• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.6
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• pp.901-908
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• 2014

Blueberries and strawberries are highly perishable and easily contaminated with microorganisms. To maintain the quality of these commodities during refrigerated storage, the effects of two packaging materials as well as passive modified atmosphere packaging on the quality of blueberries and strawberries were investigated. The harvested blueberries and strawberries were first treated with combined non-thermal treatment of aqueous chlorine dioxide and fumaric acid, followed by packaging with polyolefin film (6,000 mL $O_2/m^2{\cdot}24hr{\cdot}atm$ at $24^{\circ}C$) and polyamide/polyamide/polyethylene film (PA/PA/PE, 60 mL $O_2/m^2{\cdot}24hr{\cdot}atm$ at $24^{\circ}C$), respectively. After combined sanitizer treatment, the populations of total aerobic bacteria in blueberries and strawberries were reduced by 2.50 and 1.97 log CFU/g while those of yeast and molds were reduced by 1.95 and 2.18 log CFU/g, respectively, compared with the control. In particular, microbial growth in these samples packed with PA/PA/PE film was reduced during refrigerated storage. In addition, the blueberries and strawberries packed with PA/PA/PE film underwent lower weight loss than those packed with polyolefin film during storage. These results suggest that appropriate packaging with proper gas permeability is necessary to maintain the quality of blueberries and strawberries during refrigerated storage.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.8
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• pp.1035-1040
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• 2012

This study was aimed to evaluate and compare the biological activities and total phenolic content of ethanol extracts of white (Superior) and colored potatoes (Red, Rose, Haryoung, Blue, Jaseo, and Jasim). Various ethanol extracts (250, 500, 1,000, and $2,000{\mu}g/mL$) were assessed for antioxidant activities of DPPH free radicals and hydroxyl radical scavenging. The cytotoxic activity of the extracts (0, 30, 60, $100{\mu}g/mL$) was also carried out by a human cancer cell lethality bioassay method. Results showed that the DPPH and hydroxyl radical scavenging activities, of all extracts increase in a concentration-dependant manner. All color-fleshed potato extracts, except for Red and Haryoung, showed higher radical scavenging activities than the general white potato extract. Cytotoxicity of the extracts as determined in THP-1 cells showed that Blue and Jasim was highly toxic at most concentrations tested. In addition, the Blue extract had the highest cytotoxic activity on $HepG_2$ cells at the concentration $100{\mu}g/mL$. The contents of total phenolic (TPC) in the extracts significantly varied from 120.0 mg/100 g powder (Superior) to 151.1 mg/100 g powder (Blue), and TPC of all color-fleshed potato extracts was higher than that of white. The greatest positive correlation was found between phenolic contents and hydroxyl radical scavenging activity (r=0.776, p<0.05), and a strong negative correlation was found between hydroxyl radical scavenging activity and cytotoxic activities on $HepG_2$ cells (r=-0.795, p<0.05). The present study demonstrates that color-fleshed potatoes have higher antioxidant and stronger anticancer activities than general potato. These results provide useful and important information for potato breeders and researchers, in order to increase the antioxidant capacity and functional value of colored potatoes for use in the food and pharmaceutical industries.

• Weed & Turfgrass Science
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• v.3 no.1
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• pp.19-28
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• 2014

Research was initiated in greenhouse to investigate effects of polymer, calcium, perlite and chitosan on the growth of Kentucky bluegrass (KB). A total of 24 treatment combinations were used in the study. Treatments were made of water-swelling polymer (WSP), calcium, perlite, and chitosan in soil organic amendment (SOA). Significant differences were observed in germination rate, turfgrass coverage, turfgrass density and top growth among treatments. Germination rate, density and plant height varied with time after seeding. A proper mix of WSP is considered to be lower than 3% for turfgrass coverage and density. Regarding survival capability and top growth, however, it was good under 6%. Overall KB growth was more influenced by calcium and perlite than chitosan. Calcium and perlite were the most effective elements for early survival capacity and turfgrass density, respectively. But no effect was found by chitosan. Top growth increased with three elements, being perlite > calcium > chitosan. The chitosan was effective in early germination, but there was no effect on top growth until 3 weeks, when compared with others. A further study is needed for investigating the effect of these materials on the growth characteristics in mixtures of sand and SOA before a field application.

