Reduction of Bacillus cereus Contamination in Biofilms on Stainless Steel Surfaces by Application of Sanitizers and Commercial Detergent

Lee, Min-Jeong,Ha, Ji-Hyoung,Kim, Yong-Su,Ryu, Jee-Hoon,Ha, Sang-Do The Korean Society for Applied Biological Chemistr 2010 Applied Biological Chemistry (Appl Biol Chem) Vol.53 No.1

We established the effectiveness of a washing, detergent and sanitizer treatments for reducing Bacillus cereus (B. cereus) contamination in biofilms on stainless steel surfaces. A water treatment did not affect biofilms and chlorine treatments at 200 ppm for 10 min and 300 ppm for 5 min, iodophor at 200 ppm for 10 min, and QAC at 400 ppm for 10 min were used to eliminate all B. cereus cells. B. cereus cells after detergent treatment were eliminated by chlorine at 100 ppm for 10 min, 200 ppm for 5 min, and 300 ppm for 3 min, and with iodophor at 100 ppm for 10 min and 200 ppm for 10 min, and QAC at 400 ppm for 10 min.

Dose-linear pharmacokinetics of oleanolic acid after intravenous and oral administration in rats

Jeong, Dong Won,Kim, Young Hoon,Kim, Hui Hyun,Ji, Hye Young,Yoo, Sun Dong,Choi, Won Rack,Lee, Soo Min,Han, Chang-Kyun,Lee, Hye Suk WILEY PUBLISHERS 2007 BIOPHARMACEUTICS AND DRUG DISPOSITION Vol.28 No.2

<P>The pharmacokinetics of oleanolic acid was evaluated in vitro and in vivo. From Caco-2 cell permeation studies, oleanolic acid was a low permeability compound with no directional effects, suggesting a low in vivo absorption mediated by a passive diffusion. Oleanolic acid was metabolically unstable following incubation with rat liver microsomes in the presence of NADPH. After intravenous injection at doses of 0.5, 1 and 2 mg/kg doses, oleanolic acid showed dose-linear pharmacokinetics as evidenced by unaltered CL (28.6–33.0 ml/min/kg), V<SUB>ss</SUB> (437–583 ml/kg), dose-normalized AUC (16.0–17.9 µg min/ml based on 1 mg/kg) and t<SUB>1/2</SUB> (41.9–52.7 min). Following oral administration of oleanolic acid at doses of 10, 25 and 50 mg/kg, T<SUB>max</SUB>, t<SUB>1/2</SUB>, dose-normalized C<SUB>max</SUB> (66–74 ng/ml based on 25 mg/kg) and dose-normalized AUC (5.4–5.9 µg min/ml based on 25 mg/kg) were comparable between 25 and 50 mg/kg dose, but the plasma concentrations at 10 mg/kg dose were not measurable as they were below the limit of quantitation (2 ng/ml). The absolute oral bioavailability was 0.7% for oral doses of 25 and 50 mg/kg. The extent of urinary excretion was minimal for both i.v. and oral doses. The very low oral bioavailability of oleanolic acid could be due to a poor absorption and extensive metabolic clearance. Copyright © 2007 John Wiley & Sons, Ltd.</P>

Production and Characterization of Enzymes Involved in Chitin Catabolic Cascade from a Bacterial Strain Isolated from Soil

( Ji Hyun Lee ),( Jeong In Lee ),( So Yeon Park ),( Yoo Kyeong Jang ),( You Bin Lim ),( Hye Yoon Lee ),( Young Min Jung ),( Hae Chang Lee ),( Jong Hwa Lee ),( Shaheen Amna ),( Jae Kweon Park ) 한국키틴키토산학회 2019 한국키틴키토산학회지 Vol.24 No.1

