Aureobasidium pullulans IMS-822가 생산하는 ${\beta}-(1{\to}3)(1{\to}6)-Glucan$의 특성 분석

이석준,안극현,박찬선,윤병대,김민수,Lee, Seog-June,Ahn, Keug-Hyun,Park, Chan-Sun,Yoon, Byung-Dae,Kim, Min-Soo 한국미생물학회 2009 미생물학회지 Vol.45 No.1

국내 토양시료로부터 점액성 고분자물질을 생산하는 효모 균주를 분리 및 동정하여 Aureobasidium pullulans IMS-822라 명명하였다. A. pullulans IMS-822가 생산하는 외분비성 폴리머를 정제 및 동결 건조하여 구조분석을 수행하였다. HPLC를 이용한 구성당 성분분석에서 포도당 단일성분으로 구성되어 있음을 확인하였다. FT-IR을 이용한 구조분석에서는 890 $cm^{-1}$ 부근에서의 ${\beta}-configuration$을 확인하였으며, 3300 $cm^{-1}$ 부근으로 shift 된 완만한 -OH stretching은 폴리머를 구성하고 있는 분자 사이에 강한 수소결합이 작용하고 있는 것으로 추측되었다. $^{13}C-NMR$ 분석결과는 A. pullulans IMS-822가 생산하는 외분비형 다당류인 (1,3)-linked ${\beta}-D-glucosyl$ unit의 6개의 탄소, ${\delta}$ 105.05 ppm (C1), 75.82 ppm (C2), 86.62 ppm (C3), 70.61 ppm (C4), 78.13 ppm (C5), 63.22 ppm (C6) 및 ${\beta}-(1,3)D-glucosyl$ 잔기에 분기사슬 되어 있는 ${\delta}$ 72.11 ppm의 C-6의 signal을 확인할 수 있었다. A. pullulans IMS-822가 생산하는 ${\beta}-(1{\to}3)(1{\to}6)-glucan$의 알칼리 수용액(0.5%, w/v)에 24.0 ${\mu}M$의 Congo red 첨가하여 30분간 반응시킨 후 $400{\sim}700$ nm의 범위에서 최대흡수파장의 변화를 조사한 결과 NaOH의 농도가 증가함에 따라 최대흡수파장은 장파장으로 이동하여 498 nm에서 515 nm까지 이동하였다. 최대흡수파장은 0.4 M NaOH 농도에서 점차로 감소하여 506 nm 부근에서 안정화되는 것으로 나타남으로써 순차적 구조를 가지는 것으로 확인되었다. The exo-polysaccharide producing microorganism, Aureobasidium pullulans IMS-822, was isolated and identified from soil. The viscosity-average molecular weight of exo-polysaccharide was calculated as $8.9{\times}10^5$ by Mark-Houwink equation. The sugar component of exo-polysaccharide was determined as glucose by HPLC analysis. The IR spectra indicated that the exo-polysaccharide has an absorption peak at 890 $cm^{-1}$ for the ${\beta}-configuration$ of D-glucan. The $^{13}C$ NMR signal at ${\delta}$ 86.62 ppm arose from the substituted C-3 of glucose. The signal at ${\delta}$ 72.11 ppm was assigned to C-6 of branched ${\beta}-(1{\to}3)-D-glucosyl$ residues. Viscosity and Congo red reaction indicated that {\beta}-(1{\to}3)(1{\to}6)-glucan$ produced by A. pullulans IMS-822 has a highly ordered hydrogen-bond dependent conformation in aqueous solution, which collapses in strong alkaline solution.

