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Details the control of enzyme activity in seafood products. These discussions of the special roles of seafood enzymes in post mortem fish metabolism and the quality changes they effect are critical pieces of knowledge in achieving the goal of obtaining maximum value from the species available. The goal must be achieved consistent with responsible use of a resource which we have a strong obligation to use wisely so future generations may also enjoy its benefits. It also provides insights into future directions for research and application of enzymes and is stimulating and thought provoking.

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Seafood Enzymes

Haard , Benjamin K. Be the first to write a review. Trypsin is the key protease activating other pancreatic proteases including chymotrypsin in mammals Stryer and fish Sunde et al. We would expect that any factors that affect trypsin activity should also influence chymotrypsin activity in a similar way, since they are the dominating digestive proteases and their activities are related.


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Interestingly, when trypsin activity correlated to casein levels in the feeds Le Moullac and Van Wormhoudt ; Le Moullac et al. This paper presents studies where variations in the expressions of trypsin and chymotrypsin in the pyloric caeca of Atlantic salmon were induced by different internal trypsin phenotypes, life stages and external starvation, feeding, temperatures factors. The work was performed in order to elucidate how trypsin and chymotrypsin are expressed under different growth conditions, which could be of importance for future growth studies in fish and probably other species in captive cultures and in the wild.

The fish in the other cage was used as control and were provided with a commercial diet according to feeding tables Austreng et al.

This topic provides information about chemical composition of fish

Stomach and pyloric caeca were sampled every third week from eight fish per sea cage, altogether seven sampling times during the whole experimental period. The stomach was used for the determination of pepsin specific activity, and the pyloric caeca was used for the analyses of trypsin and chymotrypsin specific activities see below. The experiment was a part of the work described in Rungruangsak-Torrissen et al. Mixed fertilised eggs were produced from a total of 17 females and 9 males Atlantic salmon, and randomly divided into two groups for incubation at cold 5.

Five replicate tanks 1 m 3 were used for each temperature group. All fish were cultured at natural water temperatures from July until sampling in January In January represented the sampling time when the fish had been in cold water temperatures of 6. The weight of individuals was recorded. The Atlantic salmon parr from the cold temperature start-feeding groups Cold-Cold and Warm-Cold from the previous experiment were reared at a density of about 3 kg per m 3 in 1 m 3 tanks in four replicates from January to August The fish were fed at a restricted ration of 0.

Two sampling times were performed, in January after 3 months rearing in cold temperature 6. At each sampling time, the pyloric caeca samples were collected from 30—40 fish per tank, one sample set was taken during routine feeding and the other set during 5—7 h post-feeding after 7 days starvation following with a continuous re-feeding for 30 min by using automatic feeders. Pepsin in the stomach was determined using the method described by Rungruangsak and Utne Briefly, the stomach was extracted with five times its weight with 10 mM HCl.

One ml of 0. After standing for 10 min at room temperature, the absorbancy was measured spectrophotometrically at nm and compared with l -tyrosine standard curve. The protein content of the crude enzyme extract was determined by Lowry method Lowry et al. The whole pyloric caeca sample was extracted with five times its weight with 1 mMHCl Rungruangsak and Utne Trypsin activity was determined by incubating 0. The reaction was stopped by the addition of 0. The production of nitroaniline was measured spectrophotometrically at nm, and compared with a nitroaniline standard curve.

Chymotrypsin activity was determined by incubating 0. The reaction was stopped and measured at nm in the same way as trypsin.


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  4. Seafood Enzymes: Utilization and Influence on Postharvest Seafood Quality.
  5. Chemical composition of fish.
  6. The fish were immediately killed by a blow to the head before organ sampling. All experiments and procedures were approved by the local animal experiment authority in accordance with the laws and regulations controlling experiments and procedures on live animals in Norway. The work on starvation effect was under responsibility of the National Institute of Nutrition and Seafood Research, in order to see the effect of starvation during low temperature period.