The present study was aimed to isolate the bacteria producing chitinolytic enzymes including chitin deacetylase (CDA) from soil origin. About 24 bacteria were screened for their chitinolytic enzymes producing ability on the basis of colloidal chitin. Amongst one of the most potent isolates designated to JI-02 was further selected as the most prominent chitinolytic and CDAlike enzyme (CDA-X) producer based on the ability of deacetylation of an artificial substrate pNP-acetamilide. The maximum production of CDA-X in crude enzyme from JI-02 was observed in the presence of 1% colloidal chitin at 37°C and pH 6.4 after 120 h of incubation. Potent enzyme activity of CDA-X was determined toward pNP-acetamilide, demonstrating that optimal pH, temperature and ionic strength of the CDA-X were assessed to be 7.0, 52°C and 125 mM, respectively. Unexpectedly, Nacetylglucosamine (GlcNAc) was not fully converted by the action of CDA-X to glucosamine (GlcN) under the established conditions. Further study on enzyme activity toward chitin-oligosaccharides consisting of multi-N-acetylglucosamine (GlcNAc)n, n=2-5 may be necessary to elucidate the mode of action which requires the minimum size of (GlcNAc)n. However, our data suggest that CDA-X can convert chitin to chitosan with the maximum yield of approximately 0.08g/L during the fermentation of the strain in the presence of chitin. Furthermore, we found that crude enzyme showed the significant chitosanolytic activity. Taken together, our data suggest that the strain JI-02 may be a potential candidate as a particular strain for better understating of chitin catabolic pathway.

원산지별 감초추출물의 항산화활성 증가를 위한 효율적인 추출조건 탐색

하지훈 ( Ji Hoon Ha ),이혜미 ( Hye Mi Lee ),권순식 ( Soon Sik Kwon ),김해수 ( Hae Soo Kim ),김문진 ( Moon Jin Kim ),전소하 ( So Ha Jeon ),정유민 ( Yoo Min Jeong ),황준필 ( Jun Pil Hwang ),박종호 ( Jong-ho Park ),최영기 ( Yung-key 대한화장품학회 2013 대한화장품학회지 Vol.39 No.4

본 연구에서는 한국 및 중국산 감초(Glycyrrhiza uralensis), 그리고 우즈베키스탄산 감초(Glycyrrhiza glabra)를 대상으로 추출용매, 추출온도, 추출시간 등 추출조건별 추출물을 제조하고 이들 추출물들의 추출 수율과 항산화 활성을 비교하여 최적의 추출조건을 선정하였다. 항산화 활성 중 자유 라디칼(1,1-phenyl-2-pic-rylhydrazyl, DPPH) 소거활성은 85% 에탄올로 60 ℃에서 6 h 동안 추출한 조건에서 한국 감초로부터 얻은 추출물이 가장 높은 활성(46.05%)을 나타내었다. 루미놀 발광법을 이용한 추출물들의 총 항산화능 측정 실험과 피부 광노화에 중요한 ¹O₂으로 유도된 세포막 손상에 대한 추출물들의 세포 보호 효과를 측정한 실험 모두에서도 위의 조건에서 가장 높은 항산화 활성을 나타내었다. 특히, 한국 감초는 τ₅₀이 116.4 min으로 비교 물질인(+)-α-tocopherol (28.5 min)보다 약 4 배나 높은 세포 보호 효과를 나타내었으며, 추출 수율은 18.75%로 우즈베키스탄 및 중국 감초보다 각각 1.2 배 및 2.5 배의 추출 수율을 나타내었다. 따라서, 본 연구 결과는 항산화 소재로 화장품에 응용하기 위하여 감초로부터 추출물을 얻기 위한 최적의 조건은 85% 에탄올로 60 ℃에서 6시간 동안 추출하는 것임을 보여주었다. In this work, licorice extracts were prepared using various extraction conditions such as extraction solvent, temperature, and time from Glycyrrhiza uralensis (G. uralensis) produced in Korea and China and Glycyrrhiza glabra (G. glabra) in Uzbekistan. The optimum extraction condition was selected from the extraction yields and antioxidative activities of extracts. Korea licorice extracts showed the highest free radical (1,1-diphenyl-2-picrylhydrazyl, DPPH) scav-enging activity (46.05%) under the extraction condition of 85% ethanol at 60 ℃ for 6 hours. The prominent ROS (reactive oxygen species) scavenging activity using luminol-dependent chemiluminescence assay and the cellular protective effect against ¹O₂ induced cellular membrane damage were also shown from the extracts obtained from the same condition. Especially, Korea G. uralensis extracts exhibited the higher prominent protective effect (τ₅₀ = 116.4 min) than (+)-α-tocopherol (τ₅₀ = 28.5 min) and the extraction yield of Korea licorice extract was 18.75%, which is 1.2 times and 2.5 times higher than that of Uzbekistan and China, respectively. These results indicate that the extraction condition of 85% ethanol at 60 ℃ for 6 hours is optimal to prepare licorice extracts, which can be applicable as antioxidative cosmetic materials.

