• Biotechnology and Bioprocess Engineering:BBE
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• 제7권6호
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• pp.357-361
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• 2002

Continuous production of lactic acid from glucose by Lactobacillus rhamnosus with cell recycling using an acoustic cell settler was carried out. The performance of the system, such as the concentration of cell and product were compared with the control experiment without recycling. The acoustic settler showed cell separation efficiency of 67% during the continuous operation and the cell concentration in the fermentor with recycle exceeded that of the control by 29%. Com-pared with the control, tactic acid production was increased by 40%, while glucose consumption was only increased by 8%. The higher value of lactic acid production to substrate consumption (Yp/s, product yield coefficient) achieved by cell recycling is interpreted to indicate that the recycled cell mass consumes less substrate to produce the same amount of product than the control Within system environmental changes due to the longer mean cell residence time induced the cells maintaining the metabolic pathways to produce Less by-Product but more product, lactic acid.

• 펄프종이기술
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• 제47권6호
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• pp.73-80
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• 2015

Corn stalk is the lignocellulosic biomass, which remain as leftover after harvesting. To use the corn stalk as raw material for paper industry, soda pulping was applied. In chemical compositional analysis, extractive contents of corn stalk (45.1%) was higher than hardwood. With corn stalk pith, soda pulp yield was 25.3% at 10.6 Kappa number, but 39.5% yield with 14.8 Kappa number for corn stalk rind. Higher extractives content in pith is one of the reason for lower pulp yield than rind. Pith pulp fibers had higher fines content than rind pulp. Pith parenchyma cell was removed as fines during pulping or washing process, which caused the lower yield. To use the corn stalks as a raw material for paper making, de-pith process is essential for higher pulp yield and longer pulp length.

• 한국미생물·생명공학회지
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• 제26권3호
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• pp.213-220
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• 1998

글루타치온 생산에 필요한 ${\gamma}$-glutamylcysteine synthetase와 glutathione synthetase 효소의 활성을 위한 ATP 재생산계에 대하여 연구하였다. 글루타치온 합성용 효소를 생산하는 E. coli TG1/pDR7${\alpha}$의 최적 배양하였으며 이때 글루타치온의 생산농도는31 mg/g wet cell이었다. 빵효모를 이용한 글루타치온의 생산수율은 acetate kinase보다 낮았으나, 경제성의 면에서는 더 우수할 것으로 판단된다. ATP 재생산계로 빵효모가 Saccharomyces cerevrsiae ATCC24858보다 더 우수함을 보였다. ATP농도 5mM에서 cysteine에 대한 글루타치온의 생산 수율은 36%이었다. Cysteine의 소모에 의한 글루타치온 생산 제약을 피하기 위하여 cysteine을 반응 2시간에 추가 공급함으로써 글루타치온 생산수율을 1.91배 증가시켰다. 다양한 기질 추가 실험 결과에 의해 빵효모에 의한 ATP재생산계가 유효하고, 14mM이상의 글루타치온 농도에서는 산물저해 현상이 있는 것으로 나타났다.

• Asian Pacific Journal of Cancer Prevention
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• 제15권21호
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• pp.9335-9339
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• 2014

Background: To determine the frequency of primary circulating prostate cells (CPC) detection according to age and serum PSA levels in a cohort of men undergoing screening for prostate cancer and to determine the diagnostic yield in those men complying with the criteria for prostate biopsy. Materials and Methods: A prospective study was carried out to analyze all men evaluated in a hospital prostate cancer screening program. Primary CPCs were obtained by differential gel centrifugation and detected using standard immunocytochemistry using anti-PSA, positive samples undergoing a second process with anti-P504S. A malignant primary CPC was defined as PSA+ P504S+, and a test positive if 1 cell/4ml was detected. The frequency of primary CPC detection was compared with age and serum PSA levels. Men with a PSA >4.0ng/ml and/or abnormal rectal examination underwent 12 core prostate biopsy, and the results were registered as cancer/no-cancer and compared with the presence/absence of primary CPCs to calculate the diagnostic yield. Results: A total of 1,117 men participated; there was an association of primary CPC detection with increasing age and increasing serum PSA. Some 559 men underwent initial prostate biopsy of whom 207/559 (37.0%) were positive for primary CPCs and 183/559 (32.0%) had prostate cancer detected. The diagnostic yield of primary CPCs had a sensitivity of 88.5%, a specificity of 88.0%, and positive and negative predictive values of 78.3% and 94.9%, respectively. Conclusions: The use of primary CPCs for testing is recommended, since its high negative predictive value could be used to avoid prostate biopsy in men with an elevated PSA and/or abnormal DRE. Men positive for primary CPCs should undergo prostate biopsy. It is a test that could be implemented in the routine immunocytochemical laboratory.

