• 한국식품과학회지
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• 제29권5호
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• pp.827-838
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• 1997

본 연구는 meat flavor 생성에 관계가 있는 아미노산과 당으로 구성된 model system하에서 Maillard 반응을 시키면서 각각의 기질을 단독 또는 혼합하여 반응시켜 끓인 혹은 구운 고기 향미에 가장 근접한 반응기질과 반응 조건을 찾고자 하였다. 반응 중 반응액의 특성은 관능적 특성과 흡광도 및 휘발성 성분을 비교하였고, 검토한 당과 아미노산은 각각 xylose, ribose, glucose, fructose, lactose, maltose, sucrose와 cystine, cysteine HCl, methionine, lysine HCl, glycine이었다. 반응 20시간동안 278 nm와 420 nm의 흡광도 변화로 얻은 반응 속도 상수를 비교한 결과, cysteine HCl을 제외한 4가지 아미노산과 혼합한 5탄당 혼합물이 6탄당이나 이당류와의 혼합물보다 높은 반응 속도 상수를 나타내었다. 또한 반응액의 pH는 반응 8시간 까지 감소하다가 거의 일정한 값을 유지하였고, 반응 속도가 빨랐던 아미노산과 당 혼합물이 더욱 낮은 pH를 나타내었다. 끓인 고기와 구운 고기 향미에 근접하였던 단독 기질로는 $100^{\circ}C$에서 0.2 M cystine에 0.2 M lactose를 20시간, 0.2 M cystine에 0.2 M xylose를 16시간 가열한 반응액이었다. 혼합 기질의 경우는 0.1 M lactose와 0.1 M maltose 또는 0.1 M xylose를 혼합한 혼합당액에 0.2 M cystine을 첨가하여 $100^{\circ}C$에서 20시간 반응한 액이었다. 선정된 4가지 반응액의 GC/MS에 의한 휘발성 향기 성분은 관능적 결과와 유사하였으며, hydrocarbon류 8종, aldehyde류 10종, ketone류 6종, alcohol류 7종, aromatics (benzene)류 2종, ester류 1종, furan류 4종, base류 1종, sulfur compound류 5종을 확인할 수 있었다.

• 한국응용과학기술학회지
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• 제16권3호
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• pp.263-271
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• 1999

We checked the presence of phospholipase $A_2(PLA)_2$ which could split the ester bond at the position 2 in the glycerol backbone of glycerophospholipids, in the cells of hyperthermophiles of Pyrococcus horikoshii and Sulfolobus acidocaldarius. The results obtained are as follows; (1). Pyrococcus horikoshii cells were grown in obligate anaerobic conditions at $95^{\circ}C$ and they needed sulfur as energy source instead of oxygen, while Sulfolobus acidocaldarius species grew well in the aerobic medium (pH 2.5) containing yeast and sucrose at $75^{\circ}C$. (2). Pyrococcus horikoshii cells produced phospholipase $A_2$ in the cell culture media although this species did not show lipase activity at least in the pH range of 1.5 ${\sim}$ 3.5. Sulfolobus acidocaldarius cells produced lipase hydrolyzing triacylglycerols such as triolein, but did not split any kind of phospholipids used as substates. (3). The compound of 1-decanoyl-2-(p-nitrophenylglutaryl) phosphatidylcholine was not suitable for a substrate in this experiment, though frequently used as a subtrate for checking presence of phospholipase $A_2$, for its decomposi-tion in this experiment. The L-${\alpha}$-phosphatidylcholine-${\beta}$-[N-7-nitrobenz-2-oxa-1, 3-diazol]aminohexanoyl-${\gamma}$-hexadecanoyl labelled with a fluorescent material, did not show any migration of acyl chains in the molecule during the reaction with phospholipase $A_2$ under a hot condition. (4). Phospholipase $A_2$ in the cells of Pyrococcus horikoshii, showed the optimum activity at $pH6.7{\sim}7.2$ and $95{\sim}105^{\circ}C$, respectively, and was activated by addition of calcium chloride solution. Andthe phospholipase $A_2$ specifically hydrolyzed glycero-phospholipids such as phosphatidyl choline, phosphatidyl ethanolamine, phosphatidyl serine and phosphatidyl inositol, but could not split phospholipid containing ether bonds in the molecule such as DL -${\alpha}$-phosphatidylcholine-${\beta}$-palmitoyl-${\gamma}$-O-hexadecyl, DL-${\alpha}$-phosphati- dylcholine-${\beta}$- oleoyl-${\gamma}$-O-hexadecyl, DL-phosphatidylcholine-dihexadecyl.

