• Korean Journal of Fisheries and Aquatic Sciences
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• v.23 no.1
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• pp.40-50
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• 1990

The purpose of this paper is to develop a colorant from krill, Euphausia superba, process wastes for use in food products. Carotenoproteins were extracted from preboiled krill processing offal(PKPO) and raw frozen krill processing offal(RKPO) with the aid of proteolytic enzymes. The long-term stability of the astaxanthin associated with the carotenoprotein by the addition of pretense inhibitor and antioxidant to the product were also investigated. Total astaxanthin contents of PKPO and RKPO were $35.1mg\%,\;22.1mg\%$ and those in carotenoproteins were $98.6mg\%,\;61.9mg\%$, respectively. The chitin contents of PKPO and RKPO were $6.9\%,\;4.5\%$, however, those of carotenoproteins were not determined. When $0.5\%$ trypsin was added to the extraction medium containing 0.5M $Na_3EDTA$ at $4^{\circ}C,\;74\%$ of astaxanthin and $83\%$ of the protein of PKPO were recovered as carotenoprotein in 24hrs. The amino acid profile in carotenoprotein was mainly composed of glutamic acid, methionine, aspartic acid and isoleurine. Their contents amounted to about 40% of the total amino acids, followed by alanine, phenylalanine, Iysine, leucine, threonine and tyrosine in that order, with a small amount of cysteine and tryptophan. The levels of essential amino acids were high as much as $38.3\%\~43.6\%$ of the total amino acids. The maximum observance of the carotenoid fraction from krill processing offal and from carotenoprotein was 469nm in petroleum ether. The separated components of carotenoprotein by TLC had Rfs $0.20\~0.23\;0.56\~0.60$ and $0.88\~0.91$. The carotenoids were comprised of astaxanthin, astaxanthin monoester and asthaxanthin diester in $25\~30\%\;,35\~40\%$and $40\~45\%$, respectively. The loss of carotenoids in the carotenoprotein can be prevented by the addition of pro-tease inhibitor(trasylol) and antioxidant(BHT) below $4^{\circ}C$.

• Korean Journal of Agricultural Science
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• v.15 no.2
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• pp.153-163
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• 1988

This experiment was carried out to obtain the thermophilic fungus producing amylase and to investigate properties of the amylase. The selected strain, L-11 was obtained from soil in the vicinity of a hot spring and identified as Mocor sp.. And then the conditions for enzyme production in wheat bran cultures and properties of the crude enzyme were investigated. Furthermore, the enzyme was purified and the characteristics of purified enzyme were studied. The results obtained were as follows: 1. On the wheat bran medium added 80-100% water, amylase was effectively produced by the selected strain, L-11 for 48 hrs incubation at $50^{\circ}C$. 2. When the crude enzyme solution of the strain L-11 was passed through DEAE-Sephadex A-50 column chromatography, two peaks having amylase activity were obtained, and one peak was that of the main enzyme (enzyme of B peak). 3. The purified enzyme (enzyme of B peak) was recognized as single protein band on polyacrylamide disc gel electrophoresis. 4. In the hydrolysis reaction of soluble starch by the enzyme of main amylase, oligosaccharides produced at early stage were maltose and maltotriose mainly and procedure of the reaction maltose amount of maltose and glucose was increased. 5. The strain L-11 was recognized as a special strain producing ${\alpha}-amylase$ mainly and scarcely glucoamylase. 6. The optimum pH, optimum temperature, pH stability, and temperature stability of ${\alpha}-amylase$ were pH 4.0, $60-65^{\circ}C$, pH 4.0-9.0, and below$70^{\circ}C$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.12
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• pp.1839-1846
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• 2015