연구 논문 : 슬러지 냉동처리에 의한 갈조로부터 바이오가스 생산

김지윤 ( Ji Youn Kim ),정행순 ( Haeng Soon Jeong ),우대식 ( Dae Sik Woo ),김상민 ( Sang Min Kim ),김인수 ( In Soo Kim ),이재화 ( Jae Hwa Lee ) 한국공업화학회 2012 공업화학 Vol.23 No.6

본 연구에서는 해조류 다시마를 바이오매스로 이용하는 혐기성 소화로부터 바이오가스를 생산하였다. 최적의 혐기성 배양조건을 확립하기 위해 슬러지는 -70 ℃에서 20 min 동안 냉동 전처리를 하였다. 대조군과 비교했을 때 수소와 메탄가스는 각각 2.7배와 3.4배 증가한 667.28 mL/L와 3420.24 mL/L를 생산하였다. 냉동 전처리한 슬러지의 초기 pH 최적 조건은 7.0이었고, 다시마 바이오매스의 초기 pH 최적 조건은 8.0이었으며 알칼리 조건에서 보다 산성 조건에서 바이오가스 생산량이 크게 감소하는 것을 확인할 수 있었다. 슬러지의 냉동 전처리와 바이오매스 및 슬러지의 최적 pH 조건에서 최대 643.73 mL/L의 수소와 4291.6 mL/L의 메탄가스를 생산하였다. 이는 대조군과 비교했을 때 각각 2.6배와 4.3배 증가한 생산량이었다. 또한 최적 조건의 5-L 회분식 혐기성 배양에서 바이오가스의 생산량을 측정한 결과 기질에 포함된 다시마에 의해 생산될 수 있는 최대 생산량은 수소 1605.03 mL/L와 메탄가스 4593.71 mL/L로 확인되었다. In the present study, biogas was produced from the anaerobic digestion of marine macroalgae (Laminaria japonica) biomass. The optimal anaerobic condition for producing the sludge was the freeze treatment at -70 ℃ for 20 min. Total amounts of hydrogen and methane gas produced were 667.28 mL/L and 3420.24 mL/L, respectively, which were 2.7 and 3.4 times greater than that in the control group. Freeze treatment of sludge produced the maximum biogas under an initial optimum pH of 7.0 and the maximum biomass at an initial optimum pH of 8.0. We confirmed that biogas production was greatly reduced under acidic conditions compared to that under alkaline conditions. Sludge was freeze treated, and the biomass and sludge production was optimal the total amounts of hydrogen and methane gas produced were 643.73 mL/L and 4291.6 mL/L, respectively, which were 2.6 and 4.3 times greater than in the control group. Also the results showed that under optimal conditions in a 5-L bioreactor, a maximum of 1605.03 mL/L of hydrogen and 4593.71 mL/L of methane gas could be produced by the substrate contained in the marine macroalgae biomass.

