고핵산 함유 Saccharomyces cerevisiae 균주를 이용한 정미성 효모 추출물의 제조

김재식,김진욱,심원,김정완,박관화,백운화,Kim, Jae-Sik,Kim, Jin-Wook,Shim, Won,Kim, Jung-Wan,Park, Kwan-Hwa,Pek, Un-Hua 한국식품과학회 1999 한국식품과학회지 Vol.31 No.2

핵산 함량이 높은 변이주 Saccharomyces cerevisiae B24를 산업적으로 활용하기 위해 배양 후 자기소화 혹은 효소 분해법으로 효모 추출물을 제조하였다. 배양액의 균체 농도를 10% (w/w)로 하고 pH 5.0, $50^{\circ}C$에서 서서히 교반하면서 48시간 자기소화시켰을 때 세포 내용물이 효모 추출물로 이전되는 수율은 65% 정도였으나 리보핵산은 정미력이 없는 다른 성분으로 분해되어 정미성 핵산성분인 5'-IMP나 5'-GMP가 거의 검출되지 않았다. 반면 $90^{\circ}C$ 이상의 온도로 B24 배양액 1 L를 열처리하여 핵산 분해 효소를 불활성화시키고 세포벽을 변성시킨 다음 ${\beta}-1,3-glucanase$, phosphodiesterase, adenylic deaminase, protease 등을 순차적으로 작용시켜 정미성 5'-IMP와 5'-GMP가 총 3.2% 함유된 효모 추출물(고형분 함량 70%) 84 g을 얻을 수 있었고 이 때 추출물 수득율은 고형분 기준으로 85% 이었다. 반면 모균주인 S. cerevisiae ATCC 7754를 효소적으로 분해할 때 정미성 5'-IMP와 5'-GMP가 총 2.2% 함유된 효모 추출물(고형분 함량 70%)을 77 g밖에 얻지 못하였다. Yeast extracts were prepared using either autolysis or enzymatic digestion methods for industrial application of the Saccharomyces cerevisiae B24 strain developed previously to have high RNA content. Extraction ratio of yeast extract from yeast cell reached 65% when autolysis of yeast slurry having 10% solid content was induced at $50^{\circ}C$ and pH 5.0 by agitating with 100 rpm. However, neither 5'-IMP nor 5'-GMP was detected from the autolyzate. In another attempt to prepare a yeast extract S. cerevisiae B24 culture was treated at $90^{\circ}C$ and then treated by various enzymes including ${\beta}-1,3-glucanase$, phosphodiesterase (nuclease P1), adenylic deaminase, and a protease. The yeast extract prepared by the enzymatic digestion method contained 3.2g of 5'-IMP and 5'-GMP/100g dry yeast extract.

HS상의 식료품 분류체계와 식품업계의 대응방안

김재식 한국식품산업협회 1986 좋은식품 Vol.83 No.-

면역학적 노화 기전에 관한 연구: T 및 B 세포의 변화

김재식,이원길,서장수,송경은,이중원,이난영,Kim, Jay Sik,Lee, Won Kil,Suh, Jang Soo,Song, Kyung Eun,Lee, Joong Won,Lee, Nan Young,Weksler, Marc E. 대한면역학회 2001 Immune Network Vol.1 No.3

