• Animal cells and systems
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• 제14권2호
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• pp.125-128
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• 2010

This study investigated the effect of different light intensities on first feeding of chub mackerel Scomber japonicus larvae. Fertilized eggs, obtained from LHRHa-induced spawning of captive broodstock, were stocked (60 larvae/l) into twelve 30-1 aquaria under light intensities of 0, 100, 200, 500 and 1000 lx, with three replicate aquaria per treatment. Temperature was maintained at $20^{\circ}C$ and salinity was 35 psu. Larvae were fed the rotifer Brachionus rotundiformis at a density of five rotifers/ml. Feeding incidence was measured as the percentage of larvae with prey in the digestive tract. Feeding intensity was evaluated as the number of prey in the digestive tract of the larvae. Larvae fed in darkness (0 lx) had significantly lower (P < 0.05) feeding incidence ($13{\pm}0.05%$ larvae with prey) and feeding intensity ($1.00{\pm}0.05$ rotifers per larva) than those larvae fed at 100 ($30{\pm}0.07%$, $1.17{\pm}0.09$ rotifers per larva), 200 ($43{\pm}0.08%$, $1.24{\pm}0.11$ rotifers larvae$^{-1}$), 500 ($53{\pm}0.08%$, $1.48{\pm}0.14$ rotifers per larva) and 1000 lx ($60{\pm}0.08%$, $1.38{\pm}0.13$ rotifers per larva). The feeding incidence of S. japonicus larvae increased with light intensity while feeding intensity showed no significant difference (P > 0.05) between light treatments.

• 한국어류학회지
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• 제35권2호
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• pp.113-120
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• 2023

이번 연구에 사용된 고등어는 2022년 1, 3~5, 7~9, 11월에 제주도 주변 해역에서 대형선망, 소형선망어업에 의해 어획된 959개체를 이용하였으며, 전장(Total length)과 체중(Body weight)을 각각 0.1 cm와 0.1 g 단위까지 측정한 뒤, 위를 적출하여 먹이 생물의 크기와 무게를 측정하고 가능한 종 수준까지 분석하였다. 위내용물 분석 결과는 상대중요도지수비를 이용하였으며, 계절과 크기군에 따른 먹이조성 변화를 알아보았다. 고등어의 가장 중요한 먹이생물은 난바다곤쟁이류(Euphausiacea)였으며, 그 다음으로 중요한 먹이생물은 어류(Pisces)로 나타났다. 그 외에, 단각류(Amphipoda), 요각류(Copepoda), 새우류(Caridea), 게류(Brachyura), 두족류(Cephalopoda) 등이 출현하였으나, 0.8% 이하의 상대중요도지수비를 보여 그 양은 매우 적었다. 계절별 위 내용물 조성을 살펴본 결과, 봄, 여름, 가을철에는 난바다곤쟁이류를 주로 섭식하였으며, 여름철에 비율이 가장 높게 나타났다. 겨울철에는 어류가 가장 중요한 먹이생물로 나타났다. 또한 크기 군별 위내용물 조성을 알아본 결과, 모든 크기군에서 난바다곤쟁이류가 가장 우점하였으나, 성장함에 따라 난바다곤쟁이류의 비율은 감소하고 어류의 비율이 증가하는 경향을 보였다. 고등어는 성장함에 따라 개체당 평균 먹이생물의 개체수는 통계적으로 유의한 차이를 보이지 않았으나, 먹이생물의 중량은 통계적으로 유의한 차이를 나타냈다.

• 한국식품과학회지
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• 제31권5호
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• pp.1345-1348
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• 1999

고등어의 저장중 표피 오염 미생물 수를 신속하게 측정하여 신선도 판정을 위한 자료로 활용하고자 ATP bioluminescence assay에 의한 측정가능성을 파악하고자 하였다. 고등어를 $1^{\circ}C$에 저장하면서 표피를 swabbing 방법에 의해 미생물을 분리하여 총균수의 변화와 ATP bioluminescence assay에 의한 RLU 값을 측정하여 상관관계를 측정하여 본 결과 0.90 이상의 regression coefficient를 나타내어 유의적인 관계가 있음을 알 수 있었다. 따라서 ATP bioluminescence assay는 고등어 표피 오염 미생물의 신속 측정 방법으로 적합함을 알 수 있었으며 이 방법을 사용하였을 경우 기존의 48시간 이상 소요되는 전통적인 plate count 방법에 비하여 전처리를 포함하여 30분 이내에 결과를 알 수 있는 매우 신속하고 정확한 측정방법임을 알 수 있었다.

• 한국수산과학회지
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• 제51권5호
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• pp.499-509
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• 2018

This study optimized the bone-softening and fishy odor-reducing process for mackerel Scomber japonicus products using response surface methodology (RSM). The RSM showed that the optimum concentrations of doenjang and citric acid for reducing the fishy odor in bone-softened mackerel were 11.8% and 0.04%, respectively, and the optimum immersion time was 52.2 min. The estimated overall acceptance, salinity, and acidity of the products under these optimum conditions were 7.7 points, 1.1%, and 202.6 mg/100 g, respectively, which were similar to the actual measured values of $7.6{\pm}1.2$ points, $1.0{\pm}0.1%$ and $203.2{\pm}3.8mg/100g$. Moreover, the heating temperature and time for bone-softening based on RSM were $107.3^{\circ}C$ and 4.4 h, respectively. The estimated hardness and proportion of skin removed from the product under the optimal conditions were $161.5g/cm^2$ and 0.09%, respectively, which were also similar to the actual measured values of $171.1{\pm}12.6g/cm^2$ and $0.10{\pm}0.02%$. The optimum bone-softening and fishy odor-reducing process for mackerel consisted of the following steps: thawing (${\leq}10^{\circ}C$, 8 h), filleting, washing/dewatering, immersing in an 11.8% doenjang -0.04% citric acid solution for 52 min, washing/dewatering, heating ($107.3^{\circ}C$, 4.4 h), freezing, depanning, internal and external packaging, and X-ray detection treatment.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2002년도 춘계 수산관련학회 공둥학술발표회
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• pp.175-176
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• 2002

