• 한국미생물·생명공학회지
• /
• 제9권3호
• /
• pp.159-164
• /
• 1981

부분적 항상성변이주인 Bacillus megaterium (KFCC 10029)가 생산하는 페니실린 아미다제를 예로하여 강화된 $Ca^{++}$-alginate gel에 의한 포괄방법을 이용하는 효소 고정화 방법을 제시하였다. 발효액으로 부터 celite 흡착법에 의해 효소를 분리한 후 alginate의 gellatin용액에 혼합하고 $Ca^{++}$ 용액에서 응고시키고 glutaraldehyde로 처리하여 성형하였다. 이렇게 하여 얻은 고정화효소의 최적 pH 및 온도는 각각 8.0과 6$0^{\circ}C$였다. Km value 와 6-APA 및 페닐초산에 의한 저해 상수는 각각 2.6mM, 7.4mM, 21.2mM이었다. Gel의 증가된 물리적 강도 때문에 반응조 조작중 흡착효소의 유실을 성공적으로 없앨수 있었다. 관형식 반응조에서의 고정화 효소의 반감기는 4$0^{\circ}C$와 3$0^{\circ}C$에서 각각 6일 및 30일이었으며, 이것은 흡착효소와 비교해 볼 때 6-8배의 증가치이다. 결론적으로 alginate gel 포괄방법에 의한 효소고정화 방법에 있어, 본 연구에서 개발된 개량된 방법을 사용함으로써 고정화효소의 물리적 강도 및 안정도를 크게 증가시킬 수 있었다.

• 한국식품과학회지
• /
• 제30권5호
• /
• pp.1163-1168
• /
• 1998

유기용매에 의한 잔류농약 추출방법을 대체할 신속, 간편, 값싼 방법의 개발을 목표로, 어류조직에 5종의 유기인계 농약 표준용액을 첨가하여, 추출온도와 압력별, 이산화탄소 유속별, 보조용매 종류별, 어류 시료량별, 어류 종류별로 초임계 이산화탄소를 이용하여 첨가회수율을 측정하였다. 조피볼락에 유기인계 농약 표준용액을 첨가한 후 흡수제로 celite를 혼합하여 초임계 이산화탄소로 추출하였을 때 첨가회수율은 추출온도와 추출압력이 낮을수록 증가하였고, 이산화탄소 유속이 높을수록 감소하였다. 보조용매 사용에 따른 회수율의 증가효과는 크지 않았으며, 사용한 보조용매로 methanol, acetone, methylene chloride 중 methylene chloride 10%와 더불어 추출하였을 때 첨가회수율이 가장 높았다. 어류 시료량이 적을수록 첨가회수율이 증가하였다. 조피볼락, 방어, 옥돔, 정어리, 고등어에서의 첨가회수율은 각각 $66.7{\sim}86.3%$, $56.2{\sim}79.2%$, $57.6{\sim}77.8%$, $84.2{\sim}96.3%$, $74.6{\sim}83.6%$로 지방함량이 높은 시료는 지방함량이 낮은 시료보다 첨가회수율이 높았다.

• 대한환경공학회지
• /
• 제22권6호
• /
• pp.991-1000
• /
• 2000

메탄올 주요 탄소원으로 사용하며 가용성 메탄산화효소 (soluble methane monooxygenase, sMMO)를 분비하는 혼합 메탄차화균을 celite R-635에 고정화시켜 TCE를 함유한 폐수를 연속적으로 처리하였다. 2 ppm의 TCE를 공급했을 때 각각 6. 20시간의 체류시간에서 약 80.4, 84.5%의 처리 효율을 얻었으며, 체류시간이 증가함에 따라서 제거율도 서서히 증가하였다. 5 ppm의 TCE를 공급하고 10시간 동안 체류시켰을 때, '초기에는 TCE의 제거능이 낮았으나 점차 81%까지 증가하였다. 또한 산소를 공급하면서 메탄을 주기적으로 공급할 때 5 ppm의 TCE가 체류시간 10. 15시간에서 각각 88.5, 96.5%까지 제거되었다. 반응기 내에 산소가 고갈된 상태에서 메탈을 고농도로 공급하면 MMO에 흡착된 메탄의 산화반응이 쉽게 진행되지 않아 TCE 분해능이 떨어졌다. 파일롯트 플랜트 규모의 생물막 반응기에서의 TCE 분해 실험 결과, 실제 크기 규모의 공장에도 충분히 적용 가능할 것으로 사료되었다.

