• Korean Journal of Pharmacognosy
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• v.44 no.3
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• pp.220-223
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• 2013

In the course of screening tyrosinase inhibitory activity, total methanolic extract and EtOAc-soluble fraction of Smilax china leaves showed significant inhibitory activity. Further fractionation and isolation of the EtOAc-soluble fraction resulted in 12 phenolic compounds, which were identified as 4-hydroxybenzoic acid (1), 3,4-dihydroxybenzaldehyde (2), 3,4-dihydroxybenzoic acid (3), 3,4-dihydroxyacetophenone (4), 3-hydroxy-4-methoxy benzoic acid (5), trans-p-hydroxycinnamic acid (6), cis-p-hydroxycinnamic acid (7), trans-resveratrol (8), cis-resveratrol (9), dihydroresveratrol (10), moracin M (11) and kaempferol (12). Compounds 1-11 were first reported from this plant. Among the isolated compounds, compounds 2, 8, 9 and 12 showed strong inhibition on tyrosinase activity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.2
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• pp.192-198
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• 2006

Treatment effects of grape fruit stem extracts (GFSE) containing trans-resveratrol on the storage property of fresh jujube (Zizyphus jujube) were investigated. Fresh jujubes were packed in different storage containers [polyethylene terephthalate (PET) and polyethylene (PE)], and treated with GFSE containing trans-resveratrol of 10, 30 and 50 ppm, respectively. The storage vessels filled with $N_2$ gas, and stored in refrigerator $(0{\pm}1^{\circ}C)$ during 18 weeks, and then quality characteristics during storage period were analysed. Ethylene gas increased until 8 weeks and decreased afterward. Decaying of jujube started at $6\~8$ weeks in control, but it did at 14 week storage for the fruits at $50\%$ maturity treated with 10 ppm of GFSE and packed in PE vessel. Soluble solid (Brix degree) and total acidity of fresh jujube slightly increased in all the treatments during storage period. Hardness slightly increased until 4 weeks and decreased afterward. Vitamin C content was at the highest content of $86.8\~273.4$ mg/100g for most of treatments at 2 weeks and decreased afterward. Storage stability was higher for $50\%$ maturity fruits than for the $70\%$ maturity, and higher for PE vessels than PET containers. Storage period of fresh jujube in this experiment ranges in $10\~12$ weeks for $50\%$ maturity fruits treated with 10 ppm of GFSE and packed in PE vessel.

• Food Science and Preservation
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• v.21 no.6
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• pp.790-798
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• 2014

The nutritional compositions and antioxidative activities of the Kimcheon lowbush and Pyungtaek highbush blueberries cultivated in South Korea were investigated. The approximate compositions, pH, and soluble-solid and mineral contents of P, Ca, Mg, Na, and Zn were determined. Both blueberry cultivars had mainly fructose and glucose as free sugars while disaccharides such as sucrose, maltose, and lactose were not detected in both. Oleic, linoleic, and linolenic fatty acids were the major fatty acids in both types of blueberries. The total of 16 free amino acids, including seven essential and nine non-essential amino acids, were higher in the Pyungtaek highbush blueberry. Among the amino acids, arginine was especially much higher in the Pyungtaek highbush blueberry. The anthocyanin, resveratrol, and polyphenol compounds, which are the important biologically active compounds in blueberries, were found. The anthocyanin contents of the Kimcheon lowbush and Pyungtaek highbush blueberries were 22.0 and 18.1 mg/100 g, respectively; the resveratrol contents by HPLC, 0.12 and 0.11 mg/100 g; and the total polyphenol contents, 141.3 and 138.4 mg/100 g. The electron-donating ability determined based on the DPPH radical scavenging activity was increased in a concentration-dependent manner, and it was higher than that of the Pyungtaek highbush blueberries, which implies that it is highly correlated with the higher amounts of total polyphenol, anthocyanin, and resveratrol in it. In conclusion, the two varieties of Korean blueberries can be suggested as potential sources of high-value-added functional foods.

