• 한국미생물·생명공학회지
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• 제25권4호
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• pp.427-433
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• 1997

Sludge Returned CMAS process was applied to treat the wastewater from electric accessory manufacturing company while this type of wastewater was usually treated by chemical process. This result show that the removal rate of TCOD was about 70-80% regardless of hydraulic retention time, On the contrary, the removal rate of BOD was abtained in a range of 77-92% depending on hydraulic retention time. In order to remove more than 80% of organic materials with the proposed process, the F/M ratio should be maintained below 0.17. In this case, the calculated value of organic removal rate, Km, was calculated to be 1.26 hr$^{-1}$, and the ratio of cell synthesis/total energy was 0.32 and 0.26 for COD and BOD base, respectively. The yield coefficient was calculated to be 0.242 and the half velocity coefficient was 0.3 hr$^{-1}$. The value of endogenous respiration coefficient was 0.02 hr$^{-1}$. The measured effluent BOD concentration, MLSS concentration in aeration tank, oxygen uptake rate, and sludge production were matched relatively well with the calculated values using above coefficients, In order to optimize the dewatering of sludge, the hydraulic retention time was recommended to be 15. 6 hrs. These results indicate that the wastewater from an eletric accessory manufacturing company can be treated safely with a biological process.

• Asian-Australasian Journal of Animal Sciences
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• 제17권4호
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• pp.554-559
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• 2004

The objective of the present study was to investigate the accuracy of mastitis diagnostic indicators for different dairy goat breeds. Biweekly milk samples were collected from individual half mammary gland of seven Saanen and seven Alpine dairy goats in the period of 40 to 120 days in milk. With threshold value set at 2.8 and 3.1 for Alpine and Saanen dairy goats, respectively, log (SPC) offered good sensitivity (0.89, 0.93), specificity (0.88, 0.95), positive predictive value (0.75, 0.85) and negative predictive value (0.95, 0.98) as a mastitis diagnostic tool. The correlations of log (SPC) with milk yield, log (SCC), ALP, LDH, $Na^{+}$, $K^{+}$ and EC were significant in Saanen dairy goats (p<0.05), with the highest correlation coefficient (0.653) existing between log (SPC) and log (SCC). The correlations of log (SPC) with milk yield, milk fat, milk protein, log (SCC), $Na^{+}$, $K^{+}$, EC were significant in Alpine dairy goats (p<0.05), with the highest correlation coefficient (0.416) existing between log (SPC) and log (SCC). There were different best-fit regression equations with different multiple diagnostic indicators for Saanen and Alpine dairy goats. In conclusion, different breeds of dairy goats may have to adapt different mastitis diagnostic parameters for a better diagnosis.

• 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:

• Journal of Microbiology and Biotechnology
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• 제11권6호
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• pp.1055-1060
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• 2001

Experimental data for the on-line estimation of cell concentration and growth rate are presented. For this purpose, we utilized the on-line calculation of the oxygen uptake rate (OUR), which was derived from a liquid phase dynamic mass balance for the oxygen during the active growth phase in cyclosporin A (CyA) fermentation. The cell yield coefficient, based on the oxygen $(Y_{x/o})$for both suspended and immobilized cells of Tolypocladium inflatum, was estimated as $1.9 gDCW/gO_2$ from a very good linear correlation between the cell mass produced and the total oxygen consumed. The calculated yield showed a good agreement with the value of $(Y_{x/o})$ generated from the correlation between the cell growth rate and the oxygen uptake rate. In addition, further experimental data are given, which were also applied to determine the specific oxygen uptake rate of T. inflatum cells during the exponential phase of CyA fermentation. A theoretical basis for the analysis of these fermentation parameters is also provided.

• 한국미생물·생명공학회지
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• 제16권2호
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• pp.85-91
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• 1988

Ruminococcus albus와 Ruminococcus flavefaciens 두 균주를 사용하여 기질 cellulose로부터 균체량과 생성물 형성에 대해서 available electron balance를 적응한 에너지 효율이 검토되었다. 실험 결과로부터 진정수율(true growth yield) 값인 η$_{max}$, η$^{max}_{th}$ 두 값과 유지 계수값인 m$_{e}$ 값이 이론적 접근으로부터 얻어진 값들과 비교 검토되어졌다. 실험치는 $Y^{max}_{ATP}$=10.5g cells/mole ATP 값을 적용한 이론치와 비슷하므로 Ruminococcus albus, Ruminococcus flavefaciens의 $Y^{max}_{ATP}$ 값은 10.5와 비슷한 값을 갖는 것으로 사료되어진다.

