• Title/Summary/Keyword: 화란

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Weed Occurrence in Upland Crop Fields of Korea (최근(最近) 한국(韓國)의 전작지(田作地) 잡초발생(雜草發生) 분포(分布)에 관(關하)여)

  • Chang, Y.H.;Kim, C.S.;Youn, K.B.
    • Korean Journal of Weed Science
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    • v.10 no.4
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    • pp.294-304
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    • 1990
  • For the survey of weed distribution in the cultivated upland of Korea, weed species were investigated at 2 field by crop of 2 myon per kun in 81 kun selected among the 139 kun of the whole country. 232 species in 46 families were observed, totally. From among the result, 165 species in 39 families the in winter crop field, 189 species in 41 families in the summer crop field were classified. 122 species in 34 families were emerged the from the upland crop field of the whole season. Further more, in the 10 dominant weed species which emerged from upland crop field, Alopecurus aequalis, Chenopodium album, slellaria media, Galium spurieum, Capsella bursa-pastoris and Rorippa islandica were dominated in the winter upland and paddy field, and that Erigeron canadensis, Cyperus amuricus, Equisetum arvense and Arenaria serpyllifolia were dominated in the winter upland field, additionally. Stellaria alsine, Bothriospermum tenellum, Trigonotis peduncularis and Polygonum arviculare were dominated in the winter cropping on drained paddy field, additionally. In the summer crop field, Digitaria sanguinalis, Portulaca oleracea, Acalypha australis, Echinochloa crus-galli, Setaria viridis, Persicaria hydropiper, Amaranthus lividus, commelina communis, Chenopodium album and Cyperecs amuricus were dominated.

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Quality Properties of Chonggak Kimchi Fermented at different Combination of Temperature and Time (발효 온도와 시간 조합을 달리한 총각김치의 품질 특성)

  • Kang, Jeong-Hwa;Kang, Sun-Hee;Ahn, Eun-Sook;Chung, Hee-Jong
    • Journal of the Korean Society of Food Culture
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    • v.18 no.6
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    • pp.551-561
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    • 2003
  • To determine the conditions of the fermentation and storage for Chonggak kimchi in kimchi refrigerator, prepared Chonggak kimchi took into kimchi refrigerators which were controlled at four different modes of the fermented temperature and time, and fermented and kept for 16 weeks. The pH in Chonggak kimchi fermented at $20^{\circ}C$ for 24 hours/stored at $-1^{\circ}C$ dropped greater than all of kimchi fermented at other combinations, and the changes of pH at any combinations were not greater than those in Baechu kimchi, because pH in Chonggak kimchi did not dropped below 4.5. Acidities in Chonggak kimchi were greatly increased at higher temperature. The acidity in Chonggak kimchi during the first week of fermentation was lower than that in Baechu kimchi and then it was rather higher because of the addition of waxy rice paste. In texture, puncture force of Chonggak kimchi was decreased slowly until 8 weeks of fermentation and then did not changed much and the highest values showed in Chonggak kimchi stored directly at $-1^{\circ}C$ without any fermentation. In sensory evaluation, the scores for the carbonated flavor and the sourness were the highest in Chonggak kimchi fermented at $20^{\circ}C$ for 24 hours/stored at $-1^{\circ}C$, but the lowest in Chonggak kimchi stored directly at $-1^{\circ}C$ without any fermentation because of some undesirable flavors. The lowest hardness showed in Chonggak kimchi fermented at highest temperature and the best hardness was in Chonggak kimchi fermented at $5^{\circ}C$ for 3 days or 6 days/stored at $-1^{\circ}C$. The appearance was the best in Chonggak kimchi fermented at $20^{\circ}C$ for 24 hours/stored at $-1^{\circ}C$ and the worst was in Chonggak kimchi stored directly at $-1^{\circ}C$ without any fermentation. The overall acceptability of Chonggak kimchi fermented at $20^{\circ}C$ for 24 hours/stored at $-1^{\circ}C$ was good after 4 weeks of fermentation, but in Chonggak kimchi fermented at $5^{\circ}C$ for 3 days or 6 days/stored at $-1^{\circ}C$ it was good after 6 weeks. Total microbial counts in most of Chonggak kimchi were reached to a maximum number within 7 days, and then decreased similarly at all modes. Leuconostoc spp. and Lactobacillus spp. increased to maximum number of $1.48{\times}10^9\;and\;5.62{\times}10^9$, respectively, in Chonggak kimchi fermented for 7 days. Yeast counts showed a increasing trend not depends on fermenting temperature and they were lower counts than those in Baechu kimchi. Waxy rice paste which added to Chonggak kimchi resulted in increasement of glucose as a carbon source and stimulated to reproduce the microbes in Chonggak kimchi.

