?®ati|' laitint©^* ia § few feoit^s afte» 'tite «©©d is a©i'jBt©a©d* 11 is foisaiS iii Mgh e@ii©©Bt2?©tl©ms la %!>@ a^^lvdty ii»0ulag' pi^ts ©f tla© hi^Si©^ p!Uat9^ aM ia all f5P0.3& p>©©® ldAire«« la. the mijml ofrgmtm ©seos?^!© a®14 is forma ia t^a greatest aoncsatratloao la the tldftttee of g3P©et©fit detivitiri tUe pituitel^ boiy geae*filly Si^s th© ^©atdet c©i&@©at2Patt©a a®^# ia ^©a^ea^iag ©fi©^,,.' tli® w&ptte lat©©!,,. @4j?©aal ^©ftex,. jroiaig tlipiu*, livep, @aS bi'aln. The presence of the vitmain ia. tissues of hl^hdfirt metaboli© aotivitf ia€itiat©i thst it nftp have sa ©©©©attel aetabdlio I?©1©> Hi$g (6i) states $ "Slie high oonceittrctlC'sa of socoi^bie ecid la. glsadular tissue a ia€i©st©© * 4»$p94 ©f ©o^TOlatioa »ith th© $®mp&% #®t© @f tt&tdholKust aiiftlQgotts to th© ^©latioaship ia pl©at0♦,* Kei^om'inri (52) fouM that ia blecfl feept la ^a ctmcsphere ©f :altF©g©a> th© plaeia©, ■©so.oi'biO' eoii ©at©i*©4 th© ©ella pt .room or body temperature but not at low tempes-'aturee (7 d©gj»©©@ ©©atigs»M©)» ■ FiPes! this h© ©oaoia^et th&t th@' 14 transfer Into the cells Is probably aaBoclcted with some metabolic process. Methods of Assay The eerller assays for socorblc ecld were mede with the uae of the gvilnes pig, both by the preventive and curative methods. Another method that has proved to be very useful la the "guinea pig tooth method0 suggested by Kd'Jev* la whleh the degree ©f aeurvy pyeeeat 1$ d&te&nlfked .hy #hii.iigeS; 1® the st^^tos*© of the (tsfttlm ©f the. t©®th» I'llLlsieii.e p Sissiohj suS Hii'-seh ftJPSt developed © iidthodt, JP©5?' .(Set-^urolRlu^ .the ^vese&o© of s?©<Slui©e^ fts^ofbl© aold iB; hlo©^?- ^helip. ffieth©^ wafc hase^i ©& the tlt^atloa of a t^lshlo^sietld fe<s:i€: tl^tJP^te, of blood ^l^Sffife Hlth ■ the d^"-® ,@ ,6, di^hio^^hetiol .Itidlopheteoi* IpEieri©; «ttd vaa l<s&eleB, ©tig^ested. Feduciag, th© as^oFblp aold ^etesat.iin hXo©d plessa vifeh hytTO^en,. 9ttlf Ide. end. ^eeifitgitlag': lateyferlBg' s^ucisijl' .^^biatsBces ■«aeh. ^©'.itsyateim©,, with seiwivl* s^et&t® fS®)*. .fhls sjothod.-hs'e-^yev^d t® he y^th^j? i[ii@e3?1lal9t^ sts It Is a©d©.s.8$jp.y to ^©©©ve the hirdpogeh sisl.fl«l® c©a®letely tilth alt&©'g©a !&■ ©fdei? t© pi'eireat ■ e^©©0i$ i?©dis©tl©a' ©f the dye* Wmm&w :m& Aht have ©©dlfled the ©Hglh&i dye !>»»©•■ 6©dii9e. ©ad have adapted It t© the ise® of veK'y small ©aaoasts ©f. feldtd-*. S'hey "$tigge$t©d using addton. twogatote @M!&t, lat©3?j .raetapho^ph©^© a>©ld». &# pi?©t©lsi pi?®©i^l* te»t» (>®K IS potfeaslui^i cya&ide end potaoeium ox&l&te to prevent the c^idatioa of eccorblc acid In drawn blood samples (79)Other vorlcei^ have f^m^d that there is BO gro&te? loss ©f iaseo^M© mi& vhm pote^eitni ©f&tal#6 ie not' fe«ld©«J and that ooaie lots cf the CG!^ Ve®±m& oth®® reageatg tou-i to dacolc^l^e t^® &B&Q ho&n aaggeeted for as* e®i?tei® acid ajaalfsiSi -among «lai©|3t a*d f©rs»oef®ai^®, pMos^feotungatl© acii^ ffi®tli^S.eB© bl-^e, sad flioafiiosolfMio p^ovdd t® b© mot ©ati^ei^ saiilsfs@toJ?f* A epeets^* ©copi© ae-tkot <md & prsteoiur© b&«&d om t^o «so of «tid&* tioa*r©<lwttom tie QSQ *IBPW-O MV© b@©ii doggested* 800 smgg©S!te<l of SHo ^oaott®a botueea s^Ilim© oaotate aad f«^fa£»sli ^M©^ i# foHE®i »©« 68«oybl« a@ii 01& f&a&tYs^io^s 3pot©iiti^80t^le aoifttedd fe&vo b©©B t^iei, btt* ajS^il so^.p tfeofi:© to© b@©*i vor? Uatl*©* ia wtmlHon bmmm- of ^iftiEg p©t©stt4l'# m® MAt&ttmt ©mi-points. B6s^i6# ^psom*. m& Wang (44) feave reoe^tlsr iat^oi^©©i a ®0tla0i for dft- $le$t2flttet»to ©lalftlt witli tSi© us@ of a flatimwB et©et3P#a© ©mtot «lt& awS'ftttSfy* fho ©©tfeoi taa^ ^IPOV© t© b© a us©fmi on© f©# vdattaa saatjreia* from 16 MIndlin and Butler (/2) imve adapted the aic^o dye met bod to the photoelectric e&lex'imeter. Of the meny mic^o iaetliofia tried by various workers, the indophenol titrBtion method ae modified by Farrcer ana /ibt and tit© colorimetrlc metiioa of Mindlin aai Ittlet Mve been prefeiTped fey the greatest noiahe^ of «wk»#&» Methods of Deterralnlng Requireaecte the fir at attempts at messuritig hxmzu tequii-emente vere raatie i;y C^tiiliu in Bt^QdOE la 1931 * li& method way to tlad the saallsdt caoaat; of o^&mg® juieo whie& trottlA ^©x^eet © 1099906 e&pil^tey jfc&%&$6M®t a condltloa vhioh WGS ^evoslod ijy goiocaiao a^poari@g tihen pmarnvQ va* applied to th» as?a (?7#-38»39)* S^io method has beoEi ps?tl7 ivplacoci ay a *3@tk®i iiit-'odaGoa % Dallclorf, vhoreby aagativo p-?ossii^c is appliec, t^ aa ©pea of the avm and tke tiu^aba^ sf p^toaliiao oomt^i (9^}« Ha-^y «03Pkefs sin®® <|$t&ll&*e ®xf©3?lia®ats. to^o pel?* formed have found no GQWOISXIOU hQtii$®m o^pillc.^y i»e®l*ta®o© aai astritiohel et&te (il3*7S,4^#as}» Ae«o»d- ing to (iiJthliii, the ^e&fioh %hat th©@@ uom-si'e Mave found no sucii coiU'elatifcu t& thrs'c the ^etho^ is mot Gpo^xfis when jpl&sqi© levels are Kuck above C.l pg pm 100 ml anfi th&t ii* the oouuttles v^iie^o tiiosc o^pstieciA'ic ha.vc I/^en eavsled oiit. (except is Sweelea), the ©wi'a.g© &i®% ia e©m» pai?ativel>' floh in vliesiiii C, af>d plaism '^ilnoa GG low 17 as thet are seldoni found. Dalldorf hse made extended studies on tit® method, using his negative pressure technique, and ia of the opinion that the method will ^ive dependsble inforraetion on the presence or absence of vitamin $ deficiency but does not ahow the degree Of defioiency. Dslldorf has found th&t the method yill give f&tti®%f neg&tlve results when severe anemia is present. Sloan points out thet the tHioMeat of the skin and the position of the arm also affect the There is some evidence now that lowered capillary resistance as shown by these teat® may be Sue to the leek of vitsmin P (65). Subjects of Levcowich and B«?tcholder had larger peteehiae when on a %W vitemin C diet supplemented iiitfe 4& to 120 mg of pa*© ©soofrbi© acid th&n they did when OR a freely chosen diet*. In 1937, Hotter introduced © direct teat for deter* mining nutritionfel state (87). Be injected a small amount of the dye 2,6 dichlorophenolindophenol into the foreprai of his subjecto, measured ite speed of decolorizstion, and concluded that that epeed wse proportional to the emount of ascorbic pcid in the blood. Othere since then have failed to find such a correlation (So) end advanced the theory thet there may be other reducing eubstancea in the skin, which would interfere with the test* 13 In 1932 Tlllmens announced & relptlonahip between the eecorbic acid content ot food and ltd ebillty to reduce the dye 2,6 dichlorophenollndophenol. Lster, thie principle vm applied to the measurement of cscorbic odd in urine. Since then, aoms progress hae been nede on the determination of mlntniua end optimum requlremento for verioue nge groups* It h&s hem shown by Harris and ©there that tsio tt^iae^f mm®ttm of Adootfbio '&@i^ id roughly ppopo** tlotis.1 to, the-iatake &t oertalm X©tr©Xs (4f^6y$$«74)« Johnson n.ad 'iilva (33) found that the excpotiioa dopeadB i©th,afot''th© ia6§iiiti^e ofth^ iatstse maM upom the degpoe of sfcturattott of the subjeet^ a aach amall©?-,., l>9&Qomt®§e of a siftgle laege dose teelag ejco^etsd if the 9et»V99t^ of the gtibj©at hatre beeat pr^tirioutlijr de^lete^i*' < For e, titao aa attempt uac m4e to aa^oao nutyitional 9tattt& hf a©t©Kiiaiag the iirias»y ©s©^>tlOBt of ascorbic mid {45»11?)* the tevet of eso^atioJa «ow?e$pmtfias to the ^louier' Mialtof ttonaal" hat heeh ©et at appj?03S.iaKitel7 13 to.^O- ag by verio^t vtiv&epe (43#iiSf3tj# Sdi»l9» Bey,, ^h^ VafNl, aad Ahasi hsire d^tia^tod that th© ^©ruge dfiity ex^rettoh fofc 'horiaal a^hledtt lit ^'bout 30 gig ('K>,3). Hfi^ie ©ni Abbfvay (^3) fouM tha'i a*ii intake of 25 Big of aacorbic sold would reeult In ail oxcrofeion of 13 wg-* oa© suhleot of «roh»i©a ®sd ztlvft (M) «a*»#»od i9 80 to IS© ag ©f aieoovblA acid «k©B h© tfeggi&tfijr tiaelutod is..hie dfitl^r «li©'t fcti© ©r^ages b©tid©8 g^een ^©getaW©©* • It -fee* toe©» #&©«'© that there is a tti*©mi tfep@'sidiaw v&ioe o^.