Extraction of nitrogenous constituents from leguminosae : Solubility of nitrogen from vicia sativa

A study was made of the extraction of nitrogen from vetch seeds ( Vicia sativa ) with solutions of neutral and alkaline salts. Sodium hydroxide extracted most nitrogen and, using a fixed meal: solvent ratio, solubility could be increased by reducing the particle size (dry milling) or increasing the time of extraction and solvent molarity. Stirring was slightly more efficient than shaking. When a fixed concentration of NaOH was used with increasing meal: solvent ratio, the solubility of the nitrogen decreased steadily. Optimum conditions for maximum extraction of nitrogen were established. With sodium chloride minimum solubility of N was found using a concentration of less than 0.01M and maximum with concentrations greater than 0.25M. Extraction with calcium hydroxide solubilised increasing amounts of N up to concentrations of 0.01M, but above this solubility of N decreased.