• Journal of fish pathology
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• 제28권2호
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• pp.113-116
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• 2015

A $0.45-{\mu}m$ membrane filter is generally used to remove bacterial contamination during virus extraction from fish samples. However, the number of fish viruses is drastically reduced after filtration with a $0.45{\mu}m$ filter. In this study, we investigated the effect of filters on virus infectivity titer and the change in virus titer and bacterial number following different centrifugation conditions to determine a suitable procedure for virus extraction from fish samples. $10^{4.05}$ and $10^{5.05}TCID_{50}/ml$ of infectious hematopoietic necrosis virus (IHNV) and $10^{4.05}$ and $10^{4.55}TCID_{50}/ml$ of Oncorhynchus masou virus (OMV) were not detectable after filtration with two types of $0.45-{\mu}m$ filters, except the IHNV titer was reduced by about 10 fold after filter use (company A). No significant difference was found in the virus titer following centrifugation at $880{\times}g$ (30 min) or $3,500{\times}g$ (30 min), whereas IHNV and OMV titers were reduced by about 10 and 10-1000 fold by centrifugation at $14,000{\times}g$ (30 min) and $14,000{\times}g$ (10 and 30 min), respectively. A total of 97.7-99.9% Escherichia coli were eliminated by centrifugation at $880 {\times}g$ (30 min) and $3,500{\times}g$ (30 min). These results show that fish viruses were affected by filtering, even though the effect differed by virus species and filter type. Therefore, centrifugation at $3,500{\times}g$ (30 min) and use of medium with antibiotics may be useful for virus extraction along with a reduction in bacteria.

• Korean Journal of Fisheries and Aquatic Sciences
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• 제39권2호
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• pp.78-84
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• 2006

A high performance liquid chromatography assay method for spiramycin in fish muscle was developed. The developed method was evaluated and validated by monitoring spiramycin in olive flounder (Paralichthys olivaceus), black rock fish (Sebastes schlegeli) and in live conger eel (Anguilla japonica) in fish farms and distribution centers. Using the developed method, the recovery rate was up to 82.4-88.8%, which was higher than that of conventional methods (77.6-87.1%). In particular, the proposed sample treatment protocol was suitable for use with fish samples to remove low molecular weight materials and pigments that could interfere an accurate analysis. The prepared stock solution was very stable, and it remained chemically stable for 5 weeks at $4^{\circ}C$. The performance limit of the developed method for spiramycin acid in fish muscle was 0.05 ppm. One hundred thirty-four fish samples including olive flounder, black rock fish and live conger eel were analyzed to evaluate the overall efficiency of the modified method and to monitor the actual condition of spiramycin usage in fish farms. Olive flounder and black rock fish were collected from fish farms in coastal areas of Korea, and live conger eels were purchased from a fish market in the Busan area from September 2001 to March 2002. According to the overall performance of the developed method, it was considered suitable for the monitoring of spiramycin in fish muscle. The suggested method of analysis for spiramycin in fish muscle is registered in the Korean Official Methods of Food Analysis and is currently tieing utilized for fishery products inspection by the Korea Food and Drug Administration and the National Fisheries Products Quality Inspection Service.

• Fisheries and Aquatic Sciences
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• 제1권1호
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• pp.129-146
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• 1998

Fatty acid compositions of seventy-two species of Korean fish muscle, 59 species of sea water fish and 13 species of fresh water fish, were studied. Polyunsaturated fatty acid (PUFA) was the richest fatty acid group in all fish samples, accounting for $38.0\pm10.3\%$ of total fatty acids. Monounsaturated fatty acids $(MUFA,\;31.4\pm9.67\%)$ and saturated fatty acids $(SFA, 30.5\pm3.81\%)$ showed a similar level. There was a positive correlation between the total lipid content and MUFA (r=0.7788, p<0.001) and a negative correlation between the total lipid content and PUFA (r= -0.7786, p<0.001) while there was no correlation between the total lipid content and SFA. The proportion of n-3 PUFA and n-6 PUFA was $29.7\pm8.73\%$ and $6,48\pm3.70\%$, respectively, in all fish samples. The n-3 PUFA was rich in sea water fish while n-6 PUFA was rich in fresh water fish. The migratory fish contained the highest level of the n-3 PUFA $(1.82\pm1.01g/100g\;muscle)$, followed by the fresh water fish $(1.09\pm1.04g/100g\;muscle)$, the reef fish $(0.90\pm0.60g/100g\;muscle)$ and the demersal fish $(0.77\pm0.38g/100g\;muscle)$. There was a positive correlation between the total lipid and n-3 PUFA content, $y=0.2083\times+0.05 (r=0.9352,\;p<0.0010)$.