• 한국수산과학회지
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• 제38권5호
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• pp.281-285
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• 2005

Raw meat of mackerel (Scomber japonicus) was salted by refined, sun-dried, bamboo, and KC1-added bamboo salts. Antimutagenic activity on N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) in Ames test and growth inhibitory effects of AGS human gastric and HT-29 human colon adenocarcinoma cells were investigated using methanol extracts of the salted mackerels. Mackerel salted sun-dried, bamboo, and KC1-added bamboo salts used increased the antimutagenic activities against MNNG, however, the sample treated with refined salt reduced the antimutagenic activity. Inhibitory effects of the salted-mackerels on the growth of human cancer cells were increased as dose dependent pattern. Mackerel salted with refined salt activated the growth of AGS human gastric adenocarcinoma cells, but mackerel salted with sun-dried, bamboo, and KC1-added bamboo salts kept or increased anticancer effect compared to the raw mackerel. Mackerel salted with KC1-added bamboo salt led to the highest antimutagenic and anticancer activities. These results suggest that antimutagenic and anticancer effects of mackerel during manufacturing of the salted-mackerel could be enhanced by using different kind of salts such as bamboo, or KC1-added bamboo salts.

• 한국수산과학회지
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• 제55권6호
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• pp.946-953
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• 2022

Using the management strategy evaluation methods and data on the Korea chub mackerel Scomber japonicus where the state-space logistic production model is used as the operation and the estimation model respectivley, we examined the effects of both Dorn's rule, α and the buffer value for ABC (allowable biological catch), which are used by the Korea fishery managers for decision rules. We set scenarios that have different pairs of buffer and α values, which include those currently used in the management in Korea. Under each sceanario, we projected the fish population biomass until year 2050, during which ABC is determined in each year with the decision rule. We used three kinds of performance measures: (i) whether the biomass in 2050 is overfished; (ii) the average of annual yields over the simulation period; and (iii) the variability of annual yields over the period. We found that the current practice (buffer=0.9, and α = 0.05) resulted in the best performance in terms of avoiding the "overfished" status. However, the current practice failed to reach the maximum average of the annual yields and led to larger uncertainty in the annual yields.

• Fisheries and Aquatic Sciences
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• 제17권2호
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• pp.175-180
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• 2014

The present study was conducted to characterize physicochemical properties of chub mackerel bones (CMB) to evaluate its potential as a food resource. The proximate composition of CMB showed 40.4% moisture, 13.8% crude fat, 15.2% crude protein, and 28.7% ash. The major minerals in CMB were calcium (26.27 g/100 g) and phosphorus (15.88 g/100 g). The amino acids were rich in glycine, proline, glutamic acid, and alanine. The contents of total and neutral lipids, glycolipid and phospholipid were shown to be 16.05%, 95%, 2.32%, and 3.15%, respectively. The major fatty acids were C22:6, C16:0, C18:1, C20:5, C18:0, C17:0, C14:0, C20:1 in order. The fatty acid contents of total and neutral lipid were in a range of 39.25% and 44.54% for saturated and 33.61% and 34.05% for polyunsaturated, respectively. The breaking strength and hardness of intact CMB were 10.01 and $50.03kgf/cm^2$, whereas those of CMB heated for 45 min at $121^{\circ}C$ were 0.40 and $1.94kgf/cm^2$, respectively.

• Fisheries and Aquatic Sciences
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• 제24권4호
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• pp.139-152
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• 2021

The main purpose of this study is to fit catch-per-unit-effort (CPUE) data about Korea chub mackerel (Scomber japonicus) stock with a state-space production (SSP) model, and to provide stock assessment results. We chose a surplus production model for the chub mackerel data, namely annual yield and CPUE. Then we employed a state-space layer for a production model to consider two sources of variability arising from unmodelled factors (process error) and noise in the data (observation error). We implemented the model via script software ADMB-RE because it reduces the computational cost of high-dimensional integration and provides Markov Chain Monte Carlo sampling, which is required for Bayesian approaches. To stabilize the numerical optimization, we considered prior distributions for model parameters. Applying the SSP model to data collected from commercial fisheries from 1999 to 2017, we estimated model parameters and management references, as well as uncertainties for the estimates. We also applied various production models and showed parameter estimates and goodness of fit statistics to compare the model performance. This study presents two significant findings. First, we concluded that the stock has been overexploited in terms of harvest rate from 1999 to 2017. Second, we suggest a SSP model for the smallest goodness of fit statistics among several production models, especially for fitting CPUE data with fluctuations.

• 한국수산과학회지
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• 제50권6호
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• pp.837-840
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• 2017

We developed a method to rapidly evaluate the freshness of fish using a sensor gas chromatography (SGC) system. Mackerel Scomber japonicus was stored at $4^{\circ}C$ for 12 days to create an environment similar to the natural decomposition process. Trimethylamine (TMA) content in mackerel muscle was measured at 3-day intervals using a spectrophotometer. The gas-phase concentration of TMA in whole mackerel was also determined using an SGC system. The muscle TMA content increased over time during storage, as did the gas-phase concentration of TMA. Therefore, this study demonstrated that an SGC system can be used to rapidly measure the gas-phase concentration of TMA in fish during processing.