• Journal of the Korean Wood Science and Technology
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• v.28 no.3
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• pp.70-77
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• 2000

Among four compounds such as oxyresveratrol, resveratrol, morin and afzelechin isolated from the heartwood of Morns bombycis, oxyresveratrol and resveratrol which belong to stilbenoid indicated high antioxidative and antimicrobial activity, respectively. Based on this result, this experiment was carried out to elucidate the relationship between biological activities of stilbenoids and their chemical structures using two isolated and six synthesized ones prepared by Wittig reaction. Antimicrobial activity of 3,5-dihydroxystilbene(pinosylvin) devoid of hydroxyl group of B-ring was the best among the tested stilbenoids. Antimicrobial activities of the stilbenoids showed negative dependency on the number of hydroxyl groups of B-ring, that is, the fewer number of hydroxyl groups of B-ring, the higher antimicrobial activity. On the other hand, antioxidative activities of the stilbenoids indicated a positive relationship with the number of hydroxyl groups of B-ring. In tetrahydroxystilbenoids, antioxidative activities of the compounds possessing ortho-diphenol structure, 2',3,3',5- and 3,3',4',5-tetrahydroxystilbene, were superior to the others. As a result, it was concluded that resveratrol and oxyresveratrol isolated from the heartwood of M. bombycis had antimicrobial and high antioxidative activities, and these activities of stilbenoids were also dependent on the number and position of hydroxyl groups of B-ring.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.56 no.4
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• pp.394-399
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• 2011

This experiment was conducted to select suitable cultivars and evaluate growth characteristics to get basic information for sprouting peanut. On sprouting peanut, it showed a rapid increase in trans-resveratrol content that has effects on anti-cancer, anti-inflammatory, blood-sugar-lowering and other beneficial cardiovascular in mouse. For this experiment, characteristics of peanut sprouts were tested in 37 cultivars grown for 7 days at $26^{\circ}C$ temperature. There were a lots of variations in the growth characteristics among cultivars as followers : The range of 100 grain weight was 56 to 142 g, hypocotyl length was 4.3 cm to 5.8 cm, diameter of hypocotyl was 5.0 to 8.0 mm, epicotyl length was 0.8 cm to 4.6 cm, seedling ratio per seed number was 84% to 100%, weight per seedling was 4.9 g to 8.4 g, the rate of hypocotyl cleavage was 0% to 46%, the content of trans-resveratrol was $22.5\;{\mu}g/g$ to $88.2\;{\mu}g/g$ and sprout yield was 360% to 820%. The selection points considered were high sprout yield, high seedling rate, high resveratrol content, low brownish cotyledon, no hypocotyl cleavage, and fat hypocotyl etc. The best cultivar selected was 'Jokwang' that showed 7.8 mm diameter, clean cotyledon color, 100% seedling rate, 0% hypocotyl cleavage, $63.3\;{\mu}g/g$ resveratrol, and 820% sprouting yield. This cultivar was expected to be of use as a new food and nutraceutical material. Relationship between growth characteristics showed that root length had significant positive correlations with epicotyl length, resveratrol content and sprouting yield but negative correlations with hypocotyl diameter and cleavage. Hundred grain weight showed negative correlations with resveratrol content, seedling rate and sprouting yield but positively correlated with curved hypocotyl rate and hypocotyl cleavage positively. This result showed small grain seed will be more appropriate for sprouting peanut.

• Horticultural Science & Technology
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• v.30 no.3
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• pp.301-307
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• 2012

To develop high value added healthy functional resource from Korean mulberry, the bioactive compounds and antioxidant activities of three different mulberry cultivars were investigated and compared with blueberry and strawberry. Total phenolics, total flavonoids, and trans-resveratrol of 'Daesungppong' were the highest than the 'Suwonppong', whereas those of the strawberries were the lowest. In case of total anthocyanins, 'Daesungppong' was also the highest and followed by blueberry. The antioxidant activities of 'Daesungppong' using DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS (2,2'-azinobis-(3-ethylbenzothiazoline-6-sulphonic acid), and FRAP (Ferric reducing antioxidant power) assays were the highest followed by 'Suwonppong'. Meanwhile, there were no significant differences in the antioxidant activities between 'Cheongilppong' and blueberry, and the activities of strawberry were the lowest. Furthermore, there was a strong correlation (r = 0.764-0.897) between DPPH, ABTS, and FRAP assays with the bioactive compounds such as total phenolics, total flavonoids, and total anthocyanins. Therefore, Korean mulberry, especially 'Daesungppong' demonstrated interesting biological properties that suggest its use as a potential source and high value added of natural antioxidant compounds and antioxidant activity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.4
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• pp.567-571
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• 2005

