• Journal of Life Science
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• v.10 no.1
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• pp.24-27
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• 2000

For the rapid diagnosis of vibriosis in penaeid shirmp, the indirect fluorescent antibody technique(IFAT) was established to detect Vibrio alginolyticus. The titers of the antisera used for this experiment were above 1280. Vibrio alginolyticus possesses the specific antigen, and also have antigens shared with other strains. When an V. alginolyticus-infected adult shirmp was tested by IFAT, V. alginolyticus was detected mainly in the muscle tissues near the injection point and the haemolymph but only few in other tissues. This result indicates that the pathogen bacteria could be detected by IFAT. Thus, it is suggested IFAT is more convenient and sensitive method than conventional plate method for the diagnosis of induced Vibrio infection in the penaeid shrimps.

• Journal of the Korean Chemical Society
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• v.4 no.1
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• pp.85-87
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• 1957

We have studied on the effect of hydrochloric acid on the hydrolysis of dried cuttlefish, sardine, shrimp, sea mussel and undaria taking various concentration of acid, heating at various periods at constant temperatures and under atmospheric pressure following results were obtained. 1. The addition of HCl increases hydrolysis ratio of marine products rapidly, having maximum point of its ratio at 30% of dried cuttlefish and shrimp, at 25% of sea mussel and undaria, at 15% of sardine. 2. Hydrolysis ratios of cuttlefish and shirmp, sea mussel and undaria, and sardine reach maximum values at 30% of HCl, 25% of HCl and 15% of HCl, respectively.

• BMB Reports
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• v.37 no.6
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• pp.726-734
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• 2004

White spot disease (WSD) is caused by the white spot syndrome virus (WSSV), which results in devastating losses to the shrimp farming industry around the world. However, the mechanism of virus entry and spread into the shrimp cells is unknown. A binding assay in vitro demonstrated VP28-EGFP (envelope protein VP28 fused with enhanced green fluorescence protein) binding to shrimp cells. This provides direct evidence that VP28-EGFP can bind to shrimp cells at pH 6.0 within 0.5 h. However, the protein was observed to enter the cytoplasm 3 h post-adsorption. Meanwhile, the plaque inhibition test showed that the polyclonal antibody against VP28 (a major envelope protein of WSSV) could neutralize the WSSV and block an infection with the virus. The result of competition ELISA further confirmed that the envelope protein VP28 could compete with WSSV to bind to shrimp cells. Overall, VP28 of the WSSV can bind to shrimp cells as an attachment protein, and can help the virus enter the cytoplasm.

• Applied Biological Chemistry
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• v.34 no.3
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• pp.242-248
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• 1991

The sucrose, MSG, fresh oyster and salted-fermented anchovy and shirmp were added into Kimchi in the concentration range of $1{\sim}3%$ and studied for their effects on the changes in chemicl properties and fermentation rate. The control Kimchi was prepared with addition of 2% red pepper, garlic, Welsh onion and 1% ginger. It was found that the fermentation rate was increased as the concentration of all of ingradients tested increased. Among them M.S.G affected most significantly. However, ascorbic acid formed was reduced for those Kimchi added with salted-fermented anchovy and shrimp while the changes in pH and titrable acidity was affected a little.

• Preventive Nutrition and Food Science
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• v.3 no.3
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• pp.221-224
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• 1998

