EVALUATION OF COMBINED PROCESSES: CHITIN PURIFICATION FROM SHRIMP (Penaeus sp) AND GRASSHOPPER (Sphenarium purpurascens) EXOSKELETONS

Abstract

Background. Chitin is found in high concentration in insects, this being a new source of exploitation, due to the similarity in the content of chitin in exoskeletons of crustaceans compared to insects, especially those considered pests. Objective. Evaluate and compare the biological process of solid medium fermentation (SMF) combined with three treatments: ultrasonication, chemical and enzymatic hydrolysis in the purification of chitin from shrimp (Penaeus sp) and grasshopper (Sphenarium purpurascens) exoskeletons. Methodology. It consisted of the implementation of a pretreatment by fermentation in a solid medium (SMF) with chitinous samples (shrimp and grasshopper) combined with ultrasonication (20 kHz, 750 W, 120 min, 30 °C, 1/20 p/v), hydrolysis chemical (0.4 M NaOH, 0.6 N HCl, 38% NaClO, 1/15 p/v, 25 °C, 4 h) and enzymatic (Alcalase® 2.4L, 1:2 E:S, pH 7.5, 70 °C, 150 rpm, 300 min). Results. The combined treatments of SMF-ultrasonication, SMF-chemical hydrolysis, and SMF-enzymatic hydrolysis showed a higher percentage of deproteinization (84.82, 94.67, and 80.45%) and demineralization (82.12, 95.58, and 52%) with shrimp exoskeletons compared to shrimp exoskeletons grasshopper percentages (76.38, 92.04 and 78.71%) and (79.39, 95.37 and 51.79%) respectively. Implications. The chemical treatment generated greater protein and mineral removal compared to the other treatments, reaching yields of 54.45% in shrimp and 51.88% in grasshoppers. Conclusion. Ultrasonic waves extracted chitin in a shorter time (2h) with yields of 74.43% in shrimp and 78.02% in grasshoppers, reducing the amount of water.