• Food Science and Preservation
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• v.24 no.1
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• pp.60-67
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• 2017

In this study, we tried to establish the best method for fresh blueberry beverage production using enzyme treatment as well as low temperature extraction. During extraction of physiologically functional materials, we used low temperature to prevent nutritional loss by heat. In addition, we investigated optimal blueberry extraction conditions using various enzyme treatments (cellulase, pectinase, cellulase:pectinase (1:1) mixture) to increase extraction efficiency and reduce turbidity. A variety and ratio of enzymes, extraction temperature, extraction time, and shaking speed were considered for the best extraction efficiency rate. We observed high extraction efficiency rates of 85.72-86.55% and 87.06-87.93%, respectively, upon cellulase or pectinase treatment. In addition, a mixture of cellulase:pectinase (1:1) showed an extraction efficiency rate of 86.84-88.14%. The best extraction efficiency rate was observed when crude blueberry was treated at $45^{\circ}C$ (87.91%), for 3 h (87.88%), in a 90 rpm shaker (89.19%). Sugar content and acidity of blueberry extract were not affected by the various treatments. However, total phenolic compounds were detected upon pectinase treatment (18.62 mg/g). Only fructose and glucose as free sugars were found in all samples regardless of treatments and extraction conditions.

• Journal of Nutrition and Health
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• v.50 no.1
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• pp.1-9
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• 2017

Purpose: Fruit and vegetable juices are known to be rich sources of antioxidants, which have beneficial effects on diseases caused by oxidative stress. The purpose of this study was to directly compare the antioxidant activities of fruit and vegetable juices marketed in Korea. Methods: We analyzed four fruit juices, two vegetable juices, two yellow-green juices, and six mixed vegetable juices. Antioxidant activities were analyzed using 2,2-diphenyl-1-picrylhydrazyl (DPPH) test, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonate) (ABTS) test, and oxygen radical absorbance capacity (ORAC) assay. Protective effects against DNA damage were determined using an ex vivo comet assay with human lymphocytes. Results: DPPH radical scavenging activities were in the following order: blueberry juice > mixed vegetable C juice > kale juice > mixed vegetable P juice > grape juice. ABTS radical scavenging activities were in the following order: blueberry juice > mixed vegetable C juice > grape juice > mixed vegetable P juice > kale juice. Peroxyl radical scavenging activities as assessed by ORAC assay were in the following order: blueberry juice > kale juice > mixed vegetable C juice > grape juice. Grape or blueberry juice showed strong abilities to prevent DNA damage in lymphocytes, and the difference between them was not significant according to the GSTM1/GSTT1 genotype. Conclusion: Antioxidant activities of fruit and vegetable juices and ex vivo DNA protective activity increased in the order of blueberry juice, grape juice, and kale juice, although the rankings were slightly different. Therefore, these juices rich in polyphenols and flavonoids deserve more attention for their high antioxidant capacity.

• Korean Journal of Ichthyology
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• v.33 no.2
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• pp.84-94
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• 2021

This study was conducted to elucidate the impact of invasive species, Micropterus salmoides and Lepomis macrochirus in Geumgyeji, Samgaji and Naejangji reservoirs of National Parks, Korea in 2020. In the Geumgyeji, 1,221 individuals of 11 species in 7 families were collected including M. salmoides (relative abundance, 96.3%) and L. macrochirus (0.3%), M. salmoides fed mainly on Rhinogobius brunneus (IRI, 37.2%), Odonata (25.6%), Megaloptera (11.6%), and M. salmoides (7.0%). In the results of Samgaji showed that 854 individuals of 10 species in 5 families were collected including M. salmoides (60.8%), and M. salmoides fed mainly on Decapoda (shrimp, 33.6%), Odonata (34.4%), R. brunneus (21.2%), and Zacco platypus (6.1%). In the Naejangji showed that 1,075 individuals of 13 species belonging to 7 families were collected including L. macrochirus (38.1%) and M. salmoides (9.5%), and L. macrochirus fed mainly on Branchiopoda (77.5%), Diptera (9.8%), Decapoda (4.0%) and M. salmoides fed mainly on R. brunneus (73.3%), Decapoda (21.2%). M. salmoides of Geumgyeji and Samgaji were apparently introduced more than a 10 years ago. The fish population declined rapidly since the introduction of M. salmoides. L. macrochirus of Naejangji was introduced more than 20 years ago, which increased its relative abundance to 40%. M. salmoides was introduced five to six years ago, and the fish species and population declined rapidly since the introduction of M. salmoides. Finally, we discussed the inhabitat status and management of M. salmoides and L. macrochirus in the National Park.

