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Effect of Phenolic Mediators and Humic Acid on the Removal of 1-Indanone Using Manganese Oxide (망간산화물(Birnessite)을 이용한 1- Indanone 제거 시 페놀계 반응매개체와 휴믹산(HA) 영향 평가)

  • Choi, Chan-Kyu;Eom, Won-Suk;Shin, Hyun-Sang
    • Journal of Korean Society of Environmental Engineers
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    • v.34 no.7
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    • pp.445-453
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    • 2012
  • An investigation for removal of 1-indanone (1-ID), which were commonly produced from the biological and/or chemical treatment and natural weathering of the PAHs-contaminated soils, via oxidative transformation mediated by birnessite in the presence of various phenolic mediators is described. This study also examines the potential effect of the natural occurring substance humic acid (HA) on the oxidative transformation. The experiment was carried out in aqueous phase as a batch test (10 mg/L 1-ID, 0.3 mM phenolic mediators, $1.0g/L\;{\delta}-MnO_2$, at pH 5). All of the 11 tested phenoilic mediators belong to the group of natural occurring phenols and are widely used as model constituents of humic substances. From the results of HPLC analysis, it is demonstrated that 1-ID was not reactive to birnessite itself, but it can be effectively removed in birnessite-mediated cross coupling reactions in the presence of the phenolic mediators. The percent removals of 1-ID after 2 day incubation were ranged from 9.2 to 71.2% depending on the phenolic mediators applied. The initial rate constant ($K_{int}$, $hr^{-1}$) values for the 1-ID removals obtained from the pseudo-first-order kinetic plots also widely ranged from 0.18 to 15.0. Results of the correlative analysis between the removal efficiencies and structural characteristics of phenolic mediators indicate that the transformation of the 1-ID was considerably enhanced by the addition of electron-donating substituents (e.g., -OH, $-OCH_3$) at the benzne ring, and much less enhanced by the addition of electron-withdrawing substituents (e.g., -COOH, -CHO). The presence of HA showed that removal efficiencies of 1-ID in the birnessite-phenolic mediator systems decreased with increasing HA concentrations. However at low concentration of HA (< 2 mg/L), it caused some enhancement in the removals of 1-ID as compared to the control.

The Allelopathic Effects of Aqueous Extracts of Hypochaeris radicata L. on forage Crops (서양금혼초(Hypochaeris radicata L.)의 수용추출물이 사료작물에 미치는 allelopathy 효과)

  • Kim Og-Yim;Park Sun-Ill;Jung Ill-Min;Ha Sang-Young
    • Journal of Life Science
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    • v.15 no.6 s.73
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    • pp.871-878
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    • 2005
  • This experiment was performed to examine the allelopathy effect of allelochemical substance on the crop plants. According to the experiment of the allelochemical substances in Hypochaeris radicata by HPLC, there are the differences at each part of plants. However, it is ascertained that there are 14 kinds of phenolic compounds ingredients that are $\rho$-hydroxybenzoic acid, chlorogenic acid, catechin, caffeic acid, syringic acid, salicylic acid, $\rho$-coumaric acid, ferulic acid, naringin, hesperidin, myricetin, trans-cinnamic acid, quercetin and naringenin. The chemicals like caffeic acid, ferulic acid, and naringenin are commonly included. The result of the chemical experiment shows that there are the differences at each season and part of plants. The leaves in May and blossoms and roots in July contain lots of phenolic acids. It is very high contents such as salicylic acid 2085.6 ${\mu}g/g$ and quercetin 1522.0 ${\mu}g/g$, especially in roots of plants. The result on the growth of crop plants treated by the aqueous extract of Hypochaeris radicata shows that the value of the control group and the test group are same in some cases. However, because the treat value of test group is towel'than that of control group in all items of the experiment, it is cofirmed that the growth of crop plants was inhibited and that the inhibitory effect was increased as its density of treatment was increased. The result of change in quantity shows that there are the differences at each kind of crop plants, but the inhibitory effect was increased as its concentration of treatment was increase with entire. As results, it is confirmed that H. radicata has the allelopathy effect to the crop plants. Especially the inhibitory effect on growth is high in gramineous crop, italian ryegrass and leguminous crop. purple alfalfa.

