북한 경제의 개방화정책과 외채문제

유인덕 북한연구소 1986 北韓 Vol.- No.172

肉鷄(Broiler chicken) 加工에 關한 硏究(第 1 報) 肉鷄 各組織의 염수용성 단백의 유화력

柳寅德 忠州大學校 1981 한국교통대학교 논문집 Vol.14 No.2

This study was designed to determine certain of the physiochemical characteristics of various Broiler chicken meat tissues which would determine their usefulness in various Broiler chicken meat products. The measurements made included total protein, total moisture, total ether extractables, salt soluble protein, and emulsifyingcapacity of salt -soluble protein, and total collagen, Results obtained were follows: 1. Total protein and salt soluble protein was found in significantly greater amounts in light muscle tissue than in dark muscle tissue. This indicates that light meat would have a greater total amount of emulsifying potential than dark meat. 2. Skin tissue is the least desirable tissue in emulsification properties. 3. Gizzard, heart tissue is in intermediate desirable tissue in emulsification properties. 4. collagen can be detrimental to the process of making Broiler chicken meat emulsion because of the inability of collagen to dissolve and form stabilizing membranes necessary for emulsion formation.

微生物이 生産하는 凝乳酵素에 關한 硏究

趙載敏,柳寅德 忠州大學校 1987 한국교통대학교 논문집 Vol.20 No.2

62 strains were isolated from 114 soil samples which were collected on the various places of KOREA. 18 strains of screened microorganisms showed the formation ability of Milk-clotting. One strain that had presented higher value in the ratio of Milk-clotting activity to proteolytic activity of Milk-clotting enzymes produced from this 18 strains was selected and identified as a number of the genus mucor sp. When it is cultured on wheat bran, the optimum experimental conditions for production of Milk-clotting enzyme were investigated and the results were obtained as follows. Amount of distilled water which added to the solid media was 100% to the weight of wheat bran. When Macllvaine butter soln. (PH4.5) instead of distilled water was added to the wheat bran medium, enzyme production was increased effectively. The optimum temperature and incubated period for Milk-clotting enzyme formation were 30℃ and 72 hrs. respectively. The important nutrition-sources for the formation of Milk-clotting enzyme were 2% glucose as carbon source, 0.5%(NH₄)₂SO₄as nitrogen source, 0.1%MnSO₄as metal salt. When the mixed Maccllvaine butter solns was added to wheat bran medium after dissolving the important nutrition-sources in Macllvaine butter soln.(PH4.5) respectively, Milk-clotting enyme production was added to wheat bran. In this experiments, Macllvaine buffer soln. (PH.4.5) was vitally important for increasing enzyme production. Milk-clotting enzyme was produced in high yield on solid wheat bran media by an isolatec strain and the produced enzyme was extracted with distilled water and precipitated by salting out with Ammonium sulfate. Some enzymological properties of the crude enzyme (CMR) were studied and compared with those of cal-rennet(CR) and Mucor-miehei-rennet (MMR). Amonium sulfate of various precipitation agents for enzyme production was so effected and the recovery of Milk-clatting activity was 98% at Ammonium sulfate 0.66 saturation CMR was protease with an optimum PH of 3.0 for casein digestion. Proteolytic activity of CMR was more increased in 10% reconstituted skim milk (SK) containing 1/1000 M-CaCl₂than in SK containing 1/100 M-CaCl₂and Milk-clotting activity of CMR was so effected byincreasing ca ion concentration in SK. The MCA/PA ratio of CMR was showed lower value than the MCA/PA ratio of MMR or CR. The optimum temperature for Milk-clotting of CMR was around 55℃ and 45℃ on a substrate of SK containing 1/100 M-CaCl₂and 1/1000 M-cacl₂respectively and the stable temperature for Milk-clotting activity of CMR against heat treatment was 40℃. This enzyme was rather stable between PH.2.5 and 6.5 and was inbibited with Hg?? or Cu??.

Yeast Carboxypeptidase에 관한 연구

柳寅德 忠州大學校 1984 한국교통대학교 논문집 Vol.17 No.2

This study was undertaken to investigate the purification of carboxypeptidase from Sacch. cerevisiae, its physical and chemical properties, and its application to COOH-terminal analysis of peptide and protein Results obtained were follows: 1. Chromatogrographically purified, electrophoretically honogeneous carboxypeptidase, free of proteinasseactivity was obtained froms cerevisiae. 2. The molecular weight of the yeast carboxypeptidase estimated by gel electophoresis was 61,000 by comparison with standard protein and consists of a single polypeptide chain 442 residues with 16 residues of Glucosamine in the carbohydrate moiety. 3. The COOH-termianl sequence of this eczyme is-ASP-Ser-Thr-Le-u and has a hexose content of 15.0% 4. The proteinase action which might hydrolyze in ternal bonds inaprotein to yield large peptide fragments is absent in the preparation of yeast carboxypeptidase. 5. In oder to test the use of yeast carboxypeptidase for sequence determination, the rates of release of aminoacids from RCM-Rnase by the enzyme were followed quantitatively. 6. The yeast carboxypeptidase retains activity in 6M-urea and can be used for the study of proteins that may have inaccessible COOH-termini in the aqueous soln.

