• Korean Journal of Fisheries and Aquatic Sciences
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• v.25 no.5
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• pp.383-391
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• 1992

A comparative study of enzymatic properties between the trypsin from the cat-shark Cephaloscyllium umbratile ( C-T) and the two trypsins from the mackerel Scomber japonicus $(M-T_A\;and\;M-T_B)$ was carried out following after the previous paper(Pyeun et al., 1991). Trypsin from cat-shark(C-T) showed the higher heat stability compared to the others $(M-T_A\;and\;M-T_B)$ and its denaturation constant$(K_D)$ was $10.68\times10^{-4}\;sec^{-1}\;at\;55^{\circ}C$ with BA-p-NA substrate. The activation energies(Ea) of the trypsins measured at a temperature range from $30^{\circ}C\;to\;50^{\circ}C$ were estimated to be 4.07 kcal/mole for C-T, 11.61 kcal/mole for $M-T_A$, and 8.43kcal/mole for $M-T_B$, respectively. The Km values were $24.9\times10^{-5}\;M\;for\;C-T,\;5.37\times10^{-5}\;M\;for\;M-T_A,\;and\;9.65\times10^{-5}\;M\;for\;M-T_B$. On the other hand, the Ki values for TLCK and DFP determined by Dixon plot were $1.50\times10^{-6}\;M\;and\;9.28\times10^{-6}\;M\;for\;C-T\;2.86\times10^{-6}\;M\;and\;2.11\times10^{-4}\;M\;for\;M-T_A\;and\;3.90\times10^{-6}\;M\;and\;1.60\times10^{-4}\;M\;for\;M-T_B$ Similar amino acid profiles were showed between three trypsins each other, with few exceptions of $M-T_B$ containing higher amount of arginine, and the smaller amount of tryptophan in C-T than the others.

• The Korean Journal of Physiology
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• v.23 no.1
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• pp.79-87
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• 1989

Molecular property as well as biological activities of bombesin-like substance (BBS-LS) isolated from the skin of B. orientalis in Korea was compared with those of synthetic BBS-14. BBS-LS in the crude extract was applied on a Sephadex G-50, superfine column $(1.6{\times}112\;cm)$. On chromatogram, the first peak (3.5% of BBS-LS) was found ahead of synthetic GRP-27, and the second peak (rest) between synthetic GRP-27 and synthetic BBS-14. The main form of BBS-LS was successfully purified by using a column of alkaline alumina followed by sequential gel-filtrations on a column of Sephadex G-10, fine and a column of Sephadex G-50, superfine. Chromatographic analysis of the purified BBS-LS using a column of Sephadex G-50, superfine and reversed phase HPLC revealed that the main form of BBS-LS in the skin of B. orientalis could be distinctly different from either BBS-14 or GRP-27 in molecular size. The purified BBS-LS exerted biological activities quite identical to those of synthetic BBS-14. The results of the present investigation indicate that the skin of B. orientalis contains BBS-LS composed of two distinct forms. The main form of BBS-LS purified in the present study is heterogenous to both synthetic BBS-14 and GRP-27 in molecular size but identical to BBS in biological activities.

• Journal of Fisheries and Marine Sciences Education
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• v.25 no.6
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• pp.1408-1418
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• 2013

To investigate the quality properties of functional anchovy fish sauce added with raw sea tangle, 2%, 5%, and 10% (w/w) of sea tangle was added to 25% (w/w) salted anchovy and then fermented at $20^{\circ}C$. During fermentation period, the amino nitrogen contents were increased at all groups and the highest contents were at 450 days of fermentation with $11.99{\pm}0.08$, $12.51{\pm}0.08$, and $11.95{\pm}0.08mg/mL$ at 2%, 5%, and 10% addition of raw sea tangle, respectively. After later, the contents were keeping at a similar level. VBN contents were continuously increased until 270 days of fermentation with $208.10{\pm}3.50$, $210.00{\pm}4.10$, $215.15{\pm}1.50mg/100ml$ at 2%, 5%, 10% addition of raw sea tangle, respectively. Alginic acid recovery was gradually increased in fermentation duration, showed the highest concentration at 540 days of fermentation with 67.00, 67.25, 67.90% at 2%, 5% and 10% addition of raw sea tangle, respectively. Dietary fiber recovery was rapidly increased at the beginning of fermentation and then decreased slowly as the fermentation is progressed. The highest recovery was at 30 days with 18.7, 18.6, and 17.9%, and the lowest was at 360 days with 8.7 and 11.1% at 2 and 10% addition of raw sea tangle, respectively, and 450 days with 11.4% at 5% sea tangle. The lowest fucoidan contents were exhibited at 30 days of fermentation with 0.07% at both of 2% and 5% addition, and 90 days with 0.10% at 10% addtion of sea tangle. The highest fucoidan contents were 270 days showing 0.24, 0.25, and 0.23% at 2, 5, and 10% addition, respectively. All groups adding different sea tangle concentration were not significantly different at all properties. However, the newly developed products were sufficient to the standard guideline of Korea Food Drug Adminstration. The best processing process of functional anchovy fish sauce in addition with raw sea tangle is 2% addition of raw sea tangle and fermented more than 450 days. The results obtained in this study indicated that the fish sauce added with sea tangle is superior in taste, functions to traditional fish sauce and could be competitive fishery fermented food.

