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The Preventive Effect of Dexrazoxane and Pentoxifylline on Adriamycin Induced Cardiomyopathy (Dexrazoxane과 Pentoxifylline의 Adriamycin 유발성심근증에 대한 예방 효과)

  • Zhu, Ling;Bae, Eun-Jung;Ha, Il-Soo;Seo, Jung-Wook;Noh, Chung-Il;Choi, Jung-Yun;Yun, Yong-Soo
    • Clinical and Experimental Pediatrics
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    • v.48 no.12
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    • pp.1378-1384
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    • 2005
  • Purpose : We hypothesized dexrazoxane(DXR) and pentoxifylline(PTX) may prevent myocardial damage in adriamycin(ADR)-induced cardiomyopathic rat model. We also investigated their effects on the myocardial apoptosis and fibrosis in ADR induced cardiomyopathy. Methods : The six-week old female Spregue-Dawley rats were divided into control group(CNT, n=4), ADR group(n=6), ADR+DXR group(DXR, n=5), ADR+PTX group(PTX, n=6), ADR+DXR+PTX group(DXPT, n=5). ADR(5 mg/week, twice) was administrated intravenously to rats except CNT group to induce cardiomyopathy. The PTX(50 mg/kg/day) was administered daily from day-0 to Day-21. The DXR(100 mg/kg) was administered 30 minutes before each ADR injection. On day 21, the rats were sacrificed and the degree of histopathologic changes of hypercontraction band necrosis, cytoplasmic vacuolar change and fibrosis were scored. Immunohistochemical staining for Bcl-2 expression and RT-PCR for $TNF-{\alpha}$ and CTGF were performed. Results : Histopathological scores of myocardial damage were significantly higher in ADR rats than CNT rats(P<0.05), and significantly lower in DXPT rats than ADR rats(P<0.01). Myocardial fibrosis was prevented in both PTX rats and DXPT rats. The expression of Bcl-2 was weaker in ADR rats than that in CNT rats(P<0.05), and stronger in both DXR and DXPT rats than that in ADR rats (P<0.05). $TNF-{\alpha}$ concentration of ADR rats was not different from that of treated groups. Conclusion : DXR prevented myocyte apoptosis with increased Bcl-2 expression, and PTX prevented myocardial fibrosis in ADR induced cardiomyopathic rats. The combination therapy of DXR and PTX showed prevention of cardiomyopathy in ADR induced cardiomyopathy rat model.

Therapeutic Effect of Anti-Rotavirus Chicken Egg Yolk Immunoglobulin(IgY) on Diarrhea by Infection of Rotavirus (로타바이러스 감염성 설사에 대한 항-로타바이러스 난황항체의 치료 효과)

  • Lim, In Seok;Lee, Ho Seok;Kim, Wonyong;Choi, Eung Sang;Jung, Dong Hyuk;Jung, Hoo Kil;Yun, Sung Seob;Chun, Ho Nam
    • Clinical and Experimental Pediatrics
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    • v.48 no.12
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    • pp.1354-1361
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    • 2005
  • Purpose : Rotavirus is an enteric pathogen that affects millions of children globally each year. But no specific therapy is available for the management of rotavirus diarrhea. Due to the clear need to define improved modality for treatment of rotavirus diarrhea, we evaluated the efficacy of antirotavirus IgY in the treatment of infants and children with gastroenteritis. Methods : First, the amount of viral particle in the stools of thirteen patients(seven were given IgY, 6 placebo) infected by rotavirus were evaluated for 3 days with the quantitative RT-PCR method. Second, 36 children with known rotavirus infection identified by ELISA or semi-quantitative RT-PCR were evaluated. We gave 5 g anti-rotavirus egg yolk daily in two equally divided doses for 3 days to two groups(an 18 IgY group and an 18 placebo group), respectively after parenteral consent. Daily vomiting frequency, stool frequency, oral intake and urine output were monitored for 3 days, and electrolyte and blood chemistry were checked at the first and third days. Results : First, in the placebo group, the amount of virus particles increased daily, but in the IgY group it decreased daily. Second, when IgY and placebos were given to children infected with rotavirus, diarrhea on the third day decreased significantly in the IgY group, compared with the placebo group. Conclusion : Treatment with antirotavirus immunoglobulin from immunized chicken's egg resulted in a decrease in the amount of viral particles in stools and diarrhea frequency in children. These results suggest that anti-rotavirus IgY is effective in the treatment of rotavirus gastroenteritis.