&'definite «s®6e'©otrfefet©n la tii® btooi fet wMcia feseoFM© ■ &$!& .begieo t©' spije^x? ia the w^ia© ■ ia iftrge siaoitte'(Si>B.,51*l4.}* fhlfi iwaat' thseiChoW tm*!©© fe*1 • Alffereftt iafilvtaisle, .bttt th© average a^p©©j?e te he about &.# to i.4 ffig pev.idO al of bloei ptiift&u Mm& the tii©e^©e' hoe^aie "eatiwpated* ?lt& the intfilBe && Mu£6eiit|r stoip®^# the ^api<ilir> ggnetl? hy the eettewd' tef, XetteV-ett&e&t?? f®iM ia ^he Mh|Q©t 'a&ee^h&e aelfi «i€ ©sereti©^ d^ep^ ve»y te the See festiisg oa s f^otly ^kosea dliet (55)* - Jdui&en .acid 2ilva (55) gav© vitanta 0 4efieleat dtthjeetft gvedoally i&e&eA&lag Aeoeo of atieerhl^. aei4 amS foiaiUI he ©igaifi<&©at rifi© in ®*6&etie& .until the Deventh day* ®3s® «©©aat ese^teted ^PMmeiilf roe© until the «e$etofcee%th day» ^h©a a eornGtamt l©^©! wo ffe&eheAt this pelet- they ee&ftKtered t© b© the level' at ohieh the tif0^©0vi!i» esttti^ted *lthi 1$B® vltsals* H©i©©ffiaiiaif tjfaa W0^0eh> ©ad t&a B©Ml©a ha^© attor^pted t© aesoei*©' th© daily e^peoAituye '©f &e®optel# atid;.; '"(50>.$l}4> -'Jft deeerlhiftg th©iP ^etlMdv th©y fttyy- .■•.••■ If a .pvetrlettily. £attg*eted ^bleet.io^ ..■.•..s reaatrir'ated efter hpvlng omitted all vitamin so C tov B certain length of time, the dose of a&eotfbie aoi& ve^Bi^ed t© produe© sat^©*tion corresponds to the qusntity tided from tli© body etefee during tli© irltiMiia 0 fjp©© period* Consequentiy thla emount w^ien divided by tii© iitttabol^ of €sjr®- %%& ©atp^^issoot lasted, csn be conaiciered as the cieily expen"Satwatioa" is tteei* ©Kp^ftaents Is o©a§id©f,©d to be th® condition when eonsiderable portions of & tost close fii© yeaponto to a /rtt©st d©0©w of feooo^bie soli liaa beon Bid©|.S!• ia8©d a» a method of a©sa:tt^ifeg a^tyitloaftl stst© jutui yofalspemesto* A. lid^g© doe© .(20© to iO^O 09) is iiig©8t©& and til;© virine o©li©'0t©d to* the mxt §4 houre a&d analysed for oocorbio acid* This method, in it3 m^ny vsriGtions, io foimdetl wpm the principle ttat © l8i?ge p©»o©at«.g© of tii© t©8t do9# ia ©sei?0t@d if tfei© ti©,im©a OCCUPC ®IP© "^Atmrattedy* vhite almost m 9%$o If the tissues $i»e severely depletedo Sometimes, several daya ©l&fa© before tb© exoivatlpn responds. to repented teat doses (78). Herrie and Rsy (45) found th'>t low excretion and lack of reaponse to teat dose go parrlie1 with © history of loir pacerbic eeld intfike ,?,nd with n state of rscorbic acid subnutrition aa shown by cftpillery testa, but he recommendB the teat doa© method as bein^ a better method of measuring nutrition th«n the CBpillory resistance method beccuee it is more truly specific and more aoeur- 21 stely qu^ntlta' r.ve end beceuse Fepeated raeGeurernonte CBH be made ©t aoy ttme. Hr.rris and Abbasy (4?) found thPt the consumption of 25 ffig of secorbie ^cld daily will yield e, response to the test Son® generally on the first day and certainly 00 the second. Ordinerlly, the deterraination is m&de on the urine collected for the 24 hours following the teot dose, hut doae hsve suggested short collections (3 to % hours) with the argument that the peak of excretion eomos at about the fourth hour and drops rapidly for the rest of the tw©aty-foi**>. Hpigkt, Wing, ldli«ttfletd« fitnd MficLenethen (109) have found that 80 per cent of the excretion occurs in the first five hours. The test doses used in different studies have varied greetly, and there is a great difference of opinion £0 to the pereentege of excretion which indicates edequste and saturation levels of the vitamin in the tissueB. YouEens (113) estimated that Q.n excretion of 30 mg after i% 600 ag test dose shows that the subject is in "normal" vitemin C nutrition. Abbpsy, Herrla, end Hey (l) set a 40 to 50 rag excretion of a 700 mg test dose as normal. Fpulkner and faylor Oi) found that their "nonaal suhjeets*' (blood levels averaging i*T mg i>er 100 ml) ex^ creted SOI mg of a 1000 rag test dose in 2% hours. Van 22 Bo&elen (10^) 4©fia©d ^seta^&ttoa'1 as the p©imt «t v;>>lch a dose cf 250 to 40© m$ of fscorblc acid will result fa @, ^finite rise eb©v@. 30 asg edeoretl«ii» Wiplg&fc, lpvi»g, Xilll^Qfle^, ana teeliQ^fttfiiea. (109) 3pep©2»i ^hftt © tunnwil ©tfej^ot wxtt mme%® §00 lag of a i©0@ sg toufe a©s© lm 84 hcntra ©* 400 a»g in five hours, fov mnf jpeQuls'eiaest Q^eii©ei» "'s&fctay&^toa'" is e©tsis$^©s*e^ the point 9% %M®h %Q p©2» ®mt of & toot €©s@ trill h@ ®mv$tQ&' (97). $t@rvi©k ©»^ Sa^ck oonperod this i^thoa ©f d©t©i?* ulaiug 9o<|tt|v«80RtO' with a aetfeod in ^hl&k tbo iNibjoot is given £00 rag of aoeorbie aoid tstilsr fo» e, p&eliaitiBry ^QQtBPotioa B P«MP|O4*. ^© l©w©^t roopoa^o to -a toot 4oae after tfeio poriod is t©k©n, ©e th© mooaepo of ^estadPatloa" fo* tb©t aubject in. oubcecmect pofeiodo vh&tk th© cwb^ect is k©?pt on ^^Pioaa lovolo of inta&o to detemiae tl»© nittlama toQttireno&t to pm&m® * satiation* * For tbroe aubjooto., r©q:oiroia©nt$ &a det^rainoi bf tlto tv© mot^oio the mm®, tAillo in t«o> their ^or© oliaflhtly feifgiQ^ ro detenninsd by tho second netbod. WQV® In t®3$i> Faster and AM (t0) r©po?t@d t&at fch© amount of reduced eacorblc acid in the blood plasma closely follows the vitamin 0 tnt^se. Since tben, others hsv® ooftfirood tHio oox^©i©ti©n (ii5^i7*40)» Since the introduction of tlie plaotia aiero tltvatloa tootmiqne of 23 Parmer ami Abt# the plssmp- love! of ascorbic ecid has been uaed to s greet extent both In determining nutritional state end in calculatins requiremsnte. Some hair© tried to determine nutritional state by enslyaing the total ascorbic ©old content of the blood plssmc after reduction with hydrogen sulfide or carbon monoxide pnd find no correlEtion between totial fecorbic acid of the pi?.ana and the dietary regime. Farmor and Abt etatod ifis fflop© algaif to&at ■ %hm the t©v©l of t©ta"i eeteo^hio ©old ^3 a i8$$8Utti» @^ ®»tS'iti©uai etat©* ^laeaa'. l.©v©l.@ ©fid- Hid oaema^ o? feftftoiftlo «eid 9a:©s?et©d la the urine. ^a^iiKMtui''of &$■ vlt&jBitt ft eoBit^et'Of blo^t ami v»tm oa ©f, the-- g^nt «hi«h sh^w^d a atfss&i ■$@*9QN8& fee a t®^^ d©i© (^0- t0-S@-fflg-ef ■ * 706-818 *ss* deee)* ealy-ene hed a hleetf level of leeft than 0*65 asg pfc* 100 al# a level tihl^b; they efcdtte eo- IhAieatlh^ no^isai mtj!ti?iti©a..' -9heF helieveO that' the, ©nelow -level ■&&& fom© bee©- doe to at* aansualtf i®tf i^teSee ef vifcusltt 0 fey two p-^ocoding the te&i. OP tlhfee ia^e fhef stateH th&t. eeeaAlefiallst a bleed level may not bo IndieGtlsra ef the tatFltlomal status: btt% iM^Iievetf tl4«.fe t*& tim fflo#i& 5*»t# tfet© iietJi©d Wortii, ivletoMMEd^^ m& ¥@*i6it .(108) m©€© ©xl©^.siv©. ©OEipci'&tiv© stsdtee oa plcfimSj) 'ttPlEe, AQA BMA spin©! fluid €soaelL«€l®d that & ttotn&I (©♦? «8 pet 10® »^) -m& e wry. iiwri ©se^bi© ©©14. «©at©at; of bl©©«| plfefi^a (fe®t©!» 0«4 iag pep 100 ml) are almost invariably eseocietcd with eo^eapoaii^g ao^aal ©at eubnormsl valued foi? bofeti jBptaftl. f ittlA. euM ©eeotbt® aeid esvpojttcm ia f tv© IMMMW <af *«* & "tetMj (t®-©©'* ®ttdi ^b!&t> ttei^©f®^©'.p tii© fel©©$ pi^sisa.ia ,feii©'8© jp&sages fiai?aii8fe©8 ^a ^d[©!|S!imt© aiaS ©euuuat® ludos of '.vlt^wia 0 .matMit©***. Xtt- tlte »S«>g© #f '0*4 feo. 0*T ng |5©JP t00;asi| tlbsy "i^e^onsi©'!!^. filtfe'fe -ftSLl,.asftfti te@ jstc©^..^©*1' tb© ©lial©a^ evfttoatlMi ©f e©isi»vy* fl^owie* a»t l®^©t ,(99) f®^©^ %]fe©fe tlteVQ.^ftd..^. ^®f iBf ^5© 0©*l1P©1.©(f t®ll b©^©©!^ ,liFfll©,$>tf ^HH p'ltftglffiR .S.5t©03PbS.© ^©liS ©&, ttet®l?©.$ ©f 7S u^ ,&fid: .i©inS' bti%'is©% ® C5lgiiifi©j^ai» ©'©5?ip©l®^i©ja ©E. I©*'©!.© febov© ^Sfesfe. 1!li©$© ba©. b©©Xi ©^ai© ^!8©0ti©s #b©©t .ubitftlt. f3?s©t'i©ii ©f fcb© bli©©d $.$ tsb© b©©% iQ©#i!uifi: f©3? i@©'fc©i'aiii5iau ms^i* tloiial 8%ftt©* Its life© 'b©e& ©b©wa bf. 9tttl©9 m& B©t«di!iaiia .(18 ati.4 S4) tb®t 6f«o»bi^ 44Sd# 'wb©«i It is £i»*t .ab®©*»b©dt ©IJJI©©??-© lo: tb© fi|ife©iaft sad; fefeeii #i©virsi- 'i>©®©fc3P6t©© %b© 3i?©4 bl©@i ©©lie., ©JB A fev w©i»k©i!»©. {i44f76) bfef© ai?g«i©i tbat '©ito^©!© ■©? Hilt©!