• Korean journal of applied entomology
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• v.59 no.4
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• pp.411-416
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• 2020

Whitefly populations found in heated tomato greenhouses were monitored across three locations in Korea (Nonsan and Buyeo, Chungnam Province; Iksan, Jeonbuk Province) from November to May during the 2015 -2018 growing seasons. From May to October, surveys were conducted in Jangsu (Jeonbuk Province), where retarding cultivation was performed. Whitefly populations were classified and quantified by location and year. The dominant species were Trialeurodes vaporariorum (Westwood) and Bemisia tabaci (Gennadius). The species populations were mixed, but the frequency of occurrece of B. tabaci was higher than that of T. vaporariorum. Although whitefly populations started to increase in late March, they sharply increased in May and the highest population density was observed at the end of the harvest season. Therefore, the management of greenhouse tomato whiteflies through monitoring should begin in early March. In the case of retarding cultivation, the management of whitefly populations should be implemented in June, before the density of whitefly populations increases.

• Journal of the Korean Wood Science and Technology
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• v.30 no.4
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• pp.51-57
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• 2002

Antimicrobial and antioxidative activites on heartwood extractives of domestic species were investigated to develop a natural fungicide or preservative. One steroid, stilbene derivatives and two flavonoids were isolated from heartwood of Robinia pseudo-acacia which has been selected due to its high antioxidative activity among the tested species. The structures were determinded as: 3-𝛽-stigmast-5-en-3-ol(daucosterol), 3,3'4,5-tetrahydroxystilbene, 3,3'4'5,7-pentahydroxyflavone(robinetin) and 3,3'4'7-tetrahydroxyflavanone(fustin) respectively on the basis of spectroscopic data and chemical correlations. According to the results of free radical scavenging activity, 3,3'4'5,7-pentahydroxyflavone was evaluated as the highest antioxidative compound among the four compounds and showed higher radical scavenging activity than those of 𝛼-tocopherol and butylated hydroxytoluene(BHT), one of the strongest synthetic antioxidants. 3,3'4'5-Tetrahydroxystilbene and 3,3'4'7-tetrahydroxyflavanone showed higher antioxidative activities than that of 𝛼-tocopherol. However, 3-𝛽-stigmast-5-en-3-ol did not show free radical scavenging activity. In this regard, it could inferred that high antioxidative activity of extractives of R. pseudo-acacia was derived from 3,3'4'5'7-pentahydroxyflavone, 3,3'4'5-tetrahydroxystilbene and 3,3'4'7-tetrahydroxyflavanone.

• Journal of Conservation Science
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• v.38 no.2
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• pp.133-143
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• 2022

In this study, we analyzed the rickshaw (Owned by the Daegu Modern History Museum) by measuring each material. The purpose of the study was to identify the materials in modern cultural assets that utilize a variety of materials in a complex way, and establish basic data for preservation and management. Using portable X-ray fluorescence analyzers (P-XRF), species identification, fiber identification, paint film analysis (microscope observation, SEM-EDS, FTIR) on metal, wood, fiber and paint was carried out. Brass, an alloy of Copper, Zinc and Iron, was measured in the metal parts. Further, wooden parts, such as Oak (Quercus acutissima), Japanese Cedar (Cryptomeria japonica), Bamboo (Bambusoideae). Torreya nucifera (Torreya spp.) were identified in the body. Fiber parts consisted mainly of cotton, but some parts were also made of leather. In terms of paint, rickshaws were applied with multiple layers, using cashew (synthetic paint used in place of lacquer). In sum, the rickshaw body part appeared to overlap with layers of fiber, metal (soild), paint, and colored (black, red) layer.

• Journal of Food Hygiene and Safety
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• v.37 no.1
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• pp.21-28
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• 2022

In this study, a new lactic acid bacterium (LAB) that could produce gamma-aminobutyric acid (GABA) was isolated from Oenanthe javanica (water celery) and identified as an Enteroccoccus casseliflavus strain. Until recently, there have been many studies on the gamma-aminobutyric acid producing lactic acid bacterium, as well as on some lactic acid bacterium in Enteroococcs genus, but none on the species E. casseliflavus. Therefore, in the purpose of finding the optimal conditions for GABA production of E. casseliflavus PL05, the effects of several conditions including the type of mediums, growth temperatures, initial pH, growth time, L-mono sodium glutamate (MSG) concentration, and carbon source were tested. The study revealed that the PL05 strain grew better in the Brain Heart Infusion (BHI) medium than in the Man, Rogosa, and Sharpe (MRS) or Tryptic Soy Broth (TSB) medium. Also, similar results were obtained with GABA production conditions. As a result of analysis on the GABA production yield by concentration of MSG, a GABA substrate, the highest production was found at 7% of MSG concentration. However, since similar level of production was found at 5%, it is considered to be more efficient to use 5% MSG concentration. The analysis on the growth and GABA production yield by carbon sources showed the highest results when maltose was used. From the final test under the optimal conditions found, 140.06±0.71 mM of GABA was produced over 24 hours with the conversion rate of 78.95%. Lastly, from the sensitivity analysis on the 10 different antibiotics, including vancomycin, it was found that there were not confirmed cases of resistance.

