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Proteolytic Digestion of Boiled Pork by Soused Shrimp (새우젓 중의 단백질 분해효소에 대한 연구)

  • 박길홍
    • Journal of Nutrition and Health
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    • v.19 no.6
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    • pp.363-373
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    • 1986
  • This study was devised to elucidate whether soused shrimp exhibits a digestive action on boiled pork meats. and the mechanism by which sousing with a high concentration of sodium chloride preserves nutrients in foods for a prolonged pe\ulcornerriod. Protease was isolated from soused shrimp using a combination of ammonium sulfate fractionation. DEAE - cellulose ion exchange chromatography and gel filtra\ulcornertion. The isolated protease had specific activity of 1.560 units. 210 purification fo\ulcornerld with an yield of 38%. Its optimum pH and temperature were 8.0 and $43^{\circ}C$ respectively. The molecular weight of the enzyme was 35.000. The Km value of the enzyme for casein was 1.6 x $10^{-6}$ M The e=yme required the presence of cu\ulcornerpric ion to exhibit its full activity. Eighty eight percent of the enzyme activity was in\ulcornerhibited by 3.5M NaCI showing a reversibly linear decrease of the enzyme activity as NaCI concentration increased. The nature of the inhibition by NaCl was rever\ulcornersible and noncompetitive. The protease activity in soused shrimp was well preser\ulcornerved with the elapse of time at least in part due to NaCI induced suppression of autodigestion. The enzyme was denatured by acid easily. i.e. 1% of the original activity remained after staying at pH 2 for 10 minutes. which is within the norm\ulcorneral range of pH of the human stomach. Soused shrimp was observed to be one of those containing the highest protease activity compared with the other soused foo\ulcornerds such as soused oyster. squid. clam. and Pollack intestine with respect to spec\ulcornerific activities of dialized 1:4 whole homogenates(w/v) in 5 mM sodium phospha\ulcornerte - 2.4 mM j3 - mercaptoethanol buffer. pH 8.0. Casein and boiled meats including pork, beef, and chicken appeared to be the good substrates for the protease. Casein was the best. Therefore. the ingestion of boiled meats including pork together with soused sh\ulcornerrimp would help digestion of boiled pork in human not only by increasing appe\ulcornertite also by the direct proteolytic digestion of boiled meats by soused shrimp to\ulcorner some extent. And a high concentration of sodium chloride inhibited the protease activity reversibly in a remarkable degree, which ensued in a significant retardat\ulcornerion of autodigestion of protein in foods by proteases, and hereby contributed to the preservation of foods for an extended period.

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Effect of Gel Nail Remover Liquid on Nail According to Acetone Concentrationon (아세톤 농도에 따른 젤네일 리무버액이 손톱에 미치는 영향)

  • Kim, Young-Hee;Li, Shun-Hua
    • Journal of the Korean Applied Science and Technology
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    • v.36 no.1
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    • pp.248-257
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    • 2019
  • On this study, we have observed the change of the gel nail morphology as the time elapse and measured the surface roughness/volume, moisture content/purcutaneous moisture vaporizing amount of the nail surface before gel nail treatment and after gel nail removing of the 100%acetone remover, 5%acetone remover and 0%acetone remover and the avocado non acetone remover for the comparison of the effect on the nail surface and the degree of the removing of the gel nail of the removers as the acetone contents. The removing ability were the order of 100%acetone remover, avocado non acetone remover, 5%acetone remover and the 0%acetone remover. There were no statistical significance difference in the nail surface roughness comparision before and after gel nail removing in 5%acetone, 0%acetone and avocado non acetone, and there was no statistical significance difference in the nail surface volume comparision before and after gel nail removing in 0%acetone. We measured the moisture content of the nail surface and the purcutaneous moisture vaporizing amount before gel nail treatment and after gel nail removing, resulted that, the decrease of the moisture content of the nail surface after removing the gel nail is the minimun and the increase of the purcutaneous moisture vaporizing amount of the nail surface after removing the gel nail is the minimun at the case of 0%acetone. In conclusion, 5%acetone remover and 0%acetone remover is possible to use as the gel nail remover and they had revealed that there was the least harmful effect on the nail. We hope that this study is utilized to the development of the non acetone remover and the basic research of the nail beauty industry.