A Study on the Flammability and Combustion Risk of Biodiesel Mixture (바이오디젤 혼합물의 인화 및 연소 위험성에 관한 연구)

  • Kim, Ju Suk;Ko, Jae Sun
    • Journal of the Society of Disaster Information
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    • v.17 no.1
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    • pp.10-24
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    • 2021
  • Purpose: The purpose of this study is to determine the dangers of biodiesel and general diesel mixtures currently used as alternative fuels by equipment (tag method and penski Marten method) and to determine the difference between flash point and combustion point (closed, open) according to test methods. It is intended to be used as a reference material for identification and evaluation of firecausing substances by confirming the risk of mixtures by comparative analysis and measurement, and establishing a risk assessment method for chemical substances. Method: Flash point test method and result treatment were tested based on ASTM and KS M mode, which are tag sealing and pen schematense test methods used as flash point and combustion point test methods for crude oil and petroleum products. The manufacturer of the equipment used in this experiment was a test equipment that satisfies the test standards of KS M 2010 with equipment produced by TANAKA of Japan. The flash point and combustion point were measured, and the flash point according to the test method of biodiesel and general diesel mixture ( Closed, open), and the ignition point of a mixture of biodiesel and general diesel was compared and analyzed for ignition risk compared with conventional diesel. Results: Looking at the experimental results, first, as an analysis of the risk of flammability of the mixture, the flash point of a substance containing 70% biodiesel was found to be about 92℃ based on general diesel with a flash point of 64.5℃, and gasoline and biodiesel or When the biodiesel mixture was synthesized, it was confirmed that the flash point tends to decrease. In addition, the difference between the flash point and the combustion point was analyzed as about 20 ~ 30℃, and when a small amount of gasoline or methanol was mixed, the flash point was lowered, but it was confirmed that the combustion point was similar to that of the existing mixture. Conclusion: In this study, in order to secure the effectiveness of the details of the criteria for judging dangerous materials in the existing Dangerous Materials Safety Management Act, and to secure the reliability and reproducibility of the judgment of dangerous materials, we confirm the criteria for judging the risk of the mixture through an experimental study on flammable mixtures. It will be able to provide reference data for experimental criteria for flammable liquids that are regulated in the field. In addition, if this study accumulates know-how on experiment by test method, it is expected that it can be used as a basis for research on risk assessment and research on dangerous goods.

Anti-listeria Activity of Lactococcus lactis Strains Isolated from Kimchi and Characteristics of Partially Purified Bacteriocins (김치에서 분리한 Lactococcus lactis 균주의 항리스테리아 활성 및 부분 정제된 박테리오신의 특성)