© bt©©€' t^iil. (giy© $ feot'i©?? ^i©i5^® ©f vHHOTia 0 ttat*ttl<Hi tbsm ©itb©^ vblfce ©©1ii*pl®t©l©t layer 8^ ©$> piaame. bedausd it does m©t fl^t^iat© a© t&© ottie&t «»*■•' BsatX©i? fe^a Ol^lMaati {i8); I»©ooai8iea4 wMte <seil* ptdtoiot tmfm fifialyeift slfee© th»y ift wqpoff&tiftit ivi^k e»6Ka@a» ^nay&ai Uili ($%} h&v© f©.ais€ that tibe &9e$*bi« mM t®m% ®t the wMt©' <s©il»piat©i®t lay©^ is tho lea* ZG beGomo aoploted la deficiency GDd the fii'Gt to 2'iee «iK>it aooMid aeii iittete- is r©:8Qffi©#* It is ©^iiemt tb&t motfots of tMa ispj^- ^©mli sla©^ tfe© p^©$#®©e of a lo&g ^ofttlsttdd fi^i?©^© dofieloisoy b©*t0» tkm m®%§ th® pisSffia .lo9ol< fh® latter, twwovd^* i# © bottom ©©©.cwi?© of ^te^ tfee diot IG# bees is tfed dsfs pteoofiiag tfe© t©8t. Ooldesl^ m& 'ttting^P (3$) .foand that vhaa ©#©©^hie aeid wag lugodted, tho plasma level ^^i© In @^@mt as howp, tfe©© pevgl&tod ®l? ^oe^hed a podle at' the esstd of tJip®© iiws m<& fell slightly ftt the e«fi of ©is hou^o. 2%®^ ^ec^iae^ed the detenaisentlon of the ttistfritlOB&l -Qtftte. hy ttsitas. ths fe©i#it €ssi gaa^^al hehftvio^ of .the blood owrao afto» sm vttol ^oo® of ii©^©^bie aoid. ffi&lttfttioa. of ^othodti>; foy..g&tegijiihi^ Kiitritifml $t&%® ilmOSi hm te@® aaii teat asd agaimot the' maiPload toothods of dete^isiftltig vd^ai»9iBeht& ohd mtPitlooal otftto* 1® 8e&B^«l# %&@ blood te$t8 have p^o^od; to he tho sioet ©mtiafaete^y ©md oofivealeat* • Stosa (.fl) ©tetee that the det8]Raittatio& of the vit&mift 0 ooatettt Of blood pUKnaa i# the oiiqpleet 26 dependable procedure{ he also states that the meet precise e,M dependable method of determining degree of saturation 1$ the rate of diseppeex&nce of an Injected dose from the blood etreara and that the method bated on rate of excretion of a test dose is less precise bat quite dependable. Van Eekelen (104) believes that the determination of fecorfcic ecid in plasms is better than urinary studies for determining nutritional state boccuoe it ie less compliceted end only one or two test® are required, while the urinery test oust be determined for a twenty-four hour output; he states thet that output is very variable for different people* Farmer and Abt (29) believe the blood tests to be more informative than the urinpry. Goldsmith and Ellinger (35) found in their experiments that there is e close correlation between urinary end blood findings &* indicative of normal or deficient viteain 0 nutrition, hat they believe that the urine tests mf he less reliable beceuce of the high pmount of interfering, non-Bocorbic ecid reducing sub* stences in the urine in such conditions as diabetes or when the subject is on e high protein diet* Some workerc heve found that the great variation in response to a test dose in the same end different individuals makes the test unreliable (**7,1©9#93)» Some of these have found (95,109) that instead of progressive increase0 87 in excretion with continued Mgh flosee ©f rscopbie acid, tfeeffe is a© furteher ti$@ f«* several, iii^©^ ©!► imtil %fe® deftes ©j?e diBContinuod for nevep&l w&&© te&H* ?fei* tt pl©t©att ©f ©3£@f»©fci©jR* H©iia©ffle«Ba ^©lievea uae da© t© « f©I'm ©f ifoeifi© dyfeeiaie mttoUj la «l&i©l> %&© ©*©@8S ©f vitfeisia dina^pefefe^ afteip *h® bQ&f ®$OVQ$ mpe filled. Johnson and Zilva (55) ataf.ed that, tit© povcent&.ge ©xc^ted i« feigfeoy ©» lover t©©t' d©8©« fctesu ©s high ©a©e 4i3id that the sunoti&ti retrirted is higher in the aecon(5 cose and i© a©% ladioetiv© ©f th© feru© »@«iBl*©ia0Bt» fli©a© ftte^tioiis 8!^©w .tli© tosewtaitity ©f ^a^eadlng ap©^ tli@; test S©B@ a© & tft©t|i©<& ©f (iet©i»iQiRi&g5 peqaipeiaent©, Pipcma Ijevela ^ij©*© i© a©ia© ©©ist!r©ir©»«sr ©*©«* *&&% ©©©©%it«t©e s «ioi?B»lw vala©© f©2» tfe© eccorbie g,©i«| content ©f blood. Ifeftgr •WMiHwiiowi h®v© ^©©fe ii?©¥a bgr trsrioae «©i!»k©.i?» feft©» ©tmai©» of plsfijafe i©^©l« ie j?©l©tioti t© ii©t;ax»y Greenberg, Rinehart, f5nd Phatek (4©) studied the fasting pleanip levels of 55 medicBl students,. Their values Mag».d ^Oia d#2i t© 1*4® m$ ©©©©i»M© ©©id p©^ 100 mi ©f blood; t&© fcvetfag© wa© 0*72 fflsg pet 100 ml. Forty-?Ive per cent of the students had ple.emB levelo below 0.72 mg. The experiraentere concluded thet velues below 0.72 mg were probably BUboptimel, that values between 0.7 and 0.9 appeared edequete, and that optimal 28 values were probably above this range. They ateted that vrluea below 0.5 mg per 100 ml must be considered Xm* Youmfens (113) found blood values of i.66 to '1.31 mg per 100 ml In eubjects on their usual or on e. forced intake. Twelve pstlento, who were suspected ©f having e l©t* Ifttftke, ha<i values ©f 0.8S lag ^© 1*09 mg p©i? 100 lal, the average being 0.539 mg. Van Eekelen (95) concluded from his studies that vain©© of f&m mw t© 0*4 ®$ aaeo&Mt ®>®M pm lOo at m® potop, £*m 0+4 t© 0*3 tag iai®d@i»at©iS 0*8 to 1*2 ag 'Vei»jr good,, aM .t&ow 1.2 as ©'S©©ll.©3at» l^iglit^ |iill©afl©M,. aa^l Iteeltsaatheft (109) fouM that the plasma values cf their aubjecto i/ho repcrt.od good to esseollstit iietas^f ^ijjt0j»l©fl WOP© 0.S4 t© 1*5^ mg jp©i? 100 ©ov, tliftt tiioa© ,»li©'«'0p©i,-t0j| f©©r to fmijp 4lotdipy tkiatorleO' Iwd :v^l«i©t of tt^a. 0*27 to 0.68 eg* Sou© ■©£ ttbelp. ^bj©©t$ wh© j»©i>o2»t©(ii $©©a dietaffir i&is* feorlea had, lovela- ©f .0'.3i ettt 0*37 m$> and ttio ta»lth dlete oon3iaere«i f&i? t© good had lev© 10 of 0.4l mg. Slesfii 01) ©©®©id©^@d 0*5 sjg ftftttttv^ift &©id |)©3? 100 ml to fe© tli©- 1©WF limit of noi^ml afed 0*8 to 1.00 og titet© ©vei?Bg© .seynol faetiiag vslii©^ Tfe© mm&g® mlm tp* Me «^4©©t8 vlHi tit© iBild©st #ao®a of sow^f 1ieo-.0*36 Mg and f©i? th© severe caeofl 0.2 jag. f®yl©x», Ofeaa©:, sad F&slka©!? (l©0) fosaad tfe© ^vefffeg© pXaoma level of 10 ecorbutic patleate t@ h® 0.245 wg$ the range waa .11 to .55 mg poi7 100 ail. There is some difference of opinion aiiout vhat value shove tisauo seturation. Kalli, Prledaan, s.n& Sherry (8l) atste tiiet 1.0 ©g per 100 ml o? over inaioete& eeturatioQ, vhilo Faulkner and Taylor (31} ctete that values over lA, end Goldsmith (33), values ei'er' 1.3 ag ludieate aacupetlon. Wont's, M©fe®a!m.fl etUSl' ^©^10 (108) ©©©d « valnd of 0.7 ag as t&a i©¥©0t tta&t ©f aoi?aai* igg AOOOPMO a0i4 psv 100' al 0©©3B®4 fe© inftitato goodt vltdmla 0 ttiit»ltioa« aM l»9d"t&ait. 0»5* « ©1M itet<a of dofl^ionoyv lf@ttwoil0p ooasiteFd valtaes b@i©^ d»55 ai§ pi^ ita ml plasma at fat^ologi^&l m$ ^a.l«es ^©low ©^^ sg ad .i0flBlt©» ly seo^butie. l© ^oga^da valuee of atomt 0.S ng ps? 100 at at zoofj. noTiual values i>Itliotef "^tottotlag Q^tu^atiwiii. fyoMmitk &M Mittm®$ (35) twaolnfisfl t^ftt ^a 03?igla&l i©v©l of 0.*? sig, Mffiebl^i 8 ^g OJ? a®2»© affe®^ & t$ot dose, iiiows ttofjalal -^it^fflls © tgtritlom* ■ Reg©Mles«; of the vl^s 41*^g©ao© of <§pi&io$a ■ ®w<®x vk&% eo^ttlt^t^s •eatewitlflik'* lev^lt ««• *tfe® iwoy limit of wtomtr*.It Q&BBB& to'b© goac^&llf a^o^ptod tfeat pl^maa ievsi© of 0.7 os* 0*8 tag asiMHPbt* &©i^ pei> 100 ml l&Aleate & fi^tl'Sf©oto3i,7 tett-tx»ltlo®al ©t&t©. 