Effects of Additives on the Quality Improvement of Minced Ginger (Zingiber officinale Roscoe) During Storage (생강(Zingiber officinale Roscoe) 다대기의 저장 중 품질개선을 위한 첨가물 효과)

  • Lee, Myung-Hee;Lee, Kyoung-Hae;Cho, Chang-Won;Kim, Kyung-Tack
    • Journal of Food Hygiene and Safety
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    • v.25 no.1
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    • pp.59-64
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    • 2010
  • The effects of vinegar, alcohol and ascorbic acid on the color, microorganism, sensory properties and flavor pattern of minced ginger (MG) were investigated during storage for 28 days at $30^{\circ}C$. The values of L (lightness), a (redness) and b (yellowness) of the control (T-0) and all the treatments changed slightly at the initial stage of storage, however the elapse of time accelerated the changes. The total bacterial counts of T-0 showed $5.37{\times}10^7\;CFU/g$ at the initial stage, but the MG-treatments decreased the bacteria above 4 log compared to T-0. It was showed that the additives were effective for inhibition of the growth of microorganism. Sensory properties of flavor intensity test showed no significant difference between T-0 and MG-treatments (p < 0.05). The result of volatile flavor contents of electronic nose analyzer (ENZ) showed that MG-treatments (T-I, T-II, T-III) was recognized stronger than non-treatment at the initial stage, but the change of flavor compound were stabilized soon regardless of type or quantity of additives during total storage period at $30^{\circ}C$.

Effects of Spice Addition on the Inhibition of Bacterial Growth in Ground Chicken Meat (향신료 첨가에 의한 닭고기 분쇄육에서의 미생물 증식 억제 효과)

  • Seyun Jeong;Yong-Suk Kim
    • Journal of Food Hygiene and Safety
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    • v.38 no.1
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    • pp.19-25
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    • 2023
  • Addition of spice for inhibition of bacterial growth in ground chicken meat was investigated. The ground chicken meat approximately contained 72.98±0.15% moisture, 23.37±0.46% crude protein, 1.00±0.03% crude fat, and 1.90±0.03% ashes. Addition of rosemary showed the maximum bacterial inhibition, followed by garlic and mustard. The inhibitory effect increased with the addition of a greater quantity of spices. The optimal added concentration of spices for inhibition of total viable cell and proliferation of Escherichia coli in ground chicken meat was 2%, 4%, and 1.2% for rosemary, garlic, and mustard, respectively. The growth inhibition of total viable cells and E. coli differed during storage period for MixA (97.4%) > rosemary (96.9%) > MixB (96.3%) > garlic (53.7%) > mustard (33.3%). The addition of sterilized garlic to ground chicken meat showed that the total viable cells was low at 2.6-3.0 log CFU/g on the 0-day and 2.4-3.2 log CFU/g on the 9-day, and the number decreased as the storage lengthened. Non-sterilized garlic treatment showed a higher number of total viable cells than the control group, and this increased with elapse of storage time. The number of E. coli, was low at 0.4-1.0 log CFU/g on the 0-day and 0.5-1.5 log CFU/g on the 9-day for the sterilized group, and the change during the storage showed a similar trend for the total viable cells. In conclusion, the microbial safety of ground chicken meat products was improved by various mixed applications of rosemary, garlic, and mustard.

POLYMERIZATION SHRINKAGE OF COMPOSITE RESIN USING DOUBLE CURING UNIT SYSTEM (Double curing unit system을 이용한 복합 레진의 광중합 수축에 관한 연구)

  • Han, Mi-Ran;Kim, Jong-Soo;Yoo, Seung-Hoon
    • Journal of the korean academy of Pediatric Dentistry
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    • v.36 no.2
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    • pp.189-198
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    • 2009
  • As a part of an effort to minimize the polymerization shrinkage which is considered to be a major cause of failed bonds to tooth, newly designed 'Double LED system' was tested in the present study. Analyses were performed on the pattern of micro-leakage and the changes of strain which have occurred during the polymerization process. The results can be summarized as follows: 1. In the strain change, dramatic increase was observed with initiation of polymerization which was followed by subsequent gradual decrease with elapse of time in both the single LED system and double LED system. 2. The single LED system were shown to develop and maintain the maximum stress more than double LED system(p<0.05). 3. Less micro-leakage was found in the double LED system than in the single LED system(p<0.05). From the above-mentioned results, the double LED system can be a very useful tool in a sense of reducing polymerization shrinkage when compared to the single LED system. However, practical problems such as size of curing unit and its application method with its light intensity should be solved before its clinical application.