Studies on the Organo-mercury Residues in Rice Grain -I. Mercury residues in rice seeds treated with organo-mercury fungicide- (수도(水稻)에 처리(處理)된 유기수은제(有機水銀劑)의 잔류성(殘留性)에 관(關)한 연구(硏究) -제1보(第1報) 침지용유기수은제(浸漬用有機水銀劑)로 처리(處理)된 수도종자중(水稻種子中)의 수은잔류량(水銀殘留量)에 관(關)하여-)

  • Lee, Dong-Suk
    • Applied Biological Chemistry
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    • v.8
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    • pp.87-93
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    • 1967
  • 1) For the micro-analysis of mercury in plant materials, the method of Furutani was shown to be the simplest and most efficient way and the recovery of the assay was about 98%. 2) When the rice grain was soaked in 1/1000 diluted solution of organo-mercury fungicide for 8 hours at the end of March, the amounts of mercury residues in the brown rice and unhulled rice were 8.8 to $9.5\;{\mu}g/g$ seeds and 10.1 to $10.7\;{\mu}g/g$ seeds, respectively. 3) By washing the treated rice seeds with running water for three days, tile residual mercury concentration was reduced to 1/4 to 1/5; thus the mercury residues were 1.86 to $1.92\;{\mu}g/g$ for brown rice and 1.96 to $2.93\;{\mu}g/g$ for unhulled rice. 4) The residual mercury was present more in the unhulled rice than in the brown rice, either before or after washing of the treated seeds. 5) Among the different rice varieties, no difference was observed in mercury residues by seed treatment and washing.

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Neonatal Sepsis and Antimicrobial Susceptibilities in the Neonatal Intensive Care Unit and Nursery (신생아 패혈증의 원인 및 항생제 감수성)