• Journal of Nutrition and Health
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• 제18권4호
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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).

• 한국식품과학회지
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• 제23권4호
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• pp.400-404
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• 1991

Katsuobushi에서 분리한 Aspergillus niger 균주에서 생산한 조효소로부터 정제한 protease의 최적 pH와 온도는 pH 7.2와 $45^{\circ}C$였으며, $pH\;5{\sim}6$ 범위내에서 $40^{\circ}C$ 이하에서 안정하였으며, 금속이온의 영향은 $K^{-}$와 $Fe^{2+}$는 효소활성을 증진시켰고 $Zn^{2},\;Mn^{2}$ 및 $Cd^{3}$등은 효소활성을 저해하였으며, 구성아미노산은 산성아미노산이 22.6%, 염기성아미노산이 13.57%. 중성아미노산이 63.8%였으며, 비극성아미노산, 극성아미노산 및 함황아미노산의 구성비는 각각 39.72%, 23.03% 및 9.35%이었다. 분자량은 42000, 등전점은 pH 5.6이었다.

• 한국식품과학회지
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• 제5권2호
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• pp.119-128
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• 1973

마늘은 강장(强壯), 강정(强精) 식품으로 인정되어 왔으나 그 원인은 아직 미지이다. 여기에는 비타민 E와 밀접한 연관성이 있는 Se 함유아미노산에 기인됨을 가정하고 병아리에 비타민 E, Se 및 마늘을 투여하여 각 장기에 대한 Se 의 함량을 조사하였다. 마늘을 투여한 동물은 Se 및 비타민 E와 Se 투여군보다 Se 함량이 많으며 특히 정소에는 수배이나 축적됨으로 정력제로 될수 있는 요인이 된다고 본다. 쥐에 Se를 $2\;{\mu}g/ml\;(Na_2SeO_3\;Na_2SeO_4)$ 투여하여 성장 및 생존에 미치는 영향을 조사하였다. Se 투여군에서 숫쥐는 성장 및 치사에 영향이 없지만 암쥐는 성장이 훨씬 저하되었다. 본 실험결과 마늘이 정력제에 작용을 하는 것은 Se 함유 아미노산 함량이 풍부함으로 이것이 비타민 E의 작용과 같이 불임(不姙)을 막고 노쇠한 모세혈관을 회복시키는 역할을 상승시켜 주는 것으로 간주된다. 여기서는 Se, 비타민 E, 마늘에 대한 동물의 기능에 영향을 관찰 한 것을 보고 한다.

• The Plant Pathology Journal
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• 제36권5호
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• pp.398-405
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• 2020

Nutrient manipulation is a promising strategy for controlling plant diseases in sustainable agriculture. Although many studies have investigated the relationships between certain elements and plant diseases, few have comprehensively explored how differing mineral nutrition levels might affect plant-fungal pathogen interactions, namely plant susceptibility and resistance. Here, we systematically explored the effects of the seven mineral elements that plants require in the greatest amounts for normal development on the susceptibility of soybean plants (Glycine max) to Fusarium oxysporum infection in controlled greenhouse conditions. Nitrogen (N) negligibly affected plant susceptibility to infection in the range 4 to 24 mM for both tested soybean cultivars. At relatively high concentrations, phosphorus (P) increased plant susceptibility to infection, which led to severely reduced shoot and root dry weights. Potassium (K), calcium (Ca), magnesium (Mg), sulfur (S), and iron (Fe) induced plant resistance to infection as their concentrations were increased. For K and Ca, moderate concentrations had a positive effect on plant resistance to the pathogen, whereas relatively high doses of either element adversely affected plant growth and promoted disease symptoms. Further experiments were conducted, assessing disease suppression by selected combinations of macro-elements and Fe at screened concentrations, i.e., K (9 mM) plus Fe (0.2 mM), and S (4 mM) plus Fe (0.2 mM). The disease index was significantly reduced by the combination of K plus Fe. In conclusion, this systematic investigation of soybean plant responses to F. oxysporum infection provides a solid basis for future environmentally-friendly choices for application in soybean disease control programs.