Exploiting Microwave Chemistry for Activation of Metal-Organic Frameworks

Lee, Eun Ji,Bae, Jinhee,Choi, Kyung Min,Jeong, Nak Cheon American Chemical Society 2019 ACS APPLIED MATERIALS & INTERFACES Vol.11 No.38

<P>Microwave is thought of as a useful electromagnetic radiation tool because it is often used in real life as well as in a variety of chemical processes. Meanwhile, activation of metal-organic frameworks (MOFs), which must be essentially done to remove coordinating and pore-filling solvents before the use of MOFs for various applications, has been performed commonly with the methods of heat supply or solvent exchange. Here, we show a new methodological microwave activation (MA), realizing it with various MOFs such as HKUST-1, UiO-66, and MOF-74s. For instance, microwave irradiation to the MOF samples for 4-35 min leads to the complete activation of the MOFs without structural damage. As described below, we further demonstrate that the solvent-assisted MA, which is the MA process performed after the solvent exchange, can substantially reduce the time for the activation by 4 min.</P> [FIG OMISSION]</BR>

Biodistribution and PET imaging of [¹⁸F]FMISO in mousecolon cancer xenografted mice

Seelam, Sudhakara Reddy,Lee, Ji Youn,Kim, Young Joo,Lee, Yun-Sang,Jeong, Jae Min Korean Society of Radiopharmaceuticals and Molecul 2015 Journal of radiopharmaceuticals and molecular prob Vol.1 No.2

Hypoxia is an important adverse prognostic factor for tumor progression and is a major cause of failure of radiation therapy. In case of short-term hypoxia, the metabolism can recover to normal, but if hypoxia persists, it causes irreversible cell damage and finally leads to death. So a hypoxia marker would be very useful in oncology. In particular, 2-nitroimidazole can be reduced to form a reactive chemical species, which can bind irreversibly to cell components in the absence of sufficient oxygen, thus, the development of radiolabeled nitroimidazole derivatives for the imaging of hypoxia remains an active field of research to improve cancer therapy result. 2-nitroimidazole based hypoxia marker, [$^{18}F$]FMISO holds promise for the evaluation of tumor hypoxia by Positron emission tomography (PET), at both global and local levels. In the present study, [$^{18}F$]FMISO was synthesized using an automatic synthesis module with high radiochemical purity (>99%) in 60 min. Immunohistochemical analysis using pimonidazole confirmed the presence of hypoxia in xenografted CT-26 tumor tissue. A biodistribution study in CT-26 xenografted mice showed that the increased tumor-to-muscle ratio and tumor-to-blood ratios from 10 to 120 min post-injection. In the PET study, [$^{18}F$]FMISO also showed increased tumor-to-muscle ratios from 10 to 120 min post-injection. In conclusion, this study demonstrates the feasibility and utility of [$^{18}F$]FMISO for imaging hypoxiain mouse colon cancer model using small animal PET.

Improving the subcritical water extraction of flavonoids narirutin and hesperidin from Citrus unshiu peel by pulsed electric fields

Hui-Ju Kim,Mi-Ri Kwon,Hye-Ji Kang,Na-Yeon Kim,Hee-Jeong Hwang,Min-Jung Ko,Myong-Soo Chung 한국산업식품공학회 2017 학술대회 및 심포지엄 Vol.2017 No.11

Citrus fruit is important source of flavonoids, mainly flavanones which are narirutin and hesperidin. Those citrus flavonoids have been found to have health-related properties including antioxidant, anticancer, and anti-inflammatory. The main purpose of this study was to verify that the extraction of narirutin and hesperidin from Citrus peel can be more effective by combining pulsed electric field (PEF) pre-treatment and subcritical water extraction (SWE). Citrus unshiu peels were treated with PEF under conditions of electric field strength (3 kV/cm) and times (1 and 2 min). Subsequent SWE was conducted by using a Dionex Accelerated Solvent Extractor (ASE, Model 350) at extraction temperature 170°C for 10 min. The total flavonoids content was measured by using the aluminum chloride colorimetric method and the antioxidant capacity was analyzed by the Ferric reducing antioxidant power (FRAP) assay using spectrophotometer. The concentrations of narirutin and hesperidin were increased as PEF pre-treatment time increased. The highest concentrations of narirutin and hesperidin were 13.41 mg narirutin/g dry citrus peel and 141.16 mg hesperidin/g dry citrus peel at PEF pre-treatment condition of 3 kV/cm and 2 min. The total flavonoids contents of the extracts increased 105.2% and 123.1% for citrus peel PEF treated at 1 and 2 min, respectively. In addition, compared to the untreated sample, PEF pre-treatments of 1 and 2 min increased the antioxidant capacity of the extracts 109.2% and 160.8%, respectively. Therefore, the results demonstrate the potential of PEF pre-treatment to improve the SWE of flavonoids from citrus unshiu peel.

