• 한국수산과학회지
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• 제48권3호
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• pp.275-283
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• 2015

This study compared the sensory and nutritional characteristics of mottled skate Beringraja pulchra caught off Ulleung Island (U-MS), Korea, with those caught off Daecheong Island (D-MS). Based on their trichloroacetic acid-soluble nitrogen content, free amino acid content, and taste value, the taste of intermediate weight female U-MS was superior to that of both other U-MS and D-MS. The urea content of U-MS was higher in females than males and increased in the order heavy>intermediate>light individuals. There was, however, no difference in urea content between U-MS and D-MS. The taste and flavor characterization results suggest that the level of ammonia, which was converted from urea, influenced the quality of fermented U-DS. With the exception of the light U-DS, the other U-MS exhibited no difference in terms of hardness. The total amino acid content of U-MS was higher in females than males and increased in the order intermediate > heavy > light individuals. The total amino acid content of U-MS was also higher than that of D-MS. The major amino acids of all MSs were aspartic acid, glutamic acid, leucine, and lysine.

• 한국축산식품학회지
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• 제36권5호
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• pp.641-649
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• 2016

In this study, we compared qualities and physiochemical traits of meat from Berkshire (black color) pigs with those of meat from 3-way Landrace (white color) × Yorkshire (white color) × Duroc (red color) crossbred pigs (LYD). Meat quality characteristics, including pH, color, drip loss, cooking loss, and free amino acid, fatty acid, vitamin, and mineral contents of longissimus dorsi muscles, were compared. Meat from Berkshire pigs had deeper meat color (redness), higher pH, and lower drip loss and cooking loss than meat from LYD pigs. Moreover, meat from Berkshire pigs had higher levels of phosphoserine, aspartic acid, threonine, serine, asparagine, α-aminoadipic acid, valine, methionine, isoleucine, leucine, tyrosine, histidine, tryptophan, and carnosine and lower levels of glutamic acid, glycine, alanine, and ammonia than did meat from LYD pigs. The fatty acids oleic acid, docosahexaenoic acid (DHA), and monounsaturated fatty acids (MUFA) were present in significantly higher concentrations in Berkshire muscles than they were in LYD muscles. Additionally, Berkshire muscles were significantly enriched with nucleotide components (inosine), minerals (Mg and K), and antioxidant vitamins such as ascorbic acid (C) in comparison with LYD muscles. In conclusion, our results show that in comparison with LYD meat, Berkshire meat has better meat quality traits and is a superior nutritional source of all essential amino acids, monounsaturated fatty acids, vitamin C, and minerals (Mg and K).

• Journal of Microbiology and Biotechnology
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• 제23권4호
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• pp.572-578
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• 2013

Azotobacter vinelandii, a strict aerobic nitrogen-fixing bacterium, has been extensively studied with regard to the ability of $N_2$-fixation due to its high expression of nitrogenase and fast growth. Because nitrogenase can also reduce cyanide to ammonia and methane, cyanide degradation by A. vinelandii has been studied for the application in the bioremediation of cyanide-contaminated wastewater. Cyanide degradation by A. vinelandii in NFS (nitrogen-free sucrose) medium was examined in terms of cell growth and cyanide reduction, and the results were applied for cyanide-contaminated cassava mill wastewater. From the NFS medium study in the 300 ml flask, it was found that A. vinelandii in the early stationary growth phase could reduce cyanide more rapidly than the cells in the exponential growth phase, and 84.4% of cyanide was degraded in 66 h incubation upon addition of 3.0 mM of NaCN. The resting cells of A. vinelandii could also reduce cyanide concentration by 90.4% with 3.0 mM of NaCN in the large-scale (3 L) fermentation with the same incubation time. Finally, the optimized conditions were applied to the cassava mill wastewater bioremediation, and A. vinelandii was able to reduce the cyanide concentration by 69.7% after 66 h in the cassava mill wastewater containing 4.0 mM of NaCN in the 3 L fermenter. Related to cyanide degradation in the cassava mill wastewater, nitrogenase was the responsible enzyme, which was confirmed by methane production. These findings would be helpful to design a practical bioremediation system for the treatment of cyanide-contaminated wastewater.

• The Korean Journal of Ecology
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• 제18권1호
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• pp.1-15
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• 1995

