• Korean Journal of Food Science and Technology
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• v.38 no.3
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• pp.331-336
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• 2006

Effects of high temperature and pressure treatment on garlic (Allium sativum L.) treated at 110, 120, 130, 140, and $150^{\circ}C$ for 1, 2, 3, 4, and 5 hr were evaluated by investigating changes in antioxidant activities, and total polyphenol, total flavonoid, and 5-hydroxymethyl-2-furaldehyde (5-HMF) contents of garlic juice. Antioxidant activities, and total polyphenol, total flavonoid, and 5-HMF contents increased with increasing treated temperature and time. $IC_{50}$ (1.952 mg/g) was achieved at $150^{\circ}C$ for 4 hr, 50 times higher than untreated garlics. Highest total polyphenol content was 18.155 mg/g at $140^{\circ}C$ and 2 hr, seven times higher than untreated garlics. Highest total flavonoid content was $532.73\;{\mu}g/g$ at $150^{\circ}C$ and 1 hr, sixteen times higher than untreated garlics. 5-HMF content was highest (7,765.9 ppm) at $150^{\circ}C$ and 2 hr. Correlation coefficients among antioxidant activities, and total polyphenol, total flavonoid, and 5-HMF contents were very high (p<0.01).

• Journal of Soil and Groundwater Environment
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• v.10 no.5
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• pp.45-51
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• 2005

The sorption/desorption characteristics of phenanthrene on the natural manganese oxide (NMD) were investigated in the presence of phenolic compounds. 4-chlorophenol (4-CP) was effectively oxidized by NMD catalyzed reaction and transformed into humic-like macromolecular compound through inter-or cross-coupling reaction between byproducts. As 4-CP was degraded with time, sorbed amount of phenanthrene on NMD was significantly increased, resulting from the formation of oxidative coupling products. These results imply that NMD can be used for simultaneous treatment of phenolic contaminants and polycyclic aromatic hydrocarbons (PAHs) in soils, sediments, or water. Also, sorbed phenanthrene on NMD in the presence of 4-CP showed high degree of desorption resistance, indicating that sequestration process of phenanthrene was ongoing with time.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.9
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• pp.27-33
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• 2016

Phenolic resin has excellent heat resistance and good mechanical properties as a thermosetting resin. However, its thermosetting characteristics cause it to produce a non-recyclable waste in the form of sprue and runner which is discarded and represents up to 15~20% of the overall products. Forty thousand tons of phenolic resin sprue and runner are disposed of (annually). The (annual) cost of such domestic waste disposal is calculated to be 20 billion won. In this study, discarded phenol resin scraps were pulverized and treated by silanes to improve their interfacial adhesion with HDPE. The sizes of the pulverized pulverulent bodies and fine particles were (100um~1000um) and (1~100um), respectively. The pulverized phenol resin was treated with 3-(methacryloyloxy) propyltrimethoxysilane and vinyltrimethoxy silane and the changes in its characteristics were evaluated. The thermal properties were evaluated by DSC and HDT. The mechanical properties were assessed by a notched Izod impact strength tester. When the silane treated phenol resin was added, the heat distortion temperature of HDPE increased from $77^{\circ}C$ to $96^{\circ}C$ and its crystallinity and crystallization temperature also increased. Finally, its impact strength and tensile strength increased by 20% and 50%, respectively, in comparison with the non-treated phenol resin.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.4
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• pp.423-429
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• 2008

Application of manganese-impregnated activated carbon(Mn-AC) in the treatment of synthetic wastewater containing both organic and inorganic contaminants was investigated. Phenol and As(III) was used as representative organic and inorganic contaminants, respectively. When the stability of Mn-AC at acidic condition was evaluated with variation of solution pH ranging from 2 to 4, Mn-AC was unstable below pH 3, while negligible dissolution of Mn was observed above pH 4. This stability test suggests a plausible applicability of Mn-AC in the treatment of wastewater above pH 4. Compared to AC-alone, the adsorption rates of phenol as well as adsorbed amounts of phenol by Mn-AC were slightly decreased due to the decrease of the surface area by impregnation. The maximum adsorbed amount of phenol by Mn-AC was corresponds to 75% of that by AC-alone from the adsorption isotherm study. The oxidation efficiency of As(III) by Mn-AC was greater than that by AC-alone at lower pHs while reverse trend was observed as pH increased above 7. From this work, it was found that Mn-AC could be used in the simultaneous treatment of both phenol and As(III).

