Characteristics of Trypsin Isolated From Intestines Different of Fish and Correlation Toward Trypsin Activity

Abstract

Trypsin is a protease that breaks protein peptide bonds. Fish intestines can
be used as an alternative raw material for trypsin. Trypsin enzymes from the
intestines of different fish species have different characteristics. This study
aimed to determine the characteristics and stability of trypsin enzyme in
NaCl extracted from fish intestines based on differences in fish species. Trypsin
activity was optimal at 50 °C and pH 8, with specific activity values of 0.5993
U/mg in rabbitfish, 0.3880 U/mg in sharks, and 0.6964 U/mg in flatfish. The
maximum reaction speed (Vmax) was the highest for trypsin from the intestine
of rabbitfish (0.2585 mmol/s), followed by flatfish (0.1042 mmol/s), and
shark (0.0599 mmol/s). The lowest Km value was obtained for trypsin from
sharks (0.4084 mM), followed by flatfish (1.0253 mM), and rabbitfish (4.5952
mM). Trypsin from the intestines of rabbitfish and flatfish was stable in NaCl
solution (concentration 5-30%), as it can maintain a relative activity of more
than 50%. In contrast, trypsin extracted from the intestines of milk fish had
a relative activity below 21%. The average molecular weights of the three
trypsin enzymes were 26.8, 27.2; and 21.9 kDa, respectively. Differences in
the type of fish affected trypsin enzyme activity. Flatfish are omnivorous,
and rabbitfish, as herbivores, have better enzyme activity values than sharks,
as carnivores.