Earticle

본 연구의 목적은 생물막 유동층 반응기내에서 높은 유기물 부하를 처리하는데 있어 지지체에 부착된 미생울의 특성과 유기물의 처리효율을 조사하는데 있다. 실험은 글루코오즈를 주 기질로 한 합성폐수를 이용하여, 상향유속은 0.47cm / sec, 체류시간을 5시간, 운전 온도는 22±1℃, pH는 7±0.1로 일정하게 하고 유기물 부하를 10kgCOD/m3.day에서 80kgCOD/m3.day로 증가시켰을 때, 각각 95%, 73%의 높은 COD 처리효율을 얻었다. 고정 생물막 반응기에 사용된 Andrew의 유기물 제거율 모델을 본 생물막 유동층 반응기에 적용시켜본 결과, 실제 유기물 제거율과 예측한 유기물 제거율은 85% 정도로 일치하였다

A number of experiments were conducted in order to investigate the COD removal rate according to the biofilm thickness in a Fluidized-Bed Biofilm Reactor(FBBR). The following conditions were fixed during the experiments: superficial upflow velocity was 0.47cm/sec, operating temperature was 22±1℃ and pH was about 7±0.1. The synthetic wastewater based on glucose was used as a substrate. The COD removal efficiencies were shown as 73% and 95%, respectively, when organic loading rate was increased from 10kgCOD/m3.day to 80kgCOD/m3.day. Andrew's model of substrate removal rate which was commonly used in fixed-biofilm reactor was transformed and applied in this FBBR experiment to predict substrate removal rate and gave 85% agreement with the experimental values.

The production of bassinosteroid-like substances of two hybrid types of Korean rice, Jangseongbyeo, Taebackbyeo were investigated. The shoots at the maximum tillering stage were extracted and purified by solvent fractionation, silica gel adsorption chromatography Sephadex LH-20 chromatography, charcoal adsorption chromatography, Bondesil chromatography and HPLC of reverse phase, successively. Biological activities of each purification step were monitored by the rice lamina inclination test. Higher activities against the rice lamina inclination test in the each purification step showed that the shoots of two cultivars biosynthesize brassinosteroids. Two cultivars also showed a similar distribution of biological activities of endogenous brassinosteroids detected by HPLC

This study is to investigate the kinetics of anaerobic process, the effect of mass transfer on process, and the characteristics of the conventional anaerobic bioreactor, and develop new high efficiency bioreactor. In the new bioreactor wastewater containing highly concentrated organic materials, was treated without diluting wastewater. In this experiment the high COD removal rate (about 88%) and gas production(about 200l/d) was showed with short residence time(1.5 day). This performance is about 10 times as large as the conventional reactor.

This study thus looks into two treatment processess : i) Anaerobic digester coupled with hollow fibre membrane unit. Treatment of starch waste with anaerobic digester-membrane system was studied. 0.17u2 area of hollow fibre membrane unit of known pore size was immersed into laboratory-scale anaerobic digestion system. The pore size of membrane was varied from 0.03 to 0.15mum. The hydraulic retention time of anaerobic digester was varied from 1.5 to 10 days. The effect of hydraulic retention time on treatment efficiency was significant while effect of membrane size was not significant. The gas production was about 0.74㎥/kg COD treated. The COD removal efficient was about 80-95% depending on the hydraulic retention time. ii ) Crossflow ultrafiltration as post treatment to anaerobic filter. The effluent from anaerobic filter, which had a total COD in the range of 4,500-5,200 mg/L was treated by crossflow ultrafiltration units. The study conducted with different membrane pore size indicated that membrace with 1,000,000 molecular weight cut-off size gave a higher COD removal efficiency in the range of 83-87% while giving a study flux of 120-130L/u2 .h. A study was conducted to see the long term clogging effect of membrane also.

