• 한국재료학회:학술대회논문집
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• 한국재료학회 2011년도 춘계학술발표대회
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• pp.57.1-57.1
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• 2011

The effects of relative humidity on the properties of the porous $ZrO_2$ ceramics were investigated in terms of the curing behavior of phenolic resin as a binder. The $ZrO_2$ powders containing 5wt% of phenolic resin were conditioned in a consistent chamber condition at a temperature of $50^{\circ}C$ and different humidity levels (25, 50, 75, and 95%) for 1 h. The exposure of humid atmosphere caused changes of density and microstructure in the green bodies. The higher level the powders were exposed to the humid atmosphere, the lower green density was obtained and the more irregular microstructure was observed due to aggregation by the curing of phenolic resin. After firing, the porosity of specimens has risen from 35.7% to 38.1% and Young's modulus has declined in response to the variation of green density. These results could be explained by the degree of resin cure which was associated with the area under the exothermic peak enclosed by a baseline of DSC thermogram curve. Also, the curing behavior of phenolic resin according to relative humidity has been confirmed by decrease of ether groups which have interacted with the phenolic-OH group and the hexamine as a curing agent. Consequently, it could be demonstrated that increase the relative humidity during fabrication of porous $ZrO_2$ diminished the compaction and properties of specimens after firing owing to curing of phenolic resin.

• 한국자원식물학회지
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• 제33권1호
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• pp.40-49
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• 2020

The objectives of this study were to evaluate total phenolic content (TPC) and individual phenolic compounds in leaves of perilla genetic resources, assess whether they could be used as distinguishing factor among germplasms, and evaluate their relationship with some quantitative and qualitative morphological characters. TPC and individual phenolic compounds were determined using Folin-Ciocalteu method and UPLC-PDA system, respectively. Wide variations in TPC (7.99 to 133.70 mgGAE/g DE), rosmarinic acid (ND to 21.05 mg/g DE), caffeic acid (ND to 1.17 mg/g DE), apigenin-7-O-diglucuronide (ND to 2.21 mg luteolin equivalent (mgLUE)/g DE), scutellarein-7-O-glucuronide (ND to 5.25 mg LUE/g DE), and apigenin-7-O-glucuronide (ND to 2.81 mg LUE/g DE) were observed. Intensities of green pigment at abaxial and adaxial leaf surfaces were positively correlated with phenolic compounds whereas leaf length and width had negative correlation. Purple pigmented accessions were shorter in leaf length and width but exhibited higher amount of phenolic compounds compared to green pigmented accessions in most cases. Leaf shape was not related with content of phenolic compounds, color of leaves, and length/width of leaves. TPC and individual phenolic compounds along with morphological characters could be useful distinguishing factors for perilla genetic resources.

• 한국약용작물학회지
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• 제15권2호
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• pp.120-127
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• 2007

The objective of this research was to evaluate the ability of water and ethanol extracts from mulberry fruit (Morus alba L.) to influence the inhibitory activity of angiotensin converting enzyme (ACE) and xanthine oxidase(XOase). The total phenol contents and sixteen phenolic compounds were investigated in water and ethanol extracts. In order to understand the factors responsible for the potent antioxidant and antihypertensive ability of mulberry, it has been evaluated for anti-oxidative activity using Fenton's reagent/ethyl linoleate system and for free radical scavenging activity using the 1,1-diphenyl-2-picryl hydrazyl free radical generating system. The total phenol contents and total of phenolic compounds in ethanol extract showed higher levels than water extract in mulberry fruit six phenolic compounds (chlorogenic acid, narigin, syringic acid, quercetin, naringenin, kampferol) has a higher individual phenolic compound content in the 60% ethanol extraction than 80% ethanol extract. The inhibitory activity on angiotensin converting enzyme (ACE) were highest in 80% ethanol extract (9.0%). Also, activity of xanthine oxidase(XOase) inhibition appeared highest in 80% ethanol extracts and correlated well with the total phenolic content, which was modulated by the concentration of individual phenolic compounds. This result revealed, that strong biological activity was caused by specific phenol compound contents. Utilization of water and ethanol extracts from mulberry fruit are expected to be good candidate for development into source of free radical scavengers and anti-hypertentive activity