    Seafood Enzymes: Utilization and Influence on Postharvest Seafood Quality / Edition 1

    It should not have an ethical effect, as food availability is low in nature during this time of the year. The starved fish lost their weight by 8. Pepsin specific activity decreased during starvation period, while it took about 2 weeks before trypsin specific activity decreased and maintained at a lower level than the control-feeding group, in a similar way as pepsin specific activity.

    Chymotrypsin specific activity, on the other hand, increased and maintained at a higher level during starvation than during feeding period. Effect of starvation on expressions of pepsin, trypsin, and chymotrypsin in the digestive tract of Atlantic salmon. Arrows with probability values indicate first observations of significantly changing in the enzyme expressions.

    After 26 days of re-feeding, the specific activity of chymotrypsin reduced and that of trypsin increased to normal levels as in the control-feeding group without special requirement for high vitamin and mineral concentrations in the diet, while pepsin specific activity was still at a low level. Re-feeding with low vitamin-mineral diet resulted in a higher trypsin specific activity with specific activities of pepsin and chymotrypsin closer to the normal feeding than re-feeding with high vitamin-mineral diet. There was no difference in weight during the first winter between salmon parr of different trypsin phenotypes within the same temperature control group, except for the group without cold temperature experience warm hatching and warm start-feeding temperatures: Warm-Warm that the fish lacking the cold temperature variant pattern 1: After 3 months starvation in tank scale experiment where no natural foods supply through water, trypsin activity, but not chymotrypsin activity, was still detected at a low level unpublished data.

    Thus the enzyme activities, especially of chymotrypsin, found in starved fish in the present experiment indicated that the fish had consumption. It might be due to the fact that the fish were reared in sea cages and might feed on either natural food or artificial diet from near-by sea cages.

    Among the three proteases studied, alkaline proteases trypsin and chymotrypsin were affected by different feed qualities while acidic protease pepsin was not affected Rungruangsak and Utne Regardless of higher protein or lipid deposition, trypsin specific activity increased in potential rapidly growing fish Sunde et al. Significant relationship between trypsin and chymotrypsin in the pyloric caeca during starvation had been previously observed, and the relationship disappeared after feeding Rungruangsak Torrissen and Male Fish consuming identical quantities of food could grow differently Carter et al.

    It seemed that increased feed conversion efficiency through a similar consumption rate as in diploid fish was due to a decreased chymotrypsin specific activity, while increased feed conversion efficiency through increased consumption rate as in triploid fish was due to a relatively higher increase in trypsin than in chymotrypsin specific activity Sunde et al. Unlike trypsin, higher chymotrypsin specific activity was observed when growth was limited or depressed due to starvation or food deprivation.

    The explanations about specific trypsin variants trypsin phenotypes induced and affecting feed conversion efficiency and growth at different temperatures were described in Rungruangsak-Torrissen et al. Genetic variation in trypsin phenotype and digestive efficiency is important for optimising food utilisation for optimal growth of individuals in nature, especially when food is not abundance. The fish seem to distribute spatially in the temperature zones suitable to their trypsin phenotypes, as observed in Atlantic salmon post-smolts during summer in the Norwegian Sea Rungruangsak-Torrissen and Stensholt Genetic variation in digestive efficiency was dependent on the temperature history of the fish during the very early life stage.

    In addition, the levels of vitamins and minerals in the diet could affect the protease specific activities, since excess of micronutrients showed an adverse effect on the digestive efficiency and growth of the fish. By knowing fish weight, we could compare and predict the growth potential of different fish groups by studying these markers and their relationships. The specific activities of trypsin and chymotrypsin are correlated when growth is limited, while the correlation disappears during a rapid growth i. By knowing more about the chemical quality of the diets fed, these protease markers will increase in their precision in predicting growth and in evaluating the biological quality of the diets Rungruangsak-Torrissen et al.

    Trypsin cleaves protein at the carboxyl side of basic amino acids, lysine and arginine Stryer , which show higher digestibilities than other amino acids Espe et al. Both lysine and arginine seem to elevate plasma insulin levels in salmonids Plisetskaya et al. Arginine is the most potent stimulator of insulin secretion Plisetskaya et al. Absorption rate and level of free amino acids in the plasma influence plasma insulin secretion Rungruangsak-Torrissen and Sundby Insulin stimulates amino acid uptake and protein synthesis especially in the muscle tissues Murat et al.