• 한국수산과학회지
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• 제53권2호
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• pp.165-173
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• 2020

Fish roe is among the most valuable food resources produced by fisheries. Raw fish roe requires processing for conversion into hygienic, marketable, and consumer-acceptable forms. In this study, to investigate the food compositional characteristics of various types of fish roe, we applied vacuum freeze-drying to prepare fish roe concentrates (FRCs) from roe of Alaska pollack Theragra chlcogramma, bastard halibut Paralichythys olivaceus, and skipjack tuna Katsuwonus pelamis. The FRC yield ranged from 22.7 to 26.7 g/100 g roe. The major constituents of FRCs were protein (65.4-79.6%), moisture (2.8-6.2%), lipids (8.5-18.3%), and ash (4.8-7.2%). Potassium, sulfur, sodium, and phosphorus were the major mineral elements of FRCs, and the major amino acids were aspartic acid (9.0-10.4 g/100 g protein), glutamic acid (13.2-14.5 g/100 g protein), lysine (8.4-8.6 g/100 g protein), and leucine (8.3-9.7 g/100 g protein). Vacuum freeze-dried FRCs differed among fish species in terms of amino acid composition and electrophoresis protein band distribution. Therefore, FRCs are an excellent source of protein nutrition and an appropriate protein fortification material in human foods or animal feed.

• BMB Reports
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• 제29권5호
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• pp.429-435
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• 1996

To investigate the structure-antagonistic relationship of the cyclohexapeptide L-659,877, a selective NK-2 tachykinin receptor antagonist, seven analogues were chemically synthesized by a solid phase method. The agonistic and antagonistic activities of the analogues were evaluated by contraction assay using the smooth muscle of guinea pig trachea (GPT) containing the NK-2 receptor. It was shown that the aromatic ring of Phe at position 3 and the sulfur group of Met at position 6 in L-659,877 were essential for binding to the NK-2 receptor. Decrease in antagonistic activity of L-659,877 caused by substituting Leu for Nle at position 5 indicates that the ${\gamma}$ methyl group and side chain length of Leu plays an important role in its antagonistic action. Although the activity was slightly lower than L-659,877, cyclo $[{\beta}Ala^{8}]NKA(4-10)$ (analogue 1) showed potential antagonistic activity for the NK-2 receptor. It was confirmed that the expansion of the ring in L-659,877 by substitution of ${\beta}Ala$ for Gly at position 4 stabilized its conformation monitored by CD spectra. The results suggest that analogue 1 can be used as a new leader compound to design a more powerful, selective, and stable NK-2 receptor antagonist.

• Animal Bioscience
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• 제35권5호
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• pp.721-729
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• 2022

