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NTENTS 



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SECTION VIII.— PROTEINS 3°! 



General properties 302 



Microchemical reactions 308 



Proteins as colloids 308 



Decomposition products ......... 313 



Amino acids obtained as cleavage products of proteins . . -315 



Constitution of the protein molecule 3^8 



jk^ Polypeptides 3^9 



B Occurrence of amino acids in plants 321 



Classification of protems 322 



Comparison between vegetable and animal proteins .... 328 



Extraction ot proteins 330 



Synthesis of proteins in the plant 333 



Synthesis of amino acids in the plant 337 



Estimation of nitrogen 340 



SECTION IX.— ENZYMES 344 



Classification 348 



Isolation 349 



Chemical constitution 349 



Properties . 350 



Colloidal nature of enzymes 351 



Mode of action 352 



Activators 354 



Paralysers 356 



Anti-enzymes ........... 358 



Enzymes and the laws of mass action 361 



Consideration of certain types of enzymes 365 



Lipase ........ .... 366 



Isolation 367 



Quantitative determination of activity 368 



Diastase 368 



Isolation .......... 369 



Quantitative determination of activity 370 



Proteases 370 



Isolation 370 



General considerations ........ 372 



Tryptophane reaction 373 



Quantitative determination of activity 374 



Zymase and alcoholic fermentation 374 



Isolation of zymase ...... . . 377 



General considerations ........ 377 



Identification of ethyl alcohol ... ... 382 



Quantitative dttemiination of activity . ... . . 383 



Occurrence of alcohols in plants 385 



Inosite 387 



Manufacture of ethyl alcohol 389 



Oxidases 390 



Isolation .......... 392 



Peroxidase .......... 392 



Preparation ......... 392 



Identification 393 



General considerations 394 



INDEX 399 