  • Moon, Jin Hwa;Oh, Sung Hee;Kim, Hak Won;Moon, Su Jee;Choi, Tae Yeol
    • Pediatric Infection and Vaccine
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    • v.9 no.2
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    • pp.163-174
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    • 2002
  • Background : To delineate the changes in the causative agents of neonatal sepsis and their antimicrobial susceptibilities in the neonatal intensive care unit and nursery of Hanyang University Hospital during the past 10 years. Methods : Hospital records of 15,144 patients hospitalized at the NICU and nursery of Hanyang University Hospital from 1989 to 1998 were reviewed and neonates diagnosed of neonatal sepsis were sorted and included in the study. The study period was divided into Period A(the first 5 years) and Period B(the second 5 years) to analyse causative agents and their antimicrobial susceptibilities. Results : Neonatal sepsis was diagnosed in 170 patients(1.1%{Period A 1.2%, Period B 1.0%}) among the total of 15,144 inpatients. Two hundred isolates(Period A 109 isolates, Period B 91 isolates) were identified in 186 blood cultures(Period A 99 cultures, Period B 87 cultures) from 170 patients(Period A 91 patients, Period B 79 patients). The average age at the onset of the disease, when the initial blood culture was drawn, was 12.3 days old(Period A 8.8 days, Period B 16.3 days), and the proportion of the early onset disease was 34.7% in Period A and 23.0% in Period B, indicating that neonatal sepsis developed earlier during Period A. Among the isolated organisms including Gram positive bacteria[132(66.0%)], Gram negative bacteria [60(30.0%)], and fungi[8(4.0%)], coagulase negative Staphylococcus(CNS) was the most common organism(69/34.5%), followed by Staphylococcus aureus(36/18.0%), Klebsiella pneumoniae(17/8.5%), Enterococcus(12/6.0%), Enterobacter cloacae(8/4.0%), Escherichia coli(6/3.0%), and Pseudomonas aeruginosae(5/2.5%). The isolated fungi were Candida parapsilosis, Candida albicans, and Trichosporon pullulans. CNS, S. aureus and Acinetobacter baumannii were isolated more frequently in Period A compared to Period B. Antimicrobial susceptibilities of CNS and S. aureus to methicillin and the first generation cephalo sporins were decreased in Period B compare to Period A, those to aminoglycosides were increased in Period B, and vancomycin resistant strains were not identified. K. pneumoniae, Enterococcus, E. coli, and P. aeruginosa were isolated less frequently in Period B, compared to Period A. For K. pneumoniae, antimicrobial susceptibilities to the first generation cephalosporins were low in both Periods A and B, those to tobramycin and gentamicin were increased in Period B, and those to amikacin, ceftriaxone, and trimethoprim-sulfamethoxazole were high in both Periods A and B. Antimicrobial susceptibilities of Enterococcous to ampicillin, penicillin, and the first generation cephalosporins were decreased in Period B, but vancomycin resistant strains were not identified. Conclusion : The occurrence rate of neonatal sepsis during the past 10 years in the NICU and nursery of the Hanyang University hospital was 1.1%, and the most common causitive agents were CNS and S. aureus, to which the antimicrobial susceptibilities to the first line drugs decreased in the later half of the study period with no vancomycin resistant isolates identified. Group B Streptococcus known to be the most common agent causing neonatal sepsis was not identified, and K. pneumoniae was isolated more commonly during the later half of the study period without decreased antimicrobial susceptibilities.

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Clinical Analysis of Influenza in Children and Rapid Antigen Detection Test on First Half of the Year 2004 in Busan (2004 상반기 부산 지역에서 유행한 인플루엔자의 임상 역학적 분석 및 인플루엔자 진단에 있어서의 신속 항원 검사법)

  • Choi, So Young;Lee, Na Young;Kim, Sung Mi;Kim, Gil Heun;Jung, Jin Hwa;Choi, Im Jung;Cho, Kyung Soon
    • Pediatric Infection and Vaccine
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    • v.11 no.2
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    • pp.158-169
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    • 2004
  • Purpose : Although influenza is one of the most important cause of acute respiratory tract infections in children, virus isolation is not popular and there are only a few clinical studies on influenza and diagnostic methods. We evaluated the epidemiological and clinical features of influenza in children and rapid antigen detection test(QuickVue influenza test) on fist half of the year 2004 in Busan. Methods : From January 2004 to June 2004, throat swab and nasal secretion were obtained and cultured for the isolation of influenza virus and tested by rapid antigen detection test(QuickVue influenza test) in children with suspected influenza infections. The medical records of patients with influenza virus infection were reviewed retrospectively. Results : Influenza viruses were isolated in 79(17.2%) out of 621 patients examined. Influenza virus was isolated mainly from March to April 2004. The ratio of male and female with influenza virus infection was 1.2 : 1 with median age of 4 years 6month. The most common clinical diagnosis of influenza virus infection was bronchitis. There was no difference between influenza A and B infection in clinical diagnosis and symptoms. All patients recovered without severe complication. The sensitivity obtained for rapid antigen detection test (QuickVue influenza test) was 93.6% and the specificity was 80.2%, the positive predictive value 40.8%, the negative predictive value 98.8%. Conclusion : With rapid antigen detection test, it is possible early detection of influenza in children. reduction in use of antimicrobial agent and early use of antiviral agent.

