Charles Edmund Simon.

A Text-book of physiological chemistry for students of medicine and physicians online

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A TEXT-BOOK



OP



Physiological Chemistry



FOR



STUDENTS OF MEDICINE AND PHYSICIANS.



BY



CHARLES E. SIMON, B.A.,M.D.,

PBOrESBOR OF Cl^ICAL PATHOLOGY AT THE BALliyOAEllKDICAL COLLEGK.

THIRb*'gjyTTIOK THOROrj(^TiLY* REVISED.




LEA BROTHERS & CO.,
PHILADELPHIA AND NEW YORK.



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PUBLIC LIBIIARY



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WILLIAM J. DORNAN. PHILAOA



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PREFACE TO THE THIRD EDITION.



In preparing the third edition of the Physiological Chemistry
the writer has attempted to bring the volume up to date without
increasing its size. This has been somewhat difficult in view
of the large amount of literature which bad to be considered. It
has been accomplished, however, by eliminating all unnecessary
theoretical discussions and by presenting only such fundamental
facts as seemed essential to a proper understanding of the sub-
ject matter. The aim of the writer has been, as heretofore,
to present a text-book for the use of medical students and phy-
sicians who wish to keep abreast of one of the most important
branches of modern medicine, and also a guide to practical work
in the laboratory.

Charles E. Simon.

1302 Madison Avenuk, Baltimork, Md.,
1907.



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PREFACE TO THE FIRST EDITION.



In preparing the present volume on Physiological Chemistry I
have endeavored to adapt the book as much as possible to the wants
of the medical student, and the physician who in the past has been
unable to devote the attention to the subject which it merits. The
work is intended as a text-book for the lecture-room and as a guide
in the physiological-chemical laboratory. Theoretical discussions
have been avoided as far as possible, and it has been my aim to
present ascertained facts as concisely as appeared consistent with the
importance of the problems under consideration. The various
chemical methods have been described with all due regard to
necessary detail, but with the supposition that the student's course
in physiological chemistry has been preceded by a course in general
chemistry, such as is offered now in the majority of our medical
colleges.

The subject-matter has been arranged in such a manner that in
the first section of the work a general survey is given of the origin
and the chemical nature of the three great classes of food-stuffs, and
also of the most important products of their decomposition ; the
second section deals essentially with the processes of digestion, re-
sorption, and excretion; while the third portion of the work is
devoted to the chemical study of the elementary tissues and the
various organs of the animal body, the specific products of their
activity and their relation to physiological function. This arrange-
ment has suggested itself to me as the most satisfactory for purposes
of teaching.

References to literature have been omitted, as they did not appear
to be necessary in a work which is intended primarily for the
student. The names of the grand-masters of physiological chem-



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vi PREFACE.

istry and physiology, however, have been introduced into the text
as a matter of historical interest.

To my friend, Mr. Charles Glaser, of Baltimore, I wish to
express my sincere thanks for many valuable suggestions and aid
in the revision of the manuscript. To Messrs. Lea Bros. & Co.
I am indebted for many acts of courtesy.

1302 Madison Avenue,
fiALTHcoBEy Mb., 190L



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CONTENTS.



CHAPTER I.
INTBODUCTION.

PAGB

General chemical composition of living matter 17

Forces at work in the living world 17

Character of chemical changes 18

Synthetic processes in plants 18

Oxidations and hydrations in the animal body 19

Chlorophyl 20

The food-stuflfe of the plant 22

Synthesis of the carbohydrates 23

Glucosides 24

Mannides '. 25

Synthesis of the fats 26

Synthesis of the albumins 26

CHAPTER II.

THE ALBUMINa

Elementary composition 27

Reaction 27

Solubility 28

Crystallization 28

Diffusion 29

Behavior toward polarized light 29

Coagalation . 30

Denaturization 31

Behavior toward neutral salts 31

Behavior toward alcohol 34

Special reactions of the albumins 34

Precipitation 34

Color reactions 36

Structural composition 38

Molecular size 46

Classification 46

The Native Albumins 47

The albumins 47

The globulins 47

The glnco4ilbuminB 48

The keratins 50

The histons 51

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viii CONTENTS.

TAQE

The protamins 52

The nucleo-albumins 63

The proteids 55

The nucleoproteids 55

The nucleins 66

The hemoglobins 57

Thk Albuminoids 57

The Derived Albumins 59

Fibrin 59

The coagulated albomins 59

The albuminates 59

The albumoees 59

The peptones 61

The protones 62

CHAPTER III.

