• Korean Journal of Food Science and Technology
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• v.14 no.1
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• pp.36-42
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• 1982

An investigation on optimum processing conditions for meaty textured fish protein concentrate (MT-FPC) was carried out with the fish meat of filefish, Navodon modestus, and sandfish. Arctoscopus japonicus. The processing conditions were determined by the lipid content and the rehydration capacity of MT-FPC. The optimum pH and sodium chloride content of fish meat were 8.0 and 1.0%, respectively. The most effective soaking conditions were: soaking time in chilled ethanol was 15 min for both filefish and sandfish; amount of chilled ethanol, 3 volumes and 4 volumes for filefish and sandfish, respectively; temperature of chilled ethanol, $25 ^{\circ}C$ for both filefish and sandfish; soaking time in boiling ethanol, 15 and 25 min for filefish and sandfish, respectively; amount of boiling ethanol, 2 and 4 volumes for filefish and sandfish, respectively; and number of snaking in boiling ethanol, 2 and 4 times for filefish and sandfish, respectively. Yields of the product to the minced meat weight, the contents of protein and lipid in MT-FPC prepared from filefish were 13.7%, 84.5% and 0.2%, and those from sandfish were 12.5%, 84.2% and 1.1%, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.17 no.3
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• pp.242-248
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• 1988

Plasteins were synthesized from a peptic sardine protein hydrolysate by pepsin, ${\alpha}-chymotrypsin$ pretense(from Aspergillus saitoi) and papain under the optimum conditions of previous paper. L -glutamic acid diethylester and L-leucine ethylester also were incorporated into plastein during the plastein reaction by papain. General composition, yield, molecular weight and amino acid composition were measured. The protein, ash and lipid rontent of plasteins were $81.1{\sim}88.2%$, $1.9{\sim}7.6%$ and $0.3{\sim}0.8%$, respectively. The yield of plasteins were pretense plastein 52.3%, papain plastein 44.2%, pepsin plnstein 43.6%, ${\alpha}-chymotrypsin$ plastein 43.2%. Leu -papain plastein 33. 2% and Glu - papain plastein 29.0%. The glutamic acid and leucine content in Glu -papain plastein and Leu -papain plastein were 39.0%, 37.5%, respectively. While the contents in the papain plastein were 14.3%, 7.1%, respectively. The amino acid composition of plasteins were similar to that of peptic sardine protein hydrolysate. The major molecular weight of the peptic hydrolysnte estimated by gelfilteration were 1,800 and 285, and those of plasteins were 26,000 and 9,100 for ${\alpha}-chymotrypsin$, 23,000, 10,000 and 4,300 for pepsin, 18,000 for pretense, 13,000 for papain, 29,000 for Leu -papain plastein and 19,000 for Glu -papain plastein.

• Journal of Microbiology and Biotechnology
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• v.15 no.4
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• pp.815-822
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• 2005

In order to extend the shelf-life of packaged or coated foods, an antibacterial edible film was developed from soybean meal that had been fermented with Bacillus subtilis under the optimum condition of pH 7.0-7.5 and $33^{\circ}C$ for 33 h. The water vapor permeability of the fermented film ($86.0 mg/cm^2{\cdot}h$) was higher than those of normal soybean films ($66.9 mg/cm^2{\cdot}h$). Protein solubility of the fermented film was also higher than ordinary soy protein film at the pH range of 3 -10. The fermented soybean film had higher tensile strength and lower $\%$ elongation (elongation rate) than the ordinary soybean film, mainly because partial hydrolysis of proteins in the soybean film occurred during fermentation. Antimicrobial properties of the fermented film on foodstuffs were measured by placing the films on surime, jerked beef, and mashed sausage media; containing $10^2-10^3$ CFU/plate of foodborne pathogenic bacteria, and showed significantly higher inhibitory effects on the growths of all the indicating bacteria. The film could be used as a packaging material in the food industry. However, before direct application of the fermented film to the commercial food industry, its poor mechanical and antibacterial properties need to be improved.

