Optimizing ammonia pressurization/depressurization processing conditions to enhance enzymatic susceptibility of dwarf elephant grass

An ammonia pressurization/depressurization process was investigated to evaluate the potential of producing reducing sugars from dwarf elephant grass, a warm-season forage. Moisture, temperature, and ammonia loading affected sugar yield (p<0.0001). At optimal conditions, ammonia processing solubilized 50.9% of the hemicellulose and raised the sugar yield (percentage of theoretical) from 18 to 83%. Glucose and xylose production were increased 3.2-and 8.2-fold, respectively. The mild processing conditions of the ammonia treatment (90–100°C, 5 min), the low enzyme loading (2 international filter paper units/g), and the short hydrolysis time (24 h), greatly enhance the potential of using for ages to produce sugars valuable for several applications.

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