THE CABBOHYDBATES.

The Monosaccharides 64

The Hexoses 64

Glucose 67

LffiTulose 67

Galactose 67

The Pentoses 68

The Disaccharides 68

Cane^ugar 69

Maltose 70

Tsomaltose 70

Lactose 70

The Polysaccharides 70

Starch 70

Inulin and lichenin 72

Glycogen 72

Dextrins ^72

Celluloses 72



CHAPTER IV.

THE FATS.

The Fats 74

The Lecithins 76

The Cholesterins 78

CHAPTER V.

THE CLEAVAGE PBODUCTS OF THE ALBUMINS.

The Mono-amino Acids . 80

The Diamino Acids 87

The Organic, Non-nitrogenous Derivatives 90



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CONTENTS. IX

PAGE

The Nucleinic Acids 94

The pyrimidin derivatives 98

The purin derivatives 100

The Ureids 104

The Kbeatins 107

The Ptomains 108



CHAPTER VI.

THE FERMENTS.

Oeneral properties ' . 112

Chemical composition and general reactions 115

Mode of action 116

Classification 116

The proteolytic ferments 117

The amylolytic ferments .... 117

The inverting ferments 117

The lipolytic ferments 117

The ureases 117

Ferments which transform amino-acids into amides 117

The histozyme of Schmiedeberg 118

Ferments which cause the cleavage of glucosides 118

The nucleases 118

Ferments which split off carbon dioxide 118

The oxidation ferments 118

The coagulating ferments 119

Beducing ferments 119

The kinases 119



CHAPTER VII.

THE DIGESTIVE FLUIDS.

The Saliva ; 120

General characteristics 120

Amount 120

Chemical composition 121

Ptyalin 122

Mucin 124

Sulphocyanides 125

Nitrites 125

Extractives 126

Mineral constituents 126

Gases 126

The Gastric Juice 126

General considerations 126

Amount 126

Chemical composition 127

Acidity of the gastric juice 127



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X CONTENTS,

PAGE

Determination of the total acidity of the gastric contents 128

Hydrochloric acid 129

Origin 129

Significance 130

Tests for hydrochloric acid 130

Estimation 131

Lactic add 133

Tests 133

Estimation 133

Acetic acid and butyric acid 134

Tests. 134

Estimation 134

The ferments of the gastric juice and their pro-enzymes 135

Veimn 137

Isolation 140

Estimation 140

Pepsinogen 141

Tests 141

Estimation 141

Chymosin and chymosinogen 141

Tests 143

Isolation 143

Estimation 143

Other constituents of the gastric juice 144

Gases 144

The Pancreatic Juice . 144

General properties 146

Amount 146

Specific gravity 147

Chemical composition 147

The ferments and their zymogens 147

Trypsin 149

Test 150

Isolation 150

The amylolytic ferment 151

Steapsin 151

Maltase 152

Chymosin 152

The Secretion OF THE Glands OF Brunnbr 152

Tjie Enteric Juice 152

Enterokinase . . 1^

Erepsin • • 1^

Secretin and prosecretin 155

The Bile 1^

Secretion 156

Amount 157

General properties 157

. Chemical composition 158



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CONTENTS. xi

PAGE

The mucinous body of the bile lo9

The biliary acida 159

Isolation 160

Tests 161

Pettenkofer's test 16»2

Physiological lest 162

Gljoocholic acid 162

Hyoglycocholic acid 163

Taurocholic acid 163

Hyotaurocholic acid 164

Chenotaurocholic acid 164

Cholalic acid 165

Hyocholalic acid and chenocholalic acid 167

Choleicacid 167

Fellicacid 167

Lithofellic acid 167

Taurin 168

Isolation 169

Glycocoll 169

The bile-pigments 170

Bilirabin 170

Teste 173

Isolation 174

Biliverdin 174

Isolation 175

Biliprasin 175

Bilifusdn 175

Bilicyanin 175

Bilipurpurin 176

Choletelin 176

Bilihuroiu 176

Cholesterin 176

Teste 177

Other organic constituente of the bile 178

Tbe biliary iron 178

CHAPTER VIII.

THE PROCESSES OF DIGESTION AND RESORPTION.