• Horticultural Science & Technology
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• v.32 no.3
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• pp.353-358
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• 2014

Hot water dipping test was conducted for chicon to restrict red discoloration of its basal part which impairs the product value during sales. Hot water dipping treatment was given to chicon for 4 min and for 8 min at $38^{\circ}C$ and for 2 min and 4 min at $42^{\circ}C$, and for 1 min and 2 min at $45^{\circ}C$, along with control (for one min at $20^{\circ}C$). The red discoloration indices of basal part of chicon during sensory evaluation on the sixth day of storage under the storage temperature at $10^{\circ}C$ was lower at $42^{\circ}C$ for 2 min, $42^{\circ}C$ for 4 min and $45^{\circ}C$ for 1 min treatments. The color change value of the basal part in chicon measured by colorimeter showed that the lowest ${\Delta}a^*$ and ${\Delta}h$ were maintained in the basal part of chicon treated at $42^{\circ}C$ for 2 min. Whereas, color changes in $42^{\circ}C$ for 2 min and $45^{\circ}C$ for 1 min treatments were significantly low as compared with that of control. The contents of total phenolic compounds which are the substances that cause red discoloration of basal part in chicon were lowest at $42^{\circ}C$ for 2 min, $42^{\circ}C$ for 4 min and $45^{\circ}C$ for 1 min treatments. The activity of phenylalanine ammonia lyase (PAL) resposible for in the synthesis of phenolic substances was the least in $42^{\circ}C$ for 2 min treatment. Whereas, PAL activity of the chicons treated a t $42^{\circ}C$ for 2 min and at $45^{\circ}C$ for 1 min were significantly lower than that of control. However, red discoloration was progressed as similar level with that of control in the basal part of chicon at $45^{\circ}C$ for 2 min. The contents of total phenolic compounds and PAL activity in this treatment were not significantly different from those in control. The polyphenol oxidase (PPO) activity which causes red discoloration of cut tissues was low in all the treatments including $42^{\circ}C$ and $45^{\circ}C$ treatment at which no inhibition effects of the red discoloration of basal part of chicon were observed. When the correlation coefficient between each investigated index was tested, most of them showed high correlation except the PPO activity and particularly and the red discoloration index and sensory evaluation ${\Delta}h$ values, and PAL activity and total phenolic compounds content were $r=0.927^{**}$, and $r=0.942^{**}$, respectively.

• Composites Research
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• v.25 no.3
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• pp.76-81
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• 2012

Atmospheric pressure plasma treatment on carbon nanotube (CNT) surfaces was performed to modify reinforcement effect and interfacial adhesion of carbon fiber reinforced CNT-phenolic composites. The surface changes occurring on CNT treated with plasma were analyzed by using Fourier transform infrared spectroscope (FT-IR). The significant improvement of wettability on CNT was confirmed by static contact angle test after plasma treatment. Such plasma treatment resulted in a decrease in the advancing contact angle from $118^{\circ}$ to $60^{\circ}$. The interfacial adhesion between carbon fiber and CNT-phenolic composites increased by plasma treatment based on apparent modulus test results during quasi-static tensile strength. Furthermore, the proposed database offers valuable knowledge for evaluating interfacial shear strength (IFSS).

• Analytical Science and Technology
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• v.20 no.3
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• pp.193-197
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• 2007

In this study, the effect of metal treatment on granular activated carbon (GAC) was investigated in the context of phenol adsorption. Cobalt(II) nitrate, and zinc(II) nitrate solution were used for metal treated. The specific surface area and the pore structure were evaluated from nitrogen adsorption data at 77 K. The phenol adsorption rates onto GAC were measured by UV-Vis spectrophotometer. Iodine adsorption capacity of Co-GAC is much better then that of the GAC. The Co-GAC with mesopore is more efficient than other adsorbents for the adsorption of polymer such as methyleneblue. The adsorption capacity of reference-GAC and metal-GAC were increased in order of Co-GAC>Zn-GAC>Reference-GAC, in spite of a decrease in specific surface area which was resulted from pore blocking by metal.

• Journal of Plant Biotechnology
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• v.32 no.3
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• pp.225-231
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• 2005

This study was initiated to investigate the impacts of methyl jasmonate (MeJA) on adventitious root growth of Panax ginseng, the production of secondary metabolites, such as ginsenosides and phenolic compounds, and antioxidative activity. Among various concentrations of MeJA, $100\;{\mu}M$ MeJA increased the ginsenosides accumulation to 26.6 mg/g dry wt, about 8 times higher than the control in ginseng adventitious roots (GAR). In addition, $50\;{\mu}M$ MeJA increased the accumulation of phenolic compounds to 0.38 mg/g dry wt, about 3 times higher than control in GAR. This MeJA treatment was more effective in conditioned medium (CM) which obtained in bioreactor after 40 days of culture than in fresh medium (FM). Treatment of $100\;{\mu}M$ MeJA in CM increased the accumulation of ginsenosides (1.7 times) and phenolic compounds (1.2 times) more than in FM, respectively. Consequently, these high accumulation of ginsenosides and phenolic compounds by MeJA led to increase the antioxidative activities expressed to the DPPH scavenging activity (over $78.3\%$). The DPPH scavenging activity in control was $45.5\%$.