Exploration of Neurophysiological Mechanisms underlying Action Performance Changes caused by Semantic Congruency between Perceived Action Verbs and Current Actions (지각된 행위동사와 현재 행위의 의미 일치성에 따른 행위 수행 변화의 신경생리학적 기전 탐색)

  • Rha, Younghyoun;Jeong, Myung Yung;Kwak, Jarang;Lee, Donghoon
    • Korean Journal of Cognitive Science
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    • v.27 no.4
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    • pp.573-597
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    • 2016
  • Recent fMRI and EEG research for neural representations of action concepts insist that processing of action concepts evoke the simulation of sensory-motor information. Moreover, there are several behavioral studies showing that understanding of action verbs or sentences describing actions interfere or facilitate current action performance. However, it is unclear that online interaction between processing of action concepts and current action is based on the simulation of sensory-motor information, or other neural mechanisms. The present research aims to explore the underlying neural mechanism that how the perception of action language influence the performance of current action using high-spacial temporal resolution EEG and multiple source analysis techniques. For this, participants were asked to perform a cued-motor reaction task in which button-pressing hand action and pedal-stepping foot action were required according to the color of the cue, and we presented auditorily action verbs describing the responding actions (i.e., /press/, /step/, /stop/) just before the color cue and examined the interaction effect from the semantic congruency between the action verbs and the current action. Behavioral results revealed consistently a facilitatory effect when action verbs and responding actions were semantically congruent in both button-pressing and pedal-stepping actions, and an inhibitory effect when semantically incongruent in the button-pressing action condition. In the results of EEG source waveform analysis, the semantic congruency effects between action verbs and the responding actions were observed in the Wernicke's area during the perception of action verbs, in the anterior cingulate gyrus and the supplementary motor area (SMA) at the time when the motor-cue was presented, and in the SMA and primary motor cortex (M1) during action execution stage. Based on the current findings, we argue that perceived action verbs evoke the facilitation/inhibition effect by influencing the expectation and preparation stage of following actions rather than the directly activating the particular motor cortex. Finally we discussed the implication on the neural representation of action concepts and methodological limitations of the current research.

Effects of Green Tea on Hepatic Antioxidative Defense System and Muscle Fatigue Recovery in Rat after Aerobic Exercise (녹차가 유산소 운동 후 흰쥐 간조직의 항산화 작용 및 근피로 회복에 미치는 영향)

