Trypsins from fish processing waste: characteristics and biotechnological applications – comprehensive review

Study on enzymes of industrial interest in digestive viscera: Greater amberjack (Seriola dumerili)

“…Similar reports have showed the optimum activity of enzymatic crude extracts from Brownstripe red snapper Lutjanus vitta [26], Japanese sea bass L. japonicus [20] and pirarucu A. gigas [8] in the range from 8.5 to 10.0. These results are consistent with those reported for trypsin from fish species in literature [6]. Trypsin stability to pH variation was similar to the findings reported by Silva et al [7] for silver mojarra D. rhombeus remaining stable in a range of alkaline pH (8.5-11.0) and being unstable in pH below 8.5 and showing negligible activity at pH 4.5, while Cai et al [20] reported recovery of activity for Japanese sea bass L. japonicus in the pH range from 7.0 to 11.0.…”

“…One of the characteristics of fish proteases is to have a higher affinity to the specific substrate (lower K m ) when compared to the enzymes from other sources, such as bovine trypsin; this is mainly due to differences in the region of substrate breakdown [6]. The K m is used to assess the affinity of the tested enzyme to the substrate and constitutes one of the characteristics observed by the industry during the prospection process for novel commercial enzymes.…”

“…Guerrero-Zárate et al [13] reported optimum temperature of 60 °C for alkaline proteases (trypsin and chymotrypsin) in juveniles of tropical gar A. tropicus. For affecting the folding of proteins due to the breaking of disulfide bonds, the temperature influences the enzymatic activity [6]. Because of less disulfide bonds, when compared to trypsin, chymotrypsin becomes more sensitive to the temperature.…”

“…The proteases recovered from these sources have physicochemical and kinetic properties similar to the mammalian enzymes commonly employed in the production processes of the textile, pharmaceuticals and foods [6]. Moreover, the use of neglected fish viscera contributes to reducing environmental damage.…”

Faecal characteristics as markers of Chelonia mydas feeding

“…For intestinal enzymes, pH 10 and 40°C were optimal for trypsin, whereas for alkaline protease found in red-eared slider turtle pH 7.0-8.5 at 50°C were optimal 22 . Stability over a range of pH and temperature values is common to most trypsin isoforms reported in fish 24 , and similar optimal conditions at pH 10.5 and 40°C in grey triggerfish, Balistes capriscus 25 and pH 10 at 30-35°C in Siamese fighting fish, Betta splendens 26 have also been reported. This enzyme is most active in pancreas, followed by anterior, middle and posterior sections of intestine 22 .…”