Lactobacillus가 생산하는 Bacteriocin의 검출과 활성

柳寅德 忠州大學校 1995 한국교통대학교 논문집 Vol.30 No.2

A total of 52 strains of Lactobacillus acidophilus were examined for production of bacteriocins. A majority(63%) demonstrated inhibitory activity against all members of a four-species grouping of Lactobacillus leichmannii, Lactobacillus brlgaricus, Lactobacillus helveticus, and Lactobacillus lactis. Four L.acidophilus strains with this activity also inhibited Streptococcus faecalis and Lactobacillus fermentum, suggesting a second system of antagonism. Under conditions eliminating the effects of organic acids and hydrogen peroxide, no inhibition of other gram-positive or-negative genera was demonstrated by L. acidophilus. The agent produced by L. acidophilus N2 and responsible for inhibition of L. leichmannii, L. bulgaricus, L. helveticus, and L. lactis was investigated, Ultrafiltration studies indicated a molecular weight of approximately 100,000 for the crude inhibitor, The agent was sensitive to proteolytic enzymes and retained full activity after 60 min at 100℃ (pH5). Activity against sensitive cells was bactericidal but nit bacteriolytic. These characteristics indentified the inhibitory agent as bacteriocin, desiganated lactacin B. Examination of strains of L. acidophilus within the six homology groupings of Johnson et al. (Int, J, Syst, Bacteriol. 30:53~68, 1980) demonstrated that production of the bacteriocin lactacin B could not be used in classification of neotype L. acidophilus strains. However, the usefulness of empolying sensitivity to lactacin B in classification of dairy lactobacilli is suggested.

간장제조시 염수발효중 내삼투압성 젖산균과 효모사이의 길항작용

柳寅德 忠州大學校 1996 한국교통대학교 논문집 Vol.31 No.2

The purpose of the present investigation was to study the nature of the interaction between the osmophilic lactic acid bacteria and yeasts in brine fermentation of soy sauce. It was recognized that osmophilic soy sauce yeasts such as Saccharomyces rouxii inhibited by a metabolite produced (Pediococcus halophilus) in brine fermentation of soy sauce. The primary inhibitory was considered to be acetic acid although lactic acid was slightly inhibitory.

I.R. Spectrophotometry 에 의한 냉장 肉鷄의 變敗에 關한 硏究

柳寅德 忠州大學校 1980 한국교통대학교 논문집 Vol.13 No.1

The purpose of this study was to determine, by the use of infrared spectrophotometry, if and to what extent changes in solvent extractable substances on the skin surface were detectable on chicken carcasses, and if this changes could be related to time in refrigerated storage or to bacterial numbers as determined by swab techniques. Results obtained are follows: 1. The 6.1μ peak height (as a percentage of the reference peak) exhibited a regular increase during refrigerated storage. 2. The magnitude of the change is greater in ether than in carbon tetra chloride, indicating the absorbing substances are extracted more completely in Ether. 3. Peak, at 6.1μ shows a pattern of change similar to that of counts of total aerobic bacteria on the skin. 4. The adsorbing substances at 6.1μ were not identified.

Lactobacillus plantarum 세포의 Choline특성

柳寅德 忠州大學校 1999 한국교통대학교 논문집 Vol.34 No.2

The nature of choline in Lactobacillus plantarum grown on the Trypticase Soybroth and semisynthetic medium was investigated. Choline accumulated within cells when L. plantarum was grown on a TSB, whereas when the same organism was grown on a semisynthetic medium, no choline accumulation was oberved. Only the addition of choline O-sulfate resulted in the accumulation of choline in cells grown on semisynthetic medium to the extent seen in cells grown on TSB medium. The choline of TSB-grown cells is shown to be non-lipoidal and to occur in the cells as free choline, choline O-sulfate and choline O-phosphate. No choline was detected in the cell wall.

Lactobacillus casei와 Kluyveromyces fragilis에 의한 豆乳의 젖산 醱酵中 과당류 代謝의 相互作用

柳寅德 충주대 산업과학기술연구소 1994 産業科學論文集 Vol.2 No.-

The mechanism involved in the enhanced growth and lactic acid production of Lactobacillus casei IFO 3012 mixed with Kluyveromyces fragilis(KFCC 35458) in Soymilk was investigated. K. fragilis was grown in soymilk and in the resulting culture filtrate was added to the culture of L. Casei and the effect on the growth and acid production was observed. It was found that K, frogilis produced enzymes which can convert sucrose, raffinose and stachyose, common sugars of soymilk, into glucose and fructose which can be fermented by L. cosei and in turn stimulated growth and acid production of the latter.

科學敎育에 關한 調査實例

兪仁德 이화여자대학교 사범대학 과학교육과 1966 과학교육 Vol.2 No.-