  • 김미지;이순재
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.31 no.6
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    • pp.1058-1064
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    • 2002
  • The purpose of this study was to investigate the effects of green tea on hepatic antioxidative defense system and recovery of muscle fatigue in rat after aerobic exercise. Male Sprague-Dawley rats weighing 150$\pm$ 10 g were randomly assigned to one normal (N) group and aerobic exercise training groups. Exercise training groups were classified into two groups: training (T) group and green tea (TG) group which were supplemented the distilled water and green tea extracts by dringking water during experimental periods, respectively. The experimental rats in exercise training groups (T and TG) ran on a treadmill 30 min/day at a speed of 28 m/min (7% incline) 5 days/week or were cage confined (Normal group) for 4 weeks. And rats were sacrificed with an overdose of pentobarbital injection just after running. Hepatic xanthine oxidase (XOD) activities were not significantly different among three groups. The activity of superoxide dismutase (SOD) in T group was no significant difference from N group, but those of TG groups were significantly increased, compared with that of T group. Hepatic glutathione peroxidase (GSHpx) activites of TG groups showed a similar tendency to that of normal group, but it was increased to 20% in TG group, compared with normal group. The reduced glutathione (GSH) contents in liver was not significantly different from that of any three group. The oxidized glutathione (GSSG) contents in T group was increased to 69%, compared with the normal group, but TG group significantly decreased, compared with the T group. The ratio of GSH/GSSG in liver of T group was lower than that of normal group, but those of TG group was a similar tendency to that of normal group. Contents of thiobarbituric acid reactive substance(TBARS) in T group was increased to 52%, compared with that of normal group but those of TG group were recovered the normal level. Contents of hepatic glycogen in T group were decreased to 23% compared with those of normal group, while that of TG group was the same as normal levels. The contents of serum lactic acid in T group were increased to 261%, compared with normal group, but those of TG group maintained the normal level by green tea supplementations. In conclusion, the effects of green tea in exercise training rats would appear to reduce peroxidation of tissue as an antioxidative defense mechanism and promote recovery of muscle fatigue.

Comparison of Antioxidant Components and Antioxidant Activities of Colored Rice Varieties (Oryza sativa L.) Cultivated in Southern Plain (남부 평야지에서 생산된 유색미 품종별 항산화 성분 및 활성 비교)

  • Park, Ji-Young;Ham, Hyeonmi;Han, Sang-Ik;Oh, Sung-Hwan;Song, You Chun;Cho, Jun Hyeon;Hur, Yeon-jae;Lee, Yu-Young;Lee, Byung-Won;Choi, Yong Hwan
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.8
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    • pp.1214-1220
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    • 2016
  • This study compared antioxidant compounds and antioxidant activities according to various varieties of 18 colored rice. Selected rice cultivars for this study were as follows: black rice (12 cultivars)-Heugjinjubyeo, Nunkeunheugchal, Joeunheugmi, Josaengheugchal, Heuggwang, Heugseol, Shinmyeongheugchal, Shinongheugchal, Shintoheugmi, Cheongpungheukchal, Heughyang, Boseogheugchal, red rice (four cultivars)-Jeogjinju, Jeogjinjuchal, Hongjinju, Geonganghongmi, and green rice (two cultivars)-Nogwonchal and Jungmo1020. These were transplanted on June 30th and cultivated from the Department of Southern Area Crop Science, National Institute of Crop Science in Miryang, Korea. Total polyphenol (TP) content of black rice cultivars was higher than that of red rice varieties. Heugjinjubyeo exhibited the highest TP, which was $9.55{\pm}0.05mg$ gallic acid equivalent/g sample. There were no significant differences between black rice cultivars and red rice cultivars in terms of total flavonoid (TF) level. Heugjinjubyeo and Hongjinju showed the higher TF content than any other variety. Shintoheugmi revealed the highest anthocyanin content ($194.26{\pm}0.65mg/100g$). Methanol extract of Heugjinjubyeo had the highest antioxidant activities. 2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) and 2,2-diphenyl-1-picrylhydrazyl radical scavenging activities of Heugjinjubyeo extract were $14.70{\pm}0.62$ and $30.68{\pm}2.22{\mu}g/mL$, respectively. There were significant correlations between antioxidant compound content and antioxidant activities.

