• The Korean Journal of Food And Nutrition
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• v.19 no.3
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• pp.311-317
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• 2006

Physicochemical analysis of the wild grape juice and its wine extracted with ethanol were assessed. The contents of moisture in wild grape juice and its wine were 78.7${\pm}$0.2% and 74.4${\pm}$O.4%, respectively. Total anthocyanin and flavonoid contents of wild grape juice were higher 4 times and 10 times than those of wild grape wine, respectively. Of the 17 amino acids, the glutamic acid in wild gape juice and threonine in wild grape wine were the highest, which were 43.7${\pm}$1.4mg/100 g and 14.1${\pm}$0.7 mg/100 g, respectively. Electron donating abilities of wild grape juice and its wine at concentration of 1,000 ${\mu}$g/ml were 93.1${\pm}$1.2% and 88.9${\pm}$O.8%, respectively. The nitrite scavenging abilities of wild grape juice and its wine were gradually increased by increasing levels of the extracts to 79.6${\pm}$1.27% and 72.8${\pm}$1.01% at concentration of 1,000 ${\mu}$g/ml under pH 2.5.

• Korean Journal of Food Science and Technology
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• v.35 no.1
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• pp.121-124
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• 2003

Optimal extraction condition and free radical scavenging effect of ethanol extracts of Olympia grape (Vitis labruscana L.) seeds and skins were determined. Extraction yield of grape seeds increased with increasing extraction temperature increased, but was not affected by ethanol concentration in grape skins. Highest extraction yields obtained with 100% ethanol concentration at $78^{\circ}C$ were 36 and 49.5% in seeds and skins, respectively. Ethanol extract of grape seeds obtained at $78^{\circ}C$ showed stronger $RC_{50}\;(409.7\;{\mu}g/mL)$ than that of grape skins. Among organic solvent fractions, ethylacetate fraction obtained from ethanol extract of grape seed showed the strongest $RC_{50}\;(136.7\;{\mu}g/mL)$. Overall, ethanol extracts of grape seeds and their organic fractions showed significantly stronger free radical scavenging effect than those of skin extracts.

• Food Science and Preservation
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• v.11 no.4
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• pp.455-460
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• 2004

This study was conducted to determine the yield, free radical scavengering effect and total phenol contents of various solvent fractions on the crude and defatted grape seed extract during storage. The optimal condition for the extraction yield, free radical scavengering effect and total phenol contents was $90\%$ ethanol for 6 hour at $70^{\circ}C$. The extraction yield for crude and defatted grape seed at optimal condition was $8.9\%\;and\;9.16\%$, respectively. Also, the strongest free radical scavengering effect with $41.52\;{\mu}g/mL$ was observed in $95\%$ ethanol of defatted grape seed extracted for 6 hour at $70^{\circ}C$. Similar result was observed in total phenol contents of defatted grape seed. The ethyl acetate fraction obtained from ethanol extract of defatted grape seed showed the strongest RC50($12.35\;{\mu}g/mL$) compared to other organic fractions. Free radical scavengering effect of crude and defatted grape seed extracts treated with alkali condition(pH 10) was reduced compared to that of acidic condition(pH 2) during storage far 1 month at $50^{\circ}C$. Overall, more stronger free radical scavengering effect and higher total phenol contents in defatted grape seed extracts was observed than that of crude grape seed.

• Korean Journal of Agricultural Science
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• v.39 no.3
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• pp.371-376
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• 2012

This study was conducted to investigate the effect of dietary supplementation of wild grape (Vitis coignetiae) on egg qualities. Laying hens were randomly assigned to three different dietary groups containing 0, 0.25, and 0.5% of wild grape and fed for 8 weeks, respectively. Eggs were collected after feeding period and stored at $4^{\circ}C$ for 7 days. Egg quality traits and cholesterol level of egg yolk were measured at 0 and 7 days of storage. There were no significant differences in total cholesterol content of egg yolk and egg shell thickness among the treatments. However, egg weights of wild grape-fed groups significantly increased compared to that of control. Dietary supplementation of 0.25% wild grape increased the shell and yolk colors compared to the control. Dietary supplementation of 0.5% wild grape significantly increased albumen height and Haugh unit and decreased egg shell hardness and pH values at day 0. However, no differences were found after 7 days of storage. Consequently, the dietary supplementation of wild grape improved the egg qualities on some extent including egg weights, shell and yolk color, albumen height, and Haugh unit.

• Journal of Plant Biotechnology
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• v.42 no.4
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• pp.298-311
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• 2015

Grape is one of the important fruit crops around the world, and exposed to disease and pests, and internal or environmental stresses in the vineyards. Breeding and cultivation of new varieties of high quality-grapes resistant to diseases and pests and tolerant to stresses are the most important steps in the grape production. However, conventional breeding has laborious and time-consuming procedures in maintaining and selecting seedlings in the fields. Development of molecular breeding technology through understanding of molecular mechanism of useful traits can be used as an alternative strategy to improve the efficiency of grape breeding program by cross hybridization in grape development programs. The completion of the grape genome sequencing project provided the way to discover the novel genes and to analyze their functions. Comparative genomics, transcriptomic analysis, and the genome-wide identification and analysis of useful genes as well as development of molecular marker for valuable traits could provide novel insights into fruit quality and the responses to diseases and stresses, and can be used as important information in molecular breeding programs for grape development.

