• Journal of Microbiology and Biotechnology
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• v.31 no.5
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• pp.756-763
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• 2021

Agarose is a linear polysaccharide composed of ᴅ-galactose and 3,6-anhydro-ʟ-galactose (AHG). It is a major component of the red algal cell wall and is gaining attention as an abundant marine biomass. However, the inability to ferment AHG is considered an obstacle in the large-scale use of agarose and could be addressed by understanding AHG catabolism in agarolytic microorganisms. Since AHG catabolism was uniquely confirmed in Vibrio sp. EJY3, a gram-negative marine bacterial species, we investigated AHG metabolism in Streptomyces coelicolor A3(2), an agarolytic gram-positive soil bacterium. Based on genomic data, the SCO3486 protein (492 amino acids) and the SCO3480 protein (361 amino acids) of S. coelicolor A3(2) showed identity with H2IFE7.1 (40% identity) encoding AHG dehydrogenase and H2IFX0.1 (42% identity) encoding 3,6-anhydro-ʟ-galactonate cycloisomerase, respectively, which are involved in the initial catabolism of AHG in Vibrio sp. EJY3. Thin layer chromatography and mass spectrometry of the bioconversion products catalyzed by recombinant SCO3486 and SCO3480 proteins, revealed that SCO3486 is an AHG dehydrogenase that oxidizes AHG to 3,6-anhydro-ʟ-galactonate, and SCO3480 is a 3,6-anhydro-ʟ-galactonate cycloisomerase that converts 3,6-anhydro-ʟ-galactonate to 2-keto-3-deoxygalactonate. SCO3486 showed maximum activity at pH 6.0 at 50℃, increased activity in the presence of iron ions, and activity against various aldehyde substrates, which is quite distinct from AHG-specific H2IFE7.1 in Vibrio sp. EJY3. Therefore, the catabolic pathway of AHG seems to be similar in most agar-degrading microorganisms, but the enzymes involved appear to be very diverse.

• Fisheries and Aquatic Sciences
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• v.19 no.3
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• pp.14.1-14.10
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• 2016

Isoelectric solubilization/precipitation (ISP) processing allows selective, pH-induced water solubility of proteins with concurrent separation of lipids and removal of materials not intended for human consumption such as bone, scales, skin, etc. Recovered proteins retain functional properties and nutritional value. Four roe protein isolates (RPIs) from yellowfin tuna roe were prepared under different solubilization and precipitation condition (pH 11/4.5, pH 11/5.5, pH 12/4.5 and pH 12/5.5). RPIs contained 2.3-5.0 % moisture, 79.1-87.8 % protein, 5.6-7. 4 % lipid and 3.0-3.8 % ash. Protein content of RPI-1 and RPI-2 precipitated at pH 4.5 and 5.5 after alkaline solubilization at pH 11, was higher than those of RPI-3 and RPI-4 after alkaline solubilization at pH 12 (P < 0.05). Lipid content (5.6-7.4 %) of RPIs was lower than that of freeze-dried concentrate (10.6 %). And leucine and lysine of RPIs were the most abundant amino acids (8.8-9.4 and 8.5-8.9 g/100 g protein, respectively). S, Na, P, K as minerals were the major elements in RPIs. SDS-PAGE of RPIs showed bands at 100, 45, 25 and 15 K. Moisture and protein contents of process water as a 2'nd byproduct were 98.9-99.0 and 1.3-1.8 %, respectively. Therefore, yellowfin tuna roe isolate could be a promising source of valuable nutrients for human food and animal feeds.

• Journal of Veterinary Clinics
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• v.23 no.2
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• pp.164-168
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• 2006

The residue depletion of ampicillin was investigated in the olive flounder (Paralichthys olivaceus), rockfish (Sebastes schlegeli), and red sea bream (Pagrus major) after 5 days treatment with medicated feed at a dose of 100 mg/kg bw/day. Fishes were sampled for muscle on 1st, 2nd, 3rd, and 4th day after treatment. Ampicillin concentrations were determined by high performance liquid chromatography after SPE column extraction. The recovery rates of ampicillin in muscle samples ranged 94-98% and 83-88% for the concentration of 0.05 mg/kg and 0.1 mg/kg, respectively. Ampicillin concentrations detected on 1st day after treatment were 0.143, 0.138, and 0.187 mg/kg in the muscle of olive flounder, rockfish, and red sea bream, respectively. After a withdrawal of 3 days, muscle concentrations were 0.016, 0.012, and 0.021 mg/kg in the olive flounder, rockfish, and red sea bream, respectively. Ampicillin was not detectable in muscle samples on 4 days following withdrawal of the medicated feed. From results of the present study, a withdrawal period of ampicillin is proposed on 5 days after 5 days treatment with medicated feed at a dose of 100 mg/kg bw/day to avoid the presence of excessive residues of the edible muscles of olive flounder, rockfish, and red sea bream.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.6
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• pp.591-599
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• 2009