50 Requirements tn recent years, a great deal of work has been done on the determlnetion of requirements tor the protection of the orgenism from sourvy, for maintaining tissue saturation and for maintaining a "satiefectory" blood level* In the days when acurvy was still a great problem to mariners, it was found by medical men in the British Navy that one ounce of lemon juice per day was sufficient to protect a man from ecurvy. Kellie and 2ilve (5?) concluded from their experiments that 15 mg of ascorbic acid would protect from scurvy and maintain good health* Fifteen mg is approximately the amount of ascorbic acid found In one ounce of lemsn juice. Gfithlln found that 25 mg of pure ascorbic acid or the equivalent of that in orange juice was just sufficient to prevett lowered capillary resistance as shown by his positive pressure There appears to be a great difference between minimum requirements and values which are considered optimal* Pinoke and Landqulst 03) found that their four subjects required 1*1 mg, .7 to *3 mg, 1.1 rag, and 1.0 mg per kilo respectively to maintain a blood level of 0.8 mg per 100 ml of plasma* 51 Levcovltch ond Batcholder (65), doing excretion studies on three subjects, concluded that the minimum ©eeopfeie fecit vetyiipwuettt of fairly ©ctive colieg© cornea may lie at about 00 rag; with a §0 per cent margin of aefety, the recomraended Intake would be 75 mg daily. Helnemann (50), using the method described previously, found that one of his subjects expended 62.6 ag per dfiy foi* 37 day^j vhile another used 63*3 mg for 5> day$* He set 60 mg as the aetnal requirement for the adult male. By the seme method, van Eekolen (lO'l) fonnd hie "daily oxpenditar©*' to h© 3§ ag efffee* h© had been oa Ms ordinary diet and 63 mg tfhen he had a fairly large.'store of th® vitemin*. ffer&eh (Si) W ^^ *&m laothod-j ealoulated htts daily ©^penditttre a^ heing^ 56 ^© ©fcd that. of ao ©ight©en*'ye&r«©ld girl with so^rn^ fte 4-4 sag daily. Ralli, Priedraan, and Sherry (81) found that in their eubjocts, th® heat retention wa® usually maintained■on an infc&i© of i©t> w& 'daily*. Most of the ucr-k on requiremente had been done with the purpoBO of determining the m$0©0'&<5ry aeonnt of fiscorbic acid to produce tldeue 0sat«r».tion«tt A .ananary of th© rooults of SOB© of thoee otudiea uill he founa ih Table I. It is not yet known whether or not it io ad^isahle or of any value to keep the organls& in a at&to of -tiaeti© 3% aafciirafcioSb bnt fcto©*© Is A. gp^at; ^eal of evltenae tfe^t a©*© tluka. tit© lalatmim y^^ttiyeaoitfe t© protee-t fanrai se^vy is ©©'©©st®!?^ to fe^ep tit? otfgaiiisa in %%& best of feesitti*, 'Ml^sii tB^eospJdi^diiSiS 3P©^iai3?@Bi0si't'& it i® aoeede^ysr to #ti6t© whether those re<7,uicementc are siinimum OJ? «lefift©d ia tlM9' lt$kt of jMteea&t iGaotJlQig©. optimmi re It in- imteroitt* iig to note ttiat tfeo recoEEaoaded fiaily allG'waBC© fox*' 9lteaUi C. 'VA9 a©t et 75 ®i& $®% th© e&uit msa ssia 7© asfoj? tlie ©dialt ^oaaa by tfte Ootamitt®© OB fooao And- KiitPitioii of tfe© iatiooftt ItoiftAVOb CotfaeiX fa IStey-, i9^i* It xiiXX b© ao^od t^at tho^© f ignsr©© S^Q io©at©i bet^ooa the aftrepagfr ^epo^tef optinam ^©qiais'eae^tf and f&e ^^@p@gG O •< 0 13 «I $ O SO 9 -rip* % #4 o S3 o 43 o a 0 otk © C3 oo © P*» o 0 O t-4 Ox V0 •Hi 0 0) CO a ® © <J> +3 © d d © © 4» fit © © A« O *4 © o « © d« 00 o-o to ^ ©& ^e »© S o -P^ ©*» ^ © © ii O **! m 1 - Si ^ u *o ® i» 0^ 0 o o %4 *2 © © © — ® © I y> {<> 00 H * » * •» ft «•< 'CM <tt W © o ^ « «H tA © © tA O 0 E <u o Pi *n m ws m «A O lf> ©■ -© b* © «A ©1 t* CD .<H T4 *4 *1 in ♦ Je o © T4 # * © ou uo 0^ ©' «4 CM 4- ^ v© v© »' * » CO '** v* irt »^ mm 33 ^ ♦""N s® 5«3' 4J O A c M © JO 3* «*' o ^4 & o © S ** o &.** © •»" @M ft) •ri 0 & ® a «x. J^PM et r* t$ *<*» icS 0 : tk 4» 0 o o OS CD ♦a O m o <H <rt i?^ fo © P) H 0 tw H ® > © «^ o ^p ©<£> f ^H & 0 (M ■ **» '© # tk «J © rtlO © 1^ © & © ** : r-l© d © m** 09 ©t •H «rt m KN if\ co IA v© ^S O lA O O O ©\ V0 © IA Chi 4* ft* o o » ■• iH ♦ © 00 '^ <?•$ -Hfltf Vi. » ^f CM ^M <p*1 ^\ ^ ^ Ij^f' *«\ ' © SB G #<4 0Q -*> O © TO N h o1 ♦> © at a saOse (£3 Q 3** 35 Pactorc Affeeting Hequtrenottt Study of the phyalologioeil ftmoMono of psco^blc 6«id suggests that eertein factora may affect the requirements for the vitfciiiin by asm in varioua phaeea of health ond activity, Hie, requireiiieut for j eeorbie aoid 1$ greatly liie^eesed during prognency and lactation as would be expected, el nee tlie vitemln id' stored in fche fetus end placentG. *Biere ie evidence tlmt re^uirerueiit for aseorble acid beoPB no relation to ege,, height, or weight in the Mult (8i)> ft hea been founfi thet the ascorbic acid requirement if Falsei conaitlevably in certain febrile conditions such as tuberculosis, j'heumetoiu apondylitis, and pneuiaonio (82,41)* It has been suggested that the requirement is higher in other eases of heightened raetaboliam. Goldemith, Ogeerci, Bnd Gowe (36) were ©ble to maintain & plesme level of 1.0 mg per 100 ml in 10 of 12 subject8 with bronchial asthraa by the administration of 50 mg ascorbic ad id daily effcer a. preliminery saturation. Of the two eubjecte who were not able to meintBin e high plasma level, one was obese, and one wae taking thyroid. Koldaev ana Gelmnn (63) found that the ascorbic acid content of & guinea pig muscle was decre^eed after 36 the application of an Induction current whether the sniraela had received excessive, normal, or inadequate supplies of aecorbic acid. The reduction was somewh&t less in the musclee of ©niitiels which received lerge dooea Of the vitemin than in entmsls which suffered & deficiency. Todhunter and Robbine (.103) noticed seme evidence from their experlraentel work that fatigue pfter long hours of study and labor&tory work educed € levering of blood and urinary vitemin © content. Sxcrotion ctudies i& exercise C3tpos*imento heve, ao fpr, brought only conflicting report;» S&ffter (105) fitvtAlod the ftlgMAy Von Jezler and 'VHJQ&V *wt*%lwk ©f five perticipanta before ^nd after a ski race in which © height of 2%5© metere mift &OTiB©iafit©<i'i» © ©treteh of 50 Ian. The partiolpante Here given 30© mg Redoxon (s^tl^etlo ^soorbie mM) for seve© ikf* before the Jpsoe end for the six dpys following It. For each subject the exdretioii felt ©a the first or seoomd de^- After the e©»* test, the average nightly excretion for the five being 166 m& 156 log per 10© sil* for the iay preesiiag «DA the dey of the contest, end 115 ^nd 116 mg per 100 ml for the two d&ye followiAg it* This m&y be aignifleant, bat the drop mey have been $!ae to whfet leiaem^an refer© to ■&© n the specific dyn»inic 37 mtton of ©seo^bie aeid,11 in vhich the peak of exeretioia ie not w&tntp.UiQil oft,er r-epefitod high Gceec. Eeiiiel observed & definite drop in the excretion of his .eiihje^t© oa the fivvt tw i&ys foiloiJiag th©!^ pertielpatIon in & football game. Fa'trndt endi ^ehussele (i?) SB<3© exci-etlor, studioB ©.% $e^©:«i young aem «aib|eet© who' ¥@^©' ia g©oi pfeffei^ej. ti'ftiniDg. In flite of the subjeeoe, the reducing power of the %J»iEe • j?@©© m& ill t»o# it fell* affeer ®©vem!l fowfe of violetift ©&<B$®SB®} ^.fe© elmAge vas 1© th© aame dlveetioB f'©* eaoh ©abjaot in eaoh ease*. Th© exp©Fi* natttd>>d oomldl find no ©Sh©!? eacplsikft^loft^ fov tilift %h$.a that thoi1©-!© 6 4fo«iiQtit'tttiefi6l tfjpr^^ bt le&et ie «h&% ©o«4©ei*&s th© htii3@3?ohoi^a0'Bal 9ea.6ti9fMi in effort.B Sti©i»® IQ $oia9 e#id©!ie© that i& coBSiaow&hle ^aount of ascovoiv acixi may be lost in eneftt. Coi'nb'lost, Elcin, aad '^se© |S.©) jpo^^t^d th©t ffrpa 0«^$ to 0.64 isg of %h© vltonla is orxvetad with 100 ml of sweat. EGrnstGin (8) ffep0»t0(t tfeefc. fr^a? ©..5 to. 1*1 sag* p®y 10© si @f sweat tfas loat by Bsatu talne laborero. It was calculatsd on th© haei$'. of ^©ight to** fy'dB. evaporation that thos© laborers inlght hav© loot as much as 16 ng of ascorbic acia in an ©ight-howJ? $B& of trovle* On the Qthep heM, Wright and Mac Lens then (110) calculatod the ascorbic odd iMft ffom patients. In artifioial t&rew tpeatmeat to he about Q.O'U mg per 100 ml of sweat* Calculated on the 5i basis of & loss through evapornfclon of 1750 to 5500 ml in a five-hour period* the most that could be lost would b® two to three rag of ascorbic acid in that period* From this they concluded that vitamin G is mot lost in &nf ©pprecieble emount through exceesive perspiration* In the seme fever periods, the urinary excretion of the vitamin fill to a g^oater degree than could be accounted for by the loss in sweat. This drop they attributed to a probable loss through inoreased metabolism. There is also a conflict about the effect of increased dosage of ascorbic acid on physleal performance. Wlebel (106) noted better performance in scarcely any of H female athletic students in a ski tournament when large doses of sacorbic acid had been supplied* Basu and Ray (5), recording fatigue curves of the finger rauecle on the hand ergograph for four subjects before and after the administration of large doses of eecorbic ecid, reported that the onset of fatigue waa definitely delayed for some time after the administration of the vitamin* Crandon, Lund, and Dill reported that their subject could ran for only sixteen seconds before fatigue set in when he was in © state of complete deficiency* while after ten days* eecorbic acid therapy* the time was increased to 66 seconds. This may be compared to the 39 perfcrraBnce of men of the apme ft^e, which .