• Journal of Plant Biotechnology
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• 제48권4호
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• pp.271-277
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• 2021

The present study aimed to assess and compare the quality characteristics and antioxidant activities of apple juice and blueberry juice at hourly intervals over a period of time based on the presence or absence of vacuum blending (0 and 800 hPa) using a household blender. Measurement of the dissolved oxygen content revealed that the removal rates of dissolved oxygen were approximately 83% and 86% in the apple and blueberry juice samples, respectively, after vacuum blending. Moreover, compared with general blending, there was little change in the antioxidant property and degree of browning over time with vacuum blending. Furthermore, hourly assessments revealed that the decrease in the polyphenol and flavonoid contents in the apple and blueberry juice samples was significantly lesser with vacuum blending for 3, 6, and 12 h than with general blending. Assessment of the change in ferric reducing antioxidant power (FRAP) activity over time revealed that the rate of decrease in FRAP activity over time was lower with vacuum blending than with general blending for both juice samples. ABTS and DPPH radical scavenging assays performed to determine the change in free radical scavenging activity revealed inhibitory activity at 0, 3, 6, and 12 h and confirmed that vacuum blending resulted in long-lasting antioxidant activities in both apple and blueberry juice samples. Taken together, the present results confirmed that vacuum blending is associated with superior quality maintenance and antioxidant properties in comparison with general blending.

• 한국지하수토양환경학회지:지하수토양환경
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• 제26권1호
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• pp.54-64
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• 2021

The chemical warfare agents (CWAs) have been developed for offensive or defensive purposes and used as chemical weapons in war and terrorism. The CWAs are exposed to the natural environment, transported through the water system and then eventually contaminate soil and groundwater. Therefore, effective decontamination technology to remediate CWAs are needed. The CWAs are extremely dangerous and prodution is strictly prohibited, therefore, it is difficult to use CWAs even in experimental purpose. In this study, 2,4-dichlorophenoxyacetic acid (2,4-D) was chosen as a model representative CWA because it is a simulant of anti-plant CWAs and one of the major component of agent orange. The optimum degradation conditions such as oxidant:activator ratio were determined. The effects of hydroxylamine and chelating agents such as citric acid (CA), oxalic acid (OA), malic acid (MA), and EDTA addition to increase Fe2+ activation were also investigated. Scavenger experiments using tert-butyl alcohol (TBA) and ethanol confirmed that although both sulfate (SO4•-) and hydroxyl radical (•OH) existed in Fe2+-persulfate system, sulfate radical was the predominant radical. To promote the Fe2+ activator effect, the effect of hydroxylamine as a reducing agent was investigated. In chelating agents assisted Fe2+-persulfate oxidation, the addition of 2 mM of CA and MA enhanced 2,4-D degradation. In contrast, EDTA and OA inhibited the 2,4-D removal due to steric hindrance effect.

• 한국균학회지
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• 제42권2호
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• pp.165-169
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• 2014

도토리화분의 총 폴리페놀함량은 화분배지에 뽕나무버섯(Armillaria mellea) 배양한 발아액에서 가장 높았으며, 표고(Lentinula edodes) 발아액에서 가장 낮았다. 뽕나무버섯을 배양한 발아액 중에서 동결건조 화분의 발아액이 정제화분과 저온초미분쇄화분의 발아액보다 총 폴리페놀함량이 많았다. 또한 동결건조 화분의 뽕나무버섯 발아액은 물추출액보다 총 폴리페놀함량이 1.4배 높았다. 도토리화분의 DPPH radical 소거능은 뽕나무버섯 발아액에서 가장 높았으며, 표고 발아액에서 가장 낮았다. 동결건조 화분의 뽕나무버섯 발아액은 DPPH radical 소거능이 물추출보다 2~4배 높았다. 수집된 꿀벌화분은 알갱이 형태이며, 꿀벌의 분비물을 제거한 순수 화분은 분말형태로 크기는 0.1~0.003 mm 정도이다. 화분의 전자현미경 구조는 도토리화분은 단립이며 모양은 장구형(prolate)이고 극면상은 난형이다. 발아구는 3구형이며 비교적 짧고 곧은 주름이 있다. 표면은 과립상(verrucate) 또는 미립상(scabrate)으로 불규칙한 돌기가 있다. 저온초미분쇄한 화분은 세포벽이 파쇄 또는 절단되었으며, 동결건조한 화분에서는 세포벽이 파열되어 세포질이 나출되는 양상을 보였다. 표고를 접종한 도토리 화분의 세포 발아 형태는 공구(pore) 주변에 외피가 없는 다량의 발아세포가 형성되었으며, 뽕나무버섯을 접종한 화분배지에서의 세포 발아 형태는 화분에서 균사속과 유사한 발아관이 형성되고 그 끝에 발아세포가 형성되었다.