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The Study on the Independent Predictive Factor of Restenosis after Percutaneous Coronary Intervention used Drug-Eluting Stent : Case on MDCT Calcium-Scoring Implementation Patient (약물용출 스텐트를 이용한 관상동맥중재술 후 재협착의 독립적 예측인자에 관한 연구 : MDCT calcium-scoring 시행 환자 대상으로)

  • Kim, In-Soo;Han, Jae-Bok;Jang, Seong-Joo;Jang, Young-Ill
    • Journal of radiological science and technology
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    • v.33 no.1
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    • pp.37-44
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    • 2010
  • We sought to confirm an independent factor about in-stent restenosis (ISR) in the patients who underwent drug-eluting stent (DES) and know a possibility as a predictor of measured coronary artery calcium score by MDCT. A total of 178 patients (159 men, $61.7{\pm}10.0$ years of age) with 190 coronary artery lesions were included in this study out of 1,131 patients who underwent percutaneous coronary intervention (PCI) with DES implantation for significant stenosis on MDCT at Chonnam National University Hospital between May 2006 and May 2009. All lesions were divided into two groups with the presence of ISR : group I (re ISR, N = 57) and group II (no ISR, N = 133). Compared to group II, group I was more likely to be older ($65.8{\pm}9.0$ vs. $60.2{\pm}9.9$ years, p = 0.0001), diabetic (21.8% vs. 52.6%, p = 0.0001), have old myocardial infarction (8.8% vs. 2.3%, p = 0.040), left main stem disease (5.3% vs. 0.8%, p = 0.047), and smaller stent size ($3.1{\pm}0.3\;mm$ vs. $3.3{\pm}0.4\;mm$, p = 0.004). Group II was more likely to be smokers (19.3% vs. 42.1%, p = 0.003), have dyslipidemia (8.8% vs. 23.3%, p = 0.019). Left ventricular ejection fraction, lesion complexity, and stent length were not different between the two groups. Total CAC score was $389.3{\pm}458.3$ in group I and $371.2{\pm}500.8$ in group II (p = 0.185). No statistical difference was observed between the groups in CAC score in the culprit vessel, left main stem, left anterior descending artery, left circumflex artery, and right coronary artery. On multivariate logistic regression analysis, left main stem disease (OR = 168.0, 95% CI = 7.83-3,604.3, p = 0.001), male sex (OR = 36.5, 95% CI = 5.89-2,226.9, p = 0.0001), and the presence of diabetes (OR = 2.62, 95% CI = 1.071-6.450, p = 0.035) were independent predictors of ISR after DES implantation. In patients who underwent DES implantation for significant coronary stenosis on MDCT, ISR was associated with left main stem disease, male sex, and the presence of diabetes. However, CAC score by MDCT was not a predictor of ISR in this study population.

Usefulness Evaluation of Artifacts by Bone Cement of Percutaneous Vertebroplasty Performed Patients and CT Correction Method in Spine SPECT/CT Examinations (척추 뼈 SPECT/CT검사에서 경피적 척추성형술 시행 환자의 골 시멘트로 인한 인공물과 CT보정방법의 유용성 평가)