세라믹담체를 이용한 페놀계 산업폐수의 생물학적 처리

오희목,구영환,안극현,장감용,고영희,권기석,윤병대 한국산업미생물학회 1995 한국미생물·생명공학회지 Vol.23 No.6

고농도의 phenol과 formaldehyde를 주성분으로 하는 phenol계 산업폐수를 단계적으로 희석하면서, 혼합균주인 GE2와 세라믹담체를 적용하여 80일간에 걸쳐 생물학적으로 처리하였다. 실험구는 제지폐수 슬러지로 30일간 회분식 운전에 의해 적응시킨 대조구, 이것에 GE2를 첨가한 GE2 처리구 그리고 세라믹담체를 적용한 세라믹처리구로 구분하였다. 원폐수의 80배 희석으로 유입수의 COD_Mn이 1,140mg/l 인 경우 각 실험구의 유출수 COD_Mn은 22∼35mg/l로 큰 차이가 없었으나, 20배 희석의 경우 유입수의 COD_Mn이 4,800mg/l일 때, 대조구, GE2 처리구 그리고 세라믹처리구의 유출수 COD_Mn은 179, 128 그리고 94mg/l로서 세라믹처리구의 처리효율이 98.0%로 가장 높았다. 이때 유출수의 phenol 농도는 각기 10.71, 7.93 그리고 5.60mg/l으로 GE2 및 세라믹담체의 적용에 의하여 처리효율이 향상되었다. 한편, 희석배율이 낮아짐에 따라 COD_Mn과 phenol 처리효율에는 큰 변화가 없으나, 유출수의 COD_Mn과 phenol농도가 높아졌다. 따라서, 원폐수를 40배 희석하여 GE2와 세라믹담체를 첨가하여 처리할 경우 유출수의 COD_Mn과 phenol 농도가 32와 1.02mg/l로 수계의 방류수 수질기준에 충분히 적합한 생물학적 처리로 사료된다. A phenolic resin industrial wastewater containing about 41,000 mg/l of phenol and 2,800 mg/l of formaldehyde was biologically treated by a mixed culture GE2 immobilized on ceramic beads. This study was carried out with three experimental groups : Control-only added the sludge of papermill wastewater ; GE2 treatment-added GE2 to Control ; Ceramic treatment-applied ceramic carrier to GE2 treatment. When the original wastewater was diluted 80 times with aerated tap-water, influent COD_Mn was 1,140 mg/l and that of the effluent was in the range of 22∼35 mg/l, which was not much different among the experimental groups. However, at 20-times dilution, influent COD_Mn was 4,800 mg/l and the effluent COD_Mn of control, GE2 treatment and Ceramic treatment was 179, 128 and 94 mg/l, respectively. COD_Mn removal efficiency by Ceramic treatment was the highest, at 98.0%. At this time, the effluent phenol concentration of Control, GE2 treatment and Ceramic treatment was 10.71, 7.93 and 5.60, respectively. As the dilution times decreased, the removal efficiency of COD_Mn and phenol did not change much, but COD_Mn and phenol concentration of the effluent increased. Consequently, it is likely that the phenolic industrial wastewater containing phenol and formaldehyde can be biologically treated using a GE2 and ceramic carrier and that at 40-times dilution, the effluent completely meets the effluent standards for industrial wastewater treatment plant.

Tremella fuciformis TFCUV5 Mycelial Culture-derived Exopolysaccharide Production and Its Anti-aging Effects on Skin Cells

조민호,김별,주정현,허선연,안극현,이혜자,염현숙,장한수,김민수,김철호,오백록 한국생물공학회 2021 Biotechnology and Bioprocess Engineering Vol.26 No.5

Tremella fuciformis TFC6 mycelia was isolated from its fruiting body. T. fuciformis TFCUV5 was obtained from TFC6 mycelia by ultraviolet mutagenesis to improve extracellular-polysaccharide (EPS) yield. In addition, we investigated the physicochemical properties and functionality of EPS for industrial applications and the effect of EPS on enhancement of the moisturizing factor and antiwrinkle effect in skin cells. The EPS yield was improved upon fermentation by the mutant strain through optimization of the medium composition and culture conditions to a maximum of 8.4 g/L; the productivity was 1.9 g/L·day under optimal culture conditions (initial pH 7.0 at 25°C, 300 rpm, 2 vvm). EPS with a molecular weight of 1.79 × 106 (± 0.721%) comprised mannose, xylose, glucuronic acid, fucose, and glucose. EPS extract increased both moisture and the antiwrinkle factor in skin cells. Therefore, EPS from TFCUV5 might have potential to be used in the cosmetics industry.

A Novel Galactoglucomannan Exopolysaccharide Produced by Oil Fermentation with Pseudozyma sp. SY16

Kwang Nyeon Kim,이용재,조대현,안극현,홍종언,박용일,김희식 한국생물공학회 2020 Biotechnology and Bioprocess Engineering Vol.25 No.5

Recently, the production of exopolysaccharide from Pseudozyma sp. SY16, which is mannosylerythritol lipid-producing yeast, has been occasionally observed during industrial fermentations. Moreover, exopolysaccharides derived from microbes are in high demand for the production of biopolymers. Therefore, this study aimed to investigate the production and characteristics of the exopolysaccharide produced by this strain. In batch fermentations with this strain, the maximum production yield of exopolysaccharide (5.8 g/L) was obtained under olive oil supplementation as a carbon source with culture conditions of 30°C, pH 8.0, and 600 rpm. Through a series of liquid chromatography steps, the exopolysaccharide was successfully purified, and its emulsifying activity was demonstrated. In addition, two-dimensional nuclear magnetic resonance analysis revealed that the exopolysaccharide is a galactoglucomannan with a novel and unique structure, consisting of galactose, glucose, and mannose in the ratio of 1:5:3.