Toha-jeot, salt-fermented Toha shirmp(caridina denticulata denticulata DeHAAN) is a traditional fermented food in Korea. Samples of Toha-jeot used in the present study were a low-salt group of 15% sodium chloride(L), a high-salt group of 23% sodium chloride(H), a 50% conventional soybean sauce group(S), a low-salt group contraining 2% wheat bran (W2%-L) , a high -salt group containing 2% wheat bran(W2%-H), a low-salt group containing 4% wheat bran(W4%-L)and a high-salt group containing 4% wheat bran (W4%-H). These seven groups were refrigerated at 4 $\pm$1$^{\circ}C$ and then taken out for analysis at theree month intervals. We investigated the functional components of Toha-jeot during fermentation . Long fermentation of Toha-jeot lowered the viscosity of chitin and tended to reduce the distribution of molecular weight. THe formation of chitin oligosaccharides on the other hand, increased significantly. After nine months of fermenttion, chitin oligosaccharides(M.W. 823~1789) constituting 24.75% of Toha chitin were produced in the sample of W2%-H. During the same period, chitin oligosaccharides(M.W.1436-1879) constituting 66.30% of Toha chitin were produced in the samples of S. However, chitin oligosaccharides were not produced in Jeotsaeu-jeot made of sea-water shrimp when fermented for six months.

• Journal of Aquaculture
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• v.15 no.1
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• pp.7-13
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• 2002

Since 1993, the White Spot Syndrome Virus (WSSV) disease occurred in China among cultured shrimps resulting in mass mortality. Epizootiological surveys undertaken during the outbreak period of 1993-1994 indicated that all stages of Penaeus chinensis, P. japonicus and P. monodon were infected. Consequent to the transport of contaminated shrimp seedlings and seawater, the disease spread all over the farms of China. The disease was more rapidly transmitted at temperatures above $25^{\circ}C$. Challenge experiments showed the causative agent was highly virulent. White spots appeared on the carapace of both span-taneous and experimentally infected shrimps. Moribund shrimps contained turbid hemolymph, hypertrophied Iymphoid organ and a necrotic mid-gut gland. Electron microscopy showed the presence of viral particles in the gills, stomach, lymphoid organ, and epidermal tissue of the infected shrimp. The visions were slightly ovoid with an envelope and averaged 350 $\times$ 150 nm; nucleocapsids measured 375 $\times$ 157 nm. With discontinuous sucrose gradient of 35, 50 and 60% (w/v), the virus was separated from hemolymph of the infected shrimp. The estimated molecular weight of genomic DNA was 237 Kb with EcoR I, 247 Kb with Hind III and 241kb with Pst I. A total of 9 hybridoma colones secreting monoclonal antibodies (MAbs) were produced from mouse myeloma and spleen cells immunized with WSSV. The immunofluorescence assay of gill tissue showed that the MAbs reacted with diseased but not with healthy shrimp. The MAbs belonged to IgGl, IgG2b subclass and IgM class, all with kappa light Immune-electron-microscopy with colloidal gold marker showed the presence of 5 MAbs epitopes on the envelope and one on the capsid of the virus. Baculoviral mid-gut gland necrosis showed the specificity of the MAbs produced. For diagnosis 5 different methods were selected. Using Kimura primers for PCR, or MAbs for immunoblot, ELISA or FAT method, in situ hybridization was carried out to show the gene. All these methods detected WSSV in the organ samples of the diseased shrimp but not in healthy one.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.4
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• pp.629-634
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• 2000

The effects of gamma irradiation on changes of chemical compounds of fermented shromp with low salt were studied. The shirmp was salted NaCl concentration of 10%, 15% and 20%, and irradiated at 0, 2.5, 5.0, 7.5 and 10.0kGy. Amino nitrogen (AN), volatile basic nitrogen (VBN), trimethylamine (TMA) and neutral protease acivity were examined during ferentation at 15$^{\circ}C$. A sample with 30% salt concontration was also prepared as a control. The initial contents of AAN, VBN, TMA and protease acitivity were not affected by gamma irradiation. The contents of AN, VBN and TMA were incteased with fermentation period. But, the more increased NaCl concentrations and the higher irradiation dose, the loss increased content of chemical compounds and protease activity were found. Protease was increased until 4~5 weeks and then decreased gradually. The results showed that the chemical compounds and protease activity of salted abd fermeted shrimp prepared with 15% NaCl contentration and 10 kGy irradiation dose, or 20% and 5 kGy or higher were maintained the appropriate level of quality up to 10 weeks of storage compared with the control.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.5
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• pp.624-633
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• 2021