• 한국환경보건학회지
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• 제19권2호
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• pp.23-33
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• 1993

The anaerobic digestion of organic synthetic wastewater in anaerobic fluidized bed bioreactor (AFBBR) and anaerobic fluidized packed bed bioreactor (AFPBBR) was studied. This study was conducted to evaluate efficiency and reliability of two reactor. Experiment was performed to find the effect of upflow rate with AFBBR and the height of packed bed with AFPBBR. As a result, this program obtained several conclusion. These are given as follows: As applied the upflow rate increased in AFBBR the produced volume of biogas increased, while the gas production and COD removal decreased at above 0.3 m$^3$/h. When a upflow rate is 0.4 m$^3$/h in AFBBR the volatile suspended solid (VSS) became significantly increased. At an organic loading rate from 0.1 to 0.4 of upflow rate in AFBBR, the methane yield was 1.5584 m$^3$CH$_4$/kgCOD removed, and the observed cell yield coefficient was 0.0933 gVSS/gCOD. In case of AFPBBR, the results showed also that 20 cm of height of packed bed was superior to other in the aspect ot biogas production, the content of methane and COD removal. At 20 cm of height, the profile of microorganisms was stable, while at 30 cm the VSS of effluent became higher than AFBBR. Though COD removal of AFPBBR increased with packed bed, COD removal deteriorate with over packing because the loss of pressure became higher in the reactor. At an organic loading rate from 20 to 40 cm of packed bed in-AFPBBR, the methane yield was 2.5649 m$^3$CH$_4$/kgCOD removed, and the observed cell yield coefficient was 0.0506 gVSS/gCOD. Based upon the results obtained, it is suggested that AFBBR and AFPBBR is the most effective conditions at 0.3 m3/h of upflow rate, the 20cm of packed bed, respectively. The rate constant are summarized as follow:

• 공업화학
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• 제18권2호
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• pp.162-167
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• 2007

본 연구에서는 Clostridium beijerinckii Donker 1926을 이용한 연속식 혐기성 소화공정에서 수소 생산과 동력학적 특성을 고찰하였다. 기질은 glucose를 사용하였고, 0.5, 0.25, 0.125일의 체류시간 (hydraulic retention time, HRT)에서 실험이 이루어졌으며, 모든 HRT의 조건에서 탄산화물은 99% 이상의 제거효율를 나타내었다. 체류시간이 짧을수록, COD 제거율은 낮은 반면에, 전체 가스 중에서 수소 가스 함량과 수소 발생량이 높게 나타났다. 또한, 정상상태에서, 증식 수율과 수소가스 생성 수율은 각각 0.27 g-VSS/g- glucose, 0.26 L/g-glucose로 나타났다. 본 실험에 사용된 균주를 glucose와 같이 당 성분이 함유된 폐수처리에 적용하면 수소를 생산할 수 있으며, 이러한 실험 결과들을 잘 활용하면 대체에너지로서, 실제적인 수소가스 생산 시스템에 적용할 수 있을 것이다.

• Asian-Australasian Journal of Animal Sciences
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• 제18권8호
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• pp.1098-1104
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• 2005

The trial was carried out on twenty-one Friesian cows at the end of eight months gestation, nine multiparous and twelve primiparous; allocated into three groups (1 control, 2 and 3 experimental). The same diet was administred to all three groups before partum (12.8 kg DM/head/day) and after partum (18.8 kg DM/head/day). The cows in groups 2 and 3 received two different daily quantities of amino-acid chelated chromium (0.6 and 1.2 mg Cr/kg DM) from 4 weeks prior to presumed parturition to 6 weeks after. The milk yield control was carried out at 15, 30, 42 and 60 days. All animals were immunised two weeks prior to the presumed parturition and two weeks after with the following antigens: ovalbumin and brucellergene. Blood samples were collected weekly to monitor humoral and cell-mediated immune responses. When analysing the results of antibody immunity (ovalbumin) in the sixth blood collection both treated groups significantly increased compared to group 1 (0.5230 and 0.4536 vs. 0.1812 OD; p<0.05). The results of the cell-mediated immune response (brucellergene) had significant differences (p<0.10) in correspondence to the third (between group 2 and control) and the fifth (between groups 3 and 2) blood collection. Significant differences in fat corrected milk were observed at 42 days between group 3 and the other two groups (31.01 vs. 26.99 and 28.66 kg/d, p<0.05) and at 60 days between group 3 and control (30.88 vs. 26.69 kg/d, p<0.05). Before partum and at partum a positive immune response was obtained with a lower dose of chromium. After partum a positive immune response, anti-OVA indicator, was obtained with the higher dose of chromium while, $\gamma$-IFN indicator, with the lower dose. A significant increase of the milk yield resulted at both 42 and 60 days with the highest level of chromium.