    Increased luminal secretion of trypsin by decreasing the levels of trypsin specific activity in tissues Rungruangsak Torrissen and Male accompanied by increased plasma insulin level during a period of similar growth resulted in increased growth in Atlantic salmon one month later Rungruangsak-Torrissen et al. Trypsin itself does not directly induce growth, as illustrated by a low correlation coefficient value between the two parameters Sunde et al.

    Trypsin activates chymotrypsin in fish Sunde et al. Chymotrypsin cleaves protein at the carboxyl side of aromatic amino acids phenylalanine, tyrosine, tryptophan, as well as of large hydrophobic residues such as methionine Stryer Increased chymotrypsin expression is however associated with a period when there is a reduction in growth rate. It is not known whether the aromatic amino acids phenylalanine and tyrosine in excess might impact biological systems in a similar way as toxic organic pollutants, such as benzene, polychlorinated biphenyls PCBs and dioxins, as they contain similar free benzene ring s.

    Seafood enzymes : utilization and influence on postharvest seafood quality

    Gene expressions of trypsin and chymotrypsin as well as of different isozymes should be studied closely in connection with other important biological factors affecting protein synthesis rate, such as the multitude of endocrine regulators, in order to gain knowledge of how growth is controlled through or parallel to the digestive processes. Trypsin is the sensitive key protease under condition favouring growth, and genetically and environmentally affected.

    Chymotrypsin, on the other hand, plays a major role when growth is limited or depressed. They are sensitive and reliable biological indicators for comparison of diet quality, digestive efficiency, and the potential growth rate. Further, analyses of muscle growth and muscle quality Rungruangsak Torrissen and Male ; Sunde et al.

    Carotenoid DB: CB

    Any factors feed ingredients Rungruangsak-Torrissen et al. By studying the interactions between these enzymatic markers and with the weight of the animal, a direction of a future change in growth status could be predicted. Practically, these biological parameters could be applicable for studying food utilisation and growth of individuals with different behaviours and in the wild where individual food consumption rate cannot be measured.

    The authors would like to thank E. Bakke and M. Berntsen previously technical assistants for their contributions to the projects. Int J Med Mushr 8: Novel approach for controlling lipid oxidation and melanosis in aquacultured fish and crustaceans: application of edible mushroom Flammulina velutipes extract In vivo. In: Aquaculture Book 1 Muchlisin Z. Application of ergothioneine-rich extract from an edible mushroom Flammulina velutipes for melanosis prevention in shrimp, Penaeus monodon and Litopenaeus vannamei.

    Food Res Int 45 1 : Biochemical intervention of ergothioneine-rich edible mushroom Flammulina velutipes extract inhibits melanosis in the crab Chionoecetes japonicus.

    Seafood Industry Technology - Hudaa Neetoo - TEDxPlainesWilhems

    Food Chem 4 : Ergothioneine from edible mushroom Flammulina velutipes as a potent inhibitor of melanosis in kuruma shrimp Marsupenaeus japonicus. J Food Sci 1 76 : Effects of ergothioneine from mushrooms Flammulina velutipes on melanosis and lipid oxidation of kuruma shrimp Marsupenaeus japonicus. Effect of bisulfate on lobster shell phenoloxidase. Antioxidant and free radical scavenging activities of edible mushrooms. J Food Lipids 9: Phenoloxidase activity of hemocyanin in whiteleg shrimp Penaeus vannamei: conversion, characterization of catalytic properties, and role in postmortem melanosis.

    Inhibition of polyphenoloxidase in mango puree with 4-hexylresorcinol, cysteine and ascorbic acid. Interaction of ergothioneine with metal ions and metalloenzymes. J Medicinal Chem ImageJ Version [Computer software]. Inhibitory effect of enokitake extract on melanosis of shrimp. Fisheries Sci Characterization and tissue distribution of polyphenol oxidase of deepwater pink shrimp Parapenaeus longirostris.

    Food Chem