Accumulation of Heavy Metals(Cd, Cu, Zn, and Pb) in Five Tree Species in Relation to Contamination of Soil near Two Closed Zinc-Mining Sites (아연폐광산(亞鉛廢鑛山) 주변(周邊) 토양(土壤)의 중금속(重金屬) (Cd, Cu, Zn, Pb) 오염(汚染)에 따른 5개(個) 수종(樹種)의 부위별(部位別) 중금속(重金屬) 축적(蓄積))

  • Han, Sim Hee;Hyun, Jung Oh;Lee, Kyung Joon;Cho, Duck Hyun
    • Journal of Korean Society of Forest Science
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    • v.87 no.3
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    • pp.466-474
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    • 1998
  • This study was conducted to evaluate heavy metal concentrations(Cd, Cu, Z, and Pb) in the soil of two zinc mines and to correlate heavy metal contents between the soils and trees growing near the mines. Soils and leaves, stems, and roots of five tree species(Corylus heterophylla, Pinus rigida. Populus alba${\times}$glandulosa, Rhododendron mucronulatum, and Robinia pseudoacacia) were collected from Sambo Zinc Mine located in Hwasung and Gahak Zinc Mine in Kwangmyung city in Kyonggido. Soils near two zinc mines were not seriously contaminated by heavy metals, but Zn and Pb concentrations were at toxic level. The heavy metal concentration in soils decreased in the order of Zn, Pb, Cu, and Cd, and decreased with increasing distance from zinc mining sites. Among the five tree species, Populus alba ${\times}$ glandulosa showed the highest heavy metal concentrations in the tissue except for Pb. Particulars, leaves of the species contained the high concentrations of heavy metals to reach the maximum of 91ppm Zn. The roots of Corylus heterophylla contained high concentrations of Cu and Pb. The order of heavy metal concentrations in the tree species was Zn, Cu, Pb and Cd. The concentration of heavy metals in the tree tissues showed a positive correlation with that in soil in which trees are growing. The ratio of heavy metal concentration of trees to that of soils(concentration factor : CF) was highest in Zn and lowest in Pb. Populus alba${\times}$glandulosa had the highest CF value among the five tree species. It was concluded that Populus alba${\times}$glandulosa, based on the high metal uptake ability, could be used for decontaminating of heavy metals from contaminated soils, and Pinus rigida could be used to reflect the level of contamination in soils.

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Biological Control of Anthracnose (Colletotrichum gloeosporioides) in Red Pepper by Bacillus sp. CS-52 (Bacillus sp. CS-52를 이용한 고추 탄저병 (Colletotrichum gloeosporioides) 방제 특성)

  • Kwon, Joung-Ja;Lee, Jung-Bok;Kim, Beam-Soo;Lee, Eun-Ho;Kang, Kyeong-Muk;Shim, Jang-Sub;Joo, Woo-Hong;Jeon, Chun-Pyo;Kwon, Gi-Seok
    • Korean Journal of Microbiology
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    • v.50 no.3
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    • pp.201-209
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    • 2014
  • This study was carried out in order to develop a biological control of anthracnose of red pepper caused by fungal pathogens. In particular, this study focuses on the Colletotrichum species, which includes important fungal pathogens causing a great deal of damage to red pepper. Antagonistic bacteria were isolated from the soil of pepper fields, which were then tested for biocontrol activity against the Colletotrichum gloeosporioides anthracnose pathogen of pepper. Based on the 16S rRNA sequence analysis, the isolated bacterial strain CS-52 was identical to Bacillus sp. The culture broth of Bacillus sp. CS-52 had antifungal activity toward the hyphae and spores of C. gloeosporioides. Moreover, the substances with antifungal activity were optimized when Bacillus sp. CS-52 was grown aerobically in a medium composed of 0.5% glucose, 0.7% $K_2HPO_4$, 0.2% $KH_2PO_4$, 0.3% $NH_4NO_3$, 0.01% $MnSO_4{\cdot}7H_2O$, and 0.15% yeast extract at $30^{\circ}C$. The inhibition of spore formation resulting from cellulase, siderophores, and indole-3-acetic acid (IAA), were produced at 24 h, 48 h, and 72 h, respectively. Bacillus sp. CS-52 also exhibited its potent fungicidal activity against anthracnose in an in vivo test, at a level of 70% when compared to chemical fungicides. These results identified substances with antifungal activity produced by Bacillus sp. CS-52 for the biological control of major plant pathogens in red pepper. Further studies will investigate the synergistic effect promoting better growth and antifungal activity by the formulation of substances with antifungal activity.