  • Son, Na-Yeon;Kim, Tae-Woon;Yuk, Hyun-Gyun
    • Journal of Food Hygiene and Safety
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    • v.37 no.2
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    • pp.97-106
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    • 2022
  • Listeria monocytogenes (L. monocytogenes) is one of gram-positive foodborne pathogens with a very high fatality rate. Unlike most foodborne pathogens, L. monocytogenes is capable of growing at low temperatures, such as in refrigerated foods. Thus, various physical and chemical prevention methods are used in the manufacturing, processing and distribution of food. However, there are limitations to the methods such as possible changes to the food quality and the consumer awareness of synthetic preservatives. Thus, the aim of this study was to evaluate the anti-listeria activity of lactic acid bacteria (LAB) isolated from kimchi and characterize the bacteriocin produced by Lactococcuslactis which is one of isolated strains from kimchi. The analysis on the anti-listeria activity of a total of 36 species (Lactobacillus, Weissella, Lactobacillus, and Lactococcus) isolated from kimchi by the agar overlay method revealed that L. lactis NJ 1-10 and NJ 1-16 had the highest anti-listeria activity. For quantitatively analysis on the anti-listeria activity, NJ 1-10 and NJ 1-16 were co-cultured with L. monocytogenes in Brain Heat Infusion (BHI) broth, respectively. As a result, L. monocytogenes was reduced by 3.0 log CFU/mL in 20 h, lowering the number of bacteria to below the detection limit. Both LAB strains showed anti-listeria activity against 24 serotypes of L. monocytogenes, although the sizes of clear zone was slightly different. No clear zone was observed when the supernatants of both LAB cultures were treated with proteinase-K, indicating that their anti-listerial activities might be due to the production of bacteriocins. Heat stability of the partially purified bacteriocins of NJ 1-10 and NJ 1-16 was relatively stable at 60℃ and 80℃. Yet, their anti-listeria activities were completely lost by 60 min of treatment at 100℃ and 15 min of treatment at 121℃. The analysis on the pH stability showed that their anti-listeria activities were the most stable at pH 4.01, and decreased with the increasing pH value, yet, was not completely lost. Partially purified bacteriocins showed relatively stable anti-listeria activities in acetone, ethanol, and methanol, but their activities were reduced after chloroform treatment, yet was not completely lost. Conclusively, this study revealed that the bacteriocins produced by NJ 1-10 and NJ 1-16 effectively reduced L. monocytogenes, and that they were relatively stable against heat, pH, and organic solvents, therefore implying their potential as a natural antibacterial substance for controlling L. monocytogenes in food.

Study on High Sensitivity Metal Oxide Nanoparticle Sensors for HNS Monitoring of Emissions from Marine Industrial Facilities (해양산업시설 배출 HNS 모니터링을 위한 고감도 금속산화물 나노입자 센서에 대한 연구)

  • Changhan Lee;Sangsu An;Yuna Heo;Youngji Cho;Jiho Chang;Sangtae Lee;Sangwoo Oh;Moonjin Lee
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.28 no.spc
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    • pp.30-36
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    • 2022
  • A sensor is needed to continuously and automatically measure the change in HNS concentration in industrial facilities that directly discharge to the sea after water treatment. The basic function of the sensor is to be able to detect ppb levels even at room temperature. Therefore, a method for increasing the sensitivity of the existing sensor is proposed. First, a method for increasing the conductivity of a film using a conductive carbon-based additive in a nanoparticle thin film and a method for increasing ion adsorption on the surface using a catalyst metal were studied.. To improve conductivity, carbon black was selected as an additive in the film using ITO nanoparticles, and the performance change of the sensor according to the content of the additive was observed. As a result, the change in resistance and response time due to the increase in conductivity at a CB content of 5 wt% could be observed, and notably, the lower limit of detection was lowered to about 250 ppb in an experiment with organic solvents. In addition, to increase the degree of ion adsorption in the liquid, an experiment was conducted using a sample in which a surface catalyst layer was formed by sputtering Au. Notably, the response of the sensor increased by more than 20% and the average lower limit of detection was lowered to 61 ppm. This result confirmed that the chemical resistance sensor using metal oxide nanoparticles could detect HNS of several tens of ppb even at room temperature.

Comparison of Substance Change and Antibacterial Activity Before and After Fermentation Using Resource Plants for The Development of Natural Preservatives (천연방부제 개발을 위한 자원식물을 활용한 발효 전·후 물질 변화와 항균활성 비교)