• 농업과학연구
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• 제11권2호
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• pp.295-302
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• 1984

저장 홍, 백삼 중의 Phenol계 화합물의 함량 및 항산화 활성을 측정하여 다음과 같은 결과를 얻었다. 1. 홍, 백삼중은 유리형 Phenol계 화합물의 함량은 결합형 보다 적었다. 2. 유리 Phenol계 산의 함량은 저장기간이 긴것 일수록 적었으나 결합형의 phenol 산의 함량은 별차이가 없었다. 3. 홍, 백삼중 전체 Phenol계 화합물의 50~80%를 차지하는 maltol의 함량은 홍삼과저장기간이 오랠수록 많았다. 4. 항산화 활성은 백삼에 비하여 홍삼이 강하였으나 저장기간에 따르는 차이는 인정되지 않았다.

• 한국식품저장유통학회지
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• 제19권5호
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• pp.735-743
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• 2012

자색고구마는 항당뇨, 항염증, 및 항산화 활성 등의 다양한 생리활성 효과가 있다. 본 연구에서는 자색고구마의 볶음 처리 후 DPPH, ABTs 및 FRAP를 분석하여 항산화 활성을 비교하였다. 부가적으로 우리는 볶음 처리에 의한 자색 고구마의 항산화 활성 변화 요인을 확인하기 위해 총 phenolics와 flavonoids 함량, 갈변물질 및 phenolic acids 함량을 측정하였다. 볶은 자색고구마는 볶지 않은 자색고구마보다 상당히 높은 항산화 활성을 나타내었다. 특히, $200^{\circ}C$에서 10분간 볶음처리 한 자색고구마는 다른 처리 조건들보다 높은 항산화 활성을 나타내었다. 볶음 처리 후 총 phenolic와 flavonoid 함량, 갈변물질 및 phenolic acids 함량이 현저하게 증가하였고, 이에 상응하여 항산화 활성이 증가하였다. 이 결과로부터 볶음 처리한 자색고구마는 식품에서 잠재적인 천연 항산화제로 사용할 수 있을 것으로 판단되었다.

• Applied Biological Chemistry
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• 제45권3호
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• pp.162-167
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• 2002

밤 삽피의 천연 항산화제로서의 이용 가능성을 검토하기 위하여 밤 삽피로부터 유리형(EPA), 에스데르형(EPA), 결합형(BPA) 페놀산 획분을 분리하였다. 각 획분의 수율은 유리형 0.794%, 에스테르형 1.236%,결합형이 1.937%였으며 이중 페놀성 화합물의 함량은 에스테르형이 65.19%로 가장 높았다. Gas chromatography로 각 획분의 페놀산의 조성과 함량을 조사한 결과 유리형 획분에서 gallic acid(4.63%), ellagic acid(3.49%), salicylic acid(3.19%), gentisic acid(1.5%)가, 에스테르형 획분에서 gallic acid(13.4%), ellagic acid(11.6), protocatechuic acid(0.9%)가 주요 페놀산으로 확인 되었으며,결합형 획분에서는 gallic acid는 확인되지 않고 다른 획분에 비하여 sinapic acid(1.33%)가 높은 함량을 보였다. 이들 획분의 항산화성을 DPPH 라디칼 소거능, hydroxyl radical 소거능, 지질과산화물 생성 억제 시험으로 조사한 결과 유리형, 에스데르형, 결합형 획분의 순으로 항산화 활성이 우수한 것으로 조사되었다.

• 한국자원식물학회지
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• 제27권6호
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• pp.610-621
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• 2014

Phenolic compounds such as isoflavones contribute to the antioxidant properties of soybean. This study investigated differences in the phenolic content and antioxidant activity of ten soybean cultivars grown in two different locations in Korea. We observed a wide range of variation in total isoflavone and phenolic content by location and cultivar. The total isoflavone content of cultivars grown at Pyeongchang (sub-highland) was significantly higher than that in cultivars grown at Gangneung (lowland). In contrast, the total phenolic content of cultivars grown at Gangneung was greater than that of cultivars grown at Pyeongchang. The radical scavenging activity of DPPH was similar to that of the total phenolic content rather than that of the total isoflavone content. These results suggest that antioxidant activity of soybean was associated with phenolic compounds rather than isoflavones. To identify the individual antioxidant components, we used an on-line HPLC-$ABTS^+$-based assay system, ESI/MS, and NMR. The results showed that the strongest antioxidant activity was linked to epicatechin.

