• Applied Biological Chemistry
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• v.50 no.4
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• pp.308-315
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• 2007

For the effective use of squid processing by-products as food resources, the distribution and the extraction condition of endoprotease and exopeptidase from viscera of Illex argentinus were investigated. Crude protein and lipid contents of viscera of Illex argentinus were 17.2% and 16.9%, respectively. Regardless of kinds of extraction solution (water, 1% NaCl, 1% KCl and 1% NaCl- KCl) and extraction times (1-20 h), endoprotease activities from viscera of Illex argentinus on Hb, casein and azocasein (pH 6.0) were higher than those on casein and azocasein of the other pHs, thus indicating that the distribution of protein hydrolysing protease is distinctive in the weak acid pH range. Exopeptidase activities against LeuPNA and ArgPNA at pH 7.5 were relatively higher than endoprotease activity of the same pH. The results suggested that exopeptidase among proteases from viscera of Illex argentinus was reasonable for application in food industry compared to endoprotease. The activity in enzymes from viscera of Illex argentinus was the highest in the exopeptidase extracted with deionized distilled water at room temperature for 6-8 h. The optimal reaction conditions of crude enzyme from viscera of Illex argentinus were 7.5 for pH and $50-55^{\circ}C$ for temperature.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.41 no.3
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• pp.176-181
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• 2008

To evaluate the effective use of endoprotease from squid viscera as a food processing aid, various methods of fractionating endoprotease from viscera of the Argentina shortfin squid (Illex argentinus) were evaluated. The endoprotease-positive fractions of each fractionation were fraction II (30-40%, w/w) with cold acetone, fraction IV (50-60% saturation) with ammonium sulfate, fraction UF with anion exchange chromatography, and fraction II (15-24 kDa) with gel filtration. The specific activities (approximately 25 U/mg) of the fractions using ammonium sulfate and gel filtration were higher than the others. Total azocaseinolytic activity and recovery of the positive fraction using gel filtration were 806.95U and 37.82%, respectively, and were the highest among the positive fractions. Based on the results, gel filtration was the most efficient method for fractionating endoprotease from the viscera of Illex argentinus.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.6
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• pp.934-941
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• 2020

The spatial and temporal catch variations of Argentine shortfin squid Illex argentinus in the Southwest Atlantic Ocean (SWA) were analyzed using Korean squid-jigging fishery data collected through electronic reporting system (ERS) from 2016 to 2020. The ERS linked with GPS has been implemented for collecting fishing data from all Korean fishing vessels operating in international waters since November 2015. The fishing period of the Korean squid-jigging fishery in the SWA runs from early summer to autumn (December to June) in the Southern Hemisphere. The fishing ground was extended from 42°S to 48°S along the Patagonian continental shelf and slope, and the main fishing ground was formed around the Falkland Islands. The yearly catch per unit effort (CPUE) of I. argentinus fluctuated between 1.69 and 7.53 tons/day. In this study, during the fishing season, a south and westward shift on the fishing ground was observed indicating the feeding migration of the south Patagonian stock. The shift in monthly fishing centroids differed according to fishing season. The gradual southward shifts of fishing centroids were observed in the catch years (2017 and 2018), whereas unapparent shifts in fishing centroids were observed in the low catch years (2016 and 2019).

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.40 no.4
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• pp.282-294
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• 2004

Catches of Argentine shortfin squid Illex argentinus showed a sharp decrease, reaching 99,000ton in 1993 and 56,700ton in 1994, and then increased again reaching 130,300ton in 1997 from 78,600 ton in 1996. The Korean squid jigging fishery around Falkland for Illex argentinus commences usually its operation in January and lasts August and peak in catch was showed from March to May. To elucidate possible environmental effects on their abundance during the main fishing season in 1993-1994 and 1996-1997, sea surface temperatures were used as an indicator of the position and strength of the oceanographic structures in the Southwestern Atlantic Ocean. The high catch and catch per unit effort of Illex argentinus was showed when the Faliland Current was not affected in the fishing area in 1993 and 1997. But they were sharply decreased from the middle of April 1994 and the late of April 1996 when the Faliland Current directly affects the fishing ground.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.8
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• pp.1009-1017
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• 2008

For the effective use of exopeptidase from squid viscera as food processing aids, the viscera of Argentina shortfin squid (Illex argentinus) were fractionated by various methods such as acetone treatment, ammonium sulfate treatment, anion exchange chromatography, and gel filtration. The positive exopeptidase fractions were obtained from the fraction II treated by cold acetone ($30{\sim}40%$, w/w), the fraction V by ammonium sulfate ($60{\sim}70%$ saturation), the fraction II (0.2 M NaCl) by anion exchange chromatography, and the fraction I ($30{\sim}50\;kDa$) by gel filtration. The specific activities of positive fractions from viscera of I llex argentinus against substrates were higher to LeuPNA than to ArgPNA. Total activity and recovery against LeuPNA of positive fraction by gel filtration were 1,867 U and 30.69%, respectively, which were the highest among those of positive fraction. The results suggested that the gel filtration chromatography method was the most efficient method for the fractionation of exopeptidase from viscera of Illex argentinus.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.2
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• pp.135-143
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• 2014