The DioEfiTioN AND Rbborption OF THE Carbohydrates 179

The Digestion of the Albumins 181

Digestion of the native albumins 181

Gastric digestion 181

Tryptic digestion 185

Digestion of the proteids 187

Digestion of the albuminoids 188

Rbbobftton of the Products of Proteolytic Diqestion 189

Erepsin 189

The Digestion and Resorption of the Fats 192

Autolysis 193



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XU CONTENTS.

CHAPTER IX.
ANALYSIS OF THE PRODUCTS OF ALBUMINOUS DIGESTION.

PAGE

The Products of Peptic Digestion 195

The Products of Tryptic Digestion • • 196

Keactions of the individual albumoees 197

Hetero-albumoee 197

Proto-albumofie 197

Gluco-Albumose 200

Deutero-fraction A 200

Deutero-fraction B 200

Deutero-fraction C 201

The End-products of Albuminous DioEgrriON 201

Antipeptone fraction 201

The mono-amido-acids 202

Leudn 202

Tyrosin 203

Aspartic acid 205

Glutaminic acid 206

Glycocoll 207

Tryptophan 208

CHAPTER X.

BACTERIAL ACTION IN THE INTESTINAL TRACT.

Indol 213

Skatol 214

Phenol 215

Ptomains 216

Bacterial Decomposition op the Fats 216

Bacterial Decomposition of the Biliary Constituents 217

CHAPTER XI.

THE FECES.

Consistence and fonn 219

Amount 219

Odor 219

Color 219

Macroecopical constituents 220

Microscopical constituents 220

Reactions 220

General chemical composition 220

Analysis of the Products of Albuminous Putrefaction 221

Hydrobilirubin 222

Excretin 223

Stercorin 223

Meconium 223



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CONTENDS, xni

CHAPTER Xn.
THE URINE.

PAOK

General Characteristics 224

General appearance 224

Color 225

Odor 220

Amoant 220

Specific gravity 227

Beaction 227

Determination of the acidity of the urine 229

Chemical composition 230

The Inorganic Constituents of the Urine 230

Quantitative estimation of the mineral ash 233

Quantitative estimation of the chlorides 233

Quantitative estimation of the phosphates 233

Separate estimation of the earthy and alkaline phosphates 234

Quantitative estimation of the sulphates 234

Test for nitrates 230

The Organic Constituents op the Urine . . 230

The nitrogenous constituents of the urine 230

Urea 230

Origin 230

Nitrogenous equilibrium 239

Properties 241

Urea-nitrate 241

Urea-oxalate 241

Synthetic formation 243

Isolation 243

Quantitative estimation 243

Estimation of the preformed ammonia 244

Estimation of the total urinary nitrogen 245

Uric add 240

Origin 240

Properties 249

Tests 250

Isolation 251

Quantitative estimation 251

The xanthin-bases 252

Origin 252

Quantitative estimation 253

Oxalic add and oxaluric acid r 254

Quantitative estimation of oxalic acid 255

Allantoin. . . 250

Isolation 250

Kreatin and kreatinin 257

Properties 257

Tests 258

Synthesis 268

Isolation and quantitative estimation 259



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XIV CONTENTS.

PAGK

The Aromatic Constititekts of the Ubinb 261

The coi^agate sulphates 261

The phenols 262

Qoantitative estimation 263

Indoxyl sulphate 264

Tests 265

Quantitative estimation 266

Skatoxyl sulphate 267

Tests 267

The coi^ugate glucuronates 268

The compound glyoocolls 270

Hippuric acid 270

Properties 271

Synthesis 271

Isolation 272

Quantitative estimation 272

Phenaceturic acid • • 272

Properties 272

Isolation 272

Omithuric acid 2/3

The Arobcatic Oxy-acids 273

Homogentisinic acid 274

Inosit 276

Kynurenic acid 277

The Fatty Acids 278

The volatile fatty acids 278

Isolation and quantitative estimation 2/8

/5-oxybutyric acid 2/9

Test 280

E^imation 281

Diacetic acid 281

Tests 281

Acetone 282

Tests 282

Quantitative estimation 284

Lactic acid 284

Isolation 284

Mono-amino acids ^^

The Neutral Sui^phtr Bodies of the Urine 286

f^^ • ... 287

^y^" 288

Properties

Isolation and estimation

Preparation of '

Estimation of neutral sulphur ^^'^

291
The Carbohydrates

Glucose "