세균액화형의 a-amylose의 공업적 생산의 효율성을 높이기 위한 연구의 일환으로 제분공장과 도정공장의 분산물인 밀기울과 쌀겨를 이용하여 배양배지를 조성하고 B. subtilus와 A. oryzae 및 B. natto를 배양한 후 액화형 a-amylose의 활성을 조사한 결과 B. subtilus와 A. oryzae의 경우 순수배지와 비교하였을 때 큰 차이가 없었으나 B. natto의 경우 외밀기울에서 액화활성이 다른 대구조에 비하여 크게 나타났는데 순수 배지를 이용한 액화활성은 crude enzyme에서 27.3 unit/ ml이고, 최종 액화 활성은 1,255.8u / ml인데 반해 외밀기울을 이용한 액화 활성은 crude enzyme에서 256.0 unit/ ml이고, 최종 액화 활성은 10,700 unit 이었으며 최적 배양온도는 378℃이며 최적 배양액 pH는 6.8이었다. 그리고 정제된 효소의 분자량은 34,000dalton이었다. 이상의 결과로 보아 밀거울이 a-amylose의 공업적 생산을 위한 저렴한 기질로 사용될만한 가치가 있다고 사료된다.

The liquifying a-amylose production from B. subtilis, A. oryzae and B. natto using wheat and rice bran as low cost culture medium was investigated. Among 3 strains, B. natto showed heights productivity of a-amylose in the outer wheat bran medium. And the optimum culture condition is pH 6.8 and 37℃ for the production of a-amylose. The a-amylose activity of the crude enzyme and the purified enzyme are 256 unit/ml and 10,700 unit/ml, respectivitly. The a-amylose from B. natto cultrtured in outer wheat bran medium was purified into nearly a pure state(98.7%). And the molecular weight of the purified a-amylose was 34,000.

Diazotized chitin (CHITN) was synthesized reacting with NaN3 and HCl to alkaline hydrolyzed chitin for the support of immobilized enzyme. Immobilized B-glucosidase on diazotized chitin(CHITN-Gase) was produced reacting with glutaraldehyds as bifunctional reagent. CHITN-Gase activities were determined reacting with p-nitrophenol-B-D-glucopyranoside in plug flow reactor as a reference. Optimum temperature, optimum pH, reaction constant and deactivation rate were determined with variation of flow rate and H/D. The particle size of immobilized enzyme in the best was, 35 mesh (CHITN35-Gase). The optimum conditions of immobilized enzyme were in temperature and 5.0 in pH. Diameter and flow rate of plug flow reactor in the best was 8.5mm in diameter and 0.8ml/min in flow rate. Reaction constant was mainly influenced by electrostatic force. The best glucose hydrolizing activities of CHITN3 5-Gase was 3.3410-5 M/1. while that of native-B-glucosidase was 2.4410-5 M/1.

The structural properties of cellulose are significantly changed with the progress of hydrolysis reaction. The effects of changes on such properties of cellulosic substrate as crystallinity, amicessibility of enzyme to the active site of cellulose surface, and particle size on the kinetics of enzymatic hydrolysis have been studied. Among those physical studies, the apparent surface active site of cellulose particle was found to have the most significant effect on the hydrolysis kinetics. Based on the experimental results, the adsorption affinity of enzyme and hydrolysis rate were mainly influenced by the surface roughness of cellulose particle. The extent of accesssible active site may be expressed as the change of particle diameter. The Langmuir isotherm was proposed in terms of enzyme activity to explain the actual action of enzyme protein.

섬유소 물질을 유용한 자원으로 전환시키기 위하여 섬유소 분해요소를 상요하여 가수분해 반응을 시킬 때 섬유소의 구조적 특성, 섬유소-효소계의 상관성, 가수분해 저해효과, 섬유소 분해효소의 불활성화 등에 의하여 섬유소 가수분해 반응 속도에 상당한 영향을 주는 것으로 알려져 있다. 가수분해 반응이 진행함에 따라 높은 결정성을 가진 섬유소인 Avicel PH 101의 결정화도는 서서히 증가하였으며 무정형이 많은 Solka Floc BW 40은 반응초기에 급격한 증가를 보여주었고 실험적으로 결정성 부분과 무결정성 부분이 동시에 분해됨을 알 수 있었으며, 반응 초기에 급격한 효소의 흡착이 일어나며 반응이 진행함에 따라 서서히 탈착됨을 볼 수 있었다. 반응 생성물인 글루코오스와 셀로바이오스는 초기 가수분해 반응속도에 상당한 저해효과를 주며 또한 생성물의 농도가 증가할수록 효소 흡착량이 감소함을 알 수 있었다. 섬유소 분해요소의 불활성도는 반응시간에 따라 지수 함수적으로 변화함을 실험적으로 알 수 있었다. 셀로바이오스의 초기 가수분해 반응속도는 상대적으로 높은 B-glucosidase의 활성도에 의해 비교적 높은 셀로바이오스의 농도(5-10mg/ ml)에서도 기질의 저해효과가 적음을 볼 수 있었다.