• Journal of Microbiology and Biotechnology
• /
• 제20권7호
• /
• pp.1086-1091
• /
• 2010

This study explored the use of gellan gum as an immobilization matrix for the production of cyclosporin A (CyA) by immobilized spores and mycelia of Tolypocladium inflatum MTCC 557. Different carriers, such as gellan gum, sodium alginate, celite beads, and silica, were tested as immobilization carriers, along with the role of the carrier concentration, biomass weight, number of spore-inoculated beads, and repeated utilization of the immobilized fungus. The maximum CyA production was 274 mg/l when using gellan gum [1% (w/v)], and a mycelial weight of 7.5% (w/v) supported the maximum production of CyA. Additionally, the addition of a combination of $_L$-valine (6 g/l) and $_L$-leucine (5 g/l) after 48 h of fermentation produced 1,338 mg/l of CyA when using gellan gum. The immobilized mycelia beads were found to remain stable for four repetitive cycles, indicating their potential for semicontinuous CyA production.

• Journal of Ginseng Research
• /
• 제24권1호
• /
• pp.41-45
• /
• 2000

인삼전분으로부터 기능성 말토올리고당을 생산하기 위하여 인삼전분에 대한 말토 올리고당 생산 최적조건을 검토하고 이들을 정제 한 후 물리화학적 특성과 장내 유용 세균에 대한 생육효과를 조사하였다. Amano-A amylase를 사용하였을 때 glucose가 4개 이상 결합된 말토 올리고당이 많이 생성되어 최적 효소로 선정하였고, 이 효소를 이용한 말토 올리고당 생산 최적조건은 인삼전분 10%, 효소 첨가 농도 50 unit/g 전분 과 반응시간 24시간이었다. 인삼전분을 효소분해하여 생산하고 carbon-celite로 정제한 말토올리고당의 점도와 보수력은 각각 37.7 cps(20。C)와 110%(75%상대습도)로 설탕에 비하여 높았으며, 감미도는 설탕의 25.6% 이었다. 또한 생산된 말토올리고당은 장내 유용세균인 Biflidobacterium infantis의 생육을 촉진시켰다

• Biotechnology and Bioprocess Engineering:BBE
• /
• 제6권5호
• /
• pp.337-340
• /
• 2001

A galactooligosaccharide(GalOS)-producing yeast, OE-20 was selected from forty seven strains of yeast growing in Korean traditional Meju (cooked soybean) and the yeast was tentatively identified as Kluyveromyces maxianus var lactis by its morphology and fermentation profile. A maximum yield of 25.1%(w/w) GalOS, which corresponds to 25.1 g of GalOS per liter, was obtained from the reaction of 100 g per liter of lactose solution at 3$0^{\circ}C$, pH 7.0 for 18 h with an intracellular crude $\beta$-galactosidase. Glucose and galactosidase were found to inhibit GalOS formation. The GalOS that were purified by active carbon and celite 545 column chromatography were supplemented in MRS media and a stimulated growth was observed of some intestinal bacteria. In particular the growth rate of Bifidobacterium infantis in the GalOS containing MRS broth increased up to 12.5% compared to that of the MRS-glucose broth during a 48h incubation period.