• Korean Journal of Weed Science
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• v.30 no.4
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• pp.396-404
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• 2010

Phenolic compounds, which are products of secondary metabolism, have been demonstrated to be widespread growth substances in plants. The objectives of this study were to identify the phenolic compounds in common ragweed (Ambrosia artemisiifolia var. elatior) by HPLC and to evaluate their effects on germination and seedling growth of three weed species. Under controlled conditions in Petri dishes at $25^{\circ}C$, $10^{-3}$ and $10^{-4}$ M solutions of phenolic compounds were evaluated in seed germination tests. Four phenolic compounds (caffeic acid, O-coumaric acid, ${\rho}$-coumaric acid and ferulic acid) in common ragweed plant were identified and their concentration was increased from the stage before flowering through full flowering stage. Treatment of O- and ${\rho}$-coumaric acids delayed the seed germination of Digitalia ciliaris, while the treatment of caffeic acid delayed the seed germination of Echinochloa crus-galli. In time to 50% germination ($T_{50}$), phenolic compounds at $10^{-4}$ M promoted in Cyperus microiria and E. crus-galli but the level of $10^{-3}$ M delayed the $T_{50}$ of those weeds. The O-coumaric acid inhibited seed germination and seedling growth of the tested weeds and especially it perfectly inhibited the root growth of E. crus-galli.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2020.12a
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• pp.69-69
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• 2020

소엽(Perilla frutescens var. acuta)은 흔히 차조기, 자소엽 등으로 불리며, 식재료나 약재로 이용된다. 최근 들어 자소엽을 향장 원료로 활용하고자 하는 시도가 이루어지고 있다. 따라서 유기자재 처리를 통해 향장원료 자소엽의 고품질 생산을 위하여 본 시험을 실시하였다. 전북 농업기술원 허브산채시험장에서 육묘한 종묘를 2020년 5월 노지 포장에 주간 간격 50cm 한줄 재배로 정식하였다. 처리는 규산염(성분량 20%), 키토산(성분량 5%)가 함유된 자재를 각각 500배, 1,000배 희석하여 6월 21일, 8월 3일, 8월 23일 총 3회에 걸쳐 압축 분무기를 이용해 작물이 충분히 적셔지도록 살포하였으며, 무처리구는 물을 살포하였다. 초장, 초폭, SPAD, 생체중, 건물중을 조사하였으며 잎과 꽃의 총 폴리페놀 함량, 총 플라보노이드 함량, FRAP(철환원 항산화력) 활성 ABTS+ 라디칼 저해활성을 측정하였다. 생육특성 중 초장과 초폭은 처리간 유의성은 없었으나 무처리, 규산염 500배, 키토산 1,000배 처리에서 대체로 높았으며, SPAD는 키토산 1,000배가 가장 양호하였다. 수량성은 모든 자재 처리구가 무처리구보다 많았으며, 지상부 생체중은 무처리 대비 키토산 1,000배는 14.1%, 건물중은 무처리 대비 11.9%로 키토산 1,000배 처리가 수량성이 가장 많았다. 총 폴리페놀 함량은 꽃보다 잎에서 더 높은 수치로 나타났으며, 잎의 폴리페놀 함량은 규산염 500배 처리에서 가장 많았다. 꽃은 1,000배 처리에서 가장 높았다. 총 플라보노이드 함량은 꽃이 잎보다 높았으며, 잎은 규산염 500배 처리, 꽃은 키토산 1,000배 처리에서 함량이 가장 많았다. FRAP 활성은 잎의 경우 규산염 500배 처리에서 높았으며, 꽃의 FRAP 활성은 키토산 1,000배에서 좋았으나 처리 간의 차이는 크지 않았다. 자소엽 잎의 ABTS+ 라디칼 저해 활성은 규산염 500배 처리에서 가장 높았으며, 꽃은 경우 무처리에 비하여 자재 처리가 높았으며, 500배보다 1,000배 처리에서 높은 라디칼 저해 활성을 보였다. 이상의 결과, 자소엽 유기자재 처리는 무처리보다 대체로 수량성과 항산화 활성이 높았으나 추가적으로 적정농도 구명 후 경제성 분석이 필요할 것으로 판단된다.