• Korean Journal of Medicinal Crop Science
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• v.6 no.1
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• pp.21-27
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• 1998

This experiment was conducted to increase aromatics in roots of Condonopsis lanceolata by applications of organic matters. Fresh root wt. was increased by conifer/moss application to 79.1g per plant. Crude protein content was also higher at rice straw application than native soil application and crude saponin content was increased by conifer/moss application, but contents of crude fat, fiber and ash were not different in all treatments. Although contents of K, Ca, and Mg were increased by rice straw application, Fe, Mn, Zn, Na and Cu were not significantly different in all treatments, The highest free amino acid was arginine, it was increased by the application of fallen leaves and the highest yield (0,008%) of essential oils was obtained by conifer/moss application. As a result, to produce C. lanceolata plant showing higher quality and aromatic essential oils, it was considered that the most effective organic matter showing high yield and higher aromatic constituents was conifer/moss application of over 3M/T per 10a.

• Korean Journal of Microbiology
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• v.48 no.2
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• pp.73-78
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• 2012

We previously reported that the truncated Cel44C-$Man26A_{P558}$ ${\beta}$-glycosyl hydrolase protein exhibits multifunctional activities, including cellulase, xylanase, and lichenase. DNA shuffling of the truncated Cel44C-$Man26A_{P558}$ enzyme was performed to enhance the enzymatic activity of the multifunctional ${\beta}$-glycosyl hydrolase. Two mutant enzymes, M2Cel44C-$Man26A_{P558}$ that carries one mutation (P438A) and M21Cel44C-$Man26A_{P558}$ that carries two mutations (A273T and P438A) were obtained. The enzymatic activity of the M21Cel44C-$Man26A_{P558}$ double mutant was lower than enzymatic activity of the single mutant (M2Cel44C-$Man26A_{P558}$). However, both mutants displayed the enhancements in their enzyme activities that were ${\approx}1.3$- to 2.2-fold higher than the original enzymatic activity in Cel44C-$Man26A_{P558}$. In particular, the mutant M2Cel44C-$Man26A_{P558}$ exhibited an approximate 1.5- to 2.2-fold increase in the cellulase, xylanase, and lichenase activities in comparison with the control (Cel44C-$Man26A_{P558}$). The optimum cellulase, linchenase, and xylanase activities of ${\beta}$-glycosyl hydrolase were observed at pH 7.0, pH 7.0 and pH 6.0, respectively. These results, therefore, suggest that the amino acid residue Ala438 plays important roles in the enhancement of the activity of multifunctional ${\beta}$-glycosyl hydrolase.

• Korean Journal of Agricultural Science
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• v.41 no.2
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• pp.85-99
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• 2014

