• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.10
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• pp.1588-1593
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• 2015

Contents of phenolic acids, flavonoids, and anthocyanins of mulberries (Morus alba L.) cultivated in a greenhouse (GH) and open field (OF) were evaluated by HPLC during maturation. In the case of phenolic acids, caffeic acid ($96.37{\sim}824.00{\mu}g/g$), coumaric acid ($19.45{\sim}68.23{\mu}g/g$), ferulic acid ($4.50{\sim}18.66{\mu}g/g$), and sinapic acid ($15.61{\sim}29.27{\mu}g/g$) were detected. The major phenolic acid was caffeic acid, and its content increased in the initial stage and decreased in the last stage. The phenolic acid content of OF mulberries was higher than that of GH mulberries. Contents of two major flavonoids, quercetin, and kaempferol, were $44.17{\sim}1,661.73{\mu}g/g$ and $108.67{\sim}360.20{\mu}g/g$, respectively. Quercetin content decreased with maturation stage, whereas kaempferol content remained constant in GH mulberries but increased in OF mulberries. In the case of cultivation methods, quercetin content of OF mulberries was higher than that of GH mulberries. Contents of cyanidin, delphinidin, malvidin, and pelargonidin were $30.43{\sim}6,443.88{\mu}g/g$, $0{\sim}52.10{\mu}g/g$, $1.06{\sim}1,650{\mu}g/g$, and $1.92{\sim}401.97{\mu}g/g$, respectively. Anthocyanin content increased with maturation stage, and anthocyanin content of OF mulberries was higher than that of GH mulberries. OF mulberries in the last stage of maturation had higher contents of functional substances than other conditions.

• Composites Research
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• v.33 no.6
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• pp.329-335
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• 2020

In this study, the thermo-rheological behaivors of petroleum pitches with different softening points were studied, and a B-stage phenolic resins/petroleum pitches blends were prepared by adding petroleum pitches to the phenolic resins. As a result, the petroleum pitch with different softening points decreased the fluidity of the petroleum pitch as the Quinoline insoluble (QI) content increased and showed the viscous properties of the solid. In addition, the effect of adding petroleum pitches having different softening points on the thermo-rheological properties of phenolic resins was investigated. When petroleum pitch with a high softening point was added, the fluidity of the phenolic resin was reduced, and the hardening behavior was fast. It was possible to control the curing rate and curing behavior of the phenolic resin by adding petroleum pitches of different softening points. Among them, the phenolic resin mixture to which P-Pitch 2 was added has a higher fluidity than other blends under the same curing temperature condition.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.4
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• pp.457-467
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• 2020

Legumes are one of the largest families of crop plants and are widely consumed and produced for their nutritional and commercial benefits. Mung bean (Vigna radiata L.) is a legume crop that contains various functional compounds ; moreover, it has strong antioxidant properties and is becoming an increasingly important food crop. However, most previous studies on mung beans have focused on their primary metabolites. In this study, we investigated the composition and contents of phenolic compounds, fatty acids, soyasapogenol and tocopherol in mung beans cultivated in different regions and cultivated at different seeding dates. Material analysis was conducted using the following methods: LC-MS/MS, GC-FID and HPLC-ELSD. In total, 57 different samples were analyzed. Thirteen phenolic compounds were detected in mung beans. Of these, vitexin and isovitexin were the most abundant compounds, accounting for approximately 99% of phenolic compounds. The difference in phenol compounds according to the seeding dates of mung bean was not statistically significant. The total fatty acid content in beans was the highest in Pyeongchang. Significant differences in total fatty acid content were found according to the cultivation regions. Crops grown in Sohyeon and Dahyeon showed the highest soyasapogenol B content in the Suwon region, and these were the lowest in Jeonju. The total tocopherol content of beans cultivated in Dahyeon and Sohyeon was the lowest and highest in Pyeongchang. Soyasapogenol B and total tocopherol content were not significantly different according to seeding dates. This study was conducted to obtain basic data for the cultivation of mung beans with a high content of various functional materials in terms of regional specialization and optimal seeding time.

• Journal of Korean Society of Forest Science
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• v.96 no.5
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• pp.539-542
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• 2007

This study was carried out to investigate the impacts of jasmonic acid (JA) on adventitious root culture of Eleutherococcus senticosus. Adventitious root of E. senticosus were treated with jasmonic acid (JA) and cultured for 30 days. JA inhibited the root growth but increased eleutherosides accumulation, total phenolic contents and antioxidant activity. Among various concentrations of JA, 1.0 mg/L JA increased the total phenolic contents in E. senticosus adventitious root to $39.81{\mu}g/g$, about 2.6 times higher than that of the control. Consequently, high accumulation of total phenolic contents led to increase the antioxidant activity to 82.41%. The antioxidant activity of control was 37.89% at $2500{\mu}g/mL$. A linear correlation ($R^2$ = 0.9937, 0.9648 and 0.9883) was also shown between antioxidant activity (at 1250, 1875, and $2500{\mu}g/mL$) and total phenolic contents of adventitious root of E. senticosus.

• Journal of Powder Materials
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• v.26 no.6
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• pp.502-507
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• 2019

Macro-porous carbon foams are fabricated using cured spherical phenolic resin particles as a matrix and furfuryl alcohol as a binder through a simple casting molding. Different sizes of the phenolic resin particles from 100-450 ㎛ are used to control the pore size and structure. Ethylene glycol is additionally added as a pore-forming agent and oxalic acid is used as an initiator for polymerization of furfuryl alcohol. The polymerization is performed in two steps; at 80℃ and 200℃ in an ambient atmosphere. The carbonization of the cured body is performed under Nitrogen gas flow (0.8 L/min) at 800℃ for 1 h. Shrinkage rate and residual carbon content are measured by size and weight change after carbonization. The pore structures are observed by both electron and optical microscope and compared with the porosity results achieved by the Archimedes method. The porosity is similar regardless of the size of the phenolic resin particles. On the other hand, the pore size increases in proportion to the phenol resin size, which indicates that the pore structure can be controlled by changing the raw material particle size.