Tests ^^

Quantitative estimation 296



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CONTENTS. XV

PAGE

Lactose 298

Isolation 299

Lflevuloee 299

Laioee 300

Maltose 300

Dextrin 300

Pentoses 300

The Albumins 301

Tests : 302

Estimation 306

The Piobcents op the Urine 307

(Jrochrome 307

Isolation 3O8

UroeiTthrin 3O8

Isolation 309

Urobilin . 309

Tests 309

Ehriich's reaction 310

The blood- pigments 310

Hsematin 311

Hsmatoporphyrin 311

Urornbrohsematin and urofusoohsmatin 312

Melanins 312

The bile-pigments 313

The bile-acids 314

Fats, cholesterin, and lecithins 314

Ferments 315

(iases 315

Ptomains 315



CHAPTER XIII.

THE ANIMAL CELL.

Protoplasm and nucleus TilS

CHAPTER XIV.

THE BLOOD.

General considerations 322

Physical Characteristics of the Blood 323

Color 323

Odor 324

Taste 324

Specific gravity 324

Amount 325

Chemical Examination of the Blood 325

Reaction 325

Chemical composition of the blood as a whole 327



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XVI CONTENTS,

PAOl

The plasma ' 329

Fibrinogen 330

Isolation 330

Properties 330

Serum-globulin 330

Isolation 331

Properties 332

Senim-albumin 332

Separation of the albumins from each other 333

Quantitative estimation of the albumins 333

Serum 334

The coagulation of the blood 335

The fibrin ferment 335

Isolation 336

Properties . 336

Fibrin 337

Estimation 338

Rapidity of coagulation 339

Ferments 339

Glycogen 340

Fat 340

Urea 340

The leucocytes 341

Nucleohiston . ^ 341

Isolation 341

Properties 341

Chemical composition 342

The plaques 343

The red corpuscles 843

Isolation 344

Hiemoglobin and its derivatives 344

Haemoglobin . 344

Globin 345

Hsemochromogen • 346

Oxyhaemoglobin 347

Hsematin 347

Hsemin 349

Carbon dioxide haemoglobin ; 352

Carbon monoxide haemoglobin 352

Nitric oxide hiemoglobin 353

Cyanhaemoglobin 353

Kathaemoglobin 353

Methaemoglobin 353

Haeraatoporphyrin 354

Phylloporphyrin 355

H^ematoidin 355

Haemocyanin 356



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CONTENTS. XVU

CHAPTER XV.
THE LYMPH.

PAOB

The lymph 357

CHAPTER XVI.
THE MUSCLE TISSUE.

Anal^rses of fresh tissue 364

The muscle albumins 365

Myogea 366

Myosin 367

Fennents 370

Muscle stroma 370

Muscle pigments 371

Glycogen 371

Glucose 375

Lactic acid 375

Inosit 378

Kreatin and kreatinin 379

The xanthin bases 381

Gases • 385

Fat 386

CHAPTER XVIL

THE NpiVE TISSUE.

Albumins 388

Neurokeratin 389

Protagon 390

Cerebrin 391

Homocerebrin 392

Encephalin 393

Lecithins 393

The cholesterins 394

Extractives .... 394



CHAPTER XVin.
THE EYE AND EAB.

The cornea 396

The sclerotic 396

The aqueous humor 396

The crystalline lens 397

The vitreous body 398

The retina 398

The choroid 400

The ear 400

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xvm CONTENTS,

CHAPTER XIX.
THE SUPPORTING TISSUES.

PAQl

White fibrous tissue 401

Yellow or elastic tissue 402

Keticulated tissue 402

CJartilage 402

Chondroitin-sulphuric ncid 403

Chondromucoid 404

Albumoid 405

Bone 405

Bone marrow 407

The teeth 407

Adipose tissue 408

Analysis of fat 410

Origin 410

Significance 412

CHAPTER XX.

THE SKIN AND ITS APPENDAGES.

The skin 414

The sweat 416

The sebum 418

The cerumen 419

CHAPTER XXI.

THE GLANDULAR ORGANS.

The liver 420

Albumins 421

Glycogen 424

Ferments ^ 424

Glucose 425

Fat 425

Extractives 426

The pancreas 426

Guanjlic acid 426

The lymph glands 427

The kidneys 428

The mammary glands 428

Themilk 429

General properties 429

Amount 430

Specific gravity 431

Reaction 431

Composition 432

Albumins 433

Fato 437

Lactose 438

Extractives 439



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CONTENTS, XIX

PAQR

Fennents 440

The colostrum 440

The reproductive glands 441

The testicles 441

The semen 442

The spermatozoa 444

The ovaries 445

The ovum 445

ThesheU 446

The albumen 446

The yolk 449

Incubation 453

CHAPTER XXII.