Alakline phosphatase activity (AP A) as a phosphorus deficiency measurement in flowing waters and of microhabitats (rocks, wood, leaves, and sediments) was measured and its relationship to flux of nutrients and response to rainfall events were determined for two geologically different streams in west Alabama from August to November. Results indicated water column AP A in both streams had a low correlation with levels of orthophosphate, total organic phosphorus, nitrate, ammonia, dissolved organic carbon, and discharge (r=0.075-0.583; n=g-IU. Communities on rock surfaces showed a higher AP A level than those on wood and leaves. Sediment passed through a $106{\mu}m$ sieve showed 2-9 times higher AP A level than material passed through $425{\mu}m$ sieve. The first storm after drought at Yellow Creek introduced substantial quantities of DOC (2.5 times baseflow concentrations) and $N0_3-N$ (5.8 times baseflow concentrations) which did not affect AP A significantly. The second storm at Little Schultz Creek caused minor changes in nutrient cocentrations; however $N0_3-N$ levels and AP A were drastically lower due to the dilution effect. Retention of stream water AP A at Yellow Creek and Little Schultz Creek on $0.45{\mu}m$ filter (54 and 43%, respectively) and $0.22{\mu}m$ (83 and 77% of total APA. respectively) indicated more free dissolved portion of the enzyme was present at Little Schultz Creek. Little Schultz Creek (with carbonate and with a higher productivity and biomass) showed a consistantly greater AP A activity $(132{\pm}54\;{\mu}M{\cdot}1^{-1}{\cdot}min^{-I};\;n=g)$ than Yellow Creek $(41{\pm}23\;{\mu}M{\cdot}1^{-I}{\cdot}min^{-I}$, with a sandstone substrate; n=l1, $p{\leq}O.OO1)$. Overall, a greater APA on all microhabitats and the presence of more dissolved enzyme in Little Schultz Creek during the study period may indicates it is more P deficient than Yellow Creek.

• 한국수소및신에너지학회논문집
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• 제22권5호
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• pp.649-655
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• 2011

Methane direct cracking can be utilized to produce $CO_x$ and $NO_x$-free hydrogen for PEM fuel cells, oil refineries, ammonia and methanol production. We present the results of a systematic study of methane direct cracking using a mixed conducting oxide, Y-doped $BaZrO_3$ ($BaZr_{0.85}Y_{0.15}O_3$), membrane. In this paper, dense $BaZr_{0.85}Y_{0.15}O_3$ membrane with disk shape was successfully sintered at $1400^{\circ}C$ with a relative density of more 93% via addition of 1 wt% ZnO. The ($BaZr_{0.85}Y_{0.15}O_3$) membrane is covered with Pd as catalyst for methane decomposition with an DC magnetron sputtering method. Reaction temperature was $800^{\circ}C$ and high purity methane as reactant was employed to membrane side with 1.5 bar pressure. The $H_2$ produced by the reaction was transported through mixed conducting oxide membrane to the outer side. In addition, it was observed that the carbon, by-product, after methane direct cracking was deposited on the Pd/ZnO-$BaZr_{0.85}Y_{0.15}O_3$ membrane. The produced carbon has a shape of sphere and nanosheet, and a particle size of 80 to 100 nm.

• Korean Chemical Engineering Research
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• 제45권6호
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• pp.611-618
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• 2007

아민기로 코팅된 단분산 폴리스티렌 입자를 제조한 뒤 톨루엔-물로 구성된 유중수 액적(oil-in-water emulsion) 내부에서 입자를 자기 조립(self-assembly)시켜 다양한 다면체(polyhedra) 구조의 콜로이드 클러스터(colloidal cluster)를 제조하였다. 콜로이드 클러스터의 표면에서 솔-젤(sol-gel) 반응을 유발한 뒤 표면이 실리카로 코팅된 복합(composite) 콜로이드 클러스터를 제조할 수 있었고 이를 주형(template)으로 활용하여 고온 소성에 의해 내부의 폴리스티렌 입자를 제거하고 마이크로미터 크기의 다양한 구조의 비구형상 공동 입자(hollow particle)를 제조하였다. 밀도구배원심분리법 (density gradient centrifugation)에 의해 폴리스티렌 구성 입자의 수와 구조가 균일한 콜로이드 클러스터를 제조할 수 있었으며 표면 솔-젤 반응에 의해 비구형상 구조의 공동 입자를 제조하였다.

• 한국토양비료학회지
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• 제10권2호
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• pp.85-92
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• 1977

인산감수성(燐酸感受性)이 다른 9개대두재배종(個大豆栽培種) Lee, Hill, Harosoy, Clark-63, Chippewa 및 R56-49을 서로 다른 질소원(窒素源)으로 수경재배(水耕栽培)하여 엽중유리당(葉中遊離糖)과 유기산(有機酸)을 gas chronatograph로 조사(調査)하여 미동정(未同定)의 X, Y peak와 Sucrose peak가 주(主) peak로 나타났다. X 화합물(化合物)은 NO3-N 급여(給與)경우 흔적으로 나타난데 반하여 NH4-N나 urea 급여(給與)경우에 다량(多量)나타났다. Y 화합물(化合物)을 Urea 급여(給與)경우 감소하는 경향이었다. Sucrose는 NH4-N 급여(給與)에서 흔적으로 나타나고 Urea에서 NO3-N에서보다 높았다. X 화합물(化合物)은 erythrose에서 유래(由來)한 4 탄소(炭素) 산성당(酸性糖)이거나 Purine이나 Pyrimidine에서 유래(由來)한 환상화합물(環狀化合物)로 Y 화합물(化合物)은 glycolysis path에서 유래(由來)한 6 탄당(炭糖)으로 추정(推定)되었다. Y/X 치(値)는 인산감수성(燐酸感受性)의 좋은 지표(指標)가 되므로(역관계(逆關係)) 이 두 화합물(化合物)은 ammonia 독작용(毒作用) 및 인산감수성(燐酸感受性) 기작(機作)에 관여(關與)하는 요인화합물(要因化合物)로 보였다.