Genetic parameters for growth-related traits were estimated in 9-month old of two Korean abalone subspecies, Haliotis discus hannai and H. discus discus, using multiple traits of animal model. The data were collected from the records of 3,504 individuals produced from 16 sires and 17 dams in H. discus hannai and 821 individuals produced from 3 sires and 4 dams in H. discus discus, which was evaluated at the Bukjeju branch, NFRDI, from May 20, 2004 to February 14, 2005. The heritability estimates obtained from restricted maximum likelihood (REML) method range from 0.29 to 0.31 for three growth traits (shell length, shell width and body weight) in H. discus hannai and from 0.22 to 0.28 in H. discus discus, respectively. The heritabilities for shell shape and condition factor were lower than others of growth traits such as ranging from 0.03 to 0.24 in H. discus hannai and from 0.06 to 0.11 in H. discus discus, respectively. Genetic and phenotypic correlations were >0.91 between shell parameters and weight in two abalone subspecies, respectively, indicating that breeding for weight gains could be successfully achieved by selecting for shell length.

• Food Science of Animal Resources
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• v.25 no.3
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• pp.344-349
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• 2005

Two different NokJoongTangs were prepared by boiling antler and various oriental medicinal materials. The phenolic contents and free radical scavenging effects against DPPH(1,1-diphenyl-2-picrylhydrazyl) radical and hydroxyl radical of the NokJoongTangs which are used as the health supplement foods, were investigated. NokJoongTang-II prepared dried antler with various oriental medicinal materials, had higher phenolic content than that of NokJoongTang-I prepared 1mm raw antler with the same materials. In addition, NokJoongTang-II exhibited higher scavenging activities than these of NokJoongTang-I against DPPH radical and hydroxyl radical. These result indicate that free radical scavenging activity of NokJoongTang showed a difference by using raw and dry antler for NokJoongTang preparation, and that the findings also show a positive correlation between radical scavenging activity and total phenolic contents.

• Fisheries and Aquatic Sciences
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• v.25 no.11
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• pp.537-548
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• 2022

Apparent digestibility coefficients (ADCs) of dry matter, crude protein, crude lipid, nitrogen-free extract, energy and essential amino acids in animal-based feed ingredients were determined for olive flounder (Paralichthys olivaceus). A reference diet (RF) was formulated to contain 1.0% chromic oxide (Cr₂O₃) as an inert indicator. Nine test diets were formulated to contain RF and one of the feed ingredients (pollock meal [PM], jack mackerel meal [JMM], anchovy meal [AM], cod meal [CM], sardine meal [SM], sand eel meal [SEM], tuna meal [TM], meat meal [MM] and squid liver meal [SLM]) at a 7:3 ratio in each diet designated as PM, JMM, AM, CM, SM, SEM, TM, MM and SLM, respectively. Olive flounder, averaging 150 ± 8.0 g, were stocked at a density of 25 fish per tank in 400-L fiberglass tanks attached with fecal collection columns. Feces were collected from triplicate groups of fish one time a day for four weeks. Dry matter and crude protein ADCs of CM and SEM were significantly higher than the other tested ingredients. Lipid ADCs of JMM, CM and SEM were significantly higher than the other test ingredients. Energy ADCs of CM and SEM were significantly higher than that of the other tested ingredients. The availability of amino acids in CM was generally higher than the other animal protein sources. PM exhibited the lowest amino acid availability among the treatments. Interestingly, MM exhibited significantly higher nutrient digestibility than several marine-based ingredients. However, CM and SEM are seeming to be highly digestible and effective to use in olive flounder diet compared to the other tested ingredients. Overall, the results of this study provide information about the bioavailability of nutrients and energy in animal feedstuffs to apply when formulating cost-effective practical feeds for olive flounder.

• Journal of Animal Science and Technology
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• v.52 no.4
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• pp.337-346
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• 2010