• Journal of Food Hygiene and Safety
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• v.37 no.4
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• pp.285-295
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• 2022

The ability of volatile components of essential oils (EO) from cinnamon, clove, and lemongrass to inhibit biofilms formed on polyethylene and stainless steel by six types of food poisoning bacteria was investigated. The main components of cinnamon EO were identified as cinnamaldehyde (38.30%), linalool (9.61%), β-caryophyllene (8.90%), and 1,3,4-eugenol (8.19%). 1,3,4-Eugenol (61.84%) was the dominant component of clove EO. The major component of lemongrass EO was citral. Citral is a natural mixture of two isomeric acyclic monoterpene aldehydes: geranial (trans-citral, 19.11%) and neral (cis-citral, 19.23%). Among these major compounds, cinnamaldehyde, linalool, eugenol, and citral exhibited comparatively strong antimicrobial activity in the disc diffusion assay. Treatments with 0.1% eugenol and citral were highly effective on biofilm inhibition on both tested surfaces. Cinnamaldehyde (0.1%) was effective against biofilm formation by Listeria monocytogenes ATCC 19112 and Staphylococcus aureus KCCM 11812. These results suggested the potential of cinnamaldehyde, eugenol, and citral treatments in inhibiting the formation of biofilms by food poisoning bacteria.

• Research in Plant Disease
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• v.28 no.4
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• pp.231-236
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• 2022

Oxypetalum coeruleum, commonly known as Tweedia, is a perennial herbaceous plant of the Apocynaceae family native to southern Brazil and Uruguay. Tweedia plants are grown as one of the most popular ornamental flowers for floral arrangement in Korea. In May 2021, several tweedia plants in a single greenhouse in Gimje, Jeollabuk-do were found to show virus-like symptoms including necrotic rings, vein-clearing, chlorotic mottle, and mosaic on the leaves, and necrosis on the stems. Here, we have identified tomato spotted wilt virus (TSWV) in symptomatic tweedia leaves by applying high-throughput RNA sequencing. In the result, a single infection by TSWV was verified without mixed infections of different virus species. To confirm the presence of TSWV, a reverse transcription polymerase chain reaction was performed with a specific primer set to the N gene of TSWV. The complete genomic sequence of L, M, and S segments of TSWV 'Oxy' isolate were determined and deposited in GenBank under accession numbers LC671525, LC671638, and LC671639, respectively. In the phylogenetic tree analysis by maximum likelihood method, 'Oxy' isolate showed a high relationship with TSWV 'Gumi' isolate from Gerbera jamesonii in Gyeongsangbuk-do, Korea; for all three RNA segments. To our knowledge, this is the first report of TSWV infection of O. coeruleum in Korea.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2020.08a
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• pp.52-52
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• 2020

유채(Brassica napus L.)는 식용유 생산을 목적으로 재배되며, 1975년에는 26.8천ha가 재배되어 연간 생산량이 34.7천톤이 생산되었으나, 외국으로부터 값싼 식용유의 대량수입으로 재배면적이 급격하게 감소되었다. 그러나 최근에 지방자치단체를 중심으로 경관용 재배면적이 증가하고 있고, 건강에 대한 관심이 높아짐에 따라 국내산 non-GM 식용유 생산을 목적으로 유채 재배면적이 급격하게 증가하고 있다. 유채의 대량생산을 위해서는 논 재배가 필수적이나 유채와 벼의 이모작 재배 시기가 겹치는 문제점이 발생하고 있어 조생종 유채의 품종개발과 함께 봄 파종이 가능한 유채의 품종 육성에 대한 요구가 매우 높다. 따라서 본 연구에서는 국내 보유 유채를 포함하는 십자화과(Cruciferae) 유전자원의 특성 평가를 통해 극조숙 유채 품종 육성을 조기에 육성하기 위해 실시하였다. 농촌진흥청 국립유전자원센터에서 분양받은 유전자원 146계통을 파종 재배하면서 핵형분석과 외부형질을 기준으로 정확한 종을 동정하였고, 각 유전자원의 생육 및 개화특성을 조사하였다. 유전자원들을 세포분석기를 이용하여 핵형을 분석한 결과, 전체 146개의 유전자원 중 유채(B. napus L.) 128계통, 갓(B. juncea Sinsk) 6계통, 배추(B. campestris Makino) 9계통, 미분류 3계통 등으로 조사되었다. 유전자원을 가을 파종(10월 22일)하였을 때 개화가 가장 빠른 계통(IT 279089)이 파종 후 137일 이후인 3월7일부터 개화가 시작되었고, 가장 늦은 계통(IT 279198)은 191일 후인 4월 30일에 개화가 시작되었다. 봄 파종(2월 4일)하였을 때 개화가 가장 빠른 계통(IT 279089)이 파종 후 79일 이후인 4월 23일부터 개화가 시작되었고 IT 279092 등 29계통은 추대와 개화가 되지 않았다. 위와 같은 연구결과를 토대로 개화시기가 빠른 유전자원을 육종을 위한 인공교배 시화분친이나 종자친으로 이용하면 지방산 품질이 좋고 극조숙성인 유채 품종의 개발이 가능할 것으로 생각된다.