• Journal of the Korean Society of Food Science and Nutrition
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• 제45권8호
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• pp.1192-1201
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• 2016

This study was conducted to investigate sensory characteristics and consumer acceptance of sliced raw fish. The two most popular varieties in Korea, flounder and rockfish, were used. Samples of each variety were prepared as follows to create consistent perceptible sensory differences: 'fresh' (consumed within 2 h after sacrifice), 'aged' (stored at $1^{\circ}C$ for 24 h), 'frozen' (frozen at $-16^{\circ}C$ for 23 h then thawed at $23.5^{\circ}C$for 1 h), and 'immersed' (immersed in sterilized water at $1^{\circ}C$ for 24 h). Sensory profiles of samples were determined through quantitative descriptive analysis using 10 trained panelists. Consumer acceptance test was conducted using 47 consumers. Analyses of variance were conducted to test significance of differences in sensory profiles and hedonic ratings among samples. Consumers were clustered according to their overall liking scores, and their preference patterns were cross-checked with sensory profiles. For both fish varieties, 'fresh' was characterized by stronger hardness, cohesiveness, springiness, cartilage-like texture (applied to only rockfish), and fishy flavor, whereas 'frozen' and 'immersed' were distinguished from other samples for their stronger wetness, juiciness, and fresh fish flavor than those of other samples. 'Aged' was significantly less hard, cohesive, and springy than 'fresh' as well as less juicy and wet than 'frozen' and 'immersed'. Consumers significantly preferred 'fresh' flounder and rockfish to others for their strong cohesiveness and springiness, indicating textural attributes were main factors affecting consumer preferences. However, for both flounder and rockfish, 40~50% of respondents preferred 'frozen' and 'immersed' to 'fresh' for their tenderness and fresh fish flavor. For this group of consumers, flavor liking had a greater effect on overall preference than texture preference. The result suggests that cohesive and springy textures and fresh fish flavor are major drivers of preferences for raw fish slices, but their relative importance and optimal levels varied across individual consumers.

• Journal of Food Hygiene and Safety
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• 제16권3호
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• pp.241-246
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• 2001

Distribution of pathogenic vibrios in the seawater of live fish tank and effect of environmental factors on their existence were investigated by collecting samples from fish markets and restaurants in 6 different cities. Pathogenic vibrios and coliforms were determined by using the most probable number (MPN) procedure, and aerobic plate count was enumerated by the standard pour plate method. No Vibrio chulerae O1 was detected in all the samples tested. Detection rates of V. cholerae non-O1, V. parahaemolyticus and V. vulnificus in all the smaples tested were 7.7%, 69.2% and 23.1%, respectively. Water temperature and trubidity of the seawater measured were higher in the pathogenic vibrios positive samples than in those negative samples. However, higher salinity and pH were shown in the pathogenic vibrios negative samples than in positive samples. The aerobic plate counts and MPN or total and focal coliforms in the seawater were higher in the presence of pathogenic vibrios than in the absence of pathogenic vibrios. In this study, the presence of pathogenic vibrios in the seawater tested was closely related with other physiochemical parameters and populations of coliforms, indicators far food safety.

• Food Science of Animal Resources
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• 제40권5호
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• pp.675-688
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• 2020

Polycyclic aromatic hydrocarbons (PAHs) are dangerous chemical compounds that can be formed by cooking foods at high temperatures. The aim of this study is to determine the level of contamination of PAH compounds with high performance liquid chromatography (HPLC) on heat treated meat samples and the consumption of PAH compounds in meat samples, as well as the dietary exposure status and possible health risk estimation. In five different heat treated meat samples (meat doner, chicken doner, meatballs, grilled chicken, and fish), the total PAH (Σ16PAH) contamination level was 6.08, 4.42, 4.45, 4.91, and 7.26 ㎍/kg, respectively. Benzo[a]pyrene (BaP) in meatballs and grilled fish samples had a level 0.70 and 0.73 ㎍/kg. All of the samples analyzed were found to be below the EU permitted limit (5 ㎍/kg) in terms of BaP. Estimates of daily intake (EDI) for a total of 16PAH in heat treated meat doner, chicken doner, meatballs, grilled chicken and fish samples were 3.41, 3.71, 2.49, 4.12, and 1.77 ng/kg bw/day, respectively. In this study, the average margin of exposure (MOE) value calculated was found in the range of 179.487 and 425.000 for BaP and PAH4. This study is the first study to provide important information in terms of evaluating the possible health risk that PAH compounds can create in people's diets due to heat treatment of meat and meat products in Sivas, Turkey.