• Food Science and Biotechnology
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• v.14 no.6
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• pp.798-802
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• 2005

Crude extracts of thirty seaweeds collected in Korea were obtained using 50% ethanol, and total phenolic contents and antioxidant activities were compared. Two brown algae, Ecklonia cava (E. cava) and Sargassum siliquastrum (S. siliquastrum), showing high antioxidant activity based on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and superoxide anion radical scavenging activity were further investigated for their inhibitory effects on tyrosinase activity. The E. cava extract had the highest total phenolic content among the seaweeds extracts. Total phenolic contents were strongly correlated with antioxidant activity in the thirty seaweed extracts ($R^2\;=\;0.9169$). The E. cava and S. siliquastrum extracts exhibited higher inhibition to tyrosinase activity than butylated hydroxytoluene (BHT) and epigallocatechin gallate (EGCG).

• Korean Journal of Medicinal Crop Science
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• v.24 no.5
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• pp.351-359
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• 2016

Background: We investigated the optimal aqueous extraction conditions for recovery of high yields of total phenolic compounds from roots of Arctium lappa L. (burdock, Asteraceae), and we compared their antioxidant capacity. Methods and Results: The antioxidant activity of the extracts was tested using 2,2-diphenyl-1-picrylhydrazyl, 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)-diammonium salt, and oxygen radical absorbance capacity assays. In addition, the major phenolic compounds present in the extracts were determined by high performance liquid chromatography analysis. Our results suggest that the roasted burdock $100^{\circ}C$, 15 min extract exhibited the strongest radical scavenging activity and possessed the highest concentration of phenolic compounds. The polyphenol content of both dried burdock and roasted burdock significantly increased with increase in the extraction temperature and time. Conclusions: These results indicated a relationship between phenolic compound levels in burdock and their free radical scavenging activities. This suggests that phenolic compounds significantly increase the antioxidant potential of burdock extracts.

• Food Science and Biotechnology
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• v.15 no.1
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• pp.44-50
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• 2006

Contents of phenolic compounds in peel, flesh, and core of three Asian pear cultivars, Hosui, Niitaka, and Chuwhangbae, were determined at different stages of maturity. Antioxidant properties of methanol extracts of peels at various fruit maturity stages were also evaluated. Total phenolic content decreased with maturity. Arbutin, chlorogenic acid, and epicatechin were major phenolic compounds in young fruits. Catechin, 4-hydroxymethyl benzoic acid, and caffeic acid were detected in peel and core of immature and mature pears. 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activities of methanol extracts were 16.30 and $15.73\;{\mu}g$ in peel of immature Hosui and Chuwhangbae pears, respectively, and $11.59\;{\mu}g$ in mature Niitaka pears, which was significantly higher than those of other maturity stage in the same cultivar. Inhibitory activities on lipid oxidation of methanol extracts of three cultivars at all maturity stages were similar to that of ${\alpha}$-tocopherol.

• Journal of the East Asian Society of Dietary Life
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• v.14 no.5
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• pp.501-507
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• 2004

Some selected fruit juices and fermented red grape juices were investigated to determine the phenolic components by the Folin-Ciocalteu method and antioxidant capacity using α, α-diphenyl-β-picrylhydrazyl(DPPH) method. Commercial red grape beverages and red wines were also analyzed as control groups. In the juice, kiwi fruit had the highest phenolic components followed by orange(summer), red grape(Cambell Early:Yonng-Chun), mandarin orange(autumn), apple(Hong-Ok), cherry tomato, tomato and water melon. Whereas, on the antioxidant efficiency, tomato showed the highest free radical scavenging effect followed by orange(summer), cherry tomato, mandarin orange(autumn), apple(Aori) red grape(Cambell Early:Sung-Ju), kiwi fruit and water melon. The amount of pheonlic components of red wine was 2 times of that of fermented sugar added grape juice, however, the antioxidant efficiency of fermented sugar added grape juice was almost the same as that of red wine. It was found that no clear relationship could be shown between the content of phenolic component and antioxidant capacity of fruit juices and fermented red grape juices. The fruit juices from tomato, orange, cherry tomato, mandarin orange, red grape and fermented sugar added red grape juice showed high free radical scavenging effect and should be regarded as a valuable source of antioxidant.

• Korean Journal of Plant Resources
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• v.12 no.3
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• pp.215-220
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• 1999

To find out the temporal and spatial variations in contents of sugar, phenolic compounds and mineral, the sap of Acer mono MAX. were harvested from several regions and periods, and those contents were determined by solvent fractionation, TLC, HPLC and atomic absorption spectrophotometer. Most of all the free sugar contained in the sap of Acer mono MAX. was sucrose, with range of 1.35 to 3.41%. The content of total phenolic compound in the sap of Acer mono MAX. was distributed from 0.034 to 0.151 mg/100m1, and most of phenolic acid was phloroglucinol. The contents of Na, K, Ca and Mg were ranged from 24.11 to 33.15, from 13.75 to 22.10, from 47.19 to 88.00 and from 2.48 to 6.31 ppm, respectively. Contents of sugar, phenolic compounds and mineral decreased sharply at the later harvest. Comparing two different methods of the sap harvest, bore method and groove method, the contents of compounds in the study were determined higher with groove method.