방사균(放射菌)에 의한 5' - Nucleotide 류의 생산에 관한 연구 : 제1보 5' - Phosphodiesterase 생산균의 분리 Part 1. Isolation of 5' - phosphodiesterase Producing Microorganisms

김홍집,배종찬,황규인,공운영 한국농화학회 1979 Applied Biological Chemistry (Appl Biol Chem) Vol.22 No.4

RNA degrading bacteria were isolated from soil of Korea. One strain (no. JSC-114), having strong 5'-phosphodiesterase activity, was identified as belonging to the genus Streptomyces on the basis of taxonomic characteristics. The optimum conditions of 5'-phophosdiesterase production were found at 30℃ for 4 day in a medium containing 4.5% of soluble starch, 0.15% of peptone, 0.6% of yeast extract, 0.1% of MgSO₄·7H₂O, 0.01% of CaCl₂·2H₂O, 0.25% of KNO₃, and 0.5% of KH₂PO₄(pH 7.0). The maximum production rate of 5'-nucleotides from yeast RVA was 95% at 40-45℃ for 4hrs, and the products were identified as 5'-IMP, 5'-GMP, 5'-CMP and 5'-UMP(5.5 : 5.0 : 4.9 : 5.0).

DNA marker를 이용한 벼의 조직배양 효율개선

김홍집,김태헌,손재근 경북대학교 농업과학기술연구소 2009 慶北大農學誌 Vol.27 No.-

벼의 약 및 현미 배양효율과 관련된 DNA marker를 이용하여 인디카형 벼 품종인 'IR 36'의 조직배양 효율을 개선하기 위하여 실험한 결과를 요약하면 다음과 같다. 벼품종 간에 약 및 현미배양 효율을 비교한 결과 자포니카 > 통일형 > 인디카 형의 순으로 나타났다. 그러나 MGRI집단의 약배양에서 식물체분화율이 높은 계통으로 선발된 'MGRI 079'와 'MGRI 036'의 약배양 효율은 각각 19.8%, 19.9%로 가장 높게 나타났다. 'MGRI 079'에 'IR 36'이 여교배되어 양성된 90 계통에 대한 marker검정을 실시하여 positive band를 나타내는 34계통을 선발할 수 있었다. 선발된 34계통 중 10 계통의 약배양에서 캘러스 형성률은 'IR 36' 보다 현저히 높았다. 선발된 10 계통의 현미배양에서도 캘러스형성 능력과 식물체재분화율이 'IR 36' 보다 높게 나타났다. 계통 중에서 식물체분화능력이 높은 계통으로 선발된 -28은 간장이 'IR 36'보다 큰 편이었으나 출수기와 미립특성은 'IR 36'과 비슷하였다. The purpose of this study was to improve the culturability of 'IR 36', a indica type rice cultivar using DNA marker associated with the ability of plant regeneration in anther and seed culture. The culturability of 6 rice cultivars and 2 indica/japonica lines ('MGRI 036', 'MGRI 079') were investigated in anther and seed culture. The culturability of 3 japonica rice cultivars were much higher than tongil and indica rice cultivars, and 'MGRI 036' and 'MGRI 079' has high culturability with 20% regenerability, also. 34 4 lines were selected by marker screening using RZ400 among 90 lines derived from a cross between 'MGRI 079' and 'IR 36'. The frequency of callus formation of 10 lines were higher than 'IR 36' in anther culture among selected 34 lines. The ability of plant regeneration of 10 lines were higher than 'IR 36' in the seed culture among selected 34 lines. A promising line, -28, was selected to have better culturability in the anther and seed culture among selected 34 lines. The heading date and grain shape of the -28 was similar to 'IR 36'. Using the RZ400 DNA marker associated with the culturability will be useful method for improving of indica rice culticvar's culturability in rice breeding program.

수소/공기 대향류 확산화염의 비선형 음향파 응답특성에 관한 연구

김홍집,정석호,손채훈,Kim, Hong-Jip,Chung, Suk-Ho,Sohn, Chae-Hoon 대한기계학회 2003 大韓機械學會論文集B Vol.27 No.8

Steady-state structure and acoustic-pressure responses of $H_2$/Air counterflow diffusion flames are studied numerically with a detailed chemistry in view of acoustic instability. The Rayleigh criterion is adopted to judge acoustic amplification or attenuation from flame responses. Steady-state flame structures are first investigated and flame responses to various acoustic-pressure oscillations are numerically calculated in near-equilibrium and near-extinction regimes. The acoustic responses of $H_2$/Air flame show that the responses in near-extinction regime always contribute to acoustic amplification regardless of acoustic-oscillation frequency Flames near extinction condition are sensitive to pressure perturbation and thereby peculiar nonlinear responses occur, which could be a possible mechanism in generating the threshold phenomena observed in combustion chamber of propulsion systems.

액체로켓엔진 연소실에서의 상온 음향 시험

김홍집,고영성,이광진 대한기계학회 2004 大韓機械學會論文集B Vol.28 No.1

75톤급 가스발생기 연료 및 산화제 매니폴드 유동해석을 통한 유동균일성 파악

김홍집,최환석 한국항공우주학회 2008 한국항공우주학회 학술발표회 논문집 Vol.- No.-

`92년도 질병발생 분석과 예방 대책

김홍집 대한양계협회 1993 월간 양계 Vol.25 No.2

닭의 괴사성 장염에 대한 병리학적 연구

김홍집,강문일,정운익,Kim, Hong-jib,Kang, Mun-il,Chung, Un-ik 대한수의학회 1997 大韓獸醫學會誌 Vol.37 No.1