The purpose of this study was to evaluate the effects of cultivar and milling degree of barley on quality characteristics of Makgeolli as well as compare differences between barley Makgeolli and rice Makgeolli. Saessal-bori groups (Ss-4, Ss-12, and Ss-18) showed dry lees contents of 92.3 g, 69.4 g, and 63.8 g, respectively, whereas Huinchalssal-bori groups (Hcs-6, Hcs-14, and Hcs-20) showed contents of 62.3 g, 42.2 g, and 32.2 g. There were significant differences in quality characteristics between milling degrees and cultivars (P<0.05). The moisture, ash, crude protein, and crude fat contents of raw materials decreased with elevated milling degree. Especially, ash content of raw materials had a direct effect on Makgeolli. The pH, total acidity, and amino acidity milling with elevated decreased degree. There were no differences in total sugar or alcohol content in Makgeolli according to milling degree of barley, whereas there were significant differences between cultivars. Barley Makgeolli showed total sugar and alcohol contents of $10.7{\sim}11.8^{\circ}Brix$ and 14.07~15.07%, respectively, which were significantly lower than $12.0{\sim}12.2^{\circ}Brix$ and 17.27~17.77% in rice Makgeolli (P<0.05). Differences in colors of raw barley according to milling degree had effects on chromaticity of Makgeolli; as milling degree increased, L and b values increased. Lactic acid bacteria counts were 7.21, 6.99, and 6.67 log CFU/mL in Ss-4, Ss-12, and Ss-18, respectively, as well as 6.14, 5.39, and 5.65 log CFU/mL in Hcs-6, Hcs-14, and Hcs-20, which suggests significant reductions with increased milling degree (P<0.05). The same trend was observed in yeast as a key quality of Makgeolli. Suspension stability differed depending on milling degree, so it is expected that suspension stability can be improved by adjusting milling degree.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.5
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• pp.401-408
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• 1985

In order to develop new types of product which can offer a sanitary and preservative duality, and convenience to consumers in marketing and cooking particularly in urban area, two processing methods of ready-to-cook food materials with dark fleshed fishes like sardine and mackerel were investigated. A method applied, in this work, is processing of ready-to-cook sardine meat "surimi" in which sardine meat is treated with alkaline solution to stabilize myofibrillar proteins, washed thoroughly with water to remove soluble components, and added with a proper amount of polyphosphate and sorbitol to enforce the functional property of meat such as water holding capasity, elasticity, and gel strength. The textural properties of fish meat paste made from the "surimi" meat were greatly dependent upon the stability of myofibrillar proteins and the elimination of water soluble components. The salt soluble proteins of sardine meat were so unstable in post-mortem stage that the gel forming ability was lost within 3 days at $5^{\circ}C$ storage and 2 to 3 weeks even at $-20^{\circ}C$ although the freshness was well kept for a week at $5^{\circ}C$ and several months of storage at $-20^{\circ}C$. A proper way of treatment to keep the proteins stable was that fish meat must be washed with $0.4\%$ sodium bicarbonate solution followed by 3 to 4 times washing with water. This resulted in removal of $80\%$ water soluble proteins and 50 to $60\%$ lipids. The addition of polyphosphate and sorbitol affected the stability of proteins during the storage of "surimi" meat. When phosphate and sorbitol were added in the ratio of $0.3\%:\;0.3\%,\;0.6\%:\;3\%,\;0.6\%:\;6\%,\;0:\,0.3\%\;and\;0.3\%:\;0$, the gel forming ability terminated in 35 days, 21 days, 14 days, 14 days, and 14 days of storage at $-30^{\circ}C$, respectively, while that of the control was 7 days. And it was also noteworthy that at least 8.0 mg/g of salt soluble protein nitrogen content was required for gel formation.

• Biomolecules & Therapeutics
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• v.20 no.1
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• pp.43-49
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• 2012