This study was conducted to determine the supplemental effects of two insect meals, mealworm (MW) and black soldier fly (BSF), with high or low lipid levels in diets, on Pacific white shrimp Litopenaeus vannamei. Sardine and tuna by-product meals were used as the fish meal source in a control (Con) diet. The fish meals were replaced with MW, defatted MW (deMW), BSF or defatted BSF (deBSF), respectively. The shrimp (body weight: 0.47 g) were stocked into 20 acryl tanks (215 L) and fed the diets six times a day. After 45 days of the feeding trial, the shrimp that were fed insect meals had significantly higher phenoloxidase and superoxide dismutase activities than the shrimp fed Con diet. The gene expressions of prophenoloxidase, crustin and penaeidine-3c in shrimp hepatopancrease were also higher in shrimp that were fed the insect diets, regardless of defatting than those in shirmp that were fed Con diet. The survival against Vibrio parahaemolyticus was higher in shrimp that were fed the diets containing defatted insect meals than in shrimp that were fed Con diet. These results indicate that MW and BSF, regardless of lipid levels, could be good protein sources for the enhancement of innate immunity and anti-oxidant capacity of the shrimp.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.57 no.4
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• pp.355-363
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• 2024

Although aquaculture shrimp production has increased, disease mortality has also increased. Acute hepatopancreatic necrosis disease (AHPND) is an emerging disease that significantly reduces production. In this study, we have investigated the potential of medicinal herbs in enhancing the immune system of shrimp. A mixture of medicinal herb extracts (Han In-jin, Artemisia iwayomogi kitamura and Cham Dang-gwi, Angelicae gigas Nakai) was absorbed into pellets and fed to whiteleg shrimp Litopenaeus vannamei for 12 weeks. The weight gain, immune activity, and disease resistance effects of the shirmp were examined. The growth performance of shrimp fed the mixture of medicinal herbal extracts was higher than that of the control group. The prophenoloxidase (proPO) activity was found to be significantly higher at 8 weeks in the 0.1% medicinal herb extract fed group. The cumulative mortality when artificially infected with AHPND pathogens commonly decreased in the 8 weeks fed group when compared with the control group. Furthermore, the RPS (relative percentage survival) was improved. This study confirmed that a mixture of medicinal herbal extracts has a positive effect on growth performance, innate immunity and disease resistance in shrimp. The optimum concentration of the medicinal herb extract for shrimp feed was 0.1% .

• Applied Biological Chemistry
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• v.32 no.3
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• pp.278-285
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• 1989

Effects of cooking and drying methods on the taste component and microstructure of shrimp, Metapenaeus joyneri, were investigated. The nucleotides and their related compounds of fresh shirmp such as ATP, ADP, AMP, IMP, inosine and hypoxanthine were detected. AMP was detected as a trace amount in fresh shrimp, however, it increased up to $23.5{\sim}45.7{\mu}$ moles with cooking and drying due to the decomposition of ATP and ADP to AMP during cooking and drying. The major component of the free amino acids of fresh shrimp was arginine followed by glycine, lysine, proline and alanine. These free amino acids contents were 70% of the total free amino acids. One hundred grams of fresh shrimp contained 1,198mg (dry basis) of the total free amino acids. However, for hot air and freeze dried cooked shrimps it was decreased down to 342mg (dry basis) and 503mg (dry basis), respectively. It might be due to the dissolution of soluble amino acids during cooking. Hot air-and freeze-dried fresh shrimps was higher in hardness and brittleness but lower in cohesiveness and gumminess than hot air-and freeze-dried ones with boiling and microwave heating. Freeze dried shrimp had softer myofibril texture than hot air dried one. At the same time, more dense and multiporous structure in the tissue could be obtained from the hot air and freeze drying, respectively, after microwave heating of shrimps.