• 대한환경공학회지
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• 제36권8호
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• pp.528-533
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• 2014

현재 사람들은 환경오염에 대한 관심이 많으며 각종 오염물질로 오염된 실내의 공기질을 향상시키고자 노력한다. 건강하고 쾌적한 생활환경을 조성하는 것은 매우 중요한 문제다. 본 연구에서는 공기정화분야에서 최초로 녹색기술 인증을 받은 기술을 사용하여 실내공기오염의 주범인 악취물질의 제거 효율을 향상시키고자 하였다. 이 녹색기술은 광촉매를 사용한 기존의 공기정화 시스템에 적외선램프를 사용하여 오염원인 물질들과 OH라디칼의 반응성을 높여 산화반응이 보다 쉽게 일어나도록 한 기술이다. 기존의 공기정화기와 비교하여 적외선램프를 부착한 녹색기술의 효율을 평가하였을 때, 오염원인물질의 초기 농도와 원인물질 종류에 따라 분해 효율의 차이가 나타났다. 저농도의 경우 16.9%의 제거효율 향상이 관찰되었고, 고농도의 경우 13.2%의 제거효율이 향상되었다.

• 공업화학
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• 제27권4호
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• pp.433-438
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• 2016

본 연구에서는 CO, HCHO, $CH_3CHO$, PM10, PM2.5 등의 담배연기 내에 포함된 유해물질들의 농도를 지표로 광촉매와 필터로 구성된 공기정화장치를 부착한 흡연부스 내의 공기질을 평가하였다. 또한 광촉매에서 발생되는 OH 라디칼과 담배연기 내 가스상 유해물질들과의 반응성을 향상시켜 제거효율을 높이기 위해 적외선을 주사하였다. 공기정화장치와 필터를 활용한 흡연부스의 실험 결과, 시스템 가동 전보다 가스상 오염물질은 포름알데히드 포함 최대 85.2% 향상된 제거효율을 나타냈다. 처리 후의 미세먼지는 최대 89.4% 향상된 제거효율을 나타냈다.

• 한국환경보건학회지
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• 제36권4호
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• pp.313-322
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• 2010

The aim of this research was to apply experimental design methodology to optimization of conditions of electrochemical oxidation of Rhodamine B (RhB) and N, N-Dimethyl-4-nitrosoaniline (RNO, indicative of the OH radical). The reactions of electrochemical oxidation of RhB degradation were mathematically described as a function of the parameters of current ($X_1$), NaCl dosage ($X_2$) and pH ($X_3$) and modeled by the use of the central composite design. The application of response surface methodology (RSM) yielded the following regression equation, which is an empirical relationship between the removal efficiency of RhB and RNO and test variables in a coded unit: RhB removal efficiency (%) = $94.21+7.02X_1+10.94X_2-16.06X_3+3.70X_1X_3+9.05X_2X_3-{3.46X_1}^2-{4.67X_2}^2-{7.09X_3}^2$; RNO removal efficiency (%) = $54.78+13.33X_1+14.93X_2- 16.90X_3$. The model predictions agreed well with the experimentally observed result. Graphical response surface and contour plots were used to locate the optimum point. The estimated ridge of maximum response and optimal conditions for the RhB degradation using canonical analysis was 100.0%(current, 0.80 A; NaCl dosage, 2.97% and pH 6.37).

• Journal of Nutrition and Health
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• 제52권1호
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• pp.26-35
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• 2019

본 연구에서는 구기엽의 항산화 활성을 확인하고자 50%, 70%, 100% 에탄올 추출물과 100% 에탄올 추출물에서 클로로필을 제거한 시료를 포함하여 총 4종 시료의 항산화 활성을 비교하였다. 항산화능을 측정하기 위하여 총 폴리페놀 함량, DPPH와 ABTS radicals 소거능, FRAP assay를 통해 시료의 항산화능을 평가하였다. 또한 $H_2O_2$처리로 산화적 스트레스를 유발한 HepG2세포주에서 추출물 들이 세포보호 효과를 나타낼 수 있는지 알아보고자 ROS 생성, DNA fragmention, 세포의 항산화효소활성 (SOD와 catalase)을 측정하였다. 연구결과, 총 폴리페놀 함량, DPPH와 ABTS radicals 소거능, 그리고 FRAP value에서 모두 추출용매의 알코올 농도가 높을수록 증가하였고 클로로필 제거 시료가 제거 전 시료에 비하여 월등히 높았다(p < 0.05). HepG2세포에서 세포독성을 확인한 결과 모든 시료에서 $1,000{\mu}g/mL$까지 세포독성을 유발하지 않았다. 모든 추출물들은 $31.3{\mu}g/mL$ 농도부터 $H_2O_2$에 의해 증가한 ROS생성량을 농도 의존적으로 감소시키는 효과를 보였다 (p < 0.05). 모든 추출물은 $250{\mu}g/mL$의 농도로 배양액에 처리하였을 때 세포의 DNA 손상을 억제하는 효과를 보여주었다 (p < 0.05). 또한 $H_2O_2$처리한 세포에 비하여 추출물들을 함께 처리한 세포군의 SOD와 catalase 활성은 정상세포과 유사한 수준으로 강력한 보호효과를 보여주었다. 결론적으로 본 연구에서 사용한 구기엽 에탄올 추출물들은 항산화능이 높으며 고농도까지 세포독성을 보이지 않고 $H_2O_2$에 의해 손상된 간세포를 보호할 수 있는 효능을 가지고 있음을 확인할 수 있었다. 특히 클로로필 제거구기엽 에탄올 추출물은 항산화능이 높고 세포독성과 세포보호 효과가 클로로필 제거전 구기엽 에탄올 추출물과 유사하게 나타나 건강기능식품이나 화장품의 소재로 활용하기에 적절한 소재로 생각된다.