  • Seo A Jung;Youn Ok Jung;Ga Hyeon Song;No Bok Park
    • Journal of Practical Agriculture & Fisheries Research
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    • v.25 no.1
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    • pp.20-35
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    • 2023
  • Chemical preservatives have a good effect on antibacterial activity, but many side effects on the human body have been reported. Recently, the development of natural preservatives that are harmless to the human body and have preservative functions and self-efficacy is active. In addition, in order to increase the absorption rate of natural products by the human body, the method of fermentation using strains is also increasing. Therefore, this study selected varieties that are harmless to the human body and have good antibacterial activity. 1. The yield of origin, thickness and solvent was investigated. Scutellaria baicalensis Georgi was made in China and received a yield of 21.88% from 50% ethyl alcohol extract. Salvia miltiorrhiza Bunge was made in Korea and received a yield of 25.62% from 50% ethyl alcohol extract. Dryopteris crassirhizoma Nakai was made in China and received a yield of 6.50% from 70% ethyl alcohol extract. 2. The solid fermentation with the S. baicalensis and S. miltiorrhiza with B. Subtilis yield gained 24.40%, 39.30%, and D. crassirhizoma obtained 11.10% yield when fermented with L. casei. 3. After the liquid fermentation, a clear zone of 9mm was identified for the S. aureus strain in the S. baicalensis, and the antibacterial activity was not confirmed in S. miltiorrhiza and D. crassirhizoma. 4. When the S. baicalensis was fermented with L. Casei, it showed high antibacterial activity in C. albicans and S. aureus. S. miltiorrhiza showed antibacterial activity in S. aureus when it was solid with S. cerevisiae. When the spectators were solid with L. casei and S. cerevisiae, antibacterial activity was high in E. coli and S. aureus. Overall, the antibacterial activity after fermentation was much higher than when fermented. 5. The change in active ingredients was baicalin 101.57, baicalein 28.26, and wogonin 5.33mg/g in the S. baicalensis that did not ferment solid. When solid fermentation with S. cerevisiae, the content of baicalinin with baicalin 94.31, baicalein 30.41, and wogonin 3.57mg/g was found to have increased. S. miltiorrhiza that was not fermented, salvianolic acid A was 1.82mg/g, and when fermented with S. cerevisiae, it increased to 5.70mg/g. The active ingredients of the spectators were flavaspidic acid AP, flavaspidic acid PB, flavaspidic acid AB, and flavaspidic acid BB.

Effects of Ojeoksangamibang on the Lipid Metabolism, Anti-oxidation and Concentration of Proinflammatory Cytokines in Rat Fed High Fat Diet (오적산가미방(五積散加味方)이 고지방식이 유도 비만쥐의 지질대사, 항산화계 및 전염증성 cytokine 생산에 미치는 영향)