• Environmental engineer
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• v.23 s.237
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• pp.2-7
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• 2006

"친환경적인 오염처리 기술과 청정생산 기술의 연구개발 등을 통해 환경과 경제가 동시에 윈윈할 수 있는 블루오션을 찾는 미래전략 수립에 더욱 노력하겠습니다." 미래지향적 사고와 탐구로 현실을 타파하고 있는 미래학자 공성진 의원(국회 환경노동위원회 소속)은 환경분야도 미래와 접목시켜야 한다고 강조한다. 공성진 의원은 17대 국회에서 초선 의원으로 활동하고 있지만 그의 경력이나 왕성한 활동은 3선 못지않은 저력을 과시하고 있다. 본지는 지난 18일 국회의원회관 공성진 의원 사무실에서 그의 환경분야 활동내용 등을 들어봤다.

• Proceedings of the Korean Information Science Society Conference
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• 2004.10c
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• pp.214-216
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• 2004

최근 3G를 지나4G를 향해 가면서 모바일 통신이 많은 발전을 이루었다. 하지만 아직까지도 모바일 장치를 사용항에 있어서 전력, 기반 속도, 이동성 등에 따라서 불편을 겪고 있는 것이 사실이다. 본 연구에서는 이러한 문제를 해결하고자 Wi-Fi와 블루투스를 함께 사용하는 모바일 회의 시스템을 구현하고 실험과 시뮬레이션을 통하여 성능 평가를 하였다. 실험을 위해 모바일 회의 시스템을 구현하였고 시뮬레이션은 NS-2를 사용하였다. 본 시스템의 구현과 실험 및 시뮬레이션 결과를 통해서 모바일 어플리케이션을 제작함에 있어서 Wi-Fi와 블루투스의 두 가지 모바일 기술을 함께 조합하여 구성하고 동시에 사용하는 방식이 효과적임을 알 수 있었다.

• Proceedings of the Korean Information Science Society Conference
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• 2001.10c
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• pp.274-276
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• 2001

블루투스와 802.11 WLAN 과 같은 기술은 ISM(Industrial, Scientific and Medical) band에서 무선 기술을 제공할 수 있어 큰 기대를 같게 하는 기술이다. 하지만 ISM band블 사용하는 이 기술들은 서로 같은 대역을 사용하기 때문에 서로 간섭을 일으키며 서로 성능 저하의 요인이 된다. 본 논문에서는 다수의 블루투스 피코넷과 802.11 WLAN환경에서의 블루투스의 성능 저하를 분석한다.

• The Science & Technology
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• v.30 no.7 s.338
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• pp.75-80
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• 1997

세계 최강의 체스기사인 게리 카스파로프가 1997년 5월 3일~11일 뉴욕에서 컴퓨터기사 딥 블루와 가진 대국에서 1승3무2패로 져서 결국 기계 앞에 무릎을 꿇고 말았다. 카스파로프를 포함한 많은 사람들이 언젠가는 컴퓨터가 인간 체스챔피언을 이길 것이나 그 시기를 2010년경 이후로 보았기 때문에 이번 딥 블루의 승리가 체스계에 준 충격이 매우 컸을 뿐 아니라 일부의 사람들에게는 기계가 인간을 지배하는 시대가 뜻밖에 일찍 다가올지 모른다는 두려움을 안겨 주기도 했다.