In this study, the effects of varying the amount of water, soaking time at $25^{\circ}C$ and drying time after soaking at $45^{\circ}C$ on the induction of resveratrol were evaluated to optimize the soaking treatment by response surface methodology (RSM). After response surface regression (RSREG), the second-order polynomial equation was fitted to the experimental data. The analysis of variance showed that the model appeared to be adequate $(R^2=0.9547)$ with no significant lack of fit (p>0.1). From statistical analysis, amount of water and soaking time were found to be significant factors. On the other hand, drying time was not significant. Ridge analysis showed that the optimized parameters were $67.15\%$ for amount of water, 19.58 hr for soaking time, 65.56 hr for drying time. It was confirmed that resveratrol content was increased from $0.1\;{\mu}g/g$ to $4.55\;{\mu}g/g$ under the optimized conditions. In addition, the experimental values at the optimized condition agreed with values predicted by ridge analysis. The analytical method validation parameters such as accuracy, precision, and specificity were calculated to ensure the method's validity.

• Proceedings of the Korean Society of Crop Science Conference
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• 2003.10a
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• pp.254-255
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• 2003

• Journal of the Korean Wood Science and Technology
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• v.37 no.5
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• pp.474-479
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• 2009

Pinus koraiensis inner bark was collected and extracted with 95% ethanol. The extracts were concentrated and then sequentially fractionated using n-hexane, $CH_2Cl_2$, EtOAc, and $H_2O$ to be freeze dried. A portion of EtOAc fraction (6.6 g) was chromatographed on a Sephadex LH-20 column using aqueous methanol to isolate (+)-catechin (1), (-)-epicatechin (2), and trans-pinostilbenoside (3). Resveratrol (4) and trans-pinostilbene (5) were isolated by column chromatography using EtOH-hexane mixture after purification with aqueous methanol. The structures of these stilbenosides and flavans were characterized by spectroscopic tools using NMR and MS.

• Journal of Food Hygiene and Safety
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• v.24 no.3
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• pp.194-199
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• 2009

The effects of part of plum, alcohol content and addition of t-resveratrol on the formation of ethyl carbamate during the fermentation for wine were investigated at a time interval (45 days) for 6 months. The concentration of the ethyl carbamate in plum wine was determined according to KFDA guideline for ethyl carbamate analysis. In the plum wine with 16% or 30% alcohol content, the concentrations of ethyl carbamate were increased with time of fermentation periods. The maximum concentrations of ethyl carbamate in 16% and 30% plum wines after the fermentation for 6 months were $0.071{\mu}g$/g and $0.188{\mu}g$/g, respectively. When t-resveratrol was added at the level of $10{\mu}g$/g in both 16% and 30% plum wine, the concentrations of ethyl carbamate at 6 months were 0.078 and $0.216{\mu}g$/g, respectively. The addition of t-resveratrol at the level of $300{\mu}g$/g in both 16% or 30% plum wine, the concentrations of ethyl carbamate at 6 months were 0.078 and $0.169{\mu}g$/g, respectively. The ethyl carbamate in the plum wine was not formed during fermentation for 6 month as using the flesh of plum, but $0.588{\mu}g$/g of ethyl carbamate was formed as using plum with plum seed. The addition of $300{\mu}g$/g of t-resveratrol actually increased the concentration of the ethyl carbamate by $0.088{\mu}g$/g as fermented for 6 months using plum with seed. These results suggest that the flesh of plum should be used to reduce the formation of ethylcarbamate for production of plum wine and that the addition of t-resveratrol during fermentation of plum wine can not reduce the concentration of the ethyl carbamate.