  • Kim, Ji-Hyeon;Park, Hoon-Hee;Lee, Juyoung;Nam-Kung, Sik;Son, Hyeon-Soo;Park, Sang-Ryoon
    • The Korean Journal of Nuclear Medicine Technology
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    • v.18 no.1
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    • pp.49-61
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    • 2014
  • Purpose: With the aging of the population, the attack rate of osteoporotic vertebral compression fracture is in the increasing trend, and percutaneous vertebroplasty (PVP) is the most commonly performed standardized treatment. Although there is a research report of the excellence of usefulness of the SPECT/CT examination in terns of the exact diagnosis before and after the procedure, the bone cement material used in the procedure influences the image quality by forming an artifact in the CT image. Therefore, the objective of the research lies on evaluating the effect the bone cement gives to a SPECT/CT image. Materials and Methods: The images were acquired by inserting a model cement to each cylinder, after setting the background (3.6 kBq/mL), hot cylinder (29.6 kBq/mL) and cold cylinder (water) to the NEMA-1994 phantom. It was reconstructed with Astonish (Iterative: 4 Subset: 16), and non attenuation correction (NAC), attenuation correction (AC+SC-) and attenuation and scatter correction (AC+SC+) were used for the CT correction method. The mean count by each correction method and the count change ratio by the existence of the cement material were compared and the contrast recovery coefficient (CRC) was obtained. Additionally, the bone/soft tissue ratio (B/S ratio) was obtained after measuring the mean count of the 4 places including the soft tissue(spine erector muscle) after dividing the vertebral body into fracture region, normal region and cement by selecting the 20 patients those have performed PVP from the 107 patients diagnosed of compression fracture. Results: The mean count by the existence of a cement material showed the rate of increase of 12.4%, 6.5%, 1.5% at the hot cylinder of the phantom by NAC, AC+SC- and AC+SC+ when cement existed, 75.2%, 85.4%, 102.9% at the cold cylinder, 13.6%, 18.2%, 9.1% at the background, 33.1%, 41.4%, 63.5% at the fracture region of the clinical image, 53.1%, 61.6%, 67.7% at the normal region and 10.0%, 4.7%, 3.6% at the soft tissue. Meanwhile, a relative count reduction could be verified at the cement adjacent part at the inside of the cylinder, and the phantom image on the lesion and the count increase ratio of the clinical image showed a contrary phase. CRC implying the contrast ratio and B/S ratio was improved in the order of NAC, AC+SC-, AC+SC+, and was constant without a big change in the cold cylinder of the phantom. AC+SC- for the quantitative count, and AC+SC+ for the contrast ratio was analyzed to be the highest. Conclusion: It is considered to be useful in a clinical diagnosis if the application of AC+SC+ that improves the contrast ratio is combined, as it increases the noise count of the soft tissue and the scatter region as well along with the effect of the bone cement in contrast to the fact that the use of AC+SC- in the spine SPECT/CT examination of a PVP performed patient drastically increases the image count and enables a high density of image of the lesion(fracture).

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Effects of Applying Cattle Slurry and Mixed Sowing with Legumes on Productivity, Feed Values and Organic Stock Carrying Capacity of Winter Forage Crops in Gyeongbuk Regions (경북지역에서 액상우분뇨 시용과 콩과작물의 혼파가 동계사료작물의 생산성, 사료가치 및 단위면적당 유기가축 사육능력에 미치는 영향)

  • Hwangbo, Soon;Jo, IK-Hwan
    • Korean Journal of Organic Agriculture
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    • v.21 no.3
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    • pp.451-465
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    • 2013
  • This study was conducted to estimate Hanwoo carrying capacity when whole crop barley, rye, wheat and tritcale as winter forage crops was grown on different applying sources (chemical fertilizer, cattle or organic fertilizer) and mixed sowing combination with hairy vetch or forage pea during the period of 2011~2012. The experimental plots within whole crop barley or rye were consisted of 7 treatments, which were non-fertilizer, chemical fertilizer (P+K), chemical fertilizer (N+P+K), organic fertilizer, cattle slurry, cattle slurry with hairy vetch, and cattle slurry with forage pea. Each plot was triplicates and experimental treatments were allocated in the randomized complete block design. For whole crop barley, annual mean dry matter (DM) and total digestible nutrients (TDN) yields were the highest in N+P+K plots, but there were no significant differences among organic fertilizer, cattle slurry and mixed sowing with legumes. The TDN were the highest in mixed sowing plots of forage pea plus cattle slurry application. As 450 kg Hanwoo heifers were fed diets included 70% whole crop barley, organic fertilizer, cattle slurry application and mixed sowing plots of forage pea is capable of raising average 2.8 to 3.1 heads/ha a year. For whole crop rye, annual mean DM were the highest in N+P+K plots, but there were no significant differences among cattle slurry. Organic fertilizer application significantly increased TDN and relative feed value (RFV) in comparison with treatments of N+P+K fertilization as chemical fertilizers. In case of 450 kg Hanwoo heifers fed diets included 70% forage rye, it is estimated that cattle slurry application (mixed sowing with legumes) plots can rear average 2.8~ 3.2 heads/ha a year. For whole crop wheat, annual DM, crude protein, and TDN yields of application groups and mixed sowing treatment with legumes showed 6.90~7.44, 0.53~0.60 and 4.35~5.04 ton/ha, respectively. In case of 450 kg Hanwoo heifers fed diets included 70% forage rye, it is estimated that cattle slurry application (mixed sowing with legumes) plots can rear average 3.1~3.7 heads/ha a year. For Triticale, TDN yield was significantly (P<0.05) higher N+P+K plots, organic ferilizer, cattle slurry, cattle slurry with legumes than for no fertilizer and N+P+K plots. The Crude protein (CP) contents were the highest in mixed sowing plots of forage pea plus cattle slurry application. In case of 450 kg Hanwoo heifers fed diets included 70% forage triticale, it is estimated that cattle slurry application (mixed sowing with legumes) plots can rear average 3.4~3.7 heads/ha a year. It can be concluded that, on the basis of DM yield, not only mixed sowing with legumes by applying cattle slurry rather than single sowing of whole crop barley or whole crop rye enhanced production yield and feed values, but also it could be a substitute for imported grains as dietary protein sources in the case of feeding Hanwoo.