Enzymatic cellulose hydrolysis depends on the several factors such as the structural features (CrI, particle size and surface area, etc.), the nature of cellulase enzyme system, the inhibitory effects of products, and enzyme deactivation. At the presence of products on the initial hydro- lysis rate of cellulose, cellobiose has more severe inhibitory effect than glucose. Othewise, the inhibition effect of products for adsorbed enzyme is related to the glucose and cellobiose conentration hyperbolically. Enzyme deactivation of FPA and B-glucosidase were expressed by exponential decay profile.

The quantitative effects of molecular weight and concentrations of two phase-forming polymers-polyethylene glycol and crude dextran on the two phase extractive ethanol fermentation were investigated using a Box-Wilson central composite protocol. The regression model obtained was used in order to determine optimum compositions of aqueous two phase system. In the aqueous two phase extractive ethanol fermentation of Kluyueromyces fragilis CBS 1555 with Jerusalem artichoke juice, it was found from the regression model that the variables influenlcing on ethanol fermentation were PEG concentration, time, Dx concentration, and PEG molecular weight strongly in order. The interaction of PEG concentration and PEG molecular weight was also found, and the effect of PEG concentration decreased with increase in molecular weight of PEG. The ethanol concentration incresed with increase in molecular weight of PEG, and with decrease in concentration of PEG. In conolusion, maximum concentration of ethanol produced was obtained at the following compositions; PEG MW 20000, Dx concentration ranged from 4% to 5%, and PEG concentration ranged from 3% to 7%.

본 연구에서는 PV에 아나베나세포를 흡착법에 의하여 고정화하였다. 진탕배양하면서 고정화한 겨웅에 비하여 반응기속에 배양액을 trickling 시키면서 배양하고 고정한 경우 높은 세포밀도를 보였다. PV에 고정화한 세포들의 생리적 활성을 조사한 결과 광합성능이 암처보관시에 free cell에 비하여 안정됨을 보였고, msx처리시의 암모니아의 방출도 증가하였다. 뿐만 아니라 고정화한 세포에서 광합성활성의 온도에 대한 내성이 증가하였으며 nitrogenase 효소 활성도 free cell에 비하여 크게 증가하였다. nitrogenase효소에 의한 연속적인 광수소발생을 조사한 결과 혐기적 조건하에서 연속적으로 수소가 생성됨을 볼 수 있었는데 그 발생양은 4mg의 엽록소에 해당하는 아나베나를 충진한 trickling-medium 반응기에서 6일동안 1.6ml의수소가 생성되었다

Physiological and morphological characteristics of Anabaena azollae cells immobilized in a synthetic polymer, polyvinyl(PV), were investigated. The cell density of the non-immersed PV foam reached 4.4mg Chl/g dry wt. PV foam. This is 8 times higher than that of PV-immobiliz action in immersed batch system. And MSX-induced ammonia productivity and the photosynthectic oxygen evolution activity are higher than that of free cells after short-term dark storage. Nitrogenase activity and thermostability of photosynthetic activity are also higher than that of free Anabaena cells after immobilization. Total hydrogen production reached to 1.6ml H2 per reactor (total 4mg Chl) after 6 days.