• 한국환경성돌연변이발암원학회지
• /
• 제15권2호
• /
• pp.106-114
• /
• 1995

A method was developed to detect total mutagenicity of fried fish for S. typhimurium TA98, using Ames assay. Method described herein circumvented problems associated with the sample preparation for Ames assay, i.e., a multi-purification step of sample and interference with solvent residuals. Experiment A, the best method developed in the present study, consisted of two important steps: pH adjustment of the aqueous sample solution from fried fish samples to remove impurities, and simultaneous distillation extraction (SDE) for partially purified samples to remove volatile compounds from solvents. The procedure and results were described as below. Fillet of gizzard shad (Konosirus punctatus) fish sample fried for 10 min each side on the temperature-controlled fry-pan (210$\circ$C) was homogenized in an aqueous acidic solution (pH 2) with a homogenizer, followed by filtration through Celite. The tiltrate (pH 2), removed some impurities by extraction with chloroform:methanol (2:1, v/v) mixture, was adjusted pH to 10 and then centrifuged to remove precipitate. The ethylacetate extract from the tiltrate of pH 10 was rotoevaporated and purified by SDE apparatus for 2 hours. Experiment A revealed significantly higher revertants (1928 per 25 g fried sample) than other Experiment (B, C, or D) tested. Experiment A gave good results in the mutagenicity test of fried fish sample with few purification steps using only 25 g fried sample and 650 ml of solvents; and thus this method could be a useful tool for the screening the mutagenicity or antimutagenicity of other foods as well.

• 한국미생물·생명공학회지
• /
• 제22권6호
• /
• pp.646-650
• /
• 1994

Aspergillus terreus NRRL 1960 was immobilized on various alginate gel beads, Celites, and polyurethane foam cubes, and the comparisons were made for the production of itaconic acid according to the types and sizes of each carrier. The levels of itaconic acid produced from Ca- alginate and Sr-alginate were similar, and the addition of bentonite to Ca- and Sr-alginate resulted in an increase of itaconic acid. The addition of 1.67% bentonite and 0.33% starch to Sr-alginate (SABS bead) produced higher level of itaconic acid (11.59 g/1) than other gel beads. A decrease in the size of Celite increased the itaconic acid production, and the smallest size of Celites, R- 634, produced 6.37 g/l of itaconic acid. Among various types of polyurethane foam cubes, HR 08 (2X2X2 cm) produced about 19 g/l of itaconic acid, which was more efficient than other carriers. In a repeated batch culture using immobilized cells on polyurethane foam cubes (HR 08, 2X2X2 cm), the stability of itaconic acid production was maintained up to 4 batches. Also, the possibility of itaconic acid production by continuous culture was shown in a packed-bed reactor.

• 대한수의학회지
• /
• 제13권1호
• /
• pp.23-30
• /
• 1973

Thin layer, paper and column chromatography were compared for the separation, detection and quantitation of three kinds of estrogen in urine of dairy cows. While thin layer chromatography utilizing silica gel was better for the detection of estrogens, column chromatography using celite 545 was preferable. Spectrophotometry was compared with fluorometry for determination of estrone, estradiol-17 ${\beta}$ and estriol eluted by paper chromatography and column chromatography. Optical density of three standard estrogens showed almost same curve at maximum absorption wave length of 230 and $282m{\mu}$. However, the former showed a higher peak. In fluorometry, the fluorescence intensity of estrone and estradiol-17 ${\beta}$ were rather strong, when the estrogens were dissolved in sulfuric acid, and showed higher sensitivity than that of the spectrophotometry. However, in the case of estriol was exceptional.

• Journal of Microbiology and Biotechnology
• /
• 제12권4호
• /
• pp.557-562
• /
• 2002

Physiological characteristics such as specific productivity, morphology of Streptomyces cells Immobilized on celite beads, and operational stability at different dilution rates were investigated in continuous immobilized-cell cultures for the production of kasugamycin. At a dilution rate (D) of 0.05 $h^{-1}$, a relatively high specific productivity was attained and the loss of cell-loaded beads was negligible. At D=0.1 $h^{-1}$, a higher specific productivity and cell concentration could be obtained, resulting in a significantly improved volumetric kasugamycin productivity. However, no stable operation could be maintained due to a significant loss of cell-loaded beads from the reactor that was caused by their fluffy morphology developed in the later stage. At D=0.2 $h^{-1}$, the production of kasugamycin and cell growth were observed to be severely inhibited by the high concentration of residual maltose.