ENZYMES 157 



These enzymes apparently destroy proteolytic systems which prevent 

 the healing of such wounds. 



A sterile papain hydroly/ate of meat placed in a solution of salt, 

 glucose, and vitamins has been used in the treatment of chronic 

 starvation in India. Similar preparations of protein hydrolyzates are 

 now becoming increasingly important in feeding malnourished pa- 

 tients in certain types of postoperative cases and in diseases of the 

 digestive tract. 



Mixtures of amylases and maltase, called diastases, are used in 

 analytical chemistry for starch determinations. The method employed 

 measures the increase in reducing sugars resulting from the enzymic 

 hydrolysis of starch. This method is more specific than one that 

 measures the increase of reducing sugars after hydrolysis by acid. 



Uricase is used in a method for the determination of uric acid in 

 blood, and urease is employed for the determination of urea in blood 

 and urine. The ammonia formed by urease is determined either by 

 titration or by the color formed with Nessler's solution. 



Sucrose and raffinose are determined in mixtures of sugars and in 

 sugar products by polarimetry before and after treating the solutions 

 with sucrase and melibiase. The activity of phosphatase present in 

 milk is used as a measure for the efficiency of pasteurization. The 

 inactivation temperature and time needed to destroy phosphatase 

 activity are such that pathogenic bacteria in milk are killed before the 

 enzyme is completely inactivated. 



REFERENCES 



Outlines of Enzyme Chemistry, second edition. J. B. Neilands and P. K. Stumpf. 



John Wiley & Sons, New York, 1958. 

 Enzymes. M. Dixon and E. C. Webb. Academic Press, New York, 1958. 

 The Enzymes. Edited by P. D. Boyer, H. A. Lardy, and K. Myrback. Academic 



Press, New York, 1958. 

 Methods in Enzymology. Edited by S. P. Colowick and N. O. Kaplan. Academic 



Press, New York, 1955-1957. 

 Advances in Enzymology. Edited by F. F. Nord and C. H. Werkman. Interscience 



Publishers, New York, annual volumes beginning in 1941. 