The effect of wtlitc light on unaeraten growth of Baker's yeast and the accompanying ethanol production has been studied in a batch process at 27℃. Over the 80-hour period of the Champagne yeast process without pH control, the cull growth was inhibited by the fluorescent light. Another observed difference between the runs is that the drop and subsequent rise in redox potential occurred much sooner in the fermentation with light than in the fermentation without light. This preliminary study indicated that ethanol production could be enhanced by light as the cell concentration is repressed. The possible pathway, shift of the sugar substrate toward ethanol and away from cells was manifested by another difference as well. As observed under the microscope, many of the yeast cells grown under light budded without dividing by the normal fission process as they did in the dark. Furthermore, the undivided and branched (light grown) cell did not agglutinate at the end of the fermentation process as did the distinct spherical (dark grown) cells.

The effects or polyamines on growth, anthocyanin contents and B-glucan synthetase(GSII) activity in carrot hairy root were studied. Growth of hairy root was stimulated somewhat when each polyamine concentration was treated, especially addition of 1mM spermidine resulted in about 20% increase. On the whole, the axial diameter of hairy root was increased in response to increase in concentration of polyamine. On the other hand, GSII activity was stimulated in response to increase in concentration of polyamine, especially addition of 1mM spermine resulted in about 100% increase of activity. Therefore increased activity of GSII stimulated growth and thickness of hairy root. Anthocyanin contents were not affected by the polyammine.

난과식물의 형질전환 유도의 기초연구로서 자란(Bletilla striata)의 미성숙 종자로 부터 embryogenic callus를 유도하고, 이 배발생 캘러스의 현탁배양을 하여 이로부터 분리한 원형질체에 여러가지 조건하에서 electroporation을 행하고 원형질체의 생존율(viability)을 조사하였다. Voltage와 capacitancy의 증가에 의해 생존율은 감소를 가져 왔으며, HBM buffer에서 4℃로 electroporation시 원형질체의 생존율에 있어서 안정성을 높일 수 있었다.

We have investigated influencing factors on viability of Bletilla striata protoplasts electroporated in the presence of various electrical conditions. Cultures of embryogenic callus and embryogenic cell suspension were established with immature seeds of Bletilla striata. Viabilty of electroporated protoplasts was decreased according to the increaseing of electroporation voltage and capacitance. An optimal condition of electroporation for viable protoplasts was in HBM buffer at 4℃.

In this study poly (1-methyl-4-vinylpyridinium iodide-co-styrene) membrane with pyridinium cation as a fixed carrier was synthesized and the transport characteristics of the membrane was examined over various factors. As the concentration of the fixed carrier in the membrane was increased, the water content was increased. Meanwhile, the counter current of the organic anion and the chloride ion, the following results were obtained. Initial flux of Cl-, organic anion and Na+ decreased with the increasing thickness of membrane, and as the concentration of the fixed carrier increases, the initial flux of Cl- and organic anion increase but the initial flux of Na+ decreased. The flux equation of the organic anion, CCl3COO- was obtained from saturation kinetics as follows; V0={{{{ { (8.67 TIMES { 10}^{-5 }) CDOT LEFT [Nacl] } over {9.63 TIMES { 10}^{-2 }+ [Nacl] } mol/cm2h}}}}

한외여과막을 이용하여 알부민 용액을 회분식 혼합분리기에서 분리하는 현상들을 연구하였다. 본 연구는 작업시간과 작업압력에 따라 변하는 투과플럭스에 대한 것이다. 또한 실험은 pH 4.8에서 수행되었다. 알부민의 정량은 광학적으로 측정하였으며, Lowry법을 사용하였다. 본 연구 결과는 희박 알부민 용액의 한외여과는 작업시간에 따라 투과량 플럭스가 완만하게 감소되며, 제한된 사용압력에서 알부민 용액의 농도분극 현상은 자석교반에 의해 제기 되었다.

The experimental investigations about ultrafiltration(UF) of bovine serum albumin(BSA) solutions were conducted with a batch stirred cell. This study was investigated on the permeate flux. The experiment was carried out at pH 4.8. Protein concentrations were measured spectrophotometrically. For very dilute samples, a Lowry method was used. In the ultrafiltration of dilute BSA solutions, the permeate flux according to working time was decreased smoothly and at isoelectric point, concentration polarization of BSA solution was ignored at limited working pressures by magnetic stirring.