^voragod 270 The (31.9sppeftrr.nce of blood lactate was follotred in tb© reeo^rex'jr pe^iofl fx»©® tli® ssaa fatiguo tests > and it was found that the lactate diseppe^red more slowly dtu'ing the recovery period wfton tli© auhjoet wa$ in th® eoorbatie 0t©tea ^Bho inlntite*.03cfg®& conewmption per kilogram of body weigfet* howevesp^. «&• a© hlgfeev in fclse fatiguo tosfe fefter th®rapy tbsa it was vtiea tb© sab joet fras ia the scorbutic state* 0r©ad©a, Lund, and Dili (2i) did »ot find ©a la* c^essod metabolism in ascorbic ecid deficiency, as some others have reported* Uteere was 6 slight dro^ in aeta* holism in the seorbntio state* fhis dr©3p>t tfeey believed use probably due to weight loss or infinltlon or both, fhey reported that, in the first #oar days of vitamin therapy, when the subject XWB becorains saturated with ascorbio ©old, the basal aetabolie rate was oonsistently lover one and a half to two hoars after injection than It was before the injection; following the period of saturation, the basal metabolic rate was ooadlatently higher tiro hoars after the administratloa of asoorbio add than it was before its injection. With all of the conflicting reports in the literature, it is obvloas that the mechanism of the aotion of escorblc ecld tn muacular activity and tissue reBpirption $9 not clearly understood* but there has been enough evidence presented to conclude that the vitamin does have some role in these metsbolic functions. H ■QMAfWR M tismm m MIS xrasfioAmon The question has been opened es to whether or not human requirements for ascorbic ftcld sre effected by muscular activity. The Issue haa boen suggeoted by the following factors: 1* Ascovbtc ftcld appsafs to fe&tf© e,a esee^tlsl rsle in the general mstabolic proeesBos cf the body* 3* Aeeo^ble aoid feppearfe t© Mve © ppoteetitf© or regulatory action on &t lea&t two respire torr ©nuyiaes i» «^©'l,©t©i nuscle. Foptfe©^ evlcience for its importance in tla&ue respiration i* shown bf the ve%m&6& <&.&$&+ ■ peerence of bloo€ lectete list the seorbatic 3» Bvl^ence feae been presented by esperlmentel work that the requirement for atcorbic acid IS Ffeised in conaitions aeoompsniefi by s.® . elevated metf boliem, as in fsvoap^ obeSttf, tliyt»j(>li therapy, ani ©xereise. It is the purpose of ttie fclioulng ©tJS<Sf to ^ete^ain© whether or not the hu^pn reGUirement of adults for escorbie &*id is ©ffeetei by $& leoresse ia physical aotitrity* 42 dHAPfBR SIX Genercl Procedure of Experiment Three subjects were carried through two experiinentel periods of nine dayo each. Throughout the periods, the subjects were kept on a diet of known low ascorbic ecid content, while a aupplement of the crystalline scid vao given. The basic diet consisted of cheese, boef, dried cooked prunee, end canned beets, csrrots, pears, potatoes, and etreporated milk. Foods taken ad libitum «©re egge* shredded wheat, Ry-Kriap, rice, flour, butter, nuts, sugar, coffee, tea, oeasoiaings, snd chocolate. The ascorbic acid contents of these foods will be found la Table II. The diet contributed 15 tag of asoorble ©old per dasr* In the first period of the experiment, the sotbjeets followed their regular routlee of a f&irty aedentery ttttddnt*8 life* lu the seeond period, the subjeets exercised vigoroualy for about one hour per day. For the first t^o days of the first experimental period, the subjects were given one pint Of orange juice, one glass at breakfast and one glass at lunch, in addition to the constant diet. This was to make certain that the plasma ascorbic acid levels were brought well above 43 Ascorbic Acid Content of Foods. Uaed In Experiment©! Diet Food ' Weight Canned beets Baet juice Cfnned Cerrots ean^ot' juice 100 s 10 100 10 100 feasp juice Prunea Prune juice SirapQfe&t$4 aailk Cheea© Beef Potctoec fotjalj /iSGcrblc Mid Content 3*6 .7 1.1 .2 1.2 $0 ♦2 80 10 60 60 10© 100 .2 *i .g .0 .0 7.6 19.1 ■W ^iiiint|l^i|Wil||)Bta^;y<B)irt^<Wi>>»i*Wl|Wiw>^^ Foods teken ad libitum were eggs, shredded whest, Rjr-Krisp, rice, flour,, butter, nuts, sugei% eoffee, tee,, seesonings, oncl chocolctio. 4* 0.8 mg per 100 ml, tile figure which Is UdUail7 taken as the %9irel of "good nutrition. * For the rest of the period* en ascorbic acid supplement of §0 mg daily wes given to AR, %M& women subject, end a aupplenent of 55 rag wae given to KD end LR, the two men subjects. This made a. total intake of 65 mg for the woman and 70 rag for the men. Plasma ascorbic acid levels were determined daily on each of the subjecte. Between the two periods, there was &a interval of four deye, in which the subjects had a fair ©mount of vigorous exercise and la which they kept their aecorbie acid levels reasonably high by teking about tiro oranges per day. In the nine-d°y period of exercise, the ascorbic acid intake was the same as In the first period* Plaema content of the vitamin was again determined daily. In deciding on the amount of ascorbic ©eld to be given to the subjects, it was Judged best to use the recommended dally allowance as releaeed by the Ccmnjlttee on Food and nutrition of the National Research Council in May 19^1* fhis figure was stated as 75 mg daily for men and 70 mg for women* A rough calculation of the basic diet preceding the experiment showed that it contained approximately 20 mg (about half of which was to come from canned potatoes)* To make up the recommertled allowance, then, supplements of 50 mg wore given to the 4§ vomen and 55 mg to the men. litter a more careful analy- sis of the constituents of the diet, in which the potatoee were analyzed as prepared for serving, showed that the basic diet contributed 15.l4 rag of ascorbic acid, 7.63 mg from the potatoes shd 7*51 froai the reat of th© diet. Actually, then, the total daily ascorbic acid intake was 65 isg for the woman end 70 mg for the men. These Intctcee are above one milligram per kilogremj the intake which Fittcke and I^ndquiat (53) found yould maintain, the plaeraa levels of thoir s^hjeote: at 0*8 mg-iier kg* Analysis of Pood a TTsed in Diet The foods used in the experiment®! diet were enfclyzed for ascorbic acid as follows: About 25 grans of the food were weighed, ground in a mortar with sand with a few etiMc centimeters of three per cent metaphosphoric aeM and oentrlfmged. the procesa was repeated twloe and the oaitpa^t €il^©d to 50' eo ^tth th© a@tapli©9ph©ri@ ■ ^ctd* Oae.&alf ©f the extraet was brought'to e- pH of .'33 to 3.6 #ith a olirate huffer. fo fonr ml of a soltttioa of 2,6 dichlorophenolindophenol (3 mg in 500 ml) In a colorimet©r tube were added 4 ml of the buffered extract. The tube was shaken and Inserted In the Evelyn photoelectric eclorimeter end the, .galvanometer reading recorded "fc 15 cecoeds and at 30 seconds (readings 0si and Gs2). The exceea dye was then completely reduced bf an added crystal of aecorbic acid and the reading egeia recorded 46 (Gr). A colorimeter tube conteining k ml dye solution with 4 ml of 3' per cent metaphospho^lc acid bufferoa to the eejne pH GS the extr&ct m& & cryctel of eacorblc ecid was pleeed in the colorimeter and the gelvenoiaoter adjusted to the reading Gr. With tbe inatrmaent set iti thla poaition, e, blank tube (4 ml of aye eoiution witji 4 ml of buffered | pet* cent aietftphoaphoric aeld) m& placed in t'he colorimeter and the readiiig recorded (Ob). fliie cor.centra^lo'ti of o.secrbie; aeld was ealetilateS aa^ordlig So 'ilie f'oilowiQg ©viustior-j 0 * K (log 0© * log ®t>) "She Itemt&Bfc tow %hl® Wv&tfU tm%%m®mt IB 0«€Q6* Pf'©i$©«lwe f©i»: 9»t6»ialtol*g ^i&ema A:se©3?felc A© 14 laval 8eve3?