Stimulation of mast cells through the high affinity IgE receptor (Fc${\varepsilon}$RI) induces degranulation, lipid mediator release, and cytokine secretion leading to allergic reactions. Although various signaling pathways have been characterized to be involved in the Fc${\varepsilon}$RI-mediated responses, little is known about the precious mechanism for the expression of tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) in mast cells. Here, we report that rapamycin, a specific inhibitor of mammalian target of rapamycin (mTOR), reduces the expression of TNF-${\alpha}$ in rat basophilic leukemia (RBL-2H3) cells. IgE or specific antigen stimulation of RBL-2H3 cells increases the expression of TNF-${\alpha}$ and activates various signaling molecules including S6K1, Akt and p38 MAPK. Rapamycin specifically inhibits antigeninduced TNF-${\alpha}$ mRNA level, while other kinase inhibitors have no effect on TNF-${\alpha}$ mRNA level. These data indicate that mTOR signaling pathway is the main regulation mechanism for antigen-induced TNF-${\alpha}$ expression. TNF-${\alpha}$ mRNA stability analysis using reporter construct containing TNF-${\alpha}$ adenylate/uridylate-rich elements (AREs) shows that rapamycin destabilizes TNF-${\alpha}$ mRNA via regulating the AU-rich element of TNF-${\alpha}$ mRNA. The antigen-induced activation of S6K1 is inhibited by specific kinase inhibitors including mTOR, PI3K, PKC and $Ca^{2+}$chelator inhibitor, while TNF-${\alpha}$ mRNA level is reduced only by rapamycin treatment. These data suggest that the effects of rapamycin on the expression of TNF-${\alpha}$ mRNA are not mediated by S6K1 but regulated by mTOR. Taken together, our results reveal that mTOR signaling pathway is a novel regulation mechanism for antigen-induced TNF-${\alpha}$ expression in RBL-2H3 cells.

• Journal of Nutrition and Health
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• v.18 no.4
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• pp.259-271
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• 1985

The purpose of this study was to develop supplementary foods for infants and young children in order to improve their nutritional status. Three formulas composed of rice, soybeans, fish, dry skim milk and sesame in varying proportions were studied. The three formulas, $RS_{1}S_{2}$, $RFS_{1}S_{2}$, and $RMS_{1}S_{2}$, were consisted of Rice(R), Soybean$(S_{1})$, Sesame$(S_{2})$ (60 : 35 : 5) , Rice, Fish(F), Soybean, Sesame (60 : 10 : 25 : 5) , and Rice, Dry Skin Milk (M), Soybean, Sesame (60 : 10 : 25 : 5), respectively. A proximate analysis and amino acid determination were made on the developed formulas. In the animal assay, growth rate, PER and FER were evaluated and biochemical analyses were also carried out. A storage test and the cost evaluation were also conducted. The summarized results are as follows : 1) The proximate composition of the three formulas were 7.3-7.4% of moisture, 15.9-21.5% of crude protein, 7.8-9.6% of crude fat and 2.5-2.8% ash. 2) The result of amino acid analysis showed that the 1st limiting amino acids of $RS_{1}S_{2}$ and $RFS_{1}S_{2}$ were lysine (amino acid score, 76.6) and threonine (amino acid score, 93.3), and that of $RMS_{1}S_{2}$ and the commercially prepared formula were sulfur containing amino acids (amino acid score, 82.0 and 54.4). When the contents of the amino acids of the three formulas were compared with mother's milk and cow's milk, the balance of the amino acid of each formula was superior to mother's milk but inferior to cow's milk. 3) In the animal assay, the growth rate of all groups increased gradually during the experimental period. 4) The C- PER, which was corrected on the basis of the casein PER of 2.5 was 2.99, 3.38 and 3.10 in the $RS_{1}S_{2}$, $RFS_{1}S_{2}$ and $RMS_{1}S_{2}$ respectively. The C- PER of $RFS_{1}S_{2}$ and $RMS_{1}S_{2}$ were Significantly (P<.05) higher than that of the casein. 5) The FER of the casein, $RS_{1}S_{2}$, $RFS_{1}S_{2}$, and $RMS_{1}S_{2}$ were 0.37, 0.39, 0.43 and 0.39, respectively. The FER of $RFS_{1}S_{2}$ and $RMS_{1}S_{2}$ were also significantly (P<.05) higher than that of the casein. 6) The concentrations of hematocrit, hemoglobin, total protein and albumin in the serum of the rats of all groups were not significantly different among groups. 7) The storage stability test showed that the total plate count (TPC), the coliforms count and the bacterial spore count in the ingredients were quiet low. However, after 30 and 60 days storage, the count in $RFS_{1}S_{2}$ increased and were higher at room temperature than refrigerated temperature. 8) In the cost evaluation, the cost of the developed formulas was \1,826-2,626 / kg. This was less than that of the commercially prepared formula (\3,300-4,073 / kg) and that of the imported formula (\4,250-8,720 / kg).