Why Central Banks Intervene? (왜 중앙은행은 개입하는가?)

  • Ko, Jong-Moon
    • The Korean Journal of Financial Management
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    • v.12 no.2
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    • pp.273-298
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    • 1995
  • 1960년대, 각국의 환율이 미국의 달러화에 연동(pegging)된 고정환율제도를 근간으로 하는 브레튼우즈(Bretton Woods)체제하에서 각국의 중앙은행은 환율을 일정한 범위 내로 유지하기 위한 정책수단으로 외환시장개입을 적극 활용하였다. 1973년 브레튼우즈체제하의 고정환율제도가 붕괴되고 변동환율제도가 채택된 이후에도 각국의 외환시장개입정책은 계속되었다. 1980년대에 레이건 행정부의 재정팽창정책과 미연방준비은행의 긴축통화정책으로 금리의 지속적인 상승과 미달러화의 큰폭의 절상이 이루어 졌다. 이에 국제무역의 위기를 우려한 미국, 독일, 프랑스, 영국, 일본 등 선진 5개국(Group-5, G5)은 1985년 9월 22일 미 달러화의 절하를 위해 외환시장에 공동으로 개입할 것을 주내용으로 한 플라자합의(Plaza Agreement)를 발표하였다. 그후에도 1987년 2월 23일 열린 루브르협정(Louvre Accord, G-6 Communique)에서 환율을 현수준으로 유지시키기 위한 목표환율대(Target zone)를 설정하고 외환시장개입을 통해 이를 유지하기로 합의한 바 있다. 이후의 구미각국은 환율의 관리를 위하여 국가가 공동으로 외환시장에 개입하곤 했다. 본 논문은 1987년 루브르협정 이후 미국, 독일 및 일본의 중앙은행의 외환시장 개입 정책이 소기의 목적을 달성했는지의 여부를 규명해 보고자 한다. 즉, Federal Reserve, Bundesbank 및 Bank of Japan의 외환시장개입이 현물환율시장(spot market)에서 각각의 변동성을 감소 시켰는지의 여부를 독일의 마르크화 및 일본의 엔화를 중심으로 규명해 보고자 한다. 1981년 루브르협정이후, 미국, 독일 및 일본의 중앙은행은 미국 달러화에 대한 마르크 및 엔화의 환율을 안정시키기 위해 꾸준히 외환시장에 개입해 왔다. 외환시장의 개입유형은 크게 태화외환시장개입(non-sterilized intervention)과 불태화외환시장개입(sterilized intervention)으로 구분할 수 있는데, 전자는 외환당국이 민간부문과 외화채권을 거래함으로써 본원통화의 크기가 변하는 개입형태를 의미하는 반면에 후자는 외환당국의 순외화자산의 크기변화가 본원통화의 변화를 초래하지 않는 경우이다. 