Increase of Sugar Utilization in Spirogyra by Means of Commercial Fertilizers

LAVOISIER (i) was the first to show that food materials are burned in the body with resulting heat production. He also found that ingestion of food increased oxidation. RUBNER (3) showed that ingestion of meat increased heat production more than did ingestion of fats or carbohydrates. The stimulating effect of meat or protein on metabolism is due to the amino acids, the end products of protein digestion as shown by LUSK (2). SPOEHR and McGEE (4) found that the amino acid, glycine, increased sugar utilization in Helianthus. The object of the present investigation was to determine the effect of fertilizers on the rate of sugar utilization in the plant. Spirogyra porticalis was selected for the experiment. Large quantities of the material were collected from a nearby lake and brought to the laboratory. It was then washed in o.I per cent dextrose solution, and after removing the excess liquid by gently squeezing with the hands, lots of I50 gm. each were weighed out. These batches were placed in flat bottomed dishes, 20 cm. in diameter, in 6oo cc. of o.i per cent dextrose solution. Six hundred mg. of 53 different commercial fertilizers were weighed out and boiled in I5 cc. of water.' After cooling, these fertilizers were added to the different batches of Spirogyra immersed in the sugar solutions. Portions of material to which no fertilizers were added served for controls. A small amount of sugar solution was removed from each of the dishes containing the Spirogyra, and sugar determinations were made according to the method of BENEDICT, immediately and after 40 hours, at the end of the experiments. Before making the determinations at the end of the experiments, water was added to make up for that lost by evaporation. The results of an average of five series of experiments are shown in table I. By comparing the percentages of sugar used, it will be ' We desire to express thanks to the different fertilizer companies who so generously supplied us with the samples of fertilizers used in this investigation.