Background: An immunological approach for aging mechanism appears to be important. Lymphocyte subsets analysis in peripheral blood is widely performed to assess the immune status and to diagnose and monitor various diseases. Some lymphocyte subsets are known to change with age, but only few data about age-related reference ragnes for these subsets in healthy individuals have been reported. So we attempted to report reference ranges for these subsets in each age group and review changes of the results with age for the secondary studies about immune cell function as lymphocyte blast transformation and immunoglobulin gene rearrangement (VDJ) including recombination activating genes (RAG-1 and RAG-2). Methods: Lymphocyte subset analysis was performed on 302 subjects, 189 males and 113 females with age group of all decades of life. Two color direct immunofluorescene flow cytometry (FCM) was done using $Simultest^{TM}$ IMK-Lymphocyte kit (Becton Dickinson, USA), $FACScan^{TM}$ (Becton Dickinson, USA) and $FACSCalibur^{TM}$ (Becton Dickinson, USA). Lymphocyte subsets analysed were T ($CD3^+$) and B cells ($CD19^+$), helper/inducer T ($CD4^+$) and suppressor/cytotoxic T cells ($CD8^+$), helper/suppressor ($CD4^+/CD8^+$) ratio and natural killer (NK) cells ($CD3^-CD16^+/CD56^+$). The absolute numbers of each subset were calculated from total lymphocyte counts. Data collected was analysed using SAS 6.12. A P-value of < 0.05 was considered significant. Results: We reported the counts and percentages of lymphocyte and these subsets in each age group. There were no statistically significant differences between male and female subjects. The percentage of $CD4^+$ T cells, and the count of NK cells did not show the significant difference among the various age groups. The age-related changes observed in our study were as following: 1) a decrease in the percentages of T cells, B cells and $CD8^+$ T cells ; 2) a decrease in the counts of B cells and $CD8^+$ T cells ; 3) an increase in the percentage and count of NK cells ; and 4) an increase in the $CD4^+/CD8^+$ ratio. Conclusion: The characteristics of aging process appeared to be showing a marked decrease of lympocyte subsets T and B cells as well as T8 ($CD8^+$). The age-related increase of the percentage of cells bearing NK marker can be interpreted as a compensatory consequence to cope with the decrease of T cells related to the thymic involution. These changes with age appeared to be for the secondary study about immune cell function as lymphocyte blast transformation and immunoglobulin gene rearrangement.

면역전기영동법의 개량

김재식 慶北大學校 醫科大學 1985 慶北醫大誌 Vol.26 No.4

단백전기영동법과 면역전기영동법은 임상에서 일상검사화되었다. 그러나 면역전기영동법은 번거러운 방법 자체와 그 결과의 분해능(resolution)에 문제가 있어서 개량의 여지가 있다. 저자는 종래의 면역전기영동법에 다소의 개량을 시도하여 다음과 같이 요약할 수 있었다. 보통세균배지용인 Bacto-agar 15 g 로부터 acetyl화, chloroform 추출, petroleum ether 침전 및 탈 acetyl화 원리를 이용하여 8 g 의 정제 agarose-K를 얻을 수 있었고 국산화가 이루어졌다. 재생 X-ray film을 지지체판으로 쓸 수 있었다. 면역전기영동용 universal 형판을 설계하여 Kim's universal 면역전기영동형판(凸주형)을 제작하였다. Bacto-agar은 agarose와 agarose-K에 비하여 혈청단백전기영동에 있어서 각 분획의 형태가 부정하고 분해능도 불량하여 부적합하였고 면역전기영동상은 전기영동상보다는 양호하였으나 분해능이 좋지 않아서 역시 면역전기영동법에도 부적합하였다. Agarose와 agarose-K를 사용한 혈청단백전기영동 및 면역전기영동상에서 상호간에 별 차이를 인정할 수 없었다. 검체첨가에 있어서 원형 공(孔)보다 수직 구(溝)가 혈청단백전기영동에 적합하였고 면역전기영동에 있어서는 원형 공이 수직구보다 더 분해능이 좋았다. 면역전기영동에 있어서 검체첨가가 1 ㎕인 경우 모른 영역의 침전윤의 분해능이 가장 적합하여 항혈청과의 비를 20:1로 유지하는 것이 가장 이상적이고 우수하다고 보았고 검체의 희석은 1:5, 1:10 및 1:20, 3자간에 별다른 차이를 인정할 수 없었기 때문에 관례의 1:10을 중심으로 그때 그때 필요에 따라 조정하는 것이 좋다고 생각된다. Agarose-K 지지체, Kim's universal 면역전기영동 및 재생 X-ray film 지지판을 국산 킷트화하여 간편 저렴한 면역전기영동법의 개량이 가능하게 되었다. The serum protein electrophoresis and immunoelectrophoresis has become routine tests in clinical laboratory medicine. However the immunoelectrophoresis requires more improvement in the method itself and resolution of its precipitation arcs formed as the results. Agarose-K was purified from Bacto-agar by acetylation principle for self production. It was possible to use the used X-ray film as the plate for media (agar-gel) by clearing with 50% NaOH. Kim's universal IEP template was made for the convenient for both serum protein electrophoresis and immunoelectrophoresis because of poor resolutions in electrophoretic patterns. There was no difference between agarose (commercial) and agarose-k in serum protein electrophoresis and immunoelectrophoresis patterns. The round well appeared to be appropriate for immunoelectrophoresis patterns and the vertical sample hole for electrophoresis patterns. The appropriate amount of the sample(serum) appeared to be 1㎕ for high resolution in immunoelectrophoresis patterns. There was no difference in immunoelectrophoresis patterns by 1:5, 1:10 and 1:20 dilutions of sera. The simple, convenient and economical self-made Kim's universal IEP kit seemed to be most practical and useful in routine clinical laboratory.