즉, 불태화외환시장개입은 순외화자산의 증감이 순국내자산의 증감과 반비례해서 이루어지기 때문에 본원통화의 크기에는 변함이 없다. 외환시장개입이란 외환당국이 은행간 시장에서 민간시잔 참가자들과 행하는 적극적인 외환거래를 의미한다. 반면, 넓은 의미에서의 외환시장개입에는 수동적 외환시장개입이라고 불리는 고객거래가 포함된다. 후자의 거래는 국내통화 및 외화표시 자산의 상대적 공급규모를 변화시킨다는 의미에서 전통적외환시장개입과 동일한 효과를 갖기 때문에 광의의 외환시장 개입으로 분류된다. 외환시장의 개입목적은 크게 세 가지로 분류할 수 있다. 첫째, 환율의 안정적 운영이다. 환율수준이 자유롭게 변화되는 변동환율제도하에서 환율의 지나친 변동으로 인한 실물경제로의 부정적인 영향을 최소화하기 위해서 환율의 지나친 변동으로 인한 실물경제로의 부정적인 영향을 최소화하기 위해서 환율의 안정을 정책 목표로 설정하는 경우와 고정환율제도하에서 환율을 일정수준으로 유지시키기 위해서 외환당국이 외환시장에 개입하는 경우가 여기에 해당된다고 볼 수 있다. 둘째, 환율수준의 균형수준으로의 조정이다. 이때 야기될 수 있는 문제점으로는 환율균형 수준을 어떻게 정의, 추정할 것이냐 하는 점과 목표환율정책이 다른 정책목표와 상충될 수 있다는 점이다. 셋째, 외환당국이 공적외환보유액이나 구성을 변화시킬 목적으로 외환시장에 개입하는 경우이다. 이때의 외환시장개입은 현재의 환율수준이 개입으로 인하여 과도하게 이탈하는 문제가 발생하지 않을 것을 전제로 한다. 본고에서는 현물환율에 영향을 미치는 요소로 미국, 독일 및 일본의 중앙은행의 개입효과, 요일효과, 통화의 공급량(M1), 무역적자의 폭, 산업의 생산량, 생산가격지수(PPI), 소비자물가지수(CPI), 실업률, 옵션의 내재적 변동성 등을 고려한다. 환율의 변동성을 추정하는 식은 GARCH 모델이 사용된다. 본 추정모델은 Dominguez(1993)의 확장이다. Dominguez (1993)의 논문은 GARCH 모델을 써서 미국, 독일 및 일본의 중앙은행의 시장개입효과를 분석했으나, 거시변수를 고려대상에서 제외시켰다. 본 논문은 위의 방법에 거시변수를 삽입하고 모델을 변형시켜서 더 확실한 시장개입효과와 거시변수효과를 밝혔다. 또한 옵션의 내제적 변동성을 구하는 과정에서 American option model을 사용하는 대신, Bourtha & Courtadon (1987)등이 밝힌 바와 같이 American style option이라 할지라도, European Model을 쓰면 더욱더 간편하고, 예측력도 American Model에 뒤지지 않음을 이용하여, European Model을 써서 내재적 변동성을 구한 다음 이것을 독립변수로 이용하였다. 본 모델의 추정 결과는 3국의 시장개입정책이 현물환율과 옵션의 내재적 변동성을 증가시켜서 Louvre 협정이후 각국은 시장개입의 목적을 달성하지 못한 것으로 나타났다.