Sulfonylurea (SU)-resistant weeds of eight annual weeds, Monochoria vaginalis, Scirpus juncoides and Cyperus difformis, etc., and four perennial weeds, Scirpus planiculmis, Sagittaria pigmaea, Eleocharis acicularis and Sagittaria trifolia as of 2013 since identification Monochoria korsakowii in the reclaimed rice field in 1998. And the resistant Echinochloa oryzoides to ACCase and ALS inhibitors has been confirmed in rice fields of the southern province, Korea in 2009. In the beginning, the M. vaginalis, S. juncoides and C. difformis of these SU-resistant weeds were rapidly and individually spreaded in different fields, however, these resistant weeds have been occurring simultaneously in the same filed recently. The resistant biotype by weed species demonstrated about 10-to 1,000-fold resistance, based on $GR_{50}$ values of the SU herbicides tested. And the resistant biotype of E. oryzoides to cyhalofop-butyl, pyriminobac-methyl, and penoxsulam was about 14, 8, and 11 times more resistant than the susceptible biotype base on $GR_{50}$ values. The products and applied area of SU-included herbicides have been increased rapidly, and have accounted for about 69% and 96% in Korea, respectively. In Korea, the main cause of SU-resistant weed is extensive use of these herbicides. The top ten herbicides by applied area were composed of all SU-included herbicides by 2003. The concentrated and successive treatment of ACCase and ALS inhibitors for control of barnyardgrass in rice led up to the resistance of E. oryzoides. Also, SU-herbicides like pyrazosulfuron-ethyl and imazosulfuron which effective to barnyardgrass can be bound up with the resistance of E. oryzoides. The ALS activity isolated from the resistant biotype of M. korsakowii to SU-herbicides tested was less sensitive than that of susceptible biotype. The concentration of herbicide required for 50% inhibition of ALS activity ($I_{50}$) of the SU-resistant M. korsakowii was 14-to 76-fold higher as compared to the susceptible biotype. No differences were observed in the rates of [$^{14}C$]bensulfuron uptake and translocation. Acetolactate synthase (ALS) genes from M. vaginalis resistant and susceptible biotypes against SU-herbicides revealed a single amino acid substitution of proline (CCT), at 197th position based on the M. korsakowii ALS sequence numbering, to serin (TCT) in conserved domain A of the gene. Carfentrazone-ethyl and pyrazolate were used mainly to control SU-resistant M. vaginalis by 2006 in Korea. However, the alternative herbicides such as benzobicyclone, to be possible to control simultaneously the several resistant weeds, have been developing and using broadly, because the several resistant weeds have been occurring simultaneously in the same fieled. The top ten herbicides by applied area in Korea have been occupied by products of 3-way mixture type including herbicides with alternative mode of action for the herbicide resistant weeds. Mefenacet, fentrazamide and cafenstrole had excellent controlling effects on the ACCase and ALS inhibitors resistant when they were applied within 2nd leaf stage.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.12
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• pp.1771-1777
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• 2012

This study was conducted to investigate the physicochemical characteristics of seafood added kimchi (SAK) during fermentation and its sensory properties. Korean cabbage kimchi (KCK) and four different SAKs were prepared and stored at $5^{\circ}C$ for eight weeks. The SAKs contained pre-treated octopus, squid, abalone, and webfoot octopus added at 12% (w/w) to the brined Korean cabbage. The fermentation patterns of SAKs were similar to those of KCK, indicating that the SAKs followed a typical fermentation process. Comparison of the physicochemical characteristics of SAKs with KCK revealed that the pH and acidity of SAKs was higher. The maximum concentrations of Lactobacillus spp. and Leuconostoc spp. for SAKs ranged from 8.31~8.85 and 7.60~8.14 log CFU/mL, respectively, which were higher than those for KCK. Therefore, the production of organic acids by microorganisms was greater in SAKs, which explained the higher acidities of the SAKs. Nitrogenous compounds hydrolyzed during fermentation, as well as reducing sugars and other nutritious compounds in SAKs might provide a good medium for lactic acid bacterial growth. Sensory evaluation was carried out using optimally ripened kimchi (pH $4.3{\pm}0.1$, acidity $0.7{\pm}0.1$), and the scores for sour taste, sour smell, and carbonated taste were significantly lower for SAKs than KCK. In the preference test, texture and overall acceptability were significantly higher for SAKs than KCK. Significant differences were not observed among SAKs upon subjective and preference evaluations. In conclusion, the fermentation patterns of SAKs were normal, regardless of seafood sources, and their sensory characteristics were comparable to or superior than those of KCK due to free amino acids, nitrogenous compounds produced during the fermentation, and reducing sugar present in the seafood.

