Leaf protein from ammonia-treated dwarf elephant grass (Pennisetum purpureum Schum cv. Mott)

Proteins can be an excellent byproduct of the biorefining of lignocellulosic materials. In this work, extraction conditions for the white leaf proteins (cytoplasmic) of ammonia-treated dwarf elephant grass were established to obtain a protein juice suitable for the production of leaf protein concentrates. A calcium hydroxide solution was used as extracting agent, at several solid-liquid ratios, pHs, temperatures, and times. Extractions were carried out in Erlenmeyer flasks containing 5 g (dry basis) of forage with constant agitation (100 rpm). The soluble protein content was determined by the Lowry method. Optimal extraction conditions for the ammonia-treated forage were 12.60 pH, 1:10 solid-liquid ratio, 90 degrees C, and 30 min extraction time, resulting in 52.65% extraction yield. The ammonia treatment significantly increased (p<0.05) the release of proteins from the fibrous matrix, facilitating their extraction.