• 미생물학회지
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• 제36권1호
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• pp.69-73
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• 2000

Chicory 뿌리에서 Arthrobacter sp. A-6를 배양하여 inulin fructotransferase를 생산하였을 매 균주의 성장속도, 효소의 생산성을 검토하였다. 가공된 치커리 뿌리는 inulin fructotransferase의 crude enzyme solution으로 처리하였을 때 생산되는 di-fructofuranose dianhydride(DFA III)의 양을 chicory 뿌리의 가공방법에 따른 차이를 비교하였다. 우선 standard 배지에서 생산된 효소액으로 10%의 inulin이 포함된 standard inulin용액을 처리하면, 1.14mg/ml의 DFA III가 생산되었다. Chicory뿌리의 전처리방법에 따라, 같은 조건으로 반응을 진행시키는 실험을 통해 각 배지에서의 생산효율을 비교하였다. Chicory뿌리를 washing과 extraction과정을 거치지 않고 그대로 반응시켰을 경우, 2.29 mg/ml의 DFA III가 생산되어 생산성이 가장 높았는데, 이는 세척과정에서 inulin이 유실되지 않으므로, 기질로 작용하는 inulin의 양이 가장 높은 데 기인하는 것으로 생각된다.

• Journal of Veterinary Science
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• 제22권6호
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• pp.74.1-74.13
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• 2021

Tissue engineering has been extensively investigated and proffered to be a potential platform for novel tissue regeneration. The utilization of mesenchymal stem cells (MSCs) from various sources has been widely explored and compared. In this regard, MSCs derived from bone marrow have been proposed and described as a promising cell resource due to their high yield of isolated cells with colony-forming potential, self-renewal capacity, MSC surface marker expression, and multi-lineage differentiation capacities in vitro. However, there is evidence for bone marrow MSCs (BM-MSCs) both in vitro and in vivo from different species presenting identical and distinct potential stemness characteristics. In this review, the fundamental knowledge of the growth kinetics and stemness properties of BM-MSCs in different animal species and humans are compared and summarized. Finally, to provide a full perspective, this review will procure results of current information studies focusing on the use of BM-MSCs in clinical practice.

• 한국약용작물학회지
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• 제12권2호
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• pp.141-148
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• 2004

Two compounds from Gomisin N and Gomisin A were isolated from the fruits of Schizandra chinensis Baillon. The highest extraction yield as 21.36% was observed in the ethanol extract, compared to the yield obtained form the water extract. The extraction yields of the single compounds were measured to be 0.13 and 0.014 Gomisin A and Gomisin N, respectively. Approximately, 90% of the growth of human stomach adenocarcinoma cancer cells was inhibited after adding 1.0 g/l of the ethanol extract. The growth of the human normal lung cell was limited to 24% after adding the ethanol extract. The water extract lowered the specific secretion of $TNF-\acute{a}$ and IL-6 from T cells, $10.3{\times}10^{-4}\;pg/cell\;and\;12.1{\times}10^{-4}\;pg/cell$, respectively, compared to the ethanol extracts. On the other hand, a treatment with the ethanol extract increased the specific secretion of $TNF-\acute{a}$ and IL-6 from human T cells, to $11{\times}10^{-4}\;pg/cell\;and\;14.3{\times}10^{-4}\;pg/cell$, respectively. The crude ethanol extract had the highest effect on the differentiation of human promyelocytic leukemia cells compared to the other extracts and Gomisin A and N. In general, the biological activities of the extracts gradually decreased as the purification process proceeded, which suggests that higher immunostimulatory activities can be maintained by adding the crude extracts of the fruits rather than by adding a single compound.