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PROCESSING OF DRILL SOLUBLE AND ITS AMINO ACID COMPOSITION (Krill solube의 가공 및 아미노산 조성)

  • LEE Eung-Ho;KIM Se-Kwon;CHO Duck-Jae;HAN Bong-Ho
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.12 no.4
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    • pp.235-240
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    • 1979
  • A study on the amino acid composition of raw frozen krill, and krill solubles manufactured in forms of paste and powder has been carried out. The raw frozen krill was thawed, chopped, mixed and homogenized with same amount of water. The mixture was autolyzed or hydrolyzed by tile addition of $0.2\%$ pronase-p, a commercial proteolytic enzyme, to the weight of the raw frozen krill at $45^{\circ}C$ for 4 hours. After a thermal inactivation of enzymes at $95^{\circ}C$ for 15 minutes, the autolysate and the hydrolysate were centrifuged and filtered through gauzes, respectively, and then tile lipid layer in the supernatant was removed, The autolysate and the hydrolysate were finally concentrated under reduced atmospheric pressure in a rotary vacuum evaporator at $45^{\circ}C$ for 1 hour to produce the krill solubles in form of paste. The powdered krill solubles were prepared by the addition of $5\%$ starch to the autolysate and hydrolysate and by means of concentration in the rotary vacuum evaporator at $45^{\circ}C$ for 30 minutes and a forced air drying at $58^{\circ}C$ for 3 hours with a air velocity of 3m/sec. Among the amino acids in raw frozen krill, glutamic acid, lysine, and aspartic acid showed high values in quantity and then followed leucine, alanine, arginine, glycine and proline. The qnantity of histidine was very small and that of cystine was only in trace. The krill solubles in forms of paste and powder prepared by autolysis and hydrolysis with pronase-p revealed almost the same patterns in amino acid composition as in raw frozen krill. In case of free amino acids, a large quantity of it in raw frozen krill consisted of lysine, arginine, proline, alanine and leucine. The quantities of cystine, histidine and glutamic acid were, in contrast, very small. In the soluble krill paste prepared by autolysis, lysine, leucine, threonine and alanine existed in large quantities among the free amino acids and cystine, aspartic acid and histidine existed in small quantities. The contents of almost all of the free amino acids ill soluble krill paste perpared by hydrolysis with pronase-p were increased slightly as compared with those in soluble krill paste prepared by autolysis. In this product, the contents of cystine, histidine and serine were very low and lysine, leucine, arginine and proline were the dominant group in quantities among the free amino acids. The krill solubles in forms of paste and powder were not inferior to whole egg in the view point of its essential amino acid composition.

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Differential Sensitivity of Rice Cultivars to HPPD-Inhibiting Herbicides and their Influences on Rice Yield (HPPD 억제 제초제에 대한 벼 생태형간 약해 차이 및 수량 영향)

  • Kim, Sang-Yeol;Oh, Seong-Hwan;Lee, Ji-Yoon;Yeo, Un-Sang;Lee, Jong-Hee;Cho, Jun-Hyeon;Song, You-Chun;Oh, Myung-Kyu;Han, Sang-Ik;Seo, Woo-Duck;Jang, Ki-Chang;Na, Ji-Eun;Park, Sung-Tae;Nam, Min-Hee
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.57 no.2
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    • pp.160-165
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    • 2012
  • A field study was conducted at Miryang in 2011 to evaluate differential sensitivity of six rice cultivars, three Indica${\times}$Japonica rice (long grain, cv. Hanareumbyeo, Hanareum2, Dasanbyeo) and three Japonica rice (short grain, Nampyung, Ilpumbyeo and Junamjosaeng) cultivars, to benzobicyclon, mesotrione+pretilachlor (MP) and butachlor (control) in transplanting rice and their treatment influences on rice yield. All Indica${\times}$Japonica rice cultivars exhibited susceptible to both benzobicyclon and MP as reflected by higher visual injury and carotenoid biosynthesis inhibition when compared with Japonica rice cutlivars. The percentage of foliar chlorosis of Indica${\times}$Japonica rice was only 0.9~4.7% for benzobicyclon at 13 days after treatment (DAT) and 30.3~64.4% for MP at 5DAT but it increased rapidly to 88.4~91.2% at 12~20DAT. However, most of the Japonica cultivars are tolerant to bezobicyclon and MP. There was no visible leaf chlorosis but carotenoid biosynthesis was slightly inhibited. Based on relative carotenoid content reduction of benzobicyclon and MP to butachlor, the Indica${\times}$Japonica rice showed 4.6~15.6 fold higher compared with the Japonica rice. The heading date of the injured rice plant was delayed by 3 days and panicle number per square meter and ripened grain ratio were reduced as compared with the control treatment of butachlor. Rice yield of the Indica${\times}$Japonica rice cultivars treated with benzobicyclon and MP was reduced by 7~10%, 3~5%. respectively. The result indicates that rice cultivars vary in tolerance to HPPD-Inhibiting herbicides and Indica${\times}$Japonica rices were more susceptible than the Japonica rices to MP and benzobicyclon. Rice yield of the Indica${\times}$Japonica rices was also significantly reduced by the those herbicide treatments.