• 한국수산과학회지
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• 제7권1호
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• pp.37-40
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• 1974

수획기(1973년 9월$\~$1974년 4월) 중, 참굴의 생패를 채취하고 자숙하여서 얻은 자즙의 식품영양학적가치를 평가하기 위하여 화학포성의 월별 변화를 분석한 결과는 다음과 같다. (1) 조단백태 질소의 양은 1월을 전후하여 약간 감소하였으나, 그 이후는 계속 증가하는 경향이었으며, 이 점은 비단백태 질소에서도 같은 결과이었다. (2) 아미노태 질소는 4월까지 계속 증가하였으며, 특히 2월 이후는 급격히 증가하였다. (3) 총당은 그 대부분이 글리코겐으로 이루어져 있음을 알 수 있었고, 글리코겐은 아미노태 질소의 함량변화와 비슷한 경향으로서 4월까지 계속 증가하였다. (4) 자즙중의 조단백질과 총당의 함량변화는 수분함량과는 역의 상관관계를 보였다.

• 생태와환경
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• 제51권1호
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• pp.96-104
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• 2018

안정동위원소비는 전 세계적으로 수생태 환경 연구에서 매우 활발하게 적용되고 있는 분야로써, 국내에서도 2000년대 이후 담수 및 연안 생태계의 먹이망 구조 연구 등 다양한 연구에서 활용되고 있다. 최근에는 기존의 총 조직내의 안정동위원소 분석기법의 한계점을 인지하고 보완하기 위한 방안으로 아미노산의 질소 안정동위원소 분석 기법이 개발되었으며, 이를 활용한 다양한 연구 사례들이 보고됨에 따라 수생태 연구의 활용범위가 급격히 확대되고 있다. 아미노산의 질소 안정동위원소 분석기법의 기술적인 접근성의 한계에 의해 현재까지 국내에서 수생태계 연구를 위해 아미노산의 질소 안정동위원소비를 활용한 연구는 제한적인 실정이지만, 국내 다양한 하천 및 호수 그리고 연안의 환경 변화 특성을 고려할 때, 향후 수생태 환경연구에 있어 그 유용성과 활용 가치가 대단히 높을 것으로 전망된다.

• 한국식품저장유통학회지
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• 제8권4호
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• pp.449-455
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• 2001

키위와 무를 첨가하여 42$^{\circ}C$에서 72시간동안 발효시킨 검정콩 청국장의 pH, 총산, 환원당, 질소화합물 및 무기질 함량을 조사하였다. 검정콩 청국장의 발효중 pH는 증가하였고, 총산은 감소하였으며, 키위를 첨가한 검정콩 청국장을 제외한 시료구 모두 24시간 이후로 급격한 변화를 나타내었다. 환원당은 24시간을 전후하여 증가하다가 감소하였고, 검정콩 청국장은 가장 함량이 많았으며, 나머지 청국장은 비슷하였다. 아미노태 질소는 발효 24시간 이후부터 급격히 증가하였으며, 키위와 무를 첨가하므로 검정콩 단백질의 분해율을 증진시켜 대두 청국장과 비슷한 함량을 나타내었다. 암모니아태 질소는 72시간 이상 발효할 때에는 검정콩 청국장이 대두 청국장에 비하여 적은 함량을 나타내었다. 무기질은 K가 가장 많았고, 다음으로 P > Mg > Ca순으로 많았으며, 대체로 검정콩 청국장류가 대두 청국장보다 비슷하거나 약간 많았다.

• Journal of Microbiology and Biotechnology
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• 제31권5호
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• pp.659-666
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• 2021