From January of 1991 to December of 1992, 42 chickens collected from 21 poultry farms and also diagnosed as necrotic enteritis(NE) was examined clinical signs, gross and histopathological findings. Main clinical signs were characterized by decreased appetite, mild to severe depression, reductance to move, ruffled feathers, greenish to yellow-browinish diarrhea sometimes including blood. As progressed, diseased chickens showed feces mixed with necrotic debris which detached from the intestinal mucosa and mostly resulted in the death. In chronic cases, there were dirty feathers around cloaca due to diarrhea and notably retarded growth. Principle gross lesions were usually confined to the jejunum and ileum, especially toward the lower part of Meckel's diverticulum. The part of small intestine was frequently distended with gas, and also showed mucosal congestion and hemorrhages with varying degrees. Sometimes, the intestinal mucosa was thickened, and also covered with fibronecrotic psuedomembrane. In addition, there were focal necrosis and severely multifocal ulcreation in the mucosa of small intestine. Major histopathological findings included villous necrosis and erosion of the small intestine covering with lots of bacterial colonies, inflammatory cell infiltration in the lamina propria, and dilatation and hyperplasia of crypts. Luminal exudate contained bacterial colonies, fibrin, erythrocytes, and desquamated epithelium. Thirteen(61.9%) out of 21 NE-occurring farms were complicated with intestinal coccidiosis.

Infectious bursal disease virus 감염이 닭 괴사성 장염의 병원성에 미치는 영향

김홍집,강문일,정운익,Kim, Hong-jib,Kang, Mun-il,Chung, Un-ik 대한수의학회 1996 大韓獸醫學會誌 Vol.36 No.4

For understanding the role of infectious bursal disease virus(IBDV) to the pathogenesis of necrotic enteritis due to Clostridium perfringens(CP), all 15 day-old chickens used were divided as the following groups; A and E group with the feeding of feed contaminated with CP, B group with oral adminstration of IBDV($50{\mu}l/head$, $10^{3.4}EID_{50}$ of $P_4$ strain) and simultaneously feeding of feed contaminated with CP, C group treated with IBDV alone, F group with the feeding of feed contaminated with CP at 3 weeks after oral inoculation of IBDV, D and G group with the feeding of normal feed as controls. In mortality, B group(30%) was not a difference compared to A group(20%)(p>0.05), but in the pathological lesions the former was more severe degree than the latter. The mortality of F group(70%) was a significant difference to those of A, B or E group (20%)(p<0.01). Also, showed much F group more marked lesions than A, B or E group. In the chickens occurred the death during the study, mean concentration of CP was reached at $10^8{\sim}10^9CFU/g$ in the intestinal contents. B group showed higher mortality and more severe pathological changes than A and E group. Consequently, the results in the study were confirmed that the IBDV could be a role as a enhancing factor in pathogenesis of necrotic enteritis due to CP under the field condition.

닭의 장염발생 조사

김홍집,강문일,정운익,Kim, Hong-jib,Kang, Mun-il,Chung, Un-ik 대한수의학회 1996 大韓獸醫學會誌 Vol.36 No.4

The purpose of the survey was to understand the field situation on the occurrence of enteric diseases in poultry farms in Korea. During the period from January of 1991 to December, 1992, 279(35.8%) out of 779 farms surveyed experienced the cases of enteritis in their chickens. The farms with diarrheal problems consisted of 157(45.1%) of 348 broiler flock, 28(32.6%) of 86 breeder flock, and 94(27.2%) of 345 layer flock. The main diseases causing enteritis were frequently appeared as infectious bursal disease(27.3%), colibacillosis(22.6%), and coccidiosis(8.6%). Necrotic enteritis(NE) in chicken occurred in 21 farms(2.7%) among 779 farms examined. The outbreaks of NE were divided 4.7% in breeders, 4.0% in broilers, and 0.9% in layers, respectively. NE occurred mainly in the age(71.4%) of 20~30 days and the mortality was varying from 1.4% to 10.0% for broilers, 3.0% for layers and 0.8% for breeders. Seasonal prevalence of NE showed the highest as 52.4% in summer and followed by 33.3% in autumn, 9.5% in spring and 4.5% in winter.

닭의 괴사성 장염 및 건강 계군에서 분리한 Clostridium perfringens의 신속동정 및 독소형 분석

김홍집,강문일,정운익,Kim, Hong-jib,Kang, Mun-il,Chung, Un-ik 대한수의학회 1997 大韓獸醫學會誌 Vol.37 No.1

About Clostridium perfringens causing clinically necrotic enteritis or isolated from the intestinal contens of healthy chicken, We examined the usefulness of a rapid identification method by gas-liquid chromatography as well as the types of toxins. For this study, there were used 169 chickens including 116 broilers, 27 layers and 26 breeders which collected from 9 healty flock and 21 diseased flock showing necrotic enteritis. Among them, Cl perfringens was isolated from 30 chickens(17.8%) including 7 breeders(26.9%), 5 layers(18.5%) and 18 broilers(15.5%). Isolation of Cl perfringens was mainly from ceca (100%) and followed by small intestines(70.0%) and livers(16.7%), respectively. Average concentration of the pathogen in intestinal contents was $10^{3.8}CFU/g$ in cases occuring necrotic enteritis and on the contrary $10^{3.8}CFU/g$ in healthy cases. All isolates tested showed the same characterstics in biochemical tests compared to those in standard strain. Analysis of gas-liquid chromatography to volatile fatty acids produced by Cl perfringens in PYG broth showed the typical peaks of acetic and butyric acids compatible with the standard chromogram and was confirmed as a effective and reliable tool for rapid identification of the bacteria. Toxin types of 30 strains were mostly classified in A type(26 isolates) and the rest in C type(2 isolates) and unidentifed type(2 isolates). All the isolates were highly susceptible to amphicillin, amoxicillin and cephalothin.