  • Kong, In-Pyo;Park, Won-Hyung;Cha, Yun-Yeop
    • Journal of Korean Medicine Rehabilitation
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    • v.21 no.4
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    • pp.23-40
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    • 2011
  • Objectives: This study was designed to examine the effects of extracts of Ojeoksangamibang($W{\check{u}}j\bar{i}s\check{a}nji\bar{a}w\grave{e}if\bar{a}ng$) on the lipid lowering, anti-oxidation and concentration of proinflammatory cytokines and was investigated on hyperlipidemic rats. Methods: Male rats weighing $182.39{\pm}4.71g$ were fed high fat diet for 8 weeks and 36 rats(above 400 g) were divided into 4 groups. Each of 9 rats was divided a control group and experimental groups. We fed a control group of rats a basal diet and administered normal saline(100 mg/kg, 1 time/1 day) for 4 weeks. And we fed each experimental group of rats basal diet and administered an extract of Ojeoksangamibang($W{\check{u}}j\bar{i}s\check{a}nji\bar{a}w\grave{e}if\bar{a}ng$) extracts(100 mg/kg, 200mg/kg, 300 mg/kg, 300 mg/kg, 1 time/1 day) for 4 weeks. At the end of the experiment, the rats were sacrificed to determine their chemical composition. We measured lipid of plasma and liver, concentration of proinflmmatory cytokines, anti-oxidative activity and $TNF-{\alpha}$, Apo-B, Apo-E and leptin gene expression. Results: 1. Concentration of plasma free fatty(FFA) showed no significant difference in all the treatment groups. Concentration of plasma triglyceride(TG) showed a significant decrement in the 300 mg/kg in Ojeoksangamibang($W{\check{u}}j\bar{i}s\check{a}nji\bar{a}w\grave{e}if\bar{a}ng$) groups than that of control group. 2. Concentration of plasma total cholesterol showed a significant decrement in the 200 and 300 mg/kg in Ojeoksangamibang($W{\check{u}}j\bar{i}s\check{a}nji\bar{a}w\grave{e}if\bar{a}ng$) groups than that of control group. Concentration of plasma low density lipoprotein(LDL)-cholesterol showed a Significant decrement in the 300 mg/kg in Ojeoksangamibang($W{\check{u}}j\bar{i}s\check{a}nji\bar{a}w\grave{e}if\bar{a}ng$) groups than that of control group. Concentration of plasma high density lipoprotein(HDL)-cholesterol showed a significant increment in the 300 mg/kg in Ojeoksangamibang($W{\check{u}}j\bar{i}s\check{a}nji\bar{a}w\grave{e}if\bar{a}ng$) group. 3. Concentration of liver total cholesterol showed a tendence to decrease in Ojeoksangamibang($W{\check{u}}j\bar{i}s\check{a}nji\bar{a}w\grave{e}if\bar{a}ng$) groups. Concentration of liver TG showed a significant decrement in all Ojeoksangamibang groups than that of control group. 4. Concentration of plasma and liver thiobarbituric acid reactive substance(TBARS) showed a tendence to decrease in Ojeoksangamibang($W{\check{u}}j\bar{i}s\check{a}nji\bar{a}w\grave{e}if\bar{a}ng$) groups. 5. The values of glutathione peroxidase(GSH-Px), superoxide dismutase(SOD) and catalase(CAT) activity showed a significant increment in all Ojeoksangamibang($W{\check{u}}j\bar{i}s\check{a}nji\bar{a}w\grave{e}if\bar{a}ng$) groups than that of control group. 6. The values of plasma aspartate aminotransferase(AST) and alanine aminotransferase(ALT) activity showed no significant different in all treatment group. 7. Concentration of plasma $interleukin(IL)-1{beta}$ showed no significant difference in all the treatment groups. Concentration of plasma IL-6 showed a significant decrement in the 300 mg/kg in Ojeoksangamibang($W{\check{u}}j\bar{i}s\check{a}nji\bar{a}w\grave{e}if\bar{a}ng$) group than that of control group. Concentration of plasma tumor necrosis $factor-{\alpha}(TNF-{\alpha})$ a siginifant decrement in the 200 and 300 mg/kg in Ojeoksangamibang($W{\check{u}}j\bar{i}s\check{a}nji\bar{a}w\grave{e}if\bar{a}ng$) group than that of control group. However the concentration of plasma IL-10 in the 300 mg/kg Ojeoksangamibang($W{\check{u}}j\bar{i}s\check{a}nji\bar{a}w\grave{e}if\bar{a}ng$) groups showed a significant increment than that of control group. 9. In the analysis of reverse transcription-polymerase chain reaction(RT-PCR), gene expression of $TNF-{\alpha}$, Apo-B and Apo-E in the Ojeoksangamibang($W{\check{u}}j\bar{i}s\check{a}nji\bar{a}w\grave{e}if\bar{a}ng$) groups showed a lower expression than that of control group. However the gene expression of leptin showed no difference in the treatment groups. 10. The ratio of $TNF-{\alpha}$, Apo-B, and Apo-E per ${\beta}-actin$ expression in the Ojeoksangamibang($W{\check{u}}j\bar{i}s\check{a}nji\bar{a}w\grave{e}if\bar{a}ng$) groups showed a significant decrement than that of control group. However The ratio of leptin expression per ${\beta}-actin$ expression showed no significant difference among all the treatment groups. Conclusions: According to above results, in lowering lipid effect, anti-oxidation and control of pro-inflammatory cytokines production, Ojeoksangamibang($W{\check{u}}j\bar{i}s\check{a}nji\bar{a}w\grave{e}if\bar{a}ng$) gives effect.