• Korean Journal of Food Science and Technology
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• v.32 no.4
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• pp.755-762
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• 2000

Physicochemical properties of commercial sweet potato starches manufactured by 7 different companies were investigated in comparison with corn and potato starches. Crude ash and protein content varied from 0.36 to 1.02%, and from 0.04 to 0.14% based on dry weight, respectively. The protein contents were relatively smaller than that of corn or potato starch. But whiteness of the sweet potato starches was less than that of corn or potato starch. Mean diameter of the sweet potato starch granules varied from 14.23 to $21.08\;{\mu}m$ depending on the company and all sweet potato starches showed bimodal size distributions. Pasting viscosity measured by Rapid Viscoanalyzer(RVA) also showed variations among the starches of different companies. The starch from D company in Korea had the lowest pasting temperature$(74.00^{\circ}C)$ whereas the starch from a phillippine company(P) did the highest one$(80.35^{\circ}C)$. The peak viscosity of sweet potato starches was higher than that of corn starch but lower than that of potato starch. The D company starch also showed the highest peak viscosity(2283 cp) among the starches tested. Paste breakdown by hot shearing ranged from 524 cp (S company) to 1279 cp (HL company). Textural properties of the starch gels appeared significantly different among the starches of different manufacturers. The greatest hardness of the gel was $137.90\;g_{f}$ at 1 day storage whereas the lowest value was $31.53\;g_{f}$. Except the starches from 2 companies (P and S), the sweet potato starches formed very soft and weak gels. P or S company starches formed the gels similar to potato starch. Syneresis by freeze-thawing treatments appeared less for sweet potato starch gels than that for corn starch gels, but greater than that for potato starch gel. The overall properties of the sweet potato starches varied by the manufacturing companies, and ranged between those of corn and potato starches.

• Journal of Life Science
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• v.19 no.9
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• pp.1226-1231
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• 2009

Enzyme substitution with recombinant phenylalanine ammonia-lyase (PAL, EC 4.3.1.5) is currently being explored for treatment of phenylketonuria (PKU), an autosomal recessive genetic disorder with mutations of the gene encoding phenylalanine-4-hydroxylase (EC 1.14.16.1). However, oral administration of PAL is limited because of proteolytic digestion in the gastrointestinal tract. The aim of this study was to determine the biochemical properties of PAL and delinate the susceptibility of wild-type PAL to pancreatic proteolysis by exploring several mutants, and to develop therapeutic drugs with PAL for PKU. The specific activity of PAL was assayed and its optimal pH, temperature stability, and intestinal protease susceptibility were investigated. Its $V_{max}$ values for phenylalanine and tyrosine were 1.77 and $0.47{\mu}mol$/ min/mg protein, respectively, and its $K_m$ values were $4.77{\times}10^{-4}$ and $4.37{\times}10^{-4}\;M$, respectively. PAL showed an optimal pH at 8.5, corresponding to the average pH range of the small intestine. It showed no loss of activity at $-80^{\circ}C$ for 5 months and possessed 93.4% of its activity under $4^{\circ}C$ for 4 wks. PAL was susceptible to chymotrypsin digestion and, to a lesser extent, to trypsin, elastase, carboxypeptidase A, and B. The trypsin and chymotrypsin cleaving sites were mutated to investigate protection from pancreatic digestion and the specific activities of these mutants were evaluated. The six mutants displayed low specific activities compared to the wild-type, suggesting that the primary trypsin and chymotrypsin cleaving sites may be essential for catalytic reaction. The PAL mutants could therefore be applied as a pretreatment modality without susceptibility to proteolytic attack, however, additional modification for enhancing enzymatic activity is needed to reduce the Phe levels effectively.