실업교원 자격제도의 문제점과 개선방향에 관한 연구

김재식,정철영,나승일,정남용,이용환 한국농·산업교육학회 2001 농업교육과 인적자원개발 Vol.33 No.4

The purposes of this study were to review the status in vocational teacher qualification, and to recommend the improvement strategies at this system. This study was carried out through reviewing extensive literature, surveying opinions from members in the Provincial Offices of Education, professors in vocational teacher training institute, teachers in the vocational high schools, and asking opinions from a panel of experts. Introduced directions for restructuring the qualification of vocational teachers were as follows: To improve vocational teacher qualification system, it is necessary 1) to realize vocational teacher qualification assessment standard, 2) to give much more weight on major credit, 3) to unify a similar vocational-related major departmentsubjectteacher qualification in the long run, 4) to introduce the key competencies exam for qualification assessment, 5) to establish assessment standard for improving competency of foreign languageinformation technology, 6) to establish renewal system of vocational teacher qualification, 7) to improve qualification system for practical teachers.

직업탐구 영역으로서‘상업경제’교과에 대한 검토와 제언

김재식 한국경영교육학회 2004 경영교육연구 Vol.35 No.-

Due to "economics" included in subject title, economics parts are relatively emphasized in the subject of Commercial Economics, but commerce or business(management) parts are not so much emphasized. Commercial Economics has some problems in its title and a lot of problems in its contents. The purpose of this studies were (1) to review if the Commercial Economics is appropriate as a subject name, and (2) to find some problems on the contents of the subject in the view point of correctness, suitabilities and balance, and then (3) to suggest the short-term and long-term solutions for the problems. The needed measures are as follows to improve the Commercial Economics as a domain of vocational test. First, it is needed to change the subject name and its contents with a view to increasing the feature of the subject as an introductory course. So, its name and contents should be changed more business-oriented. Second, it is urgent to revise the subject contents for correcting its errors and disproportion, because it was adopted as a National Test Subject for the College Entrance from 2005 school year. Lastly, because the contents on business have the high merit for general education, we have to teach the business for not only students of business high school but also all students of general high school. Especially, personal finance literacy is needed for all people. 상업계열의 대표적인 입문과목인 상업경제 교과는 전반적인 교과내용 중에서 경제부분은 상대적으로 강조되고 있는 반면에, 비즈니스(경영)부분은 소홀히 취급되고 있다. 즉, 상업경제 교과는 그 영역을 나타내는 교과명칭에서부터 문제점을 내포하고 있음은 물론, 교과내용의 정확성이나 교과내용의 균형성 등의 측면에서 많은 문제가 발견되고 있다. 따라서, 이 연구의 목적은 상업경제 교과의 명칭의 타당성 여부와 정확성, 적합성 및 균형성이라고 하는 관점에서 상업경제 교과내용상의 문제점을 검토하고, 이러한 문제점에 대한 단기적, 장기적 대안을 제시하는 것이다. 상업경제 교과는 상업계 고등학교의 입문교과로서의 특성을 살릴 수 있는 방향으로 명칭과 내용이 개선되어야 한다. 아울러, 수능시험을 위해서 시급한 것은 현행 교과내용상 오류와 불균형을 시정하는 것이다. 나아가, 비즈니스에 관한 내용은 일반 교양교육적 가치가 높으므로, 상업교과가 상업계 고등학생뿐만 아니라, 모든 학생들에게 독립된 교과목으로 제공될 수 있는 길을 모색할 필요가 있다.

