• Applied Biological Chemistry
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• v.51 no.1
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• pp.11-16
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• 2008

The extraction conditions for resveratrol production from grape fruit stem, which is a by-product of grape processing, were optimized to develop high-functional grape-based products. Additionally, the bioefficacy of grape fruit stem extract (GFSE) as an antioxidant agent was evaluated. Resveratrol was extracted using various experimental conditions such as extractant type, extractant concentration, raw material-extractant ratio, extraction time and temperature, and the results were analyzed using a statistical program (SPSS). The resveratrol yield was the highest when 80% ethanol with a raw-material-extractant ratio of 1:10 (w/v) was used. In addition, the optimal temperature and time were selected as $60^{\circ}C$ and 90 min, respectively. When the antioxidant activity was analyzed and expressed as DPPH radical scavenging activity and SOD-like activity, the antioxidant activity of GFSE was higher than that of BHT, BHA and L-ascorbic acid. Finally, it was found that GFSE could be used as a raw material for the production of high antioxidant agents.

• Korean Journal of Food Science and Technology
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• v.35 no.2
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• pp.306-308
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• 2003

Contents of resveratrol in different parts of Gerbong, Campbell, and Sheridan grapes were measured through HPLC analysis. Resveratrol contents in the flesh, skin, seed, and fruit stem of each grape showed significant differences, whereas little difference was observed among the cultivars. In fruit stem, and skin and seed, resveratrol contents were 170 to 440 and 4 to $8\;{\mu}g/g-dry$ weight, respectively, an indication that the fruit stem may be a good resource for resveratrol production.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.spc1
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• pp.259-263
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• 2006

A direct HPLC method was used to analyze determination of resveratrol in grapes and wines. Content of resveratrol in different parts of 13 grape cultivars and 13 wines were quantified. The average total resveratrol content was $143.5{\mu}g/g$. Resveratrol contents in the skin, fruit, seed and fruit stem were distributed range of $0.9{\sim}104.8{\mu}g/g,\;0.1{\sim}0.5{\mu}g/g\;1.7{\sim}173.9{\mu}g/g\;2.9{\sim}247.4{\mu}g/g$, respectively. Resveratrol contents in 13 wines were distributed range of $253.3{\sim}11,271.6{\mu}g/g$.

• Korean Journal of Food Science and Technology
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• v.45 no.6
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• pp.708-713
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• 2013

The ethanol solvent extracts obtained from the pulp, skin, seeds, leaves, fruit stems, and pruning stems of four Korean new grape varieties ("Dunoori", "Narsha", "Cheongsoo", and "Heukbosek"), as well as "Campbell Early", and "Muscat Bailey A (MBA)" were evaluated for their total phenolic and anthocyanin contents. The concentrations of four phenols of biological interest, catechin, epicatechin, quercetin, and resveratrol in the different parts were quantified by high-performance liquid chromatography-ultraviolet analyses. The skin of "Narsha" and "Heukbosek", the leaves of "Narsha", the fruit stems of "MBA", and the pruning stems of "Campbell Early" and "Heukbosek" had the highest resveratrol content. In particular, the resveratrol in the fruit stems of "MBA" had the highest concentration as compared to the other varieties in the different parts. The seeds of "MBA", and the fruit stems of "MBA" and "Heukbosek" had the highest catechin content. Epicatechin was detected in the seeds, fruit stems, and pruning stems. Quercetin was detected only in the leaves. In summary, the catechin and epicatechin contents were significantly higher than the quercetin and resveratrol contents. The concentrations of the physiologically active components present in the grapes were high in the non-edible parts than in the edible parts; therefore, they could be useful in industrial applications.

• 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.

• 농업기술회보
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• v.47 no.2
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• pp.38-42
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• 2010

고추나 과수나 기본재배기술은 마찬가지이다. 그러니 고추농사 잘 짖는 이는 과수농사도 잘 지을 수 있고 과수농사 잘 잦는 이는 고추농사도 잘 지을 수 있다. 채소농사 중에 예민한 작물은 오이(메론)농사이고 과수 중에서 가장 예민한 작물은 포도이다. 그러니 재배기술 여부에 따라 품질과 수확의 폭이 클 수밖에 없다. 아울러 사과, 배, 복숭아 농사를 짓는 농가도 포도재배 시 사용하는 비료를 똑 같이 기비로 준비히십시오. 포도재배기술의 목표는 큰 송이 큰알 새까만 착색, 고당도이다. 이를 목표로 삼고 포도재배기술을 이야기 해보자. 결론부터 말하자면 UCMT농법이 가장 잘 맞는 과수가 포도이다. 포도재배에 있어서 3가지 금기사항은 '질소과다, 미숙퇴비사용, 결과과다'이며, 3가지 필수사항은 완숙퇴비(고온속성퇴비), 수분관리, UCMT농법이다.

