Purification and characterization of trypsin from Luphiosilurus alexandri pyloric cecum

Abstract

Trypsin from L. alexandri was purified using only two purification processes: ammonium sulfate precipitation and anion exchange liquid chromatography in DEAE-Sepharose. Trypsin mass was estimated as 24 kDa through SDS-PAGE, which showed only one band in silver staining. The purified enzyme showed an optimum temperature and pH of 50 °C and 9.0, respectively. Stability was well maintained, with high levels of activity at a pH of up to 11.0, including high stability at a temperature of up to 50 °C after 60 min of incubation. The inhibition test demonstrated strong inhibition by PMSF, a serine protease inhibitor, and Kinetic constants km and kcat for BAPNA were 0.517 mM and 5.0 S−1, respectively. The purified enzyme was also as active as casein, as analyzed by zymography. Therefore, we consider trypsin a promising enzyme for industrial processes, owing to its stability in a wide range of pH and temperature and activity even under immobilization.

Microencapsulation of trypsin from the intestine of yellowfin tuna (Thunnus Albacares)

“…The enzyme activity was lower than the trypsin isolated from sardine and catfish oil. The trypsin isolated from viscera of oil sardine had an activity of 2.28 U/mg [27], while the trypsin isolated from the pyloric caeca catfish had an activity of 2.09 U/mg [22]. This difference is caused by the type of fish and the internal organs of the fish used.…”

Polyurethane Foam Residue Biodegradation through the Tenebrio molitor Digestive Tract: Microbial Communities and Enzymatic Activity

“…ε The calculations of each activity were carried out using the molar extinction coefficients. Protease activity was calculated using the molar extinction coefficient at λ = 410 nm by Ƹ = 8.8 mM −1 cm −1 [ 26 ]; esterase activity at λ = 410 nm by ε = 18.5 mM −1 cm −1 [ 27 ]; lipase activity by λ = 400 nm ε = 14.8 mM −1 cm −1 [ 13 ], and laccase activity at λ = 420 nm by ε = 36 mM −1 cm −1 [ 25 ]. All the activities were expressed in µM −1 g −1 min −1 .…”

Polyurethane Foam Residue Biodegradation through <em>Tenebrio molitor</em> Digestive Tract. Microbial Communities and Enzymatic Activity Involvement

“…The calculations of each one of the activities were carried out using the molar extinction coefficients. Protease activity was calculated using the molar extinction coefficient at λ=410nm Ƹ= 8.8 mM -1 cm -1 [26]; esterase activity at λ=410nm by Ƹ= 18.5 mM -1 cm -1 [27]; lipase activity by λ=400nm Ƹ= 14.8 mM -1 cm -1 [13] and laccase activity at λ=420nm by Ƹ= 36 mM -1 cm -1 [25]. All activities were expressed in µM -1 g -1 min -1 .…”