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Study on the survival rate of fishes escaped from trawl net (트롤 탈출어류의 생존율 연구)

  • Cho, Sam-Kwang;An, Heui-Chun;Shin, Jong-Keun;Yang, Yong-Su;Park, Chang-Doo;Lee, Ju-Hee
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.42 no.2
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    • pp.69-77
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    • 2006
  • The aim of this study was to develope a fishing technology for fisheries management for improving the survival rate of young fishes escaped from trawl net. Sea experiments were carried out to investigate the survival rate of the fishes in off Geomun island and Korean southern sea. Cover-net fish cage was designed and manufactured to collect fishes escaped from COD(codend) and TED(trawl escapement device). Fish cage was installed in a shallow site where scuba diver can observe the surviving fishes after separating the cage from trawl net. Most of fishes except horse mackerel(Trachurus japonicus) and mackerel(Scomber japonicus) could escaped through TED(bar space 35mm) easier than COD(mesh size 54mm). Especially, escapement rate of redlip croaker(Pseudosciaena polyactis) escaped from TED was the highest as 73.9%. Survival rate of horse mackerel(Trachurus japonicus) escaped from TED was 85.5% at the point of 96 hours over, while the survival rate for COD showed a rapid decrease according to the time elapse as 85.0% at the point of 24 hours, 76.4% for 48 hours, 62.7% for 72 hours and 56.1% for 96 hours. Over 90% of red seabream(Pagrus major) and rock bream(Oplegnathus fasciatus) escaped from TED were survived 96 hours over and the survival rate of those fishes were excellent compared with the other fish species. All korean pomfret(Pampus echinogaster) escaped from both COD and TED were died within 48 hours. Most of redlip croaker(Pseudosciaena polyactis) were also died within 12 hours because of the weak physiological characteristics by water pressure change. Survival rate of fishes like as horse mackerel(Trachurus japonicus) having hard skin was high while it was low for the fishes like as squid(Todarodes pacificus) and hair-tail(Trichiurus lepturus) having soft skin. We could know that there were big differences in the survival rate offish species escaped from trawl net.

Study on Decay Characteristics Change of Spent Fuel Materials by DUPIC Fuel Cycle (DUPIC핵연료주기에 의한 사용 후 경수로핵연료의 방사선적 특성변화 분석)

  • Choi, Jong-Won;Ko, Won-Il;Lee, Jae-Sol;Park, Hyun-Soo
    • Journal of Radiation Protection and Research
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    • v.21 no.1
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    • pp.27-39
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    • 1996
  • The change in spent fuel characteristics by DUPIC fuel cycle(burnup of spent PWR fuel again in CANDU) is examined with time elapse since discharge. Major characteristics examined include isotopic concentration, radioactivity, decay heat radiotoxicity and radiation source-term of spent fuel material, which is existing in a type of spent PWR and DUPIC fuel. Behaviors of major nuclides contributing to such changes are also analyzed in terms of radionuclide concentration. From the analysis, the change in radionuclide concentration by DUPIC shows approximately 2% decrease in actinides concentration and 20% increase in fission products concentration. Radioactivity and decay heat of spent DUPIC fuel does not depend upon radionuclides concentrations, which is a unique in sence of general characteristics of spent fuel. In terms of gamma spectrum, spent DUPIC fuel shows lower values than that of spent PWR fuel by 40 to 50% in the range of $0.01{\sim}0.575$ MeV but much higher over 3.5MeV. Neutron Intensities of both spent fuels are mainly determined by $({\alpha},\;n)$ reaction and spontaneous fission reaction of actinides. Of them, especially, the spontaneous fission reaction Is a major neutron source-term, which causes that neutron intensities of spent DUPIC fuel $having{\sim}3.3$ times higher Cm-244 concentration are ${\sim}4$ times higher than that of spent PWR fuel.