• Korean journal of food and cookery science
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• v.16 no.6
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• pp.593-601
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• 2000

Seven domestic wheat cultivars, Suwon 261, Suwon 265, Eunpa, Kobun, Alchan, Olgru, and Kumgang, and a standard wheat, ASW(Australian Standard White Wheat), were compared in noodle-making properties. The ash contents of domestic wheats and flours were 0.1-0.3% higher than that of ASW. Therefore, domestic wheats required the control of ash contents during milling process. The protein contents which suggest the flour gluten content were 10.32, 11.3, and 9.57% in Suwon 261, Suwon 265, and Kumgang cultivars, respectively. Valorimeter values of Eunpa, Olgru, and Kumgang which indicate the dough formation time and stability were similar to that of ASW. Resistance rate of domestic wheats was lower than that of ASW. Maximum viscosity in Amylograph for Eunpa, Olgru, and Kumgang were in the range of 500-800BU, which were suitable for making noodles. Increase in weight and volume of Olgru noodle was negatively correlated with protein content. Turbidity was not positively correlated with weight and volume increase, but domestic cultivars except Suwon 265 and Eunpa showed a similar turbidity with ASW. The mechanical properties of wet and dry noodles were evaluated by TPA test before and after cooking. Springiness and cohesiveness of wet noodles increased by cooking, and the domestic cultivars showed higher values than ASW. Springiness and cohesiveness of dry noodle were not increased by cooking in any cultivars. Gumminess, chewiness and hardness of domestic wheat cultivars showed higher values than that of ASW. In the tensile test, wet noodles showed no difference between domestic cultivars and ASW. But dry noodles of domestic wheat cultivars showed higher values than ASW. In the color test for lightness, redness and yellowness, there were no differences between flour and dough of domestic wheat cultivars and ASW. In the sensory evaluation, Kumgang wheat cultivar was the most preferred among the wet and dry noodles of other domestic wheat cultivars and ASW. These results suggested Kumgang wheat cultivar to be a practical wheat variety for noodle-making.

• The Korean Journal of Nuclear Medicine Technology
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• v.16 no.2
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• pp.139-148
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• 2012

Purpose : Since standard solution is the one that knows its exact concentration, the curve of the dissolution has been determined according to the amount of the solution, compared to the amount of the unknown sample. Therefore, the antigen that makes up standard materials should be made in a pure form. The configuration of the standard substance solution in the kit we use is a freeze-dried material, or made and comes as a liquid. Lyophilized reference material is used after dissolving in usually D.W. (Distilled Water), and if the antigen to use is too sensitive, reagents should be freeze-dried. Furthermore, when freeze-dried reference has to be frozen again after being dissolved, it should be kept under $-20^{\circ}C$ until the expiration date according to the reports. Since it is not expressed in the experiment if it is safe or stable to reuse the solution which was dissolved a few times, thus, this time it is tested and evaluated that the changes of the standard solution by freezing and melting several times, and its results and the effectiveness of it were compared to the solution which was kept in a fridge. Materials and Methods : Among Vitro diagnostic kits on the market made by radioimmunoassay, parathyroid hormone (PTH), adrenocorticotropic hormone (ACTH), luteinizing hormone (LH) are made of freeze-dried standard solution and all composed of the same Lot.NO. These hormones melted in D.W. and were separated into three groups. In the first group, melting and freezing were repeated, and in the second group, The solution only for one time use was put into a test tube after melting and freeze it. The third group was kept in the refrigerator. This experiment has been conducted from January to February in 2012. January to 2012. PH test was employed because ph is prone to changing depending on the change of protein. Each group of the standard solution, cpm (counter per minute), and the patient relative concentration values were compared by date, and Through the correlation coefficient and Paired t-test, the significant level of each group was analyzed. Results : ACTH, PTH, LH pH values were too subtle denaturation rather than numerical changes in the protein. In addition, when the standard solution of ACTH, PTH, LH was refrigerated, after 3 days and 7 days, there was a significant difference observed between the solution being kept in a refrigerator and a freezer within a significance level. Conclusion : Standard solution should be kept in a freezer, and being kept in a fridge, it is recommended to use the solution as soon as possible.