• The Korean Journal of Physiology and Pharmacology
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• v.18 no.6
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• pp.517-524
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• 2014

Phasic and tonic ${\gamma}$-aminobutyric acidA ($GABA_A$) receptor-mediated inhibition critically regulate neuronal information processing. As these two inhibitory modalities have distinctive features in their receptor composition, subcellular localization of receptors, and the timing of receptor activation, it has been thought that they might exert distinct roles, if not completely separable, in the regulation of neuronal function. Inhibition should be maintained and regulated depending on changes in network activity, since maintenance of excitation-inhibition balance is essential for proper functioning of the nervous system. In the present study, we investigated how phasic and tonic inhibition are maintained and regulated by different signaling cascades. Inhibitory postsynaptic currents were measured as either electrically evoked events or spontaneous events to investigate regulation of phasic inhibition in layer 2/3 pyramidal neurons of the rat visual cortex. Tonic inhibition was assessed as changes in holding currents by the application of the $GABA_A$ receptor blocker bicuculline. Basal tone of phasic inhibition was maintained by intracellular $Ca^{2+}$ and $Ca^{2+}$/calmodulin-dependent protein kinase II (CaMKII). However, maintenance of tonic inhibition relied on protein kinase A activity. Depolarization of membrane potential (5 min of 0 mV holding) potentiated phasic inhibition via $Ca^{2+}$ and CaMKII but tonic inhibition was not affected. Thus, phasic and tonic inhibition seem to be independently maintained and regulated by different signaling cascades in the same cell. These results suggest that neuromodulatory signals might differentially regulate phasic and tonic inhibition in response to changes in brain states.

• Journal of Microbiology
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• v.39 no.3
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• pp.168-176
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• 2001

Five different types of catalases from photosynthetic bacterium Rhodospirillum rubrum S1 grown aerobically in the dark were found in this study, and designated Catl (350 kDa), Cat2 (323 kDa), Cat3 (266 kDa), Cat4 (246 kDa), and Cat5 (238 kDa). Analysis of native PAGE revealed that Cat2, Cat3, and Cat4 were also produced in the cells anaerobically grown in the light. It is notable that only Cat2 was expressed much more strongly in response to the anaerobic condition. Enzyme activity staining demonstrated that Cat3 and Cat4 had bifunctional catalase-peroxidase activities, while Catl, Cat2, and Cat5 were typical monofunctional catalases. S1 cells grown aerobically in the presence of malate as the sole source of carbon exhibited an apparent catalase Km value of 10 mM and a Vmax of about 705 U/mg protein at late stationary growth phase. The catalase activity of Sl cells grown in the anaerobic environment exhibited a much lower Vmax of about 109 U/mg protein at late logarithmic growth phase. The catalytic activity was stable in the broad range of temperatures (30$\^{C}$-60$\^{C}$), and pH (6.0-10.0). R. rubrum S1 was much more resistant to H$_2$O$_2$in the stationary growth phase than in the exponential growth phase regardless of growth conditions. Cells of stationary growth phase treated with 15 mM H$_2$O$_2$for 1 h showed 3-fold higher catalase activities than the untreated cells. In addition, L-glutamate induced an 80-fold increase in total catalase activity of R. rubrum S1 compared with magic acid. Through fraction analyses of S1 cells, Cat2, Cat3, Cat4 and Cat5 were found in both cytoplasm and periplasm, while Catl was localized only in the cytoplasm.

• The Korean Journal of Physiology
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• v.25 no.1
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• pp.27-35
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• 1991

Generally, it has been known that cholecystokinin (CCK) release into the plasma is under cholinergic control, but secretin release is not. Thus in anesthetized dogs we studied the effect of atropine $(50\;{\mu}g/kg\;followed\;by\;50\;{\mu}g/kg/hr)$ on pancreatic secretion and plasma concentrations of bioactive CCK and immunoreactive secretin in response to intraduodenal perfusion of sodium oleate (1, 3 and 9 mmol/hr). The volume, protein output and bicarbonate output of the secretion were increased by sodium cleats and this oleate-induced secretion was decreased significantly by atropine administration. However the increased plasma CCK and secretin levels by sodium oleate were not changed by atropine. These results indicate that atropine suppressed sodium oleate-induced pancreatic secretion through inhibiting cholinergic mechanism directly rather than decreasing the release of pancreatic secretory hormones. In another set of experiments, bilateral cervical vagi were stimulated electrically to observe the changes of pancreatic secretion and the above two plasma hormone levels in the presence or absence of atropine. In the vagally stimulated dogs, the volume, protein output and bicarbonate output of the pancreatic secretion were increased significantly. Both plasma secretin and CCK were concomitantly released significantly by vagal stimulation. Atropine significantly depressed the pancreatic secretory response as well as the release of these two pancreatic secretory hormones. Therefore, we conclude that in the presence of atropine the depressed pancreatic response to vagal stimulation is at least, in part, due to decreased release of endogenous CCK and secretin. In the vagally stimulated animals, however, the involvement of direct cholinergic influence on pancreatic exocrine gland remains to be answered.