&l ii»0p# ©f ^looi (e&otifc *^ ae.)■_«*«»• eoltoeted in & tnalt pMml. ©eRfealmliag evyttftts of llti&m osa'tets©* ffe© . Qlcoti was ctir^ad with 0113 turn ^f t;*® broad eaC of a toothpick eat! the phisl stoppered and esmfS'lfiagad for three minutes. One-tenth of a aiillilitGr of fne clear plasma urn plp®tt©d off ssu^a tiUritt lato a IS ml ©oal@ml ■ eeia^lfage tube, 0*1 mt of ^eoeft^ty feollei aad ooolei m&%&t$.%lei®. m%®%> added nitli fcli© -•aae flpet^©^' JBa^ft.'^e ppo'|©lm p3?e®ipit@,t@& vltk 0.2 ml of § per ©©&% aaetap'ho®.'* pl»ori<3 e.oid. The taboa vere ahakexi to iaaure -aising ' titratioii could be ceiapletGd. The centrifuge tubes containing the daproteinized plRsma were removed from the rofrigorator and centrifuged for five ainutee. Two-tenthB of a mllllliter of the supernfitant fluid were placed In a depression of e porcelain epot-plate and 0.2 ml of 2.5 per cent motephosphoric acid solution in a neighboring dcp;?QS8lon. Hie dye wee run into the placma eolutlon from a microburette until there appeared a faint pint color which lasted tow fifteen aeconda. The metephosphoric acid blenk in the neighboring depression wae then titrated to a pink of aimllpr intensity. She concentration of eecorbic acid in the plasma was CBleulPted eccording to the following equation: ml dye x S x 2000, where 3 Is the strength of dye expressed in mg of ascorbic aeid equivalent to one ml of dye. Standardization of Dye The mathod of Standardising; the dye directly against sodium thioeulfate as suggested by Menaker and Geurrcnt (71) was adopted in preference to that In which the dye was standardised against eecorbic aeid, and the ascorbic aoid against iodine! the iodine being atandordised every four weeks with a sodium thlosulfate solution, which was standardised With the primery standard poteasium dlchromate. The new method out out several steps in the standardlfcatloh procedure and had the added advantage ot ueing th© sodium thiouulfato ctanderd, which 1G stable whoa it has oooe rccchod cqullibriuia, ratliQ? th^n thQ leas stable loditic solution. ' Txie thi'eo following aotliods o? stGriClGTclIsatlcn were comparod enti good checks TOCoivee: lite mothous just deseri'oea and the metlioa of QientiavdlztriQ dyo agaiaet an ascetic acid eolutioa which h&a been titratou witli & sfc&nd&rd po'c&osluiu iodate scluvion. i'ho procedure used fcr BtasidGi'dlaiag zho dye follows: 1G ae 25 oo 9is tile dye solution te$e pipetted into an Erlemaeyor t'icsk; O.f? gi^ms pota&iiam iodide cud 0.5 cc of dilvite culfurlc ccld (1:4) uere edded end the raixtu^e sliakon until all of the icdiiae was llborsted; .001 N. eediun thicsulfate WGC ?uii la from a 10 ml burette of small bore until the yellow Iodine color had practically diaoppeared; then 2 cc of 2 per cent starch solution were &ddet£ end the titration continued until the sclutioii bocrw© colorlesu. One ec of 0.001 1 iodine ia equivGlent to 1 til of OoOOi K scdiuci thiosulfate, end it has been ' ctown that i ml of 0.001 g iodine will recct with . tuccrbic acid, eo 1 ml of 0.001 1 ccdiura thloeulfcte ie egtttvalettt t©' ■0*088 mg of li«0'Oi»'bi# sola* f&efef©^©1, «b» etr-ongth of the dye eolution ccin be CfilculGted coecrding to the folto'&lng eQiiatiOE: at VtoJSLQ* 9 K % 81 "'•'■ '"*'<*■!■»'■■»-. .»■«--' 25 * mg ©soorblo aei^l equivalent to 1 ©e @ ie the normality of the thloaulfate solution. Stsndardizption of Sodium Thloaulfate The sodium thiosulf&te eolation was atanclardlsod egeinst 0.1 M potaselura dichromate about every five or fix deye until the fresh solution had become steblllsed. It wes found advisable to meke the thioeulfete solution several deye before l.ta first standerdiaetlon. The ccdlua thiooulfate atendai^dlzatlon was carried ©sat sLeeordisig to t%© ^r©®©tmr© eattltied by F^l©# m& Ee.Ba©y in ^^©atit&ttv® Mo*>$&&&® C^enist^y*w A t»8 B! p6l©,#&i«a' ioiSiio iS©l«itio'& (loist© tpm) tt^e p^dpajrodi 1® at' of t^ls- mae M&©<& t© a©i ai of wfcta», follow©^ by 5 Q! ©f; it ;-a. fey^^eliloti© mM* To t&ie w^t© adddd alotly. t?if& dos^taat c^fcwlng 05 sal «f at^nia^^ potaa^is ^aa allo^ot to: i3ta®i': out sl^atickfomte isoliitioa. of 6ia>e*t tti&tigut im tlM^e »iautea asa^ tBtom Allittd'd to ml and vi^ratcci wi'ik tko sodlam thi^salfat^ ■ solution■ SSld: no^aslity ■ of i&© thiosuljrato wOlaiiosi v;aj 3altbstlid folloiiiing ©tusitioat ';? 223 dOltttlttlUl —"'"^"ihukd;' " — .,.'.■,:••.•• •■ py&, . ?©©^t|r*®iibt ©g ^f tli©"<ay& -2,6 dioMe^o^euo* limdofij^aol i©i»©: • dissolVQi it* 9®® m% ot-httt wat^^.-^Mela fead b®©n-^ietill0ia f^om gl^so* • 'Ihe'aolutiott waa cooled m a&d 20 ml of phosphate buffer, pH 6.8 added* The solu- tion wes then filtered and stored tn a derk bottle la the refrigerator. The dye vat made fresh weekly. Metephofphor1c Acid Solution. The sticks of solid neid tJcv',3 rinsed several times with redistilled weter and dried to remove the coating of orthophosphoric acid which forme on the outside during storage. Five grams of the acid tier® dissolved %n a sssll amo»mt of boiled and cooled redistilled water and made wp to 100 mX in volume. Thia wee filtered dad stored la the refrigerator. The solution was made fresh about every seven days. Sodium Thlosulfate Solution. Approximately 24.82 g of crystalline sodium thlosulfate were dissolved la water and made up to one liter* This approximately 0*1 El solution was kept in stock aad a ©.001 K solution made from it immediately before etandardizat■on of the dye * Potassium Dlchromato Solution (0.1 U). Approximately ^*9 g of pure dry fotaeflium die&romate ^er© aceuretely weighed, dissolved la distilled ttater aai ©arefully sade up to one liter* Lon of Subjects feet KD, a graduate assistant in chemistry (23 years of age) was five feet, tea inches la Height aad weighed i40 pounds. He appeared to be rather nervous SI and complained of "indigestion" before the experiment fcogeut* Wt' v&s In dppctfpe^t good health otherwise. Att9# the expericent hz>& progressed, he f\nnoiincecl thet the Indlgesticn h&S discppesrea end thrt he he,d a great decl iaore vitelity then he hed had for $090 tine. , fhls state continued throtighoitt the entire ex^e^iaeht* Who© -Qeee- tiop.Gd cbout, hi© hafc!t$ of eatlag,, t% *a6 fouad thfet they «©»•© i^teguMr m& poov* hi© -uett^i hteeltffeftt helag e, oup of ©offee* fht© ©nhjeet Id th©. only one of the three fcho GjOnpl&ltteA of hel^g tlre^ iurlK^ the period of cKereiEe* Subject LE (26 yerre of cgc), the other rntitij felso © gvadw&te 6o#l$t&tit ih ohoaietr^, we© § feet* i© laches in heiiht m& weighed i%4 pounds. 1)9 nervcuo, and it WPG Ho, too* ^ppearea to disclceed th&t thare wee s one thing worrying hla &t the time of the experiments It we5 often very dlfflotilt to obtain blood semplea from him} thle may heve been beceuee of his unusuf1 nervous tension or because hla fingers were ocarred from burno. this subject eomplfeined of being tired on tho last flay of the ©atpori^ aent, but the oxerclee 414 not seem to tire him as it did ewbject KL. Snhjeet AR {19 years Of ^g©)^ the wlf© of $&+ w&s was 5 feet, J inohee in height aaA weighed 104 pounds fit the beginning of the experiment hut gained two end one-half pounds during the course of the experiment. She also appeared to be nervous end was very active, being aitoae* maker and student and working in a laboratory m^ of the time. The exercise never appeared to tire her. 53 CHAraR IV RESULTS jm DISCUSSION The delly plasma ascorbic acid levels for the three subjects in the two experimental periods are ehovm in tables 111, W90 mad V* the average of the last four days of each period was used as the level at which the plasma ascorbic acid content was maintained at that pertlcular intake. For subject AR, the average for the last four days of the control period was 0.72 mg ascorbic acid per 100 ml of plasma, and