• Journal of Food Hygiene and Safety
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• v.38 no.3
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• pp.140-151
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• 2023

This study investigated pesticide residues in 367 agricultural products from local food markets in Ulsan. Pesticide residues in these samples were analyzed using multi class pesticide multi-residue methods on the Korean Food Code for 350 pesticides using GC-MS/MS and LC-MS/MS. Residual pesticides were detected in 79 (21.5%) samples and exceeded maximum residual limits (MRLs) in 4 (1.1%) samples (chwinamul, narrow-head ragwort, green onion, apricot). The range of the hazard index (%) was 0.0000-63.1043%, and values for the pesticides that violated the MRLs were 63.1043 (green onion), 0.5417 (chwinamul), 0.0684 (apricot), and 0.0100 (narrow-head ragwort). This risk assessment study showed that the values of hazard index (%) were less than 100%, indicating that the consumption of these local agricultural food products was not harmful for human health.

• Fisheries and Aquatic Sciences
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• v.26 no.10
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• pp.593-604
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• 2023

Post-harvest handling and hygienic level of aquatic products significantly affect the quality and level of safety. Cold chain control is one of the determining factors for the quality of fish and the bacterial community that grows on the fish. Identification of spoilage bacteria and pathogens in aquatic products must be made because it will determine the physical and chemical quality. A molecular identification method with high sensitivity is the solution. This study aims to identify the quality of fish and bacterial communities that grow. The research procedures included sample collection, pH measurement, drip loss measurement, transportation and cold storage treatment, DNA extraction, DNA sequencing, sequence analysis, and bioinformatics analysis. The conclusion obtained from this study is that the simulation of the cold chain system applied to eastern little tuna does not significantly affect changes in the water activity value, pH, and drip loss. The insignificant change indicates that the eastern little tuna samples are still in good quality. The bioinformatics analysis showed the highest diversity and abundance of the bacterial community came from the Gammaproteobacterial class.

• Fisheries and Aquatic Sciences
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• v.24 no.4
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• pp.153-162
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• 2021

In this study, a fish metabolic accelerator (a combination of butaphosphan and cyanocobalamin [BPC]) was injected into the muscle of the olive flounder, Paralichthys olivaceus, to investigate its effect on immunity and stress in fish maintained at low temperatures. A single dose of BPC was injected (100 mg/kg body weight) into the olive flounder, and its immunity and stress were observed after one and two weeks. Immunity tests revealed the presence of lysozyme (LZM), nitroblue tetrazolium (NBT), myeloperoxidase (MPO), anti-protease (AP), glutathione peroxidase (GPx), and total immunoglobulin (TIg). BPC injection was found to increase immunity activity compared to the control group. In particular, there was significantly high GPx activity. There was similarly high activity for MPO and GPx in the first week following the injection, followed by significant differences between the BPC-injected and control groups in the second week. There was a reduced low water-temperature stress response in the BPC-injected fish, as evidenced by the cortisol and glucose levels of the control and BPC groups. Lower levels were also observed in the BPC group than the control group during the second week. Cortisol levels were significantly lower in the BPC group than the control group. Histological examinations were conducted in the first and second weeks after the intramuscular injection of the recommended BPC dose to confirm the safety of BPC in aquaculture. There were no abnormalities observed in any tissue samples. This study confirms that the injection of BPC is safe even when used in a culture situation. BPC helps relieve stress and improves non-specific immune responses (innate immunity) in the olive flounder.

• Analytical Science and Technology
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• v.23 no.5
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• pp.477-484
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• 2010

Personal care products are a diverse group of synthetic organic chemicals such as antimicrobial compounds, UV filters and organo-phosphate flame retardants and derived from individual usages of soaps, toothpaste and cosmetics. It has been detected in municipal sewage effluent and various environmental samples such as surface water, marine, soil, sediment and aquatic biota in many countries. The occurrence of personal care products in environmental samples could negatively impact the health of the ecosystem and humans, due to persistent, long-term chronic exposure of aquatic organisms. In this study, fifteen personal care products in aquatic environmental samples were determined by gas chromatography-mass spectrometry (GC-MS) with liquidliquid extraction (LLE). Method detection limits were in the range of $0.004\sim0.273\;{\mu}g/L$. Two compounds (TCEP, TCPP) were detected in surface waters and seven compounds (triclosan, 4-MBC, EHMC, BP-3, TCEP, TPP, TBEP) were detected in sewage treatment plants (STP) influents or effluents.