• The Korean Journal of Physiology and Pharmacology
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• v.5 no.5
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• pp.443-449
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• 2001

Previously we reported that THI 52 inhibits tumor necrosis factor $(TNF)-{\alpha}$ mRNA expression in mouse peritoneal macrophages exposed to LPS plus $IFN-{\gamma}.$ In the present study, the effects of THI 52 on vascular reactivity ex vivo, and iNOS protein expression (rat lung) were investigated in LPS-treated rats. Treatment of THI 52 concentration-dependently reduced not only serum nitrite production but also the expression of iNOS protein in rat lung tissues. Thoracic aorta taken from LPS injected rat for 8 h ex vivo resulted in suppression of vasoconstrictor effects to phenylephrine (PE), which was restored by THI 52 (20 mg/kg) 30 min prior to LPS. When measured iNOS activity, treatment of THI 52 concentration-dependently reduced the enzyme activity in RAW 264.7 cells activated with LPS plus $IFN-{\gamma}.$ Likewise, iNOS activity was significantly reduced in lung tissues taken those rats that were injected THI 52 prior to LPS injection compared with LPS injection alone. These results strongly suggest that THI 52 can suppress iNOS gene expression induced by LPS, and restore the vascular contractility to PE. Thus, THI 52, a new synthetic isoquinoline alkaloid, may be beneficial in inflammatory disorders where production of NO is excessed by iNOS expression.

• The Plant Pathology Journal
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• v.31 no.2
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• pp.123-131
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• 2015

Clavibacter michiganensis subsp. sepedonicus (Cms) multiplies very rapidly, passing through the vascular strands and into the stems and petioles of a diseased potato. Therefore, the rapid and specific detection of this pathogen is highly important for the effective control of the pathogen. Although several PCR assays have been developed for detection, they cannot afford specific detection of Cms. Therefore, in this study, a computational genome analysis was performed to compare the sequenced genomes of the C. michiganensis subspecies and to identify an appropriate gene for the development of a subspecies-specific PCR primer set (Cms89F/R). The specificity of the primer set based on the putative phage-related protein was evaluated using genomic DNA from seven isolates of Cms and 27 other reference strains. The Cms89F/R primer set was more specific and sensitive than the existing assays in detecting Cms in in vitro using Cms cells and its genomic DNA. This assay was also able to detect at least $1.47{\times}10^2copies/{\mu}l$ of cloned-amplified target DNA, 5 fg of DNA using genomic DNA or $10^{-6}$ dilution point of 0.12 at $OD_{600}$ units of cells per reaction using a calibrated cell suspension.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.5
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• pp.557-561
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• 2010

This feeding experiment was conducted to investigate the effects of dietary inclusion of some additives on growth performance, hematological parameter and fatty acid composition of growing flounder. Triplicate groups of fish (average weight 120 g) were fed one of five diets containing 5% kelp meal (Ke), 10% krill meal (Kr), 1% garlic powder (Ga), 1% citrus meal (Ci) or control diet (Con) without supplementation for 15 weeks. After the feeding experiment, survival was not significantly different among the groups fed the different diets. Weight gain of fish fed the Ci diet was significantly higher than that of fish fed the Kr diet, but not significantly different from Con, Ke and Ga treatments. Feed efficiency and protein efficiency ratio of fish fed the Ga diet were significantly higher than those of fish fed the other diets. Total protein, glucose, GOT, GPT and total cholesterol contents in the plasma were not affected by the dietary additives. Composition of C20:4n-6 in the dorsal muscle of fish fed the Con diet was significantly higher than that of fish fed the other diets. The results of this study suggest that the dietary inclusion of garlic meal at 1% may improve feed utilization of growing flounder.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.6
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• pp.810-817
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• 2014

Two consecutive feeding trials were conducted to evaluate the effects of extruded pellet (EP) and raw fish-based moist pellet (MP) in the juvenile (experiment I) and sub-adult (experiment II) stages of olive flounder, Paralichthys olivaceus. The fish were distributed randomly to three aquarium tanks, as a group of 1,200 fish (initial mean weight $13.5{\pm}1.76g$) in experiment I, and as a group of 390 fish (initial mean weight $385{\pm}15.3g$) in experiment II. In experiment I, the weight gain, specific growth rate, feed efficiency, protein efficiency ratio, and survival of fish fed EP were all significantly higher than those of fish fed MP. In experiment II, no significant differences were observed in weight gain, specific growth rate and survival between the EP and MP groups. However, the feed efficiency and protein efficiency ratios of fish fed EP were significantly higher than those of fish fed MP. The results of this study indicate that EP could be developed to replace MP for market size production of olive flounder without any adverse effects on the growth performance. The dietary formulation used in this study could be used as an appropriate feed for olive flounder.