• Journal of Aquaculture
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• v.17 no.2
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• pp.144-150
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• 2004

This experiment was conducted to evaluate the parameters such as nutrient requirements, POY, AnV, Totox, VBN, total plate count, dietary fatty acids and amino acids composition, that are not included in the registered standard composition items required by the Ministry of Agriculture and Forestry, of a moist pellet (MP), three domestic extruded pellets (DEP-1, DEP-2, DEP-3), and two foreign extruded pellets (FEP-1, FEP-2) that are utilized by domestic flounder farms at present. The crude protein was added in excess of the dietary protein requirement in 6 kinds of feeds. When considering the proper PH ratio, it is obvious that protein was added in excess, especially in MP and FEP-2. Crude fat was also added in excess, especially in FEP-1. MP contained a higher dietary phosphorus content than formulated feeds, surpassing the dietary phosphorus requirement and greatly increasing the possibility for causing water pollution. The oxidation of fatty acid and decomposition of protein in MP were higher than in formulated feeds, and may also cause problems on fish farms. Also, it is difficult to store and manage MP, Among the fatty acids, EPA and DHA contents in MP were higher than those in formulated feeds. It is necessary to conduct further studies of EPA and DHA contents in formulated feeds. Lysine content in MP and FEP-2 could meet the dietary lysine requirement of flounder, however, the possibility of insufficient lysine content in the other formulated feeds was high and we considered that extra supplementation was necessary. Therefore, it is necessary to set up quality control standards according to fish species and sizes while considering the specific character of aquatic formulated feeds to restore the confidence of feed companies and aquaculturists to these feeds. This may be an opportunity to make an earlier change from MP to formulated feeds.

• Korean journal of applied entomology
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• v.39 no.4
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• pp.211-226
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• 2000

Genetic divergence and phylogenetic relationships among the major Korean fireflies (Hotaria papariensis, Luciola lateralis, and Pyrocoelia rufa) were studied. A portion of mitochondrial COI (403 bp) and 165 rRNA (490~504 bp) genes were sequenced, and the GenBank-registered, homologous 165 rRNA sequences of Japanese fireflies were compared (27 species of Lampyridae, one of Lycidae, and one of Rhgophthalmidae). Greatest DNA and/or amino acid sequence divergence was found when P rufa, belonging to Lampyrinae was compared with H. papariensis and L. lateralis, both belong-ing to Luciolinae, confirming the current taxonomic status of the species. In the PAUP and PHYLIP analyses with 165 rRNA data, grouping of the two geographic samples of H. papariensis with H. tsushimana validate the use of generic name, Hotaria. Nevertheless, lack of sister-group relationship of the two geographic samples of H. papariensis renders further investigation on this group . Although the Korean and Japanese L. lateralis formed a strong monophyletic group, a substantial genetic differentiation was detected between them (2.9% of 165 rRNA gene sequence divergence). Finally, the geographic samples of Korean p. rufa strongly formed a group with Japanese p. rufa, warranting the use of generic name, Pyrocoelia, but the genetic distance observed between the Cheju-Island individual and all others requires further investigation on this subject. Summarized, this study supports the current taxonomic status of the Korean fireflies in that each respectively formed a strong monophyletic group with its own species or genus.

• Journal of Life Science
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• v.19 no.9
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• pp.1218-1225
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• 2009

Difractose anhydrides (DFAs) is studied as a sweetener for diabetics because of its structural property. DFAs have four types: DFA I, III, IV (degradation of levan) and V (degradation of inulin). Especially, DFA IV has been shown to enhance the absorption of calcium in experiments using rats. Levan fructotransferase is an enzyme for producing di-d-fructose-2,6':6,2-dianhydride (DFA IV). To identify structural characterization, we purified wild-type and mutants (D63A, D195N and N85S) of levan fructotransferase (LFTase) from Microbacterium sp. AL-210. These proteins were purified to apparent homogeneity by Ni-NTA affinity column, Q-sepharose ion exchange and gel filtration chromatography and detected by SDS-PAGE. They were also analyzed by circular dichroism (CD) measurements, JNET secondary structure prediction, activity measurements at various temperatures, and pH analysis. The optimum pH for the enzyme-catalyzed reaction was pH 7.5 and optimum temperature was observed at $55^{\circ}C$. Along with wild-type LFTase, mutants were analyzed by CD measurement, fluorescence analysis and differential scanning calorimetry (DSC). N85S showed less $\alpha$-helix and more $\beta$ strand than others. Also, N85S showed almost the same curve as wild-type in their steady-state fluorescence spectra, whereas mutant D63A and D195N showed higher intensity than wild-type. The amino acid sequence of wild-type LFTase was compared to the sequences of exo-inulinase from Aspergillus awamori, a plant fructan 1-exohydrolase from Cichorium intybus, and Thermotogo maritime (Tm) invertase and showed a high identity with Exo-inulinase from Aspergillus awamori.