• Korean Journal of Human Ecology
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• v.15 no.2
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• pp.327-339
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• 2006

We have investigated the distribution of major local foods cultivated in Gwangju City and Jeollanam-Do in order to understand the food culture of Honam region. The local foods were divided into 4 classes: agricultural, aquatic, animal and other products. 124 species of local foods, including 51 agricultural products, 50 aquatic products, 6 animal products and 17 others, were identified from this region. In Jeollanam-Do area, the agricultural products have a variety of fruits and vegetables, and aquatic products have fishes. In particular, rice, cucumber, pear, anchovy, oyster, laver, oyster mushroom, shiitake mushroom, and honey were determined as major local foods in Jeollanam-Do area. Note that Mudeungsan watermelon is cultivated in Gwangju, and sweet smelt and cat fish caught only in Sumjin river and Tamjin river area. In recent years, pumpkin (Cucurbita maxima Duchesne), paprika, kiwi and melon were determined as major local foods in Jeollanam-Do. Furthermore, branding strategy of agricultural and animal products can be said to improve. Wild types of aquatic productions, mushrooms and wild edible greens have been decreasing, whereas cultivated production increasing. The kinds of special local foods in Gwangju City and Jeollanamdo area were influenced by geographical, religious and social factors.

• Journal of fish pathology
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• v.36 no.2
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• pp.323-336
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• 2023

This study was conducted to find out the effect of yeast by-products discarded after beer production as feed additives for carp (Cyprinus carpio). After producing feed by adding high-temperature dried beer yeast by-products (HD), freeze-dried beer yeast by-products (FD), and freeze-dried fermented beer yeast by-products (FF) after lactobacilli fermentation, innate immunity indicators, survival rates, and challenge experiments were evaluated. Both ACH50 and lysozyme activity were significantly increased (p<0.05) in the experimental group of FF 0.2% and 0.5% compared to the control group from day 7 to day 21. In addition, phagocyte activity was significantly increased (p<0.05) in the group of FF 0.5% compared to the control group at all time points. Both IL-1β and TNF-α expression levels increased significantly in the FD and FF groups on day 21 compared to the control group (p<0.05). In addition, the FF 0.5% group showed significantly higher expression levels (p<0.05) at all time points. Similarly, IL-10 expression increased significantly (p<0.05) in FF 0.2% and 0.5% groups at all time points. SOD gene expression was significantly increased in FD 0.5% and all FF groups on day 14 and 21 (p<0.05). The results of a 10-day challenge experiment using Edwardsiella piscicida (E. piscicida) showed a higher relative survival rate than the control group at all concentrations that fed FD and FF. In summary, it is estimated that 0.5% FF can effectively improve the innate immunity, growth rate, and antibacterial properties of carp rather than using discarded beer yeast supernatant alone as a functional feed additive.

• The Journal of Bigdata
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• v.8 no.1
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• pp.157-165
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• 2023

Seafood is a major source of protein in many countries and its consumption is increasing. In Korea, consumption of seafood is increasing, but self-sufficiency rate is decreasing, and the importance of safety management is increasing as the amount of imported seafood increases. There are hundreds of species of aquatic products imported into Korea from over 110 countries, and there is a limit to relying only on the experience of inspectors for safety management of imported aquatic products. Based on the data, a model that can predict the customs inspection results of imported aquatic products is developed, and a machine learning classification model that determines the non-conformity of aquatic products when an import declaration is submitted is created. As a result of customs inspection of imported marine products, the nonconformity rate is less than 1%, which is very low imbalanced data. Therefore, a sampling method that can complement these characteristics was comparatively studied, and a preprocessing method that can interpret the classification result was applied. Among various machine learning-based classification models, Random Forest and XGBoost showed good performance. The model that predicts both compliance and non-conformance well as a result of the clearance inspection is the basic random forest model to which ADASYN and one-hot encoding are applied, and has an accuracy of 99.88%, precision of 99.87%, recall of 99.89%, and AUC of 99.88%. XGBoost is the most stable model with all indicators exceeding 90% regardless of oversampling and encoding type.