Objective: An experiment was conducted to determine the effects of supplementing graded concentrations of inorganic sulphur (S) without and with folic acid (FA) in maize-soybean meal diets on performance, slaughter and anti-oxidant variables, immune responses and serum protein fractions in broiler chicken. Methods: Inorganic S was supplemented at 0.05%, 0.10%, 0.15%, and 0.20% alone or in combination with FA (4 mg/kg) in basal diet (BD) containing no supplemental methionine (Met) and FA. A control group was fed with the recommended concentration of Met. Each diet was offered to 10 pens of 5 male broiler chicks (Cobb 400) and fed ad libitum from day 1 to 42. Results: The broilers fed the BD had lower body weight gain (BWG), feed efficiency (FE), higher lipid peroxidation (LP), lower activity of glutathione peroxidase (GSHPx), lower lymphocyte proliferation ratio (LPR), and reduced concentrations of total protein, albumin, and globulin in serum. Supplementation of FA and S to the BD improved the BWG (all concentrations of S) and FE (0.20% S) similar to the control group. Similarly, the combination of S and FA significantly improved the concentrations of total protein, albumin, and globulin in serum, reduced the LP and increased the activity of GSHPx and LPR. However, responses in the above parameters were related to the concentration of S in the diet. The slaughter variables and antibody titres against the Newcastle disease were not affected with the treatments. Conclusion: Based on the results, it is concluded that the combination of S (0.2%) and FA (4 mg/kg) improved the BWG and FE, similarly supplementation of these nutrients improved the concentration of protein fractions and reduced the stress (reduced LP and improved GSHPx) variables in serum and improved the cell mediated immune response (LPR) in broilers fed sub-optimal concentrations of Met in diet.

• 한국식품과학회지
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• 제53권4호
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• pp.375-381
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• 2021

본 연구는 다양한 국내에서 재배되는 무의 품종 차이에 따른 이화학적 특성 및 관능적 특성을 관찰하였고, 이를 위해 당도, 염도, pH, 전자혀 및 전자코 분석을 진행하였다. 네 가지 품종 중 맛동무가 가장 높은 당도를 나타내었고, 만사형통무가 가장 낮은 당도를 나타내었다. 염도의 경우 맛동무가 가장 높은 염도를 나타내었고, 맛동무를 제외한 나머지 시료들의 경우 품종 간 차이가 발생하지 않앗다. pH의 경우 서호무가 가장 높은 pH를 나타내었고, 청정고원무와 만사형통무가 가장 낮은 pH를 나타내는 것을 확인하였다. 전자혀 센서를 통해 확인된 맛 성분의 결과는 서호무와 청정고원무가 신맛과 관련된 센서값이 대체로 높은 것을 확인할 수 있었고, 만사형통무와 맛동무가 대체로 낮은 것을 확인할 수 있었다. 반면 짠맛과 관련된 센서의 결과는 만사형통무와 맛동무가 높은 센서 값을 나타내었고, 서호무와 청정고원무가 대체로 낮은 센서 값을 나타내었다. 감칠맛과 관련된 센서는 서호무와 청정고원무가 대체로 높은 값을 나타내었고, 만사형통무와 맛동무가 대체로 낮은 값을 나타내었다. 그리고 단맛과 관련된 센서 결과는 서호무와 청정고원무가 낮은 센서 값을 나타내었고, 만사형통무와 맛동무가 낮은 센서 값을 나타내었다. 그리고 전자코를 이용하여 휘발성 화합물을 분석하였고, 그 결과 모든 품종의 무에서 휘발성 함황화합물인 methanthiol이 가장 높은 함량을 나타내었다. 이화학적 특성 및 관능적 특성을 이용하여 시료들의 패턴을 주성분 분석을 통해 확인하였고, 그 결과 청정고원무는 휘발성 aldehydes류, acids와 esters류, 그리고 alcohols류 화합물이 variables로 확인되었다. 만사형통무는 전자혀의 짠맛과 관련된 센서, 단맛과 관련된 센서, 그리고 휘발성 hydrocarbons류가 variables로 확인되었다. 맛동무는 염도의 결과에 의해 다른 시료들과 구분되는 위치를 나타내었고, 서호무는 휘발성 ketones류 화합물, 신맛과 관련된 센서, 감칠맛과 관련된 센서, 그리고 pH가 variables로 확인되었다. 앞선 이화학적 특성 및 관능적 특성의 결과를 이용하여 시료 간 차이를 군집분석을 통해 확인하였고, 만사형통무와 맛동무가 시료 간 상대적으로 낮은 차이도를 나타내었다. 그리고 서호무와 청정고원무가 시료 간 상대적으로 낮은 차이도를 나타내었다. 본 연구의 결과는 국내에서 재배되는 품종별 무의 이화학적 특성과 관능적 특성에 대한 기초 자료로써 검토 및 활용이 가능할 것으로 판단된다.