• 한국해양학회지
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• 제4권1호
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• pp.17-35
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• 1969

This work concerns morphological studies of the Japaness jack mackerel, Trachurus japonicus(Temminck & Schlegel). A total of 48 random samples consisting of 2669 fish is examined, representing three geographic regions, namely, Kamakura, Nagasaki, and Tottori. Preservation affects length and weight of fish considerably, but the variability after 10 days is shown to be negligible. The variability in measuring the morphometric characters due to different measures and orders is found to be significant. They are relatively small, however, compared to the variability in mean length to be expected in samples drawn from the population. Two meristic characters, namely, anal and second dorsal fin rays and three morphometric characters, namely, head length, first and second dorsal insertion distances are chosen for the study. Results of the statistical analysis reveal that differences in the selected meristic characters among samples within and between regions are found to be significant. In general, it is reasonable to state that the jack mackerel collected in Nagasaki region, on the average, have greatest number of anal fin ray and second dorsal fin ray followed by Kamakura, and Tottori regions in that order. It is found that although no significant differences in the slope of regression line are noticed, the mean differences of the selected morphometric measurements in relation to fish length are found to be significant among samples within each region. Differences in the regression coefficients as well as the adjusted sample means are found to be significant between regions. The analysis suggests that samples from Nagasaki region, on the average, have longest head length and greatest distances from snout to the insertion of first dorsal and second dorsal fins followed by Kamakura, and Tottori regions in that order.

• Korean Journal of Fisheries and Aquatic Sciences
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• 제56권2호
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• pp.253-258
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• 2023

This study was conducted to inhibit histamine formation in salt-fermented anchovy Engraulis japonicus fish sauce, by lowering the pH using 1% citric acid as food additive during the initial fermentation stage. The fish sauce samples were prepared with fresh anchovies used immediately after being caught (F), and left at ambient temperature for 4 h, and 24 h with 25% salt, 1% citric acid, and without citric acid for a 6-month fermentation period. The content of ammonia nitrogen, total nitrogen, and glutamic acid in fish sauce was unaffected by the addition of citric acid during the fermentation period. The histamine content of F and 4 h samples were 20.5-30.6 and 77.4-119.3 mg/kg, respectively. The histamine content of F and 4 h samples with 1% citric acid was 4.1-8.7 and 50.4-56.1 mg/kg, respectively. Furthermore, addition of citric acid did not inhibit histamine formation in 24 h sample that had lower freshness quality. Additionally, effective inhibition of histamine is observed during manufacturing of salt-fermented anchovy fish sauce on an industrial scale, suggesting that lowering the initial pH using 1% citric acid does not alter the taste and flavor of the fish sauce.

• Journal of fish pathology
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• 제22권1호
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• pp.75-83
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• 2009

Disease surveillance was performed to monitor the prevalence of fish pathogens in wild marine fish caught in coastal offshore water from February to October in 2008. A total of 401 fish samples were collected at set net or fish market at landing port on the coast of Pohang, Geoje, Yeosu and Jeju. In this study, 17 kinds of fish pathogens were isolated from 152 fish samples. The detection rates of parasites, bacteria or viruses were 21.4%, 17.0% and 2.7%, respectively. The detected parasites were Scutica, Trichodina, Cryptocaryon, Dactylogyrus, Microcotyle, Benedenia, Bivagina, Heteraxin, Caligus, Epistylis and nematode. The dominant bacterial pathogens were Vibrio, Streptococcus, Photobacterium and Psuedomonas. Red sea bream iridovirus (RSIV) and lymphocystis disease virus (LDV) were detected in 6 species of fish virus examined in this study. The detection rates of fish pathogens from Scorpaenidae, Monacanthidae, Pleuronectidae, Sparidae and Carangidae investigated over 30 samples were 59.2%, 48.4%, 34.2%, 30.6% and18.2%, respectively.

• Asian Pacific Journal of Cancer Prevention
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• 제16권17호
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• pp.7997-8002
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• 2015

Gene amplification is an important mechanism in the development and progression of cancer. Currently, gene amplification status is generally determined by in situ hybridization (ISH). Multiplex ligation-dependent probe amplification (MLPA) is a PCR-based method that allows copy number detection of up to 50 nucleic acid sequences in one reaction. The aim of the present study was to compare results for HER2, CCND1, MYC and ESR1 gene amplification detected by MLPA with fluorescent in situ hybridization (FISH) and chromogenic in situ hybridization (CISH) as clinically approved methods. Tissue samples of 170 invasive breast cancers were collected. All were ER positive. Tissue samples had previously been tested for HER2 using immunohistochemistry. Amplification of the selected genes were assessed using MLPA, FISH and CISH and results were compared. HER2 MLPA and ISH results were also compared with HER2 immunohistochemistry (IHC) which detects protein overexpression. Amplification of HER2, CCND1, MYC and ESR1 by MLPA were found in 9%, 19%, 20% and 2% of samples, respectively. Amplification of HER2, CCND1, MYC and ESR1 by FISH was noted in 7%, 16%, 16% and 1% of samples, respectively. A high level of concordance was found between MLPA/FISH (HER2: 88%, CCND1: 88%, MYC: 86%, ESR1: 92%) and MLPA/CISH (HER2: 84%). Of all IHC 3+ cases, 91% were amplified by MLPA. In IHC 2+ group, 31% were MLPA amplified. In IHC 1+ group, 2% were MLPA amplified. None of the IHC 0 cases were amplified by MLPA. Our results indicate that there is a good correlation between MLPA, IHC and ISH results. Therefore, MLPA can serve as an alternative to ISH for detection of gene amplification.