• KSBB Journal
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• 제5권2호
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• pp.95-100
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• 1990

균주 K.fragilis에 의한 이눌린의 PEG/Dextran 수성 이상계 알콜발효실험에서 알콜발효특성, 알콜 및 이눌린의 분배특성에 미치는 PEG분자량. PEG농도, Dextran농도의 영향을 구명하여 보았다. Dextran농도 1내지 3wt%범위에서 에탄올 발효능과 에탄올 생산성은 PET분자량 증가에 따라 감소하였으며 균체수율과 균체생산성은 그 반대 경향을 나타내었다. PEG농도 6내지 10wt%범위에서 윗상에서의 에탄올 배수율은 아랫상의 Dextran농도가 증가할수록 감소하였다. 이눌린 분배계수는 PEG분자량 증가에 따라 미세하게 감소하였으며, PEG농도에 영향을 받는 이눌린 분배특성은 분배계수, 분배수율 및 분배비이였으며. Dectran농도 증가에 따라 분배계수와 아랫상에서의 이눌린 분배수율은 증가하는 반면 이눌린 분배비는 감소경향을 나타내었다.

• KSBB Journal
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• 제4권1호
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• pp.34-39
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• 1989

본 논문은 동물 세포의 대량 배양을 위해 연속 공법 방식인 Perfusion Continuous System을 도입해 의약적으로 중요한 EPO의 생산을 위한 생물 공학적인 자료들을 제고하고 있다. 이 System은 세포 증식 속도를 배지의 Perfusion 속도로 변화시킴으로써 조절시킬 수 있는 산소 소비속도와 밀접한 상관관계가 있음을 입증하며 이는 세포수의 직접 측정에 따른 오차 및 방법상의 문제를 정학히 측정할 수 있는 간접 변수, 즉 산소소비속도를 이용함으로써 제거할 수 있다. 특히 이 산소소비속도와 세포 성장 관계로 model로써 세포 증식을 예측함과 동시에 동물 세포 대량 배양을 위한 scale-up의 중요한 기초자료가 될 것이다. 지금까지 발표되지 않았던 동물 세포의 glucose에 대한 True growth yield와 maintenance coefficient값들의 측정은 동물 세포 성자관 유용 물질 생산을 위한 중요한 수율적 자료가 된다.한편 이 결과는 지금까지 미생물이나 광합성에서만 적용되었던 yield model이 Eukaryotes에서도 응용될 수 있음을 증명하고 있다. 이와 같이 perfusion system이 많은 장점을 갖고 있지만, 세포 성장에 따른 동력학적인 연구의 수행이 좀 더 요구되는 실정이며, 특히 Perfusion system을 설명할 수 있는 이론 및 cytostatic moel의 정립이 선행되어야 할 것이다.

• 수산해양기술연구
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• 제17권1호
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• pp.41-47
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• 1981

The characteristics of septic tank sludges were investigated and the kinetic coefficients in the aerobic biodegradation were evaluated from bach treatability tests. Using an unbiased statistical method, the estimated values, k (substrate removal rate coefficient) =0. 0175hr-1 at 17\ulcornerC, K. (Michaelis Menten constant) = 248mg/ e, a (cell yield coefficient)=0.625, and Kd (cell decay coefficient:' =0. 00192hr-1 were obtained based on biodegradable COD(mg/ \ulcorner) and volatile suspended solids(mg/\ulcorner). The relationship between COD and BOD, COD (mg/\ulcorner) =2. 1 BOD(mg/\ulcorner) +250, also was established for the septic tank sludges. Dilution was inevitable for the grit removal because of the high viscosity of the sludges. An aerobic activated sludge process rather than anaerobic processes was recommended for the removal of soluble organics after the removal of grit and suspended solids. A multi-stage activated sludge process was adapted for this highly concentrated and not easily-degradable waste. It was estimated that a four-stage activated sludge process would require 40 hours retention time compared to 92 hours for a single-stage process, 52 hours for a double-stage process, and 46 hours for a three stage process in order to achieve an effluent quality of 84mg/ e COD( 40mg/ e BOD) with about 4, OOOmg/ \ulcorner MLSS from an influent quality of I, 500mg/ t COD(714mg/.e BOD), while multi-stages beyond four stage would not save the required retention time significantly.

• Biotechnology and Bioprocess Engineering:BBE
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• 제9권1호
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• pp.12-16
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• 2004

Partitioning of human granulocyte-macrophage colony stimulating factor (hGM-CSF) was achieved in the aqueous two-phase systems (ATPSs) using a crude extract of transgenic tobacco cell suspension culture. This study examined the effects of polyethylene glycol (PEG) molecular weight and concentration and the effects of sodium phosphate concentration in different PEG/sodium phosphate systems on the partition coefficient, K. The best ATPS system was 5% PEG 8,000/1.6 M sodium phosphate after 2 h of incubation at room temperature. In this system, hGM-CSF was partitioned in the PEG-rich phase with a yield of 57.99% and K$\_$hGM-CSF/ of 8.12. In another system, 3% PEG 10,000/1.6 M sodium phosphate, hGM-CSF was also partitioned primarily in the top phase with a yield of 45.66% and K$\_$hGM-CSF/ of 7.64 after 2 h of incubation at room temperature.

• 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.