• Journal of Korean Neurosurgical Society
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• 제30권4호
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• pp.472-478
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• 2001

Objectives : The authors present a retrospective analysis of 100 consecutive adult patients harboring craniopharyngiomas who underwent microsurgical resection between 1981 and 1999 to assess the long-term outcome of surgical treatment and to determine the most optimal management strategy. Methods : The extent of surgical removal was divided into four categories ; GTR(gross total removal), RSTR(radical subtotal removal), STR(subtotal removal),and PR(partial removal). The median follow-up period was 50 months(4-198). CT scan and/or MR imaging and hormonal status were evaluated to the last follow-up. Results : Visual disturbance was the most common presentation, which was improved in 42 cases and aggravated in 19 cases following the operation. Hypopituitarism was detected in 56 patients preoperatively, 82 during the immediate postoperative period, and 76 at the last follow-up. Improvement of pituitary function was not observed in any of these patients. Twenty of 100 patients showed recurrence at the mean of 27 months(3 to 196). The median progression-free survival(PFS) time of all patients was 145 months and 5-year PFS rate was 74%. Five-year PFS rate of GTR or RSTR group(71%) was significantly higher than that of STR or PR group(30%)(p=0.01). Postoperative radiation therapy significantly prolonged the PFS from 94 months in non-radiation group to 182 months(p=0.002). However, there was no statistical difference in number of patients who required hormonal replacement therapy between radiation and non-radiation group. Conclusion : Visual disturbance can be improved by early diagnosis and surgical decompression. GTR or RSTR in selected patients is considered a proper surgical strategy. Post-operative radiation therapy for residual tumors must be considered, although the ideal timing of radiation therapy is to be determined.

• 한국환경보건학회지
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• 제21권3호
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• pp.102-106
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• 1995

This study was performed to examine factors affecting the decompostion of nondegradable polluants(trichloroethylene(TCE), phenol) using ultrasonic irradiation. The TCE and phenol, which are major hazard compounds causing environmental pollution, were not decomposable pollutants by conventional treatment. The results show that the oxidation and reduction reaction of ultrasound produced $H_2O_2$, $H^+$ and $OH^-$ radical, which decomposed pollutants of TCE and phenol in water. It was confirmed that the ultrasonic irradiation showed an excellent removal efficiency for the nondegradable pollutants than any other processes, utilized in the treatment of organic compounds in the industrial wastewater. Conclusively, these results suggest that ultrasonic irradiation may be highly useful for the treatment of wastewaters contaminated organic pollutants, which is difficult to treat economically by conventional process.

• 환경위생공학
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• 제10권1호
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• pp.76-84
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• 1995

This study was performed to examine the factors influenced on the decomposition of nondegradable organic pollutants( Tricholoroethylene,Benzene ) in aqueous by ultrasonic irradiation. The TCE( Tricholoroethylene ) and Benzene are major hazard compounds causing environmental Pollution and not decomposable substances by conventional treatment. The results shows that the oxidation and reduction reaction of ultrasonic Irradiation was formed the H$_{2}$O$_{2}$ , H$^{+}$ and OH$^{-}$ radical, and then theses was decomposed pollutants of TCE and Benzene in aqueous. We were conformed that the ultrasonic irradiation was excellent in removal efficiency of the nondegradable organic substances any other than processes and utilized the treatment of organic compounds in the industrial wastewater. Conclusively, these results suggest that ultrasonic irradiation may be extremely useful for the treatment of wastewater contaminated organic pollutants, which is difficult to treat economically by conventional treatment.