October 6, 1922] 



SCIENCE 



397 



have been made with auiline, methyl and etliyl 

 amines, benzoic benzamide, anthranilic acid and 

 hippuric acid. These substances collectively eon- 

 tain tlie amino and earboxyl groups both singly 

 and in different combinations but none of thein 

 showed any favorable influence upon the activity 

 of salivary or pancreatic amylase when tested 

 under what are now regarded as standai'd condi- 

 tions for the activity of these enzymes. The re- 

 sults fail to furnish any support for the view 

 that certain organic groupings as such activate 

 amylolytie action. They make it mmli more 

 proba:ble that the favorable influence of a-Mnino 

 acids upon amj'lases is to be attributed primarily 

 if not entirely to their effect in preserving the 

 enzyme from hydrolytie destruction. 



Effect of amino acids in retarding the hy- 

 drolytic decomposition of an enzyme (pancreatic 

 amylase). H. C. Sherman and Florence 

 Walker. The extent of the deterioration of this 

 enzyme when allowed to stand in solution for 

 different lengths of time and at different tempera- 

 tures with and without the addition of amino acid 

 has been determined. The higher the temperature, 

 up to the point at which coagulation begins, or 

 the longer the time of heating, the more marked 

 was the favorable effect of the added amino acid, 

 thus confirming the ^iew that the enzyme in its 

 chemical composition either is a protein or con- 

 tains protein as an essential constituent, and that 

 the added amino acid exerts its favorable influ- 

 ence by checking the hydrolytie destruction of 

 the enzyme. 



Catalytic action of phosphates on the separate 

 and simnitaneous oxidation of glucose and butyric 

 acid with peroxide. Edgar J. Witzemann. 



Energy expenditures hy women during horizon- 

 tal wallcing at different speeds. H. Monmouth 

 Smith and Dortha B. Bailey. Using the 

 Douglas-Haldane method of measuring the gase- 

 ous exchange the eiu'rgy expenditure of nine 

 women was determined when standing and walk- 

 ing at speeds of 30, 60 and 90 meters a minute. 

 The average standing expenditure was 0.600 

 calorie per minute per square meter of body sur- 

 face computed by Du Bois height-weight chart. 

 The total increase for the walking over the 

 standing values showed an average expenditure 

 for the nine subjects of 0.527, 0.489 and 0.552 

 gram-calorie per horizontal kilogrammeter for 

 the speeds of 30, 60 and 90 meters per minute 

 respectively. Seven out of the nine subjects 

 showed a greater energy expenditure per hori- 

 zontal kilogrammeter at 30 meters per minute 

 than at 60. The menstrual period was appar- 



ently mthout effect on either the standing or 

 walking motatoolisni. 



The suhstitxitions of glass electrodes for the 

 hydrogen electrodes in electrometric titration. 

 Walter S. Hughes. 



Oxidation-reduction potentials and the stability 

 of vitamin C. Victor K. LaMer. The differ- 

 ence in acidity is insufficient to account alone for 

 the niuch greater stability of vit;'min C to heat 

 in the case of tomato and citrus fruit juices com- 

 pared to tliat of cabbage juice wJiere almost com- 

 plete destruction occurs on boiling for one hour 

 in the absence of air. The oxidation-reduction 

 potentials of these juices, freshly expressed, were 

 determined electrometrically in the absence of 

 atmospheric oxygen. The potentials, Avlien cor- 

 rected for pj^, indicate that the stability of the 

 vitamin depends upon the natural oxidizing or 

 reducing condition of the juice as well as upon 

 the opportunities that are afforded for atmos- 

 pheric oxidation. 



Flour strength as influenced hy the addition of 

 diastatic ferments. F. A. Collatz. Tlie opti- 

 mum activity for the diastase in malt flour with 

 raw wheat starch as a substrate was found at 

 Pjj 4.26 and at a temperature of 65 degrees C. 

 This activity was apparently constant over the 

 period of digestion. The reducing sugars 

 increased proportionately to the amount of dias- 

 tase added. The viscosity of the digestion mix- 

 ture (plus lactic acid) decreased with increasing 

 amounts of added diastase and also with the time 

 of digestion. This decrease is apparently not 

 due to the salt effect. The gas producing ca- 

 pacity of strong flours is not increased by dias- 

 tase, but Avith weak flours the reverse is the ease. 



Changes in hydrogen-ion concentration of fer- 

 menting dough. (By title). F. A. Collatz. 



The synthesis of 'vitamins by molds. V. E. 

 Nelson, Ellis I. Fulmek, T. G. Heller and 

 W. W. DuECKER. Yeast grown on medium F is 

 about 60 per cent, as potent in vitamin B as 

 Fleischmann 's yeast; the above synthetic yeast will 

 cure polyneuritis in pigeons. Air drying destroys 

 about 30 per cent, of the vitamin B potency of 

 yeast. Aspergillus niger and Fenicillium expan- 

 sum synthesize vitamin B when grown on Rnulin 's 

 medium but do not synthesize vitamin A. The 

 potency in vitamin B is about the same as that 

 of our synthetic yeast. Sclerotinea cinerea shows 

 vegetative growth on medium F but does not 

 sporulate. The mycelia, according to incomplete 

 data, shows no vitamin B. The work is being 

 continued. 



The use of Tcelp in the preparation of a diet 