• The Journal of Fisheries Business Administration
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• v.27 no.1
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• pp.67-90
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• 1996

As an important factor of capitalism economics, price of commodities represents a certain country's economic index. For having correct price policy, there should be an appropriate mechanism to make and use systematic statistical data on price. Price statistics are made by indexes and price indexes are categorized into producer price index(PPI) and consumer price index(CPI). The Bank of Korea is publishing producer price index every year, but the producer price index contains some problems. These include as follows : (a) the impractical selection of fisheries products sample (b) uncorrect measure of aquatic products weights (c) investigating sample places. This study try to substitute producer price index of aquatic products and change construction of fisheries producer price index with experimental research on representative fisheries, weight of each fisheries, and suitability of investigating sample places. It is possible to improve practical fisheries producer price index with the results of this research. The findings are as follow. (a) It will be helpful for the government to make the fisheries price policy. (b) It can be used to understand trends of accurate price and price increase of aquatic products, and it's possible to compare with it other industrial indexes including the mining, agricultural, and manufacturing industry and understand relative price movement. (c) When free sales systems of fisheries products as expected, it will be helpful to analyze price movement of producing fisheries cooperatives, producing fisheries market and consuming fisheries market, analysis of market, and formation and consideration of budget. (d) It can be an important index to determine labor wage.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.6
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• pp.839-846
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• 1994

Changing concepts in fishery science increasingly are recognizing depletion of traditional stocks, utilization of alternate(non-traditional) species, demand for high quality products, and a total resource utilization approach. Innovative practices are occurring in fisheries processing wherein solid and liquid discharges are no longer treated as 'waste,' but rather as valuable feedstocks for recovery of a variety of value-added ('value enhanced') by-products. Among these are protein hydrolysates, soluble proteins and amino acids, proteolytic enzymes, flavor and flavor extracts, pigments, and biopolymers such as chitosan. Properties and applications of this deacetylated derivative of chitin are noted. Crustacean processing by-products are discussed in terms of their serving as materials for generation of natural flavors and flavor extracts, and products such as fish sauces using contemporary enzymatic techniques. Various food and feed applications of fisheries processing by-products are illustrated with increased usage seen in formulated diets for an expanding aquaculture market. Examples are given of aquaculture becoming increasingly significant in global fisheries resource projections. Critical issues in the international seafood industry Include those of seafood quality, processing quality assurance (HACCP), and recognition of the nutritional and health-related properties of fisheries products. A variety of current seafood processing research is discussed, including that of alternate fish species for surimi manufacture and formulation of value-added seafood products from crawfish and blue crab processing operations. Increasing emphasis is being placed on international aspects of global fisheries and the role of aquaculture in such considerations. Coupled with the need for the aquatic food industry to develop innovative seafood products for the 21st century is that of total resource utilization. Contemporary approaches in seafood processing recognize the need to discard the traditional concept of processing 'waste' and adapt a more realistic, and economically sound, approach of usable by-products for food and feed application. For example, in a period of declining natural fishery resources it is no longer feasible to discard fish frames following fillet removal when a significant amount of residual valuable flesh is present that can be readily recovered and properly utilized in a variety of mince-based formulated seafood products.

• Journal of fish pathology
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• v.35 no.2
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• pp.167-176
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• 2022

We injected infectious myonecrosis virus (IMNV) to pacific whiteleg shrimp, Litopenaeus vannamei, and observed closely with using light microscope and transmission electron microscope (TEM) for 4-8 days post infection (dpi). As clinical signs, abdominal bodies had mild opaque muscles at 5 dpi. And the mortality was shown at 6 dpi. At 8 dpi, most injected shrimps had severe opaque muscles and humped back that cause of movement disorder. As results of histopathological examinations, local parts of abdominal body muscle had muscle fiber hyalinization, muscle fiber atrophy, rounded muscle fibers, myofibrillar hypertrophy in size, a decrease in number of myofibrils and phagocytosis from the sarcolemmas by multiple hemocytes at 4 dpi. Especially, myofibrillar hypertrophy appeared at the whole or random part of single muscle fiber not in specific locations like the center or edge of muscle fiber. At 6-7 dpi, multiple muscle necrosis, muscle fiber segmentation, myofibril lysis ap- peared and a few hemocytes were infiltrated at lesions. At 8 dpi, extensive muscle necrosis, multiple myofibril lysis and muscle fiber atrophy were shown, and very few hemocytes were infiltrated. In early stage of infection, local viral myositis with zenker's degeneration were shown. These lesions appeared multiply after the early stage. In late stage of infection, extensive coagulative muscle necrosis appeared with few of inflammatory response such as hemocytes infiltration. The lack of hemocytes infiltration response at the late stage might be disadvantage for Litopenaeus vannamei to defense against IMNV and to recover, because hematocytes (granulocyte, semi-granulocyte) eliminate pathogen and damaged tissues from infection sites and help recover. As results of the TEM observation, IMNVs that had nonenveloped icosahedral capsid which was 30-40 nm diameter were in myofibril and beside tubules of sarcoplasmic reticulum and moved to the certain direction. The micro-tears and micro-trau- mas in myofibrils caused muscle fiber necrosis. And semi-granulocytes engulfed IMNVs to eliminate virus.