• 한국식품영양과학회지
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• 제32권6호
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• pp.948-951
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• 2003

흑미(수원 415호)의 페놀화합물을 유리형과 결합형으로 분리하여 추출한 결과, 시료 100 g당 각각 845.4 및 401.6 mg 으로서 유리형 페놀화합물이 결합형보다 2배 이상 함량이 높았으며 항산화활성도 우수하였다. 유리형 페놀화합물을 용매 분획하여 각 분획의 페놀화합물 함량과 항산화활성을 측정한 결과, butanol 분획에서 가장 높은 페놀화합물 함량과 항산화활성이 관찰되었다. EDA, LPI 및 BAHI방법으로 butanol 분획의 항산화활성을 측정한 결과, butanol 분획의 hydroxy 라디칼 소거능력은 대조군으로 사용한 BHT와 $\alpha$-tocopherol보다는 우수하였으나, linoleic acid를 기질로 한 과산화물 생성억제능은 낮은 것으로 조사되었다. 또한 DPPH 라디칼 소거능의 경우, butanol 분획은 $\alpha$-tocopherol보다는 2배 이상 높았으나 BHT보다는 다소 떨어지는 것으로 나타났다. 따라서 흑미 페놀화합물의 항산화기작은 라디칼 소거작용에 기인하는 것이며 산화의 중간 단계의 과산화물 생성 억제력은 낮은 것으로 사료된다.

• Environmental Engineering Research
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• 제24권1호
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• pp.127-136
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• 2019

Land application of treated palm oil mill effluent (TPOME) could be used as an alternative tertiary wastewater treatment process. However, phenolic compounds in TPOME might be leached to the environment. This study investigated the ability of grasses on reducing phenolic compounds in the leachate after TPOME application. Several pasture grasses in soil pots were compared after irrigating with TPOME from stabilization ponds, which contained 360-630 mg/L phenolic compounds. The number of soil bacteria in planted pots increased over time with the average of $10^8CFU/g$ for mature grasses, while only $10^4-10^6CFU/g$ were found in the unplanted control pots. The leachates from TPOME irrigated grass pots contained lower amounts of phenolic compounds and had lower phytotoxicity than that of control pots. The phenol removal efficiency of grass pots was ranged 67-93% and depended on grass cultivars, initial concentration of phenolic compounds and frequency of irrigations. When compared to water irrigation, TPOME led to an increased phenolic compounds accumulation in grass tissues and decreased biomass of Brachiaria hybrid and Brachiaria humidicola but not Panicum maximum. Consequently, the application of TPOME could be conducted on grassland and the grass species should be selected based on the utilization of grass biomass afterward.

• Composites Research
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• 제33권6호
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• pp.329-335
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• 2020

본 연구에서는 각각에 다른 연화점을 갖는 석유계 피치의 열 유변학적 특성을 연구하였으며, 이를 함침용 페놀수지에 석유계 피치를 첨가하여 B-stage 형태의 페놀수지/석유계 피치 혼합물을 제조하였다. 그 결과, 연화점이 다른 석유계 피치는 QI의 함량이 증가할수록 피치의 유동성이 감소하였고, 고체의 점탄성 특성을 나타내었다. 또한, 다른 연화점을 갖는 석유계 피치를 페놀수지에 첨가함으로써, 페놀수지의 경화거동과 열 유변학적 특성에 미치는 영향에 대해 고찰하였을 때, 다른 연화점의 석유계 피치를 첨가함에 따라 페놀수지의 경화속도 및 경화거동을 조절할 수 있었으며, 이 중 P-Pitch 2가 첨가된 페놀수지 혼합물의 경우 동일한 경화 온도조건에서 다른 혼합물에 비해 유동성이 높은 것을 확인할 수 있었다.