After Candida albicans, Candida glabrata is one of the most common fungal species associated with candidemia in nosocomial infections. Rapid acquisition of nutrients from the host is important for the survival of pathogens which possess the metabolic flexibility to assimilate different carbon and nitrogen compounds. In Saccharomyces cerevisiae, nitrogen assimilation is controlled through a mechanism known as Nitrogen Catabolite Repression (NCR). NCR is coordinated by the action of four GATA factors; two positive regulators, Gat1 and Gln3, and two negative regulators, Gzf3 and Dal80. A mechanism in C. glabrata similar to NCR in S. cerevisiae has not been broadly studied. We previously showed that in C. glabrata, Gln3, and not Gat1, has a major role in nitrogen assimilation as opposed to what has been observed in S. cerevisiae in which both factors regulate NCR-sensitive genes. Here, we expand the knowledge about the role of Gln3 from C. glabrata through the transcriptional analysis of BG14 and gln3Δ strains. Approximately, 53.5% of the detected genes were differentially expressed (DEG). From these DEG, amino acid metabolism and ABC transporters were two of the most enriched KEGG categories in our analysis (Up-DEG and Down-DEG, respectively). Furthermore, a positive role of Gln3 in AAA assimilation was described, as was its role in the transcriptional regulation of ARO8. Finally, an unexpected negative role of Gln3 in the gene regulation of ABC transporters CDR1 and CDR2 and its associated transcriptional regulator PDR1 was found. This observation was confirmed by a decreased susceptibility of the gln3Δ strain to fluconazole.

• Journal of Ginseng Research
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• 제9권1호
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• pp.95-103
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• 1985

The concentrated red ginseng extract (RG-EXT) was prepared by extracting the ginseng tails with 0-90% ethanol solution at 70-100$^{\circ}C$ and analyzed for amino acids composition and other nitrogeneous fractions. The results showed that nonprotein fraction was more than 90% of the total N-compounds and 17 free amino acids were identified by High Performance Liquid Chromatography. Maximum and minimum N-compounds or total free amino acids were recovered in RG-EXT with 50% and 90% ethanol, respectively. An increase in ethanol concentration resulted a significant change in free amino acid composition while extraction temperature caused a little gradual decrease in water soluble nonprotein and total nitrogen fractions.

• Bulletin of the Korean Chemical Society
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• 제11권1호
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• pp.22-25
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• 1990

The condensation of 1-amino-1,2-dihydro-3,6-pyridazinedione (1) and 2-amino-2,3-dihydro-1,4-phthalazinedione (2) with mesityl oxide or 3-penten-2-one in acetic acid-ethanol (1:1) gave 3,4,6,9-tetrahydro-6,9-dioxopyridazino[1,2-a][1,2, 3]triazines (9,11) and 3,4,6,11-tetrahydro-6,11-dioxo[1,2,3]triazino[1,2- b]phthalazines (10,12), respectively. The condensation of 1 and 2 with crotonaldehyde, cinnamaldehyde or acrylaldehyde under the same reaction condition gave only N-alkylidene derivatlives (3-8). When the N-alkylidene derivatives isolated from the reaction of 1 and 2 with crotonaldehyde and cinnamaldehyde (3-6) were refluxed in acetic acid, the corresponding heterocyclic compounds (13-16) were obtained.

• Bulletin of the Korean Chemical Society
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• 제9권6호
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• pp.359-362
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• 1988

The condensation of 1-amino-1,2-dihydro-3,6-pyridazinedione (1) and 2-amino-2,3-dihydro-1,4-phthalazinedione (2) with 1,3-diketones or 1,3-dialdehydes in polyphosphoric acid gave 6,9-dihydro-6,9-dioxopyridazino [1,2-a][1,2,3]triazines (3-6) and 6,11-dihydro-6,11-dioxo[1,2,3]triazino[1,2-b]phtha lazines (7-10), respectively. The condensation of 2 with 2,4-pentanedione in acetic acid gave N-alkylidene intermediate (11), which was cyclized to 9 by treatment with polyphosphoric acid.

• 한국식품영양학회지
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• 제24권4호
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• pp.761-769
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• 2011

