• 생명과학회지
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• 제17권9호통권89호
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• pp.1260-1265
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• 2007

자석으로 분리가 가능한 ${\alpha}-Amylase$가 코팅된 나노고분자를 제조하여 녹말의 분해공정에 활용하였다. 본 연구에서 개발된 고정화 효소의 안정성은 크게 증가하여 상온에서 200rpm으로 교반하면서 보관한 경우 30일 동안에 92.7%의 활성도를 유지하였다 . 고정화 효소를 자석을 이용하여 재사용한 경우 10 회 동안 사용했을 경우 95.2%의 활성도 회수율을 보 여 효소의 재사용 가능성을 확인시켜 주었다 . 고정화 효소 0.5mg을 사용하여 녹말 분해 공정 에 활용하였을 때 2 ml의 40 g/l 녹말 용액을 40분만에 완전히 분해 시켰다, 이러한 고정화 효소를 사용하여 연속 효소반응기를 개발하여 녹말 분해공정에 활용한 결과 체류시간을 1시간으로 하였을 때 녹말 30 g/l를 76% 분해시켜 산업적으로 활용 가능성을 보여 주었다.

• The Plant Pathology Journal
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• 제22권4호
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• pp.329-333
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• 2006

Two distinct and stable isolates of Barley mild mosaic virus(BaMMV) designated as Naju82-S(severe) and Naju82-M(mild) were obtained. These two isolates differed in their symptomatology, virus transmission characteristics and cultivar specificity at various temperature. Thus, these isolates were referred to as strains in this study. BaMMV Naju-S strain showed severe mosaic symptoms accompanied by necrosis on the infected leaves. Naju82-S strain is more virulent demonstrated by shorter incubation period and relatively high virus concentration than Naju82-M strain. Five Korean cultivars were tested for their pathogenicity to different strains based on the rate of infection. Results showed that infection rate of cultivars to both strains did not significantly differed from each other. However, under different temperatures, the pathogenicity on the two cultivars such as cultivars Hopumbori and Sessalbori were significantly affected. Hopumbori was moderately resistant to both strains at $10-12^{\circ}C$ and susceptible at $15-18^{\circ}C$. Similarly, Sessalbori was moderately resistant at $10-12^{\circ}C$ to both strains but distinctly differentiated at $15-18^{\circ}C$ wherein it was resistant to mild strain and highly susceptible to severe strain. Other cultivars including Baegdong, Jinyangbori and Neahanssalbori consistently showed susceptible reaction to both strains at varying temperatures tested in this study.

• 한국가축번식학회지
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• 제9권2호
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• pp.105-112
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• 1985

This research was carried out to investigate the optimal conditions ssociated with the RIA procedures such as a bridging phenomena, prozone effects and a new separation methods etc. The results obtained were summarized as follows: 1. The lgG fractions of donkey anti-rabbit IgG sera were purified by Protein-A-Sepharose affinity column, which indicates that Protein-A an affinity for IgG class of donkey antiserum. 2. In coating the IgG fraction on polystryene tubes, incubation conditions made no differences between 2 hr at room temperature and overnight at 4$^{\circ}C$. 3. There were no significant differences between 1st antibody-coated tube and 2nd antibody-coated tube as a separation method when compared in terms of reproducbility. A better reproducibility may be expected if the titers of 1st antibody for the progesterone to be assayed and of corresponding 2nd antibody are reasonably high. 4. The titers of anti-progesterone antibody for 3H-progesterone and progesterone-11HS-125I were 1:300 and 1:700 in liquid-phase, and 1:100 and 1:300 in solid-phse for the separation methods. 5. A bridging phenomena in which a standard curve is long and shallow were observed when progesterone-11HS-125I was used for the tracer, but not in 3H-progesterone. 6. A prozone effect in a solid-phase system, especially 1st antibody-coated tube method was observed which the degree of inhibition was significantly different although zero bindings look the same. In this case, the titration curve should be made both in the absence and in the presence of a, pp.opriate amount of competiter, standard, respectively.