the corresponding average for the exercise period was 0.66 mg per 100 ml, the daily intake of ascorbic acid being the same in both periods. It iil%% be noted that the level dropped to 0.57 mg on the last day of the exercise period. The average of the last four days of the control period for subject LR was 0.60 and for the exercise period O.58 mg per 100 ml« The correepcnding figures for subject KD were O.78 mg per 100 ml for the first period and O.69 mg per 100 ml for the exercise period. For subject LR, there was no significant drop in the plasma level maintained in the second period. For subject Alt, the average for the exercise period was 0.06 mg lover than in the first period, and for subject KD the average for the exercise period wee 0.09 mg lover than the average for the control period. It 1& generally accepted that the titration method of mee.snrlnp eecorbic ecid let plasma is prectoo within ebout O.i tag per 106 ml. In view of this, it cannot be considered that the lower everagea for subjects AR and KD for the ejcercise period are significant. It is inter- esting to note, though, that subject KD, whose average level was 0.09 mg lower in the period of exercise, is the only one of the three who complained of being fatigued by the exercise. It ie worthy of note, also, that the trend of the plasma level in the exercise period was downward in the case of each subject. Considering the minimum "level of good nutrition" to be 0.7 to 0.8 mg ascorbic ecld per 300 ml of plasma, it ie apparent that & daily intake of 65 mg for the woman and 70 mg for the men (figures which are 5 mg below the recommendation of the National Research Council) were sufficient to maintain this blood level for subject KD in both periods and for subject AR in the control period and insufficient for subject LR and AR in the exercise period. Subject LR required more than 70 mg in both periods* As mentioned before, subject LR was worried &t the time of the experiment. It has been noted in this labora- tory end others that worry and nervous tension often 55 appear %o be accompenied toj a lo\i pleama ascorbic acid level. Thet may km® boon & footer in the case of the apparent high requirement of LR. It was revealed tbat SB Included very little exercise in his regular routine, while LH and AR were accustomed to a fair amount of vigorous exercise. It can be concluded from this investigation that the ascorbic acid requiremente for the three subjects used w©#e jtat vaiftftft M$t&$&l<Mia&tt tef &bm% &m km* of vig©i»oi$s ©xeyclc©; per #>?» IB .?ovl0vittg tli© Aitertture ©a tli© subject ©f exer- cise in connection with vitamin C requirementE, 1% is apparent that the experiments performed h&ve brought conflicting .tfewltftl. Mrnml <4i) ©ad ##m Jemtet ead Saffter (105) noted © drop la «s<i©*fei© ®0£d ©xofpetloa aft©* ©36©ffola©.,. while Sraadt ^ad. 8oluij»«0le (16) aoted m drop in the excretion of two and e rise la that of five subjects. $» poisibtilty ©f & lose of t^e witamla though sweet in exorcise should be considered. Calculating the feoufflar toss wltH tfee highest flgai»es fotiad l.a th© llteMH> tare, ©*5 to 1*1 lag, footed fef Besmstela ($)» It would ^ppeekF that the loss for the added hour of exercise for these subjects would not exceed 2 mg, an amount which could hardly be considered as raising the reauireiaent sigalflcsatiy. 56 AB mentioned previc-utly^ Koldaev and Gelmcn observed that there was a dcereeseti r*BcoPbie p,cid content of 6 guijica pig Eiuacle eftef the eppllcetlon of an induction current. It ie likely that %he etiwulus uoed resuXted in the ccatreictiou of a far' greater percentage of muscle fibora than would be used 1% any voluntary phycicel exercise, 00 thelz- experioient is not comparable with tills etuciy. It Is Quite poaeibl©, however, that If this €>3£P@#iradfit wo^e i-ovioatea ytUi iiibjocta wko uepo able and Hilling '^0' ^©vot© seveittl Jkotwi a. €©7 to- vigo^otis es©*** ciao, c a@fi&it© aror* iu plaftiaa Rsco^'Die aeM yould be notes* It is possible, aleo, thst a greater drop mey ti&Ve bson iioted tie.d the expo^imoiit beeri allowed to run fop © loiigor pe^Xou of time, SineG tha ti?eacl i'oi? the pleemG levelc of Gseorbic GCid ie (iQWirw&vd for each subject ±® ©;:erjeiec, it seems filvlB&ble ',0 stigiges^ ohe.t; the intake of GGeQi?bic acid be patdd* dtt^i^g Mrd pl^rttieal leteor ©r ©sereis©. S7 The ascorbic field requirements for the three euhjecto used were mot raleed significantly by about one hour of vigorous exerciee per day, but tile trend of tike plasma level of ©acorbic acid wae downward in the exercise period for esch subject. A isily IntskG ©f 65 mg ascorbic acid wa& enougVi to maliitaiii a level of 0.7 ag ascorbic 6eid per 100 ml for the woman subject in tit© control popioci and not quite eiiougri to uisiiitaiii thla level in exerciae. A daily intake of 70 mg of the vltamla was ewfflcient to maintain this level for ono of the men subjects in t'ae eoati'ol period and hardly eufficient fov the exorciee, perioii. An intake of 70 mg wa* in^nffiolent to maintain this level in the other man subject in aither period. 58 ***** in Bally Flasma Ascorbic Acid Values Subject AS ©ate Aieorbl* Add Intake Orange Orange 65 mg 65 mg 65 mg 65 mg (4 100 tee*) 65 mg i/ai 1/22 65 Big 65 lag 1/23 1/24 65 mg Average ©f 1/15 1/16 1/17 1/18 1/19 l/SO Juice Jtilee m • 56 aig/lOO ntt 1*22 1»I0 g pot©- •rr .71 *67 .72 last Orange Juice Orange Juice 65 aig 6$ fflg 2/1 65 mg 2/2 65 mg 65 8tg 2/3 65 lag 65 mg 2/5 Average of last fear days: t/n Exercise *92 *73 torn days: 1/28 1/29 1/^0 Miasma Level .72 1.04 .61 .64 .75 .68 .71 .68 Badminton Bicycling Bicycling Bicy&ltsig Bicycling Bicycling Banning 1 Bicycling 50 mln. one hour one hour one &onr one hour one hoar 1/2 miles one hour .57 .66 aaffir^'j.r/r'rr/aa'jjtfjaisaaf.- Table IV Daily Plasma Ascorbic Acid Values Subject LR mtwmi+mi ttmmii mhimw*mm*+i*i**t*^mHmtm*m* VMMfMMtM*MMHm(«4MWtoi Aseo^ble ■*.•. Acid Intake Bat© Plasma lievel Exerciee mm+wmmm+**mv*mm*'i**m*m****+<*&im»ii**~+*™ 1/1$ 1/16 1/17 1/1% 1/19 1/20 1/21 i/n 1/23 ©paeg© juice Oraag© jute© 70 mg 0 mg ■I+ 100 g pota- 70 IBg 70 jag _„ of last four dtye: Orange juice 1/28 1/29 1/30 7@ mg 7® mg 2/1 2/2 70 mg 70 rag 70 mg 2/4 70 mg a/5 Average of last *+mm+*mi<i*+mi*m*m • 71 -67 .68 • 57 • 53 .61 70 mg 7® fflg f©u# days1 .48 mg/iO0 ce »93 1.04 .60 .71 1.07 .60 .54 ...56 .35 .65 .57 On© hour handball One hour handball One hour handball One hour handball Running 40 rain. Running 40 min On© hour handball On© hour handball .58 mmfm^<m'i*t'tmmuimi<ti^>^mt i'itiii<iiMwiiiwi'w 60 Table V Itelty Piseraa Ascorbic Ael6 Vfeltt©© Subject KD Bat© Accorbie Pc'M Infceke Pi&mae lievel 1/15 1/16 1/17 1/18 1/19 1/20 Ore-tig© |ii©© O^&ftg© Juice 70 ajg 70 ©g 70 rag »ST ag/lOO ©^ .86 1.15 7© m Bserdlee .Si ,78 (■*' 100 gf potato©©) ,78 1/21 70 mg 7© ag .32 1/22 7© mg 1/23 .72 1/24 ♦ 78 70 18g &vmm& of tmt torn toys:. .78 1*16 1/28 O}?©©g0 Jiiic© Otetxg© Inle* 1/29 i*a5 70 rag ,72 1/30 1/51 .58 7© m 2/1 7® m 2/2 70 ajg .72 2/3 .71 7o m 70 ia§ .68 *A 70 usg 2/5 .65 A?©s»ag@ isf last *69 Ola© how* feunab&ll One hour handball 0»& feou* fesudbsll Oae boQ» teiKifeall EOBalag 40 islu* fiottBlog 40 mtm* me ii©ui» ImnAtoXl One hour hendbdl BIBLIOGRAPHY 1. Abbeey, M.A., Hfirrle, %*$*, Ray, S.K., and Merrack, J.H. Diagnosis of vitamin C aubnutrition by urine ©ta^ly*!*. |»&no©t, gtl399~l405,. 193§* 2. Abt, A.F., end Fermer, C.J. Cevitamic ccid content of the blood plesme. Amer. 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Harris, L.J , and Abbaey, M.A. A simplified procedure for the vitaJBia 0 mtm teat* Iiahoat 233»l429» 19?7. 44. Harris, L.J., Mapaon, L.W., and Wang, Y.L. A simple potentiometrio method for determining ascorbic acid, suitable for use with coloured extracts. Biochem. tfou*. 