The objective of this study was to investigate the physicochemical properties of Korean traditional soy sauces made with soybeans sown in different producing regions(Hadong, Paju) and in different seeding periods(late-May, mid-June, late-June). The total acidity, salt content, chromaticity, browning, amino nitrogen content and the reducing sugar content of the soy sauce samples were compared. It was found that the total acidity level and the amino nitrogen contents were significantly lower in the soy sauce made with mid-June soybeans, and that these properties increased as the sauce aged. Salt content increased with the aging period regardless of the region of production. The reducing sugar content of Paju soy sauce was the highest in late -June, and for the Hadong region, highest in late-May. The sauce made with Hadong soy beans showed an increase in reducing sugar content positively correlated with the aging period. Reducing sugar content in the samples of Paju soy sauce decreased up to 60 days of aging, but increased after this point. In Paju soy sauce, the brightness(L value) was significantly higher in mid-June, and the Hadong variant it was higher in late -May. The yellowness(b value) at the beginning of the aging process was high in late -June for Hadong soy sauce, but overall it was higher in the mid-June period. The more matured soy sauce samples were darker and showed both higher a and b values. The browning was the lowest in the mid -June regardless of the regions and it increased with the aging period regardless of the production regions. The salt, amino nitrogen contents, browning and yellowness showed significant correlations among the samples. In conclusion, the seeding period of soy beans may affect the characteristics of produced soy sauce alongside the aging conditions.

• Asian-Australasian Journal of Animal Sciences
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• 제29권5호
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• pp.689-694
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• 2016

The objective of the current study was to evaluate the effect of supplementation of either L-methionine (L-Met) or DL-methionine (DL-Met) to diets of starter pigs on nitrogen (N) balance, metabolism, and serum amino acid profile. Eighteen crossbred ($Duroc{\times}Landrace{\times}Yorkshire$) barrows weighing $15.45{\pm}0.88kg$ were randomly allotted to 1 of 3 diets with 6 pigs per treatment. The diets included a basal diet (Met-deficient diet) containing 0.24% standardized ileal digestibility Met with all other essential nutrients meeting the pig's requirements. The other two diets were produced by supplementing the basal diet with 0.12% DL-Met or L-Met. The experiment lasted for 18 days, consisting of a 13-day adaptation period to the diets followed by a 5-day experimental period. Pigs were fed ad libitum and free access to water throughout the experiment. Results showed that the supplementation of either L-Met or DL-Met improved N retention, and serum methionine concentration, and decreased N excretion compared with basal diet (p<0.01). The N retention of pigs fed diets supplemented with the same inclusion levels of DL-Met or L-Met were not different (p>0.05). In conclusion, on equimolar basis DL-Met and L-Met are equally bioavailable as Met sources for starter pigs.

• Asian-Australasian Journal of Animal Sciences
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• 제11권1호
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• pp.21-29
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• 1998

Four feeding trials with 260 pigs were conducted to evaluate the effects of supplementing the diet with different amino acids on growth performance and blood metabolites for weanling, growing and finishing pigs. One hundred twenty weanling pigs (Exp. 1, BW 8 kg), eighty growing pigs (Exp. 2. BW 20 kg), thirty growing pigs (Exp. 3, BW 29 kg) and thirty finishing pigs (Exp. 4, BW 50 kg) were randomly allotted to different dietary treatments according to sex and body weight. Pigs weight and feed consumption were measured at initiation and termination of each trial with 4 weeks. At the end of trial, blood samples from three pigs selected in each pen (Exp. 1) and each pig (Exp. 2) were obtained to determine the level of blood urea nitrogen, glucose, insulin and cortisol in the serum. In Exp. 1, pigs fed diet supplemented both with lysine and methionine had the best feed conversion ratio (p < 0.05), but no significant differences (p > 0.05) were observed in ADG and ADFI. Pigs receiving control diet obtained the obtained the optimal ADG (p < 0.05), ADFI (p < 0.05) and F/G for the whole period. No differences were detected in serum glucose, insulin and cortisol concentrations. In Exp. 2, pigs receiving the control diet exhibited the lowest serum urea nitrogen (p < 0.05), ADG, F/G and serum insulin concentration increased linearly (p < 0.05) with the inclusion of lysine, methionine, threonine and tryptophan in diets. No significant differences (p > 0.05) were detected for glucose and cortisol content in pigs serum among dietary treatments. In Exp. 3 and 4, pigs growth rate increased linearly (p < 0.01), and feed conversion efficiency was also improves by addition of lysine, methionine, threonine and tryptophan. In conclusion, pigs fed diets supplemented with lysine, methionine, threonine and tryptophan together obtained optimal growth performance in growing and finishing periods.