• Korean Journal of Plant Resources
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• v.30 no.1
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• pp.96-100
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• 2017

Shoot and the fruit growth characteristics of 'Campbell Early' grape cultivar were investigated after vine thinning using the main branch leader. Before vine thinning, branch diameter was 11.8 mm, but it decreased to 9.3 mm after vine thinning. The number of shoots per vine increased to 55.9-64.5 after vine thinning. The number of fruit clusters per shoot was higher (1.5-1.75) in the vine thinning plot than in the control (0.8). Consequently, the number of clusters per vine was 98.1-106.5 in the vine thinning plot, while that in the control was 24.4-28.0. However, soluble sugar content (SSC) and tartaric acidity showed no significant differences between the control and the vine thinning plot. The proportion of >351 g fruit cluster weight after vine thinning (81.0%) was significantly higher than that of the control (32.5%). These results imply that fruit quality based on the variation in cluster weight and fruit yield was enhanced by vine thinning using the main branch leader.

• Research in Plant Disease
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• v.25 no.4
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• pp.220-225
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• 2019

During the year 2018, the symptoms of bunch rot on Shine Muscat (Vitis vinifera L.) were observed in Kimcheon-si, Gyeongbuk province in Korea. The disease appears on the Shine Muscat as a black rot due to prolific fungal sporulation after it has invaded into the Shine Muscat which look completely empty and dryness. Colonies of these fungi are present on the Shine Muscat skin from fruit setting and increase in amount from early season to harvest, while become peak at ripening stage. To isolate the causal agent, small fragments (2 to 3 mm) of decayed tissue from the lesion margin were placed onto potato dextrose agar (PDA) plates. Fungal colonies on PDA produced dense white aerial mycelium and then covered with dark black conidial heads. These heads were large and radiate, and vesicles were globose (2.12-32.0×2.0-3.1 ㎛). Based on morphological and cultural characteristics, this fungus was identified as Aspergillus tubingensis. To confirm its identity, the internal transcribed spacer, β-tubulin, and RNA polymerase II was sequenced for molecular identification. BLAST search indicated 99% identity with A. tubingensis. The pathogenicity test on healthy grape of Shine Muscat produced bunch rot, as the original symptoms. To select effective fungicides for the control of brunch rot, an in vitro antifungal activity of seven fungicides were evaluated against the growth of A. tubingensis. Five fungicides (dipenoconazole, tebuconazole, metconazole, iminoctadine, and captan) exhibited significantly strong suppression of the mycelial growth of A. tubingensis.

• The Korea Journal of Herbology
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• v.32 no.3
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• pp.71-78
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• 2017

Objectives : The various grape extracts derived from grape pulp, seed and skin, containing various types of polyphenols and flavonoids, have been known to have anti-inflammatory, antioxidant and improve cardiovascular condition as well as sun's damaging effects. However, there have been rare reports of various beneficial effects of grape fruit stem extract (GFSE), one of the waste products of grapes. We investigated anti-inflammatory and melanogenesis inhibitory effects of GFSE. Methods : One-hundred gram of grape fruit stem was extracted with 80% ethanol at room temperature for 3 days. After filtration, the ethanol was removed using vacuum evaporator, then lyophilized to obtain the dry extract which was stored at $-20^{\circ}C$ until used. NO levels were measured by using Greiss reagent. Prostaglandin $E_2$ ($PGE_2$) production was measured by ELISA assay. The expression levels of iNOS, COX-2, TRP-1 and TRP-2 were evaluated by western blot analysis. Results : GFSE reduced the level of nitric oxide and prostaglandin $E_2$ ($PGE_2$) production in a dose-dependent manner, compared to control. Expressions of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) protein were also effectively inhibited by the GFSE. In a tyrosinase inhibitory activity, GFSE significantly reduced the tyrosinase activity and melanin content in a dose dependent manner, compared to control. GFSE also decreased the expression of tyrosinase related protein-1 (TRP-1) and tyrosinase related protein-2 (TRP-2), known as a melanocyte-specific gene product involved in melanin synthesis. Conclusions : Therefore, these results indicated that GFSE had powerful anti-inflammatory and anti-melanogenic effects.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.10
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• pp.1661-1667
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• 2004

The purpose of this study was to evaluate the Quality characteristics, and was conducted to develope consumer preference of the frozen ready prepared eels by cooking method between 100 Korean (male 48, female 52) and 105 Japanese (male 43, female 62) who visited Korea. The consumers' responses about frozen ready prepared eels were measured on 9 point likert scale. In the preference test of cooking method for ready prepared eel, the Japanese and Korean preferred gas grill products in conger eel. Charcoal grill for Anguilla japonica products was estimated the most preferred cooking method by Japanese. In comparison between Japanese and Korean, Korean preferred more gas grill products than charcoal grill in Anguillajaponica products. The results for this factor were very significantly different in relation to appearance and overall acceptance of sensory characteristics (p<0.0l). The steaming products was estimated to be more delicious by Japanese than Korean. The results for this steaming products were very significantly different in evaluation of appearance, taste and overall acceptability between Japanese and Korean (p<0.05 or p<0.0l). In the domestic consumer test, the overall acceptability of eel product with ginseng and pine mushroom were 6.84 and 5.56 respectively. In the Japanese consumer test, the overall acceptability of eel product with ginseng and pine mushroom were 5.62 and 6.49 respectively. Consequently, Korea consumer preferred gas grill method for both conger eel and Anguilla japonica products added by ginseng flavor in sauce. Japanese preferred gas grill method for conger eel, charcoal grill method for Anguilla jap on ica added by pine mushroom flavor in sauce. Therefore, it is needed to study for the development of conger eel's sauce and cooking method proper to preference of Korean and Japanese in foodservice operations.