THE DUCTLESS GLANDS.

The thyroid gland 456

The adrenal glands 459



APPENDIX.

Laboratory exercises 463



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CITY Or NlV; YG.X



PHYSIOLOGICAL CHEMISTRY,



CHAPTER I.

INTRODUCTION.

The science of physiological chemistry has for its object the
study of the various chemical processes which take place in the
bodies of animals and plants, and which are more or less intimately
associated with the phenomena of life. As the phenomena of life,
moreover, are essentially dependent upon the transformation of
living matter into non-living matter, and vice veraaj physiological
chemistry deals primarily with the chemical processes of nutrition
in the widest sense of. the term^ Its study therefore comprises a
consideration of the "various suhstpxjfces which are generally desig-
nated as food-8.tttffs/»tfeir origiirjijidir. transformation into living
tissue, and their •altJmJite fate. '•,•'» '.•* . •

Oeneral Oo]Db:^bsition of laving Matter. — Chemical examina-
tion shows .that plants and animals'consist essentially of carbon,
hydrogen, nitrogen, oxygen, sulphur,* phosphorus, chlorine, potas-
sium, sodiiAH;^. calcium, magnesium, apqT Ji*(m — ^that is, of elements
which occur a)^* widely distributed 'i^*. the non-organized world.
In the bodief^ tijC animals and plants. these; elements are built up to
form bodies of -.highly, complex chertniea!*, constitution, which belong
i£\ thfi nlfl^a of^fe^ftiir/s^ /<flrl^ fats. Upon their pres-

ence both animals ,abd plants are di^rident for their existence, and
as jh^fijiodiea are/ constantly li^ng broken do3vn and transformed
into simpler chemical comp6un3s^ as the result of the various raani-
(SfatiDfiB^uTlife, it follows, from the law of the indestructibility
of matter, that for their replacement the living body is forced to
depend upon such simpler matter as is pre-existent. This matter
it IS capable of transforming into the complex substances of which
its tissues are composed.

Forces at Work in the laving World. — The forces which are
at work in effecting these various changes are apparently the same
as those which are operative in the non-organizea world. For the
assumption of special vital forces there seems to be less necessity
the more we come to understand the mechanism of vital plie-
nomena.

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1 8 INTROD UCTION.

Character of Chemical Changes.^-The chemical processes
which are involved in the transformation of non-living matter into
living tissue are qualitatively the same in plants and animals.
Quantitative differences, however, exist, which are sufficiently pro-
nounced to serve as marks of distinction between animals and
plants. Thus plants are capable of evolving from relatively simple
compounds those complex chemical substances which go to form
their structure, while animals apparently do not possess mis power.
They are hence dependent for their existence upon food-stuffs which
are preformed; and the potential energy which animals require
for the functioning of their various organs, and which they trans-
form into kinetic energy, is, as a matter of fact, derived in every
instance, either directly or indirectly, from plant-life. Plants, in
turn, obtain the potential energy which is stored in their tissues from
the kinetic energy of sunlight, and in virtue of this energy can
elaborate those simple chemical substances which are at their dis-
posal as food-stuffs into the complex bodies which constitute their
tissues.

We thus observe that while in plant-life synthetic chemical
processes prevail, analytical processes are foremost in animal life.
These analytical processes, moreover, are largely of the character of
oxidations, while the syntheses which are effected in the bodies of
plants are essentially of the nature ot reductions. But just as syn-
thetic processes are not absoluiel^ t^lfaracterfstid of plant-life, so also
do oxidation-processes occur\.hi*.pTtafits, and-^ritfaetic reductions in
animals. This becomes ^p^^pl^y^rioliceabkt:^ we descend in the
scale of both animal ^nd '"yl^table life. Primitive vegetable
organisms are thus met*with Which, like the highly organized mam-
mal, are almost entirely dependent for their existence upon already
elaborated food-stuffs, aBd*]d\v forms of animal Hfe similarly occur
in which the processes QCjiQ^cition are essentially the same as those
which occur in the highcf.'jjlartts. The differences whi^h thus exist



Online LibraryCharles Edmund SimonA Text-book of physiological chemistry for students of medicine and physicians → online text (page 1 of 53)