Impact of Irradiation Time on the Hydrolysis of Waste Activated Sludge by the Dielectric Heating of Microwave

Tae Joo Park,Im Gyu Byun,Jae Ho Lee,Ji Sung Lim,Jeong Min Lee 대한환경공학회 2014 Environmental Engineering Research Vol.19 No.1

The effects of initial solid concentration and microwave irradiation (MWI) time on the hydrolysis of waste activated sludge (WAS)were investigated. MWI time strongly influenced WAS hydrolysis for all initial solid concentrations of 8.20, 31.51, and 52.88 g VSS/L. For all WAS, the volatile suspended solids (VSS) solubilization degree ranged from 35.6% to 38.4% during a total MWI time of 10 min. Solublechemical oxygen demand (SCOD) concentration increased at a rate proportional to the decrease of VSS during the MWI. However, the clearly different VSS solubilization patterns that were observed during the MWI were explained by the 2-step hydrolysis of WAS, consisting of the initial disintegration of the easily degradable part of the sludge, followed by the subsequent disintegration of the hardlydegradable part of the sludge. WAS hydrolysis rates for 3 to 6 min of MWI were significantly lower than those for less than 3 min, or more than 6 min. From these results, 3 min MWI time and WAS of 31.51 g VSS/L (centrifugal thickener WAS) showed the most efficienthydrolysis of WAS at 36.0%. The profiles of total nitrogen (T-N) concentrations corresponded well to the SCOD increases in terms of the empirical formula of bacterial cell mass (C5H7O₂N). The negligible T-N increase and pH decrease during WAS hydrolysis by MWI will allowthe application of this process to subsequent biological processes, such as anaerobic digestion.

이동형 스크러버를 이용한 암모니아 및 톨루엔의 제거 효율

김재영 ( Jae-young Kim ),김장윤 ( Jang-yoon Kim ),이연희 ( Yeon Hee Lee ),김민선 ( Min Sun Kim ),김민수 ( Min-su Kim ),김현지 ( Hyun Ji Kim ),류태인 ( Tae In Ryu ),정재형 ( Jae Hyeong Jeong ),황승율 ( Seung-ryul Hwang ),김균 ( Ky 한국환경농학회 2018 한국환경농학회지 Vol.37 No.1

BACKGROUND: The mobile vortex wet scrubber was developed to remove the harmful chemicals from accidental releases. However, there was a disadvantage that it was limitedly used for volatile organic compounds (VOCs) such as toluene according to the physicochemical properties. This study compared the removal efficiencies of an improved mobile scrubber on toluene and ammonia by applying diverse adsorption and absorption methods. METHODS AND RESULTS: The removal efficiencies on harmful chemicals were examined using various adsorption and absorption methods of water vortex process (C), phosphoric acid-impregnated activated carbon adsorption (PCA), pH-controlled water (pH 2.5) vortex process absorption with sulfuric acid (SWA) after ammonia exposure, granular activated carbon adsorption (GCA), and activated carbon mat adsorption (CMA) after toluene exposure. As a result, the best removal efficiency was shown in the SWA for ammonia and GCA for toluene. Also, the SWA and GCA methods were compared with different concentration levels. In the case of ammonia exposure (5, 10 and 25%), there was no difference by concentration levels, and the concentration in the outlet gradually increased, with pH change from acid to base. In the case of toluene exposure (50, 75 and 100%), the outlet concentration was higher relative to the exposure concentration in the initial 10 min, but the outlet concentration was remained steady after 10 min. CONCLUSION: The newly improved mobile scrubber was also effective in removing VOCs through adsorption techniques (activated carbon, activated carbon fiber, carbon mat filter etc.), as well as removing acid-base harmful chemicals by neutralization reaction.