Rapid Concentration of Some Bacteriocin-like Compounds Using an Organic Solvent

정동민,Ki Eun Kim,정성엽,박창수,안극현,김동호,강대욱,전효곤,윤병대,고홍범,Hong Jib Kim,최낙식 한국식품과학회 2011 Food Science and Biotechnology Vol.20 No.5

A new solvent extraction method for isolation of bacteriocin-like compounds (BLCs) from bacterial culture broth was developed. Culture supernatant of Pediococcus acidilactici WRL-1 was mixed with 3 volumes of cold acetone and maintained at −20^oC for 2 h. The solvent and precipitate were separated by centrifugation. Most (95.2±2.5%) pediocin activity was found in the liquid phase and it was obtained by evaporation. This method was also an effective means of isolating other BLCs from cultures of Lactobacillus acidophilus, Lactobacillus plantarum, and Bacillus licheniformis DJ-2. Other solvents (methanol,ethanol, and butanol) were also suitable toward this end.

원유 분해균주 Nocardia sp. H17-1의 분리 및 특성

이창호(Chang-Ho Lee),권기석(Gi-Seok Kwon),김희식(Hee-Sik Kim),서현효(Hyun-Hyo Suh),안극현(Keuk-Hyun Ahn),오희목(Hee-Mock Oh),권태종(Tae-Jong Kwon),윤병대(Byung-Dae Yoon) 한국생물공학회 1996 KSBB Journal Vol.11 No.6

반응표면 분석법을 이용한 neohesperidin 생산 수율의 최적화

Hee-Jong Yang(양희종),Seong-Yeop Jeong(정성엽),Nack-Shick Choi(최낙식),Keug-Hyun Ahn(안극현),Chan-Sun Park(박찬선),Byoung-Dae Yoon(윤병대),Yeon-Woo Ryu(유연우),Soon-Cheol Ahn(안순철),Min-Soo Kim(김민수) 한국생명과학회 2010 생명과학회지 Vol.20 No.11

감귤류는 다양한 기능성과 약효로써의 효능이 입증되면서 소비가 증가하고 있으나, 감귤 가공 후 부산물인 감귤박은 폐기물로써 해양에 투기되고 있어 부산물의 처리가 시급한 실정이다. 따라서 폐감귤박을 이용한 고감도 감미료의 생산 원료인 neohesperidin을 추출하여 폐감귤박을 효율적 이용을 도모하였으나 상당히 미비한 추출수율로 효율성이 감소하였다. 이러한 추출 수율의 문제점을 해결하기 위하여 반응표면 분석법을 이용하여 감귤 가공부산물로부터 neohesperidin의 추출 수율 증진 위한 추출조건의 최적화 연구를 수행하였다. 추출 조건 중 초임계 유체 추출의 수율 증진에 영향을 주는 추출 압력(x₁), 추출 시간(x₂), 보조용매의 농도(x₃)를 주요 인자로 선정하였다. 선정한 인자를 반응표면 분석법에 적용하여 추출 수율의 최적조건을 탐색하였으며, 그 결과 추출 압력이 증가하면서 추출의 수율은 크게 향상되었고, 또한 추출 시간이 길어질수록 추출 수율 또한 증가함을 확인하였다. 또한 초임계 이산화탄소에 ethanol을 보조용매로 첨가할 경우 보조용매의 농도가 높을수록 수율은 급격하게 증가하여, 최종적으로 162.22%까지 neohesperidin의 추출 수율을 증진할 수 있었다. Neohesperidin is a natural new nutrition sweetener, widely existing in plants of dry citrus peel, which can be derived from extraction. Since the sweetness is 1,300-1,500 times greater than that of sugar, neohesperidin are widely used in fruit juices, wines, beverages, bakeries and pharmaceutical formulations, and are particularly suitable for consumption by diabetic patients. However, the yield of extraction from citrus peel waste is very low. In this study optimal yield conditions were determined using response surface methodology (RSM) in order to increase the neohesperidin extraction yield. The critical factors for maximum extraction yield were selected extraction pressure (x₁), extraction time (x₂), and concentration of ethanol (x₃). As a result, the extraction yield was improved when the extracting pressure increased. The extraction yield also increased in a time-dependent manner. When adding ethanol as an assistance solvent to the supercritical carbon dioxide, extraction yield was increased as more ethanol concentration was added. Finally, the extraction yield of neohesperidin was improved to about 162.22% compared to ethanol extraction as a conventional method.