• 한국균학회지
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• 제14권4호
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• pp.273-280
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• 1986

Rhizorus oryzae의 생장 및 autolysis에 따른 여러가지 autolytic enzymes의 활성도 변화와 이 autolytic enzyme system을 이용한 원형질체 생성에 관하여 조사하였다. Autolytic·phase의 culture filtrate 내에 함유된 autolytic enzyme은 Rh. oryzae 균사체로부터의 원형질체 생성에 효율적인 세포벽 분해효소로 작용하였으며 Autolytic enzyme중 원형질체 생성은 proteolytic 및 chitosanase activity와 가장 긴밀하게 관련되어 있었다. 이와같은 autolytic enzyme을 이용한 원형질체 생성은 10시간 배양한 균사체에 0.5M mannitol을 사용하였을 때 최고의 수율을 보였으며 원형질 생성의 최적온도 및 pH는 각각 $25{\sim}30^{\circ}C$ 및 $6.0{\sim}6.5$로 나타났다 한편 18시간 배양된 균사체를 osmotic stabilizer와 aut-olytic enzyme을 1 : 1이 되도록 처리하고 5시간 동안 $30^{\circ}C$에서 incubation하여 얻은 원형질체를 주사전자현미경으로 조사한 결과 효소에 의하여 가수분해되는 세포벽 주변으로부터 원형질체가 형성되는 것을 확인하였다.

• Journal of Dairy Science and Biotechnology
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• 제30권2호
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• pp.83-92
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• 2012

This study was performed for analyzing the general composition and the change in the quality of soymilk-derived yogurts manufactured by adding skim milk and whey powder to soymilk heat-treated at $95^{\circ}C$/5 min and $120^{\circ}C$/10 min, respectively. 1. During the storage of soymilk yogurt, the concentrations of total solids, protein, fat, and lactose slightly decreased, whereas viscosity, content of ash and NPN, and the number of lactic acid bacteria remained unchanged. 2. The pH and titratable acidity changed rapidly in all soymilk yogurts after 3 h of incubation. 3. We found $7.8{\times}10^8$ lactic acid bacteria in the control sample, $4.7{\times}10^8$ and $5.02{\times}10^8$ in soymilk yogurt with skim milk, respectively, and $5.9{\times}10^8$ and $5.5{\times}10^8$, respectively in soymilk yogurt with whey powder according to degree of heat treatment with $95^{\circ}C$/5 min and $120^{\circ}C$/10 min. 4. The viscosity of yogurt samples became lower as the heat treatment increased in temperature and in the length of time. 5. The value of sensory evaluation was relatively high in soymilk yogurt with the added skim milk, which was heat-treated $95^{\circ}C$/5 min; however, the value was significantly lower than that of the control sample. 6. Lactose, glucose, and galactose were detected in all samples because lactose is degraded into glucose and galactose within 3 h of inoculation.

• 미생물학회지
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• 제31권1호
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• pp.63-71
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• 1993

A xylanase (xylanase I) was purified 11.9-fold from the culture filtrate of Trichoderma koningii ATCC 26113 by the column chromatography on Sephadex G-75, SP-Sephadex C-50, DEAE-Sephadex A-50 and Sephadex G-50 with an overall yield of 8.2%. The molecular mass determined by gel filtration and sodium dodecyl sulfate polyacrylamide gel electrophoresis was found to be a monomeric polypeptide of ca. 35 kDa. The isoelectric point of the enzyme was estimated to be 9.3. The optimal reaction pH and temperature are 5.8 and 55.deg.C, respectively. The enzyme is stable up to 60.deg.C, while 78% of its activity is lost after the incubation for 10 min at 70.deg.C. The enzyme hydrolyzes sylan with relatively high activity, as well as carboxymethyl cellulose and avicel. The $K_{m}$ values of the enzyme for oat-spelf sylan, larchwood xylan and Avicel were 3.5, 1.6 and 10. 1 mg/ml, respectively. The enzyme hydrolyzed oat-spelt sylan to sylose, sylobiose, sylotriose and arabionoxylobiose, while it degraded larchwood xylan to xylose, xylobiose, xylotriose and arabionoxylobiose, while it degraded larchwood xylan to xylose, xylobiose and xylotriose as the major products. The hydrolysis patterns indicate that xylanase I is endo-enzyme.e.

• KSBB Journal
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• 제11권6호
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• pp.636-641
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• 1996

김치발효 중에 분리한 젖산균의 일종인 Leueonos toe sp. KY -002를 이용하여 mannitol 생산 특성을 검토하였다. 여러 가지 탄소원 중에서 설탕과 과당만 이 mannitol 생성의 기질로 이용되었고, 50 g/L 과 당을 기질로 사용할 경우 mannitol 생산성이 가장 좋 았으며 이때 최대수율은 초기과당 기준으로 약 52% 이었다. 초기 탄소원이 고갈펼 경우, 생성된 manmtol이 다시 기질로 이용되지 않았고, 100 ~ 250 g/L 이상의 고놓도 기질농도에서는 수율이 30% 이하 수 준으로 낮았으나, 모든 실험조건에서 다른 탕알콜류 를 부산물로 생성하지 않았다. Mannitol 생성에 미 치는 여러 가지 배양인자들을 검토한 결과, 질소원 으로 yeast extract가 가장 우수하였고, 무기인산염 은 10 g/L 농도 벙위까지 농도가 높을수록 유리하 였으며, 금속이온과 NaCI, KCl 등의 엽류의 천가는 m mannitol 발효에서 역효과를 나타내였다. 몇 가지 vitamin류의 첨가에 의해 mannitol 생산을 촉진시 킬 수 있었는데, 특히 nicotinic acid의 첨가에 의해 발효놓도를 16% 증가시킬 수 있었다. 배양환경중 온도는 $35^{\circ}C$, 초기 pH는 6이 최적이었다.