정수장에서의 소독능 개선사례

김재식,Kim, Jae-Sik 한국상하수도협회 2005 한국상하수도협회지 Vol.10 No.-

소결온도에 따른 0.7Mg₄Ta₂O₉-0.3SrTiO₃ 세라믹스의 마이크로파 유전특성

김재식,최의선,이문기,이영희,배선기,Kim, Jae-Sik,Choi, Eui-Sun,Lee, Moon-Kee,Lee, Young-Hie,Bae, Seon-Gi 한국전기전자재료학회 2005 전기전자재료학회논문지 Vol.18 No.6

The structural and microwave dielectric properties of $0.7Mg_4Ta_2O_9-0.3SrTiO_3$ ceramics with sintering temperature were investigated. All the sample of the $0.7Mg_4Ta_2O_9-0.3SrTiO_3$ ceramics were prepared by conventional miked oxide method and the sintering temperature was $1425\~1500^{\circ}C$. The hexagonal phase of $Mg_4Ta_2O_9$ and the cubic phase of $SrTiO_3$ were coexisted. The porosity of $0.7Mg_4Ta_2O_9-0.3SrTiO_3$ ceramics were reduced with increasing sintering temperature. In the case of $0.7Mg_4Ta_2O_9-0.3SrTiO_3$ ceramics sintered at $1475^{\circ}C$, dielectric constant, quality factor and temperature coefficient of resonant frequency were 14.51, 82,596 GHz and $-3.14\;ppm/^{\circ}C$, respectively.

실업교원의 양성, 임용 및 재교육 체제의 개선방안

김재식,이용환,정남용 한국농·산업교육학회 2001 농업교육과 인적자원개발 Vol.33 No.3

The purpose of this study was to suggest directions for restructuring the pre-service, recruitment, in-service education of vocational teachers. This study was carried out through reviewing extensive literature, surveying opinions from members in the Provincial Offices of Education, professors in vocational teacher training institute, teachers in the vocational high schools, and asking opinions from a panel of experts. The major findings in this study were 1) In relation to pre-service, it is necessary to divide a role of vocational teacher training institute, to develop a competency-based curriculum based upon professional vocational teacher standard, and to introduce emergency certification about new demand fields. 2) In relation to recruitment, it is necessary to give an additional score to mid-career entrants and vocational qualification holders in recruitment exam, to introduce practical exam about vocational subject, to execute notice system about demand fields, and to control vocational teacher's supply-demand in the whole nation. 3) In relation to in-service education, the Ministry of Education administrate and finance support to enhance the vocational teacher's ability Based upon the results of this study, the researchers make some recommendations for policy execution and further research.

A Direction-Finding Antenna Inserted into the Surface of Cylindrical Conductor Body

김재식 한국전자파학회 2022 Journal of Electromagnetic Engineering and Science Vol.22 No.4

In this letter, a direction-finding (DF) antenna inserted into the surface of a cylindrical conductor body, with the conductor material in front of the antenna, is presented. To minimize a gain reduction in the axis direction of the cylindrical conductor, an aperture of an openended waveguide antenna is modified, and the conductor body is deformed. The antenna is operated at the X-band, and its direction finding performance using an amplitude comparison method is analyzed. To verify the validation of the performance of the antenna, the analyzed results are compared to the measurement results.