• Journal of Marine Life Science
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• v.8 no.2
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• pp.93-103
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• 2023

eDNA, an abbreviation for environmental DNA, means DNA derived from organisms inhabiting in a specific environment. The utilization of eDNA extracted from environmental samples allows for efficient and accurate monitoring of organisms inhabiting the respective environment. Specifically, eDNA obtained from seawater samples can be used to analyze marine biodiversity. After collecting seawater samples and extracting eDNA, metagenome analysis enables the taxonomic and diversity analysis among marine organisms inhabiting the sampled area. This review proposed an overall process of marine biodiversity analysis by utilizing eDNA from seawater. Currently, the application of eDNA for analyzing marine biodiversity in domestic setting is not yet widespread. This review can contribute to establishment of marine eDNA research methods in Korea, providing valuable assistance in standardizing the use of eDNA in marine biodiversity studies.

• Food Science and Preservation
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• v.30 no.4
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• pp.716-728
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• 2023

The anti-adipogenic activity of Glycyrrhiza uralensis was investigated by examining the effects of its ethanol extract (GUE) on a mouse model with a high-fat diet (HFD) and 3T3-L1 preadipocytes during adipocyte differentiation. GUE administration for eight weeks significantly reduced weight gain in mice fed an HFD. GUE effectively inhibited 3T3-L1 preadipocyte differentiation and lipid droplet accumulation. This inhibitory effect is associated with the downregulation of key adipogenic regulators, including PPARγ and C/EBPα, and the modulation of adipose metabolism regulators, such as Fasn and Fabp4. LC-Q-TOF-MS analysis identified twelve phenolic and flavonoid compounds, including liquiritigenin and licorice saponin, in the GUE. These findings demonstrate that the anti-obesity effect of the GUE is attributed to the biological activity of its phenolic and flavonoid compounds. Therefore, the GUE has potential anti-obesity activity. Moreover, further studies on the isolation of bioactive components from the GUE and the investigation of the underlying molecular mechanisms of the GUE are required to establish its efficacy in metabolic disorders, including obesity.

• Weed & Turfgrass Science
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• v.2 no.1
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• pp.38-46
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• 2013

With increasing environmental issues from synthetic chemical herbicides, microbe-originated herbicides could be a fascinating alternative in current agriculture. We isolated Streptomyces strains that produced herbicidal active metabolite(s) against a grass weed Digitaria sanguinalis. According to the result from 16S rDNA sequence comparison with the close strains, the best isolate (Code name MS-80673) was identified as Streptomyces scopuliridis KR-001. The closest type strain was Streptomyces scopuliridis RB72 which was previously reported as a bacteriocin producer. The optimal culture condition of S. scopuliridis KR-001 was $28^{\circ}C$, pH 7.0 and culture period 4 to7 days. Both of soil and foliar application of the crude culture broth concentrate was effective on several troublesome or noxious weed species such as a Sciyos angulatus in a greenhouse and field condition. Phytotoxic symptoms of the culture broth concentrate of S. scopuliridis KR-001 by foliar application were wilting and burndown of leaves, and stems followed by discoloration and finally plant death. In crops such as rice, wheat, barley, hot pepper and tomato, growth inhibition was observed. These results suggest that the new S. scopuliridis KR-001 strain producing herbicidal metabolites may be a new bio-herbicide candidate and/or may provide a new lead molecule for a more efficient herbicide.