• 한국식품과학회지
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• 제34권3호
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• pp.466-471
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• 2002

고추장의 저장성 향상을 목적으로 숙성이 완료된 고추장에 마늘이나 알콜, 키토산, K-sorbate, 겨자를 첨가하거나 저온살균 처리를 하여 포장하고 $30^{\circ}C$에서 24주간 저장하면서 화학성분의 변화를 비교하였다. 고추장의 pH는 저장 중에 저하하였고 적정산도는 저장 8주 이후에 감소하나 겨자와 마늘 첨가구에서 높았다. 환원당은 저장 $16{\sim}20$주에 증가하여 K-sorbate와 알콜 첨가구에서 높았고, 알콜의 증가는 대조구와 키토산 첨가구에서 심하였다. 아미노태 질소 함량은 알콜이나 마늘, K-sorbate, 겨자 첨가구에서 낮았다. 유리 아미노산은 저장 중에 증가하였고 저온 살균구와 마늘, 알콜 첨가구에서 많았다. $30^{\circ}C$에서 24주 저장한 고추장의 관능치는 유의성은 없으나 맛은 K-sorbate와 마늘, 겨자 첨가구, 색은 저온 살균구와 K-sorbate, 알콜 첨가구, 향기는 마늘과 키토산 첨가 고추장이 우수하여 종합적인 기호도에서 K-sorbate와 마늘, 알콜 첨가 고추장이 좋았다.

• Asian-Australasian Journal of Animal Sciences
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• 제32권10호
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• pp.1521-1527
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• 2019

Objective: To study the contribution of plant enzyme and microbial activities on protein degradation in silage, this study evaluated the nitrogen transformation dynamics during ensiling of non- and irradiated alfalfa (Medicago sativa L.) and red clover (Trifolium pratense L.). Methods: Alfalfa and red clover silages were prepared and equally divided into two groups. One group was exposed to ${\gamma}$-irradiation at a recommended dosage (25 Gky). Therefore, four types of silages were produced: i) non-irradiated alfalfa silage; ii) irradiated alfalfa silage; iii) non-irradiated red clover silage; and iv) irradiated red clover silage. These silages were opened for fermentation quality and nitrogen components analyses after 1, 4, 8, and 30 days, respectively. Results: The ${\gamma}$-irradiation successfully suppressed microbial activity, indicated by high pH and no apparent increases in fermentation end products in irradiated silages. All nitrogen components, except for peptide-N, increased throughout the ensiling process. Proteolysis less occurred in red clover silages compared with alfalfa silages, indicated by smaller (p<0.05) increment in peptide-N and free amino acid N (FAA-N) during early stage of ensiling. The ${\gamma}$-irradiation treatment increased (p<0.05) peptide-N and FAA-N in alfalfa silage at day 1, whereas not in red clover silage; these two nitrogen components were higher (p<0.05) between day 4 and day 30 in non-irradiated silages than the irradiated silages. The ammonia nitrogen and non-protein nitrogen were highest in non-irradiated alfalfa silage and lowest in irradiated red clover silage after ensiling. Conclusion: The result of this study indicate that red clover and alfalfa are two forages varying in their nitrogen transformation patterns, especially during early stages of ensiling. Microbial activity plays a certain role in the proteolysis and seems little affected by the presence of polyphenol oxidase in red clover compared with alfalfaa.

• 대한예방한의학회지
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• 제26권3호
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• pp.97-108
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• 2022

Objectives : The purpose of this study is to confirm the efficacy and safety of Gongjin-dan and Ssanghwatang for chronic fatigue. Methods : A total of 90 people, between 19 and 65 years old, will be recruited to participate in a randomized, double-blind, and placebo-controlled a clinical trial. Participants in the Gongjin-dan group will take one pill of Gongjin-dan along with three packs of placebo oral liquid Ssanghwa-tang per day for 4 weeks. Participants in the Ssanghwa-tang group will take three packages of liquid Ssanghwa-tang and one placebo Gongjindan pill per day for 4 weeks. In the placebo group, participants will take one pill of placebo Gongjin-dan and three packs of placebo liquid Ssanghwa-tang per day, for 4 weeks. Outcomes will be measured at the baseline, 4^th week, and 6^th week. The primary outcome is the change in the Fatigue Severity Scale (FSS). Secondary outcomes are the change of Multidimensional Fatigue Inventory-20 (MFI-20), Chalder Fatigue Scale (CFQ), Short-Form 36 Health Survey (SF-36), Korean Version of Schedule of Fatigue and Anergy/General Physician (SOFA/GP), Glucose, Lactate, Ammonia, Free Fatty Acid (FAA), d-ROMs&BAP, Selenium, and Cortisol. Results : This trial was approved by the institutional review board of Pusan National University Korean Medicine Hospital (registry number: PNUKHIRB 2021-10-005). Recruitment opened in November 2021 and is supposed to be completed by December 2022. Conclusions : This trial will provide clinical information to determine the efficacy and safety of Gongjindan and Ssanghwa-tang for chronic fatigue.