Studies on the Cellulase produced by Myriococcum of albomyces (Myriococcum albomyces가 생산하는 Cellulase에 관한 연구)

  • Chung, Dong-Hyo
    • Applied Biological Chemistry
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    • v.14 no.1
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    • pp.59-97
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    • 1971
  • As a study on the cellulase of Myriococcum albomyces the culture media for enzyme formation and properties of its crude preparation were investigated and the crude enzyme preparation was further fractionated. The results are summarized as follows: 1. Wheat bran solid culture produced stronger activities of cellulase than rice bran or defatted soy bean meal solid culture. 2. Shaking culture with wheat bran, rice bran or defatted soy bean meal produced higher cellulase activities than solid culture with the corresponding media. 3. The enzyme formation was higher at $45^{\circ}C$ than at $37^{\circ}C$ or $50^{\circ}C$ regardless of the kind of culture medium. 4. The formation of CMCase activity was more promoted by organic nitrogen source than inorganic nitrogen source. 5. The formation of cellulase activities were increased 1.5 to 3.0-fold by adding CMC, Avicel or cellulose powder as an inducer into 5% wheat bran basal medium. 6. Cellulase production using a tank culture procedure with addition of CMC or Avicel as an inducer was the highest at fifth day and thereafter decreased slightly. 7. The crude enzyme preparation showed pH optimum in 4.0 to 4.5, and pH stability in the range of 3.5 to 8.0. Optimum temperature for the activity was $65^{\circ}C$ which was higher than among other cellulases and it was stable at $60^{\circ}C$ for 120 minutes. 8. Dialyzed crude enzyme was activated by $Ca^{++}$ and $Mg^{++}$, but inhibited by $Hg^{++}$, $Cu^{++}$ and $Ag^{+}$. 9. Four different types of cellulase, i. e., fraction I, fraction II-a, fraction II-b, and fraction III were purified from the culture filtrate of Myriococcum albomyces through a sequence of ammonium sulfate fractionation, and elution chromatography on DEAE-Sephadex A-25, Amberlite CG-25 type 2 and hydroxyapatite columns. 10. These four cellulase fractions were showed to be homogenous by electrophoresis and ultracentrifugation and also gave a typical ultraviolet absorption spectrum of protein. 11. Four purified fraction showed different specificity toward substrates, fraction I has a stronger activity toward Avicel, cellulose powder, and gauze than that of other cellulase fractions. Fraction II-a had a powerful activity toward cellobiose but it was almost inactive agaisnt fibrous cellulose contrary to fraction I. On the contrary, the main component fraction II-b had a fairly higher activity on CMC and Avicel. Activity of fraction II-b toward cellobiose was about one-third of that of fraction II-a and activity on Avicel was lower than that of fraction I. Fraction III had a more powerful activity in decreasing viscosity of CMC. 12. Final hydrolysis products of fibrous cellulose by each fraction were cellobiose and glucose. Whereas oligosaccharides were predominant in the early stage of hydrolysis, prolonged reaction produced more glucose than cellobiose. Fraction I and fraction II-a acted synergically on Avicel. 13. Optimum pH for the activities of cellulase fraction I, fraction II-a, fraction II-b and fraction III were found to be 5.5, 5.0, 4.0 and $4.0{\sim}4.5$, respectively. These fractions were found to be stable in the range of pH $3.0{\sim}7.5$. 14. Optimum temperature for the activities of fraction I, fraction II-a, fraction II-b, and fraction III were $50^{\circ}C$, $55^{\circ}C$, $60^{\circ}C$ and $55^{\circ}C$, respectively. No less of activity was found by heating 120 minutes at $55^{\circ}C$ and fraction II-a was more stable than the others at $60^{\circ}C$. 15. Fraction I and fraction II-b were activated by $Ca^{++}$ and $Mg^{++}$ but inhibited by $Hg^{++}$ and $Ag^{+}$.

