386 The Philippine Jowimal of Science mi 



Table VII. — Destruction of dextrose in lime solution without enzyme. 



Time. 



Dextrose. 



Alka- 

 linity, 

 gram 

 CaO per 

 100 cc. 



Brix. 



Present. 



De- 

 stroyed. 



Hrs. 

 

 12 

 24 

 36 

 48 

 60 

 72 



Per cent. 

 8.0 

 6.0 

 8.2 

 2.1 

 1.6 

 1.3 

 0.9 



Per cent. 

 0.0 

 38.0 

 60.0 

 73.0 

 80.0 

 84.0 

 88.9 



0.280 



9.7 



0.215 



9.3 



0.182 



9.2 



0.145 



9.1 



Table VIII. — Destruction of levulose in lime solution without enzyme. 



Time. 



Levulose. 



Alka- 

 linity, 

 gram 

 CaO per 

 lOOcc. 



Brix. 



Present. 



De- 

 stroyed. 



Hrs. 





 12 

 24 

 36 

 48 

 60 

 72 



Per cent. 

 6.7 

 5.3 

 4.3 

 3.8 

 2.8 

 2.4 

 2.0 



Per cent. 

 

 20.1 

 35.8 

 50.0 

 58.2 

 64.0 

 70.1 



0.302 



10.0 



0.201 



9.9 



0.151 



9.7 



0.106 



9.5 



Tables IV and V serve to bring out clearly the remarkable 

 activity of the enzyme present in nipa, and explain why 

 certain samples of juice, uniformly alkaline with lime, gradually 

 decreased in sugar content. Experiments also showed that nipa 

 sap containing palm tissue suffered an even more rapid loss of 

 sucrose by enzyme action than did the sugar solutions prepared 

 in the laboratory. This was to be expected, as the juice contains 

 a variety of constituents that might well activate the enzyme. 



The presence of this active enzyme in the nipa palm has a very 

 important bearing on the commercial production of sugar. A 

 loss of from 5 to 10 per cent of the total sugar due to this cause 

 might be a deciding factor between success and failure, and such 

 a contingency must be guarded against in any commercial under- 

 taking. It would be less important if all juice could be collected 

 from long stalks, flowing freely, and secreting a sap compara- 

 tively free from enzyme. However, this is impossible under 

 the conditions that prevail in practice. The contents of many 