• 생명과학회지
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• 제21권1호
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• pp.134-140
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• 2011

대전일원의 유류오염 지역의 토양으로부터 원유를 단일 탄소원으로 이용하는 총 145균주를 순수분리 하였고, 이중 생물 계면활성제 생성능이 가장 우수한 한 균주를 최종 선별하여 형태 및 생리 생화학적 특성을 조사하고 16S rRNA 염기서열을 분석을 통하여 동정한 결과 Pseudomonas sp.로 확인되어 Pseudomonas sp. Z1이라 명명하였다. 최종 선별된 Pseudomonas sp. Z1은 클로람페니콜과 암피실린 등의 항생제와 리튬, 망간, 바륨 등의 중금속에 대해 강한 내성을 갖고 있었고, 최적 온도와 pH는 각각 $30^{\circ}C$와 pH 6.0-7.0으로 확인되었다. Pseudomonas sp. Z1이 생성하는 생물 계면활성제는 배양 10시간 이후부터 배양액의 표면장력이 급격히 감소해, 배양 21시간 후에 최대 28 dyne/cm까지 감소되었고, 2% 이상의 NaCl을 첨가한 경우 배양액의 생물계면활성제의 활성이 감소하였다.

• Journal of Microbiology
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• 제45권4호
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• pp.333-338
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• 2007

Intracellular NADH:quinone reductase involved in degradation of aromatic compounds including lignin was purified and characterized from white rot fungus Trametes versicolor. The activity of quinone reductase was maximal after 3 days of incubation in fungal culture, and the enzyme was purified to homogeneity using ion-exchange, hydrophobic interaction, and gel filtration chromatographies. The purified enzyme has a molecular mass of 41kDa as determined by SDS-PAGE, and exhibits a broad temperature optimum between $20-40^{\circ}C$, with a pH optimum of 6.0. The enzyme preferred FAD as a cofactor and NADH rather than NADPH as an electron donor. Among quinone compounds tested as substrate, menadione showed the highest enzyme activity followed by 1,4-benzoquinone. The enzyme activity was inhibited by $CuSO_4,\;HgCl_2,\;MgSO_4,\;MnSO_4,\;AgNO_3$, dicumarol, KCN, $NaN_3$, and EDTA. Its $K_m\;and\;V_{max}$ with NADH as an electron donor were $23{\mu}M\;and\;101mM/mg$ per min, respectively, and showed a high substrate affinity. Purified quinone reductase could reduce 1,4-benzoquinone to hydroquinone, and induction of this enzyme was higher by 1,4-benzoquinone than those of other quinone compounds.

• Fisheries and Aquatic Sciences
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• 제25권5호
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• pp.264-275
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• 2022

A non-destructive environmental DNA protocol for the genetic analysis of sea cucumber (Apostichopus japonicus) resources DNA was established. Among the several commercial DNA extraction kits, the DNeasy^® Plant Mini Kit was selected as the best choice to obtain the high-quality genomic DNAs from the mucous sea cucumber. As the temperature and incubation time increased, the amount of extracted environmental DNA was also large, but it was judged that the increased amount did not affect as much as 2-3 times. Therefore, these conditions were not considered to be the main factors to consider in actual environmental DNA extraction. However, the amount of seawater relative to the size of the sample was judged as a major consideration, and a sufficient amount of environmental DNA for analysis was secured when stored within 1 min while stirring the volume of seawater corresponding to the total sea cucumber weight (g). In securing the environmental DNA of sea cucumbers, the mortality rate of sea cucumbers in all experiments was 0, and it was judged that the effects of sea cucumbers were not significant through this treatment. Through the results of this study, sea cucumber DNA research, which has been conducted in a destructive method, can be conducted non-destructively through environmental DNA analysis. Through this study, we have secured a standard protocol that can successfully extract the sea cucumber DNA through environmental DNA. It is not only excellent in terms of time and cost of traditional DNA analysis method currently used, but it is completely non-destructive in the ecosystem of the survey area. It is believed that the system can be transformed in a way that does not affect it. However, it is thought that various standard protocols should be established considering the characteristics of each type.