We report non-specific immune responses and disease resistance against Vibrio anguillarum, Streptococcus iniae and Edwardsiella tarda by dietary supplementation of fermented garlic powder (FGP) in olive flounder for the first time. Four isonitrogenous (45% crude protein) and isocaloric (17.1 MJ/kg) diets were formulated to have 0%, 0.5%, 1% and 2% of the FGP (G-0, G-0.5, G-1 and G-2). The experimental diets were fed to juvenile olive flounder averaging 23.4 g in triplicate groups (90 fish/group) in a flow-through system. After a five-week feeding trial, healthy fish with similar sizes from each tank were selected and injected with 1 ml of three bacteria each to evaluate disease resistance of the fish. During the 5-week feeding trial, the weight gain, specific growth rate, feed conversion ratio, protein efficiency ratio, and survival of the fish were not significantly affected by the experimental diets. However, feed intake was significantly lower (P<0.05) in the fish fed the G-2 diet compared with the control group. Hemoglobin, myeloperoxidase activity, cholesterol and HDL-cholesterol were not different between the dietary groups. However, hematocrit, nitroblue tetrazolium (NBT) activity, and lysozyme activity were increased (P<0.05) with an increment of dietary FGP. Plasma triglyceride of the fish fed the G-0.5 diet was significantly lower than that of fish fed the control diet. The cumulative mortality was lower in the fish fed diets containing FGP compared with the control group in the challenge test except for the bacteria Edwardsiella tarda. The results in this study indicate that dietary supplementation of FGP can enhance the non-specific immune responses and disease resistance of olive flounder against V. anguillarum and S. iniae.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.5
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• pp.636-642
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• 2011

The effect of different rates of ethanol additive on fermentation quality of napiergrass (Pennisetum purpureum) and residual water soluble carbohydrate were studied in the experiment. The addition rate of ethanol was 0%, 1.5%, 2.5%, 3.5%, 4.5% on fresh weight of napiergrass. The laboratory silos were kept in the room, then were opened on 1, 3, 5, 7, 14, 30 days after ensiling and the changes of silage quality were analyzed, respectively. There was a fast and large reduction in pH from the 5th day of ensiling to below 4.2 except for the 4.5% treatment. After five days the pH of silage decreased slowly and the pH of the ethanol additions was lower than the control. Lactic acid content of ethanol treatments increased significantly (p<0.05) from the 5th day of ensiling, reaching the highest value on either the 7th day or 14th day. The ethanol additive inhibited the break down of silage protein and the ammonia nitrogen content of ethanol addition silage was significantly (p<0.05) lower than the control after 30 days of ensiling. Within the initial first day of ensiling the water soluble carbohydrate content declined quickly. The efficiency of water soluble carbohydrate usage was higher in silage with ethanol than in the control. The acetic acid of ethanol treatment was significantly (p<0.05) lower than control on first and 14th day, but there was no significant (p>0.05) difference among the ethanol addition silages. The volatile fatty acids content of silage increased gradually from the first day of ensiling and reached the peak on 14th day or 30th day and the content of ethanol addition treatment was significantly (p<0.05) lower than the control. The experimental results indicated that adding ethanol inhibited the use of protein and water soluble carbohydrate of aerobic bacteria and reduced the silage losses during the early stage of ensiling and thus supplied more fermentation substrate for lactic acid bacteria and improved the fermentation quality of napiergrass.

• Food Science of Animal Resources
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• v.28 no.4
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• pp.395-400
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• 2008

This study was carried out to compare the textural properties of crab-flavored sausage manufactured with six different formulations. We prepared crab-flavored sausage from Alaska pollack surimi as a control by the washing method, and various mixtures of surimi and chicken breast meat were manufactured (pH 11.0) with 33.33% chicken breast meat (CBM) (T1), 50% CBM (T2), 66.66% CBM (T3), 100% CBM (T4) and 20% commercial mechanically deboned chicken meat (MDCM) (T5). Brittleness, gumminess, chewiness, breaking force, gel strength, jelly strength, sensory flavor. texture, and overall acceptability were significantly lower in the formulations containing chicken meat in proportion to the % CBM (p<0.05). However, cohesiveness and springiness were significantly higher in the formulations containing chicken meat in proportion to the amount of CBM (p<0.05). Folding test and deformation values were significantly lower in the surimi manufactured with CBM at pH 11.0. although T5 showed no significant differences relative to the control. Overall, these results indicate that similar textural properties in the crab-flavored sausage were attained when surimi was prepared with 20% CBM and MDCM.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.1
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• pp.38-42
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• 2000

Thig study was conducted to get a knowledge on chemical components of the cooked tuna bones (skipjack tuna bone and yellowfin tuna bone) as a food resource. The crude protein of tuna bone was around $29{\%}$ on the dry basis. The imino acid content (193 imino acid residues /1,000 amino acid residues) of collagen extracted from yellowfin tuna bone was higher than that (173 imino acid residues /1,000 amino acid residues) of collagen extracted from skipjack tuna bone, however, it was lower than that of collagen extracted from animal bone. The content and the ratio of unsatuated fatty acids in lipid extracted from yellowfin tuna bone were higher than those of lipid extracted from skipjack tuna bone, but they were lower than those of squid viscera oil. The contents of calcium and phosphorus as the major components of the tuna tone were 36.5 g and 17.2 g in 100 g ash in the skipjack, respectively, and 38.0 g and 18.7 g in 100 g ash in the yellowfin, respectively. It was concluded from these results that tuna bones could be effectively utilized as a mineral source.