Exopeptidase active fractions from the hepatopancreas of the Argentina shortfin squid Illex argentinus, were obtained with acetone (AC 30-40%), ammonium sulfate (AS 60-70% saturation), anion exchange chromatography (AE-II, 0.2 M NaCl) and gel filtration chromatography (GF-I, 30-50 kDa) fractionation methods. A bitter peptide solution that has a bitterness equivalent to that of 2% glycylphenylalanine and prepared by tryptic hydrolysis of milk casein, was treated with the exopeptidase active fractions. The GF-I fraction was the best based on aminopeptidase activity (35.3 U/mg), percentage of recovery (30.7%) and a sensory evaluation (1.7). The amount of released amino acids increased as incubation time increased, and the bitterness of the enzyme reaction mixtures decreased. Incubation with the GF-I fraction for 24 h resulted in the hydrolysis of several peptides as revealed by the reverse-phase high performance liguid chromatography profile, with three peaks (3, 5 and 6) decreasing in area (%) and three peaks (1, 2 and 4) increasing in area (%). Therefore, the GF-I fraction appeared to be ideally suited to reduce bitterness in protein hydrolysates by catalyzing the hydrolysis of bitter peptides.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.4
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• pp.595-600
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• 1997

The oil content and composition of squid visera were determined to obtain data for utilization of this by-product. There was no significant difference in the glycolipid (GL) and phospholipid (PL) content in Illex argentinus and Todarodes pacificus, but neutral lipid (NL) was different (p<0.05). The viscera oil of I. argentinus contained $30.50\%$ total lipid which consisted of $96.24\%$ NL, $2.63\%$ GL, $2.37\%$ PL, and contained $644mg\%$ cholesterol. The viscera oil of T. pacificus contained $30.20\%$ total lipid which consisted of $94.82\%$ NL, $2.85\%$ GL, $2.34\%$ PL, and contained $1,224\;mg\%$ cholesterol. The NL, GL and PL of viscera oil in I. argentinus mainly consist of triglyceride $(44.01\%)$, esterified steryl glycosides $(58.95\%)$ and phosphatidyl cholines $(32.36\%)$, respertively. Those of viscera oil in T. pacificus mainly consist of triglyceride $(39.63\%)$, monogalactosyl diglycerides $(51.67\%)$ and phosphatidyl cholines $(31.98\%)$, respectively. The major fatty acids of the viscera oil of I. argentinus and T. pacificus were C16 : 0, $C16\;:\;0,\;C18\;:\;1\omega9,\;C20\;:\;4\omega6,\;C20\;:\;5\omega3,\;C22\;:\;6\omega3$. In Illex argentinus, the fatty acids of NL mainly were $C16\;:\;0,\;C18\;:\;1\omega9,\;C20\;:\;4\omega6,\;C20\;:\;5\omega3,\;C22\;:\;6\omega3$. PL were $C16\;:\;1\omega7,\;C20\;:\;5\omega3,\;C22\;:\;6\omega3$ and GL were $C18\;:\;1\omega9,\;C20\;:\;5\omega3,\;22\;:\;6\omega3$. The major fatty acids of NL in T. pacificus were $C16\;:\;0,\;C18\;:\;1\omega9,\;C20\;:\;4\omega6,\;C20\;:\;5\omega3,\;C22\;:\;6\omega3$, PL were $C16\;:\;1\omega7,\;C20\;:\;5\omega3,\;C22\;:\;6\omega3$, and GL were $C18\;:\;1\omega9,\;C20\;:\;5\omega3,\;C22\;:\;6\omega3$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.4
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• pp.517-525
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• 2021

Trawl fishing is a major concern worldwide, and there is considerable debate about its impact on marine ecosystems. In this study, we used the vessel monitoring system (VMS) data collected in the southwest Atlantic Ocean from 2016 to 2019 to estimate the fishing effort and trawled area. Spatial distribution of trawl activities according to the latitude and longitude and the hotspots where fishing was concentrated each year were identified. Trawling activities of the Korean vessels were mainly distributed between 40-52°S and 56-63°W. The species caught during the fishing period comprised five Cephalopoda, three Chondrichthyes, ten Osteichthyes, and other fish. The Argentine hake Merluccius hubbsi and Argentine shortfin squid Illex argentinus were the dominant species in the catch.