• KSBB Journal
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• v.22 no.5
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• pp.351-355
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• 2007

Resveratrol, a polyphenolic compound with antioxidative property, was purified from the grape's twig to be used as functional additives of food and/or cosmetics. Extraction of the grape's twig was performed using 80% ethanol in ultrasonic extractor for 60 min. The crude extract was purified up to 99% after elution through silica gel open column chromatography. The stability of the purified resveratrol was as follows: a half life of 90 days at 40$^{\circ}C$ and 60 days at 25$^{\circ}C$. A sensory test of the commercial grape juice including the 1-10 ppm of purified resveratrol showed better preference than the grape juice without purified resveratrol additive. Color and smell test showed no difference between the samples. The grape twig can be used as a valuable resource for the extraction of resveratrol, which would be added to nutraceutical and cosmetic products.

• The Plant Pathology Journal
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• v.24 no.3
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• pp.269-278
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• 2008

Ripe rot was frequently observed on fruits, leaves and stems of grape growing in eight locations in Korea from 2004 to 2006. All 30 isolates of Colletotrichum sp. were obtained from lesions of the ripe rot on grape plants. Out of the isolates, 19 isolates were identified as Colletotrichum acutatum and the others as Colletotrichum gloeosporioides based on morphological and cultural characteristics. Inter and intra specific variations of the Colletotrichum spp. isolates were investigated using RAPD and sequences of rDNA ITS and $\beta$-tubulin-2. Isolates of C. acutatum and C. gloeosporioides were distinctly differentiated by molecular analyses. Phylogenetic trees of ITS and$\beta$-tubulin-2 showed that Korean isolates of C. acutatum were clustered into groups A2 and A3 among the eight global groups. A2 included non-chromogenic isolates and A3 chromogenic ones. Both C. acutatum and C. gloeosporioides isolates were tested for pathogenicity to grape leaves. All isolates tested induced lesions on the leaves of grape by artificial inoculation. There was no difference in pathogenicity between C. acutatum and C. gloeosporioides isolates. This is the first report that C. acutatum except C. gloeosporioides causes grape ripe rot in Korea.

• The Korean Journal of Food And Nutrition
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• v.10 no.2
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• pp.174-179
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• 1997

The antimicrobial and GTase(Glucosyltransferase) inhibition activity were investigated for solvent fractions of Gall-nut, variety of fork drugs and Red-grape husk water extracts. Among them, Gall-nut and Red-grape husk water extracts were selected for the powerful antimicrobial and GTase inhibition activity. The methanol fractions of Gall-nut and Red-grape husk were showed very powerful antimicrobial activity on both B. subtilis and E. coli. The MIC(Minimum Inhibitory Concentration) of gall-nut methanol fraction were 1.0mg/ml for B. subtilis and 3.0mg/ml for E. coli. Red-grape husk were 2.0mg/ml for B. subtilis and 3.0mg/ml for E. coli. The methanol fractions of Gall-nut and Red-grape husk were showed very powerful Gtase inhibition activity. The concentrations of these fractions for 80% inhibition of GTase activity were 1.08$\times$10-3mg/ml and 1.08$\times$10-2mg/ml, respectively. The principal compound for the antimicrobial and GTase inhibition activity in tese extracts seems to be polyphenol derivatives.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.1
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• pp.109-114
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• 2003

Antimicrobial activities of grape seed ethanol extract and its serial solvent fractions were investigated against various food poisoning microorganisms. The grape seed ethanol extract showed dose dependant antimicrobial activity against Bacillus subtilis ATCC 9372 or Staphylococcus aureus ATCC 6538, whereas had limited effect on Pseudomonas aeruginosa IFO 3080, Salmonella enteritidis IFO 3313 and Escherichia coli ATCC 25922. Ethylacetate and butanol fractions ameng the serial solvent fractions of grape seed ethanol extract contained the catechin at the levels of 35.7 mg/g and 20.2 mg/g, respectively. Nevertheless, the butanol fraction of grape seed ethanol extract showed intense antimicrobial activity compared with the ethylacetate fraction on all microorganisms tested. It was found that the butanol fraction was mainly composed of oligomeric or polymeric polyphenols such as condensed tannins by the fractionation on C l8 cartridge according to the difference in the degree of polymerization. Therefore, it seems that the antimicrobial activity of grape seed ethanol extract is related to the degree of polymerization of proanthocyanidin as well as the total content of flavan-3-ol composing the proanthocyanidin.

• Korean Journal of Agricultural Science
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• v.47 no.3
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• pp.533-544
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• 2020

In this paper, we conducted a dynamic ex-post assessment on the grape business cessation support System. Based on the analysis results, in the short term, there was an increase in grape price due to a decrease in production and accompanying increases in the prices of consumption substitution items. However, in the long run, grape prices fell again due to an increase in grape production because of the entry of new grape farmers and the growth of adult grape trees. In addition, the analysis showed that the balloon effect caused by the conversion of crops caused indirect damage such as an increase in the production volume of substitution crops and a decrease in prices. When analyzing the social welfare measurement, the results showed that the support system for business cessation increased the overall social welfare due to an increase in producer welfare because of a price increase in the short term, but in the long term, both producer and consumer welfare decreased. In the end, it is necessary to review the system because the government's intervention may cause market distortion and inefficient resource allocation. Above all, it is necessary to minimize the indirect effect of the industry's contraction and balloon effect due to excessive business cessation. For this, conditional support should be provided in parallel with post management rather than unconditional support. In addition, it is necessary to provide a strategic support system that considers substitution items in addition to those items to be supported.