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Effect of Metal Ions on the Oxidation of Soybean Oil and Its Fried Noodle (각종(各種) 금속(金屬) 이온이 대두유(大豆油)및 그 튀김 면(麵)의 산패(酸敗)에 미치는 영향에 대(對)하여)

  • Choe, Myen;Kim, Tae-Woong;Lee, Yang-Hee
    • Korean Journal of Food Science and Technology
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    • v.9 no.2
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    • pp.157-164
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    • 1977
  • In the present study, the proxidant effect of ferrous and cupric chlorides which added to soybean oil and its fried noodle in the same concentration of the city water and the physically refined underground water were determined. As the inhibitor of metal proxidation, BHA and citric acid which are used widely in oil industry as antioxidants were compared. In both cases of soybean oil and its fried noodle, the addition of cupric chloride and ferrous chloride showed prominent proxidant effect. Especially, cupric chloride marked more proxidant effect than ferrous chloride by 3 to 6 times with the elapse of time. In the inhibition activity of metal proxidation, citric acid was more effective than BHA. The 1ppm of Cu +0.01% of citric acid treated soybean oil showed less proxidant effect than the control at the later stage. The inhibition activity of citric acid on $Fe^{++}$ in soybean oil was more effective than $Cu^{++}$ in soybean oil.

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An Experimental Study on the Physical and Mechanical Properties of Concrete Using Recycled Sand (순환잔골재를 활용한 콘크리트의 물리·역학적 특성에 관한 실험적 연구)

  • Kim, Jung-Ho;Sung, Jong-Hyun;Lee, Seung-Yeop;Kwon, Gu-Hyuk;Lee, Sea-Hyun
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.5 no.4
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    • pp.359-365
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    • 2017
  • This study examined concrete characteristics depending on the replacement ratio of recycled fine aggregates, which suits the KS F 2573 concrete recycled aggregate standard. As physical properties, slump, air content, changes in the elapse of time and compressive strength were studied in order to provide basic data for activation of recycled fine aggregate recycling. As a result of experimenting recycled fine aggregate concrete, the increase in the replacement ratio of recycled aggregates led to the increase in slump and air content. Also, when the replacement ratio of recycled fine aggregates was 30%, it was judged that there was no problem with constructability. When the replacement ratio was 30%, recycled fine aggregate concrete had a similar tendency to natural aggregate concrete at a compressive strength of 24MPa. When the replacement ratio was 30%, at a target strength of 24MPa, recycled fine aggregate concrete had the same physical characteristics as natural aggregate concrete. This means that a replacement ratio of 30% is appropriate for replacement of recycled fine aggregates. In future, there will be a need to improve the quality of recycled fine aggregates for activating the use of recycled fine aggregates and further research will have to evaluate physical properties of recycled fine aggregate concrete using improved recycled fine aggregates.

Characteristics of pollutant emission from wallpapers - Around TVOC and HCHO - (벽지에서 발생되는 오염물질 방출특성 - TVOC와 HCHO를 중심으로 -)

  • Jang, Seong-Ki;Kim, Mi-Hyun;Lee, Hong-Suk;Lim, Jun-Ho;Jang, Mee;Seo, Soo-Yun
    • Analytical Science and Technology
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    • v.18 no.6
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    • pp.542-551
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    • 2005
  • This study is to investigate the characteristics of emission concentration according to wallpaper sort and emission time using small chamber method. The target compounds included 45 VOCs and formaldehyde, which were respectively determined by adsorption sampling and thermal desorption coupled with GC/MS method, and by sampling in DNPH cartridge and HPLC method. The emission factor of TVOC and HCHO was detected to $1.1mg/m^2{\cdot}h$ and $0.01mg/m^2{\cdot}h$ respectively, and the wallpapers of 25 satisfied emission standard. TVOC emission factor appeared in order of the concentration of PVC, natural, and Non-PVC wallpaper, while HCHO was detected very low concentration without relation to wallpaper sort. The paraffin hydrocarbons appeared to be the most contributable class of hydrocarbons in terms of their concentrations, followed by aromatics, and olefins, halogenated hydrocarbons was not detected. PVC wallpapers plentifully emitted TVOC above other wallpapers, and toluene was showed higher concentration of 10 times than natural wallpaper. In addition to, emission factor according to elapse was gradually decreased.