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Studies on the N-compounds during Chung-Kook-Jang Meju Fermentation (1) -Changes of Soybean Protein during Chung-Kook-Jang Meju Fermentation- (청국장(淸國醬) 메주 발효과정중(醱酵過程中)의 질소화합물(窒素化合物)의 소장(消長)에 관(關)한 연구(硏究)(I)-대두단백질(大豆蛋白質)의 소장(消長)에 관(關)하여-)

  • Park, Ke-In
    • Applied Biological Chemistry
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    • v.15 no.2
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    • pp.93-109
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    • 1972
  • Three lots of Chung-Kook-Jang were prepared by the use of 2 strains of Bacillus subtilis and Bacillus natto. For four samples taken from each lot in 12 hrs interval changes of nitrogenous compounds, insoluble protein, water soluble protein, peptides, free amino acids, amino and ammonia nitrogens during Chung-Kook-Jang fermentation, were studied together with the changes of moisture, pH, proteolytic enzyme activity. In addition the average peptide length of the peptides of a Bacillus subtilis lot was determined by the method of molecular sieving using ion exchange resin. The results were as follows: 1. The contents of moisture and total-nitrogen changed little in all samples throughout the fermentation as it would be expected. 2. In all three experimental lots the pH became higher gradually from the initial value of 6.65 to the final $7.5{\sim}7.85$ during the fermentation. Proteolytic enzyme activities, in accordance with this pH change, steadily increased up to $48{\sim}60$ hrs. of fermentation and then slightly decreased, probably affected by the high pH. The most strong proteolytic activity was observed in the experimental Chung-Kook-Jang fermentation lot using the Bacillus subtilis K-27 isolated by the author. 3. The contents of insoluble protein nitrogen in soybeans increased markedly (5%) by the cooking, after steeping 12 hrs in water. During the Chung-Kook-Jang fermentation, however, it decreased from 1/2 to 1/10 of that of the cooked soybeans. 4. The contents of water soluble protein nitrogen (5%) whereas, greatly decreased to the value of 1.0% by the cooking; but little changed further during the fermentation, 5. The total contents (0.25%) of peptides, amino, and ammonia-nitrogens, PAA-N., increased almost double by the cooking and steadily became higher as the fermentation proceeded, reaching finally up to$4{\sim}7%$ in 72 hrs fermentation. 6. The amounts of free amino acids of soybean generally decreased during the processing of cooking, even some of them like glutamic acid were destroyed completely, However in the subsequent Chung-Kook-Jang fermentation for 72 hrs., they showed from several to a few hundreds folds increases depending upon the kinds of amino acids. Valine which was contained in HCl-hydrolyzed steeped or cooked soybeans in amounts $220{\sim}267mg%$ was not detected at all as the free amino acid in all fermented samples. 7. Average peptide length (APL) of all fractions, eluted and fractionated by using the Dowex-50 ion exchange resin column, and fraction collector showed the highest value for the cooked soybean and then decreased as the fermentation proceeded. The APL value of effluent showed the highest in 12 hrs fermented sample, The value decreased thereafter by fermentation.

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