36t183-195» 1942* 45. Harris, L.J*, snd Ray, S.N. Diagnosis of vitamin C subnutrition by urine analysis. Lancet 228:71-77, 46. Harris, L.J., Ray, S.K., and Ward, Alfred. She excretion of vltamla C in human urine and its dependence on the dietary l&teke* Biochem. Jour, 275 tOil-SOii, 1933* 47. fart Bell, tf**r*M. # and $rvia, J.|»* Flasoa vltamla 0 and serum protein levels in wound disruption. Jour. Amer. Med. Assae. 116?669*674, 1941* vltealn C metabolieia of four pr'e*tJChool children. *rotir. Bi&tHtioa dit$09*514• 19^1. 3aiO' ©iteiteticm ©f Vit6mla,e .is aoraai individual' f ©lloniag.' '0 Mtt|Mi«96^t# -Qtia&tltetitfe aaiDlaiets»6ti©a tA the f.©ria''of ©Mag© $kittot .itw&Zml®. aoid by mouth, tad oovltemic sold Intravenously. Jour. ■HttWmpft 11*135*1*S #.1936-* 50. Holneunna, Martin. Hum^a requlremonto tm vlt&nln 0* Btoefcora. Joa?* 30ja299»S506> 1936* 51. Heinemann, Martin. Requirements for vitamin 0 la iaaa* -Jefi^« Clla.. Ia^©8t... I7i 671-676 f 1933* 32. H0ia#3&aaa, MUrtla, 4ad H&aid*. F*^» Fa©t©i»# tftftt influence the peesage of Docorbic a©id from serum to cells la human blood. Jour. Clin. Invest. 191*69**73* lp*0* 53. Hess, A.P. Smvvfi pmt and present. j«&* liippiaoatt: c©a®>.®ay, 1920. 54. Philadelphia, A.F. * aad ©©a^amia;, H.S* tJ^iaa*? ©x63?©tioa ©f vitamin C. Proc. Soc. Exp. Biol. ©ad Med. 31:855- IQ-S©,, 55. Jclmaon, S.W., and Zilve*, S.S. The urinary excretion ©f ©ecorbic acid and dehydroaacorbic acids in man. Biochoiai* Jmv. 38; 1393*1*08 # if3** 56. ifellie* A«V*» aad Sllta^ S«9» SSi©' 4©ti©a ©f !• a*06Pbia< a^id ©a tie ia yitye i»es|>ii?atl©a ©f liv©^ tissue from guinea pigs on a restricted diet. Bio* stei. Joaf* 35 < 783*765, 19^1, • 57. Xellie, A.E., and Zilva, S.S. The vitamin 0 requirements ©f aaa* Bieeheau Jow* 33iiS3-l6*, 1939* 58.. Slag* ©*0. vitdmlft €'■. 19*1. duMleai :a©t|i©d» f©* ■ d©;%©rmiaati©a of lad*- lag# ■eheai.; Aaal« .M» 13id$5*627# • 59.* Blftg*. ©»0« ffe©. ^©aiet^f of vit&nia 0* fha Vitamiae. Gfel©,&g«?i, Aawrtasgi SadKial lA8s©©latl©aj 1939*. 60* King, C.G. The physiology of vitamin C. The Vita* mina. Chicago, American Medical AssociatioQ, 1939* 61,. Ki&e* f ♦#* ■ ?it©iaia CL es:$©^fei©' fieid* E©#'©* lot838*868* 19$6tf -68* Kiiag. €*©*v nad il*&t6&* l$»lt« fhf«jl©l» ^@ iftfXtt©^©© ©f HtQ* 6?. ftoMaev* BM*, ■&&&$&.%&&&■? 1*11* f!a© effeftt of etreauoua work oti the ftscorbic ecid content and the ei-.Idf'.ti.on-re^ucticK procesnee In the muaoles at various ^esreos of vltamla 0 scturatioa of the> ■ ©^g^mim* maia* $imk<m* ■mm>- iit^iis 1959* XHttv&tKHR Alwtws^i* mi 8ew» -9^37.» 1919* A €©fe©t tn ita© ia©t^te©li&3aa ©f oapenatle ^eids la. pttematove iaf0»tar flh© IP©!© ©f vltanla 0* Selea©© 9Ot680*681^ 1939*' 6$. I»©v©<wl^, SteftiAtta^ <mfi BetQlieM©^, 8*ti« A&©©j»bl© mt<i Gmmtim. &t 'taMWtt l©v©t«j ©f istMlE© ^s yei&ted to capillary roEistance, dietary estimates, ©nd human ^©tul^eaGftfe©* *r©tar* W«fc*lti©ft. t^*399*^0Tp 19^2,' 66, Loanos?, E.L. Studios ©m heaoglobia regeneration in ^etiealt wit^ vitcaoitt 0 dafieie&ftsr* ^©u^* 01in» li3V©«tj* 19JTB7» i9*0* oeitipv^* ^©ur. ABI©»* Met* .Aadoe* 11OI66>»6O8« i9^i« 68* fittMrsliji f&aaik* AmtOfWM 8*14 && a ^r©©ai?s©F of 99191m ©©a^;l©ai©ut* Batar© i3TJ-6l8-6i9.j 1936* 69. I3@t©v©^8^ f«, Oanaoft* f.F*-> &a$ Wlgfeit.,. 2»8* Wtsmla 0 $©fi©i©®©y**©J!fcl©al ami ttioi^^peutil© pvabloas* »@r* 3*m* :W©d* sal* .19Tl34©*?31* 1939* ?4* W&M&mf, l*ir#> aad .SfeeppaM, «* $&f0l©t©gl©al ^vopovttaa ©f asaavbla ■ »al4» j©u^.- Suttiti©® IT* 99oa« M* 1939* 71* Hfdtta?ia»» LI*,. ttibA-(hn9*a&%* I*i* SiMMte^dHtfttlaa ©f 2>6-DichlorophenclindopJienol--an imppoveci method* Ind. Bag. Ghem., Anal* Ed. 10:25-26, 1938. 72* 'StiMli®, l*.Si*,, a84 Sttt3<a»-f A^» $he d©t©s?ffllaatl©B of ascorbic ecId in pleeme. Jour. Blot* lt»t:673'-606, 1937; 73. Mirsky, Arthur, Swadeah, S., end Soskin, S. Total ascorbic eoid content of htunan blood. Proc. Soc. mp. MUX* m&* 32^150-1151* l$li. 74. Mitchell, B.S.« MerriEm, A., end Batchelder, E.Ii. The vitamin C etetua of college women as determined by urinary excretion. Jour. 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Further analysis of the role of aecorbic aeld In phenylalenlne and tyroelne met^bollem. Jour. Biol. mm* i40ti3>l6©* 19*1* 89» Mfe'look.^ M.M., s^d SllMiPSteim,- BGMfts^* $1® ooati?©! cf expsriaerjtal c.leapto^i^rie, by msaris of vltemiR C. Science 90:517* 19J59* 90* 89AlMls» E'#S*, aad Slib©j?©t©i8a, S*B* ■ fto ©xoretioo of hoffiogeatielo sold ar^ ot^ar tyroslti© metabolitee by the vitfiiila C - deficient gunlnoti pig. J©ar. Slol. Chem. i551451*^58^ 1940* 91. fife&v* i*B.,, «s^ fljelafedo*,' 1.1:* .ImpoftSBe© of th® e©i3tsltl2ati©B jnaetefelcm. 1®. th© cllaic©! pfe©Eioinemon of allergy, toer. Jour. Diaeasee Children 58: 581-585, 1939. 93. fltoespasg*- K&rgarot, ami :sS©HeJ»s?f, ^*¥* ^©' fliyalolo* gicel properties of ascorbic ecld. Effects upon water balance end upon body composition of guinea ■ plgt« iioofee®* Jour. 33*6§§-6'|7j. 1939-* 93. Slgal, A., and King, C.G. The influence of vitamin 0 deficiency upon the resistance of £ulne6 pigs to fitpMfeevla toxtB* ifw*. fimmm©!* l^pef* fh©i?a» 6itl«9-j 1937. . 9^. Sloan, A* A comparison of methods for detecting and ^reding oubclinicsl ocurvy, 2OUT. Lpb. Clin Med. $5tiei£*l686j 193S.* 95. Smith, S.L. Human requlromejits of vltamic, G. The Vitemifie. Chicago, rv^i'iao.n Medical Aecociftlon, 1939. 96* Snov, G.A., eud Zllva, S.S. The actiosi of l-f.acorblc aeld-oii tbe la' yttyer - yefpjLgfefeloa of liver tiesue fs»©m galnea, f5fa-©ii 6 j?©Bti»l©t©d diet* Bloafeeau iom*- M»787*8@0v .19*1. 97* StdpiwiWj, D:^,, ^Bb& i&wl©^, 1..1.. ftid1 pfefttttoa of roduood ascorbic r.cld In biood. Jou* . Blol C^m. 11SJI653*6$8, 1^36.. 9@* Ufeetiapt, ■ip.P*,- ami'lieSfia0»tli| J.S. ImtFev^aottda-eeoylsie 461d .!» eaiipe&ittettfttil ae-ttt© ^emo3?rlifeg©9. I^noelt slOtSiS-SgO, 19^1* 99* Sto^vi^fep- 0*^*- emd HswiGk, a^.H* Bff^ot of conti-olled AJMoi&ift <&«W iigeiDtioa uforn wiiwwy exe.rotloti and plasma conceptaction of ascorbic ecid in normal 10®. fteylWj F^H..!**,, ^fea-805, t9S»2»©tt«e> 6ad fottllt!tt9*,,^*Bl» Estijnatloti of reduced ascorbic &cld In blood serum and pleema. Blochem. Jour. 50:ili9-ll?5, 1936* 101* 9&ffal» Sbuc,. MWI Sa^vofp 3*0* SffdOt of ab»©l»!;@ alia fart 1^1 ?ii6ni& © <30fiol©ia©3r ©m ij®'®l.i8g. of ^©tt-ade. fro©.. Bo®* Sacp* Bl^l* »©<!. 38i5l8»$25. 1933* 102 ^ f©^miLta*,;, l.U* ffe© uetr©:s» KnovSddgo of vit&mlR. G. la Hoaltji end dlnsoato. -iToiil?. itei©.i»;* Mofcat* MeoO'* 16 Jl**!!, 19%0. iOj* fo#seBfco*,., S*®*.-, ae^ Botefelu** Ruffe 0* ®l>e©!»vmtt0n® on fclie emotmt of aeco^bic acid requipesl to mr>int;ain tisaue soturatlon tm ikMBttftl ®.«lal:ts. Je«9P« Btotvitlott 19tSo>»t70j, 1919* ■ 104. i©kol©»^ iifeiPi©* 0'ii tlio. anottttfe of eeeo^blo aol^ in 'blooa. ©»i vuMnift* jh*. daily itows» peQttlvemeiitd foj?' a«e®j!»feie sola*. . ll6olt©-®« #®aip.- 3@'t@g9l-22989 1936* lOfU ^011 tjreaie^, A*,*. andl-Bftfftoip^ <?* Vli^ffitix t—Bddei'f :b&l dlttatAllge* Sf©i»t,li0:h©r .JteiMH^Ieri^tdiig. freltteer mi, WoolionBeiiF. S9*'332*333, 1939*106* Wi©^©l, S* fat5©»0ii^i«»ng©^ ib©r Vitfesln CJ^^BeiaeittHgea feel SftMrtattttenfeltHMUNu Ii0ftt» H&Afr lf««lum0dkr« 6S8 6<l, 1939'* TMI 107. Wclbech, SB. The pathologictl chTr.ges resultiBg from viten>in C a.aficlency. Jour. Amer. Med. Assoc. 108$7*15, 1$37* 108. Wortis, Hermpn, Llebeman, J., and Wortis, Ethel. Vitsaalii 0 In the -bidoii. spinal fluM,, m& ttvlfie« ^««r.. Aa^r* Sf©^* Asawu li^*l@96-i89t, 193S* . Wright, I.S., Lilienfield, A., and MacLenathen, taMk* tn^tmt Hei*' 60<264*27t» 1957. 110. Wright, 1,0., c,r>c? Me c Lena then,, EliEPbeth. Excretion ®£ vitamin' # 16 'fciio awafe* Jow*- tftb* 0lte/ fteft* g%8S©^*i©S.J> lf3f♦ 111- Tft^oMlESr'* l#»tlfe, ASaMute^ ,P>, «ft6 Klmg, 0*Q# file vitrmln 0 consent of hurapin t58aues. Jour Mol. 112 ♦ ^ItoyfilB^,, S» ©s tftj» l&ftiaea<5e of vitemin C ©a AAft&liylaetle shock. Eltfea&ftt©' A^oh* txp* l©a»» ift 17-37* 19*6. StetPltlmfc Afeet^sot© e,m S©vg# If :96fl I9%d* 115. Youaiana, J.B. The present etatua of vitamin defic?.encio8 in nrftctlce. Jour, Amer. Med. Aeeoc. 1081 i5*S0, 195T.