• The Plant Pathology Journal
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• v.36 no.1
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• pp.76-86
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• 2020

Cucumber mosaic virus (CMV) is damaging to the growth and quality of lettuce crops in Lanzhou, China. Recently, however, for the first time an isolate of lettuce necrotic yellows virus (LNYV) has been detected in lettuce crops in China, and there is concern that this virus may also pose a threat to lettuce production in China. Consequently, there is a need to develop a rapid and efficient detection method to accurately identify LNYV and CMV infections and help limit their spread. Reverse transcription loop-mediated isothermal amplification (RT-LAMP) assays were developed to detect the nucleoprotein (N) and coat protein (CP) genes of LNYV and CMV, respectively. RT-LAMP amplification products were visually assessed in reaction tubes separately using green fluorescence and gel electrophoresis. The assays successfully detected both viruses in infected plants without cross reactivity recorded from either CMV or LNYV or four other related plant viruses. Optimum LAMP reactions were conducted in betaine-free media with 6 mM Mg²⁺ at 65℃ for LNYV and 60℃ for 60 min for CMV, respectively. The detection limit was 3.5 pg/ml and 20 fg/ml using RT-LAMP for LNYV and CMV plasmids, respectively. Detection sensitivity for both RT-LAMP assays was greater by a factor of 100 compared to the conventional reverse transcription polymerase chain reaction assays. This rapid, specific, and sensitive technique should be more widely applied due to its low cost and minimal equipment requirements.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2022.09a
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• pp.118-118
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• 2022

Carex pumila Thunb. is a plant native to East Asia, Australia, and New Zealand. However, its effect on skin melanogenesis has not been investigated. In the present study, we evaluated its anti-melanogenic properties using B16F10 melanoma cells and zebrafish larvae in the presence or absence of α-melanocyte stimulating hormone (α-MSH). In this study we revealed that concentrations below 50 µg/mL did not induce any cytotoxicity in B16F10 melanoma cells and cardiotoxicity in zebrafish larvae. However, 50 µg/mL treatment significantly inhibited α-MSH-induced extracellular (from 181.24% α 0.62% to 105.15% α 0.31%) and intracellular melanin contents (from 119.8% α 1.2% to 53.4% α 1.7%) as well as intracellular tyrosinase activity (from 143.9% α 4.2% to 103.7% α 1.4%) in B16F10 melanoma cells. At 25 µg/mL and 50 µg/mL concentrations, it could significantly inhibit α-MSH induced hyperpigmentation in zebrafish larvae (from 100% α 2.3% to 60.7% α 1.3% and 47.5% α 1.9% respectively). Additionally, the extract suppressed α-MSH-induced cAMP-CREB-MITF signaling pathway and consequently inhibited tyrosinase expression in B16F10 melanoma cells. In conclusion, our results indicate that this plant extract could suppress the cAMP-CREB-MITF axis which consequently inhibits tyrosinase mediated melanogenesis.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1993.10a
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• pp.433-442
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• 1993

Coolstore air relative humidity (RH) is an important factor affecting the quality of horticultural products, particularly via product moisture loss. RH also has an important effect on the performance of the refrigeration evaporators and can affect the strength of paper-based packaging materials. In a large New Zealand apple coolstore, RH increased from about 75% early in season to 90% at the end, as activities in the coolstore and external conditions changed. A steady-state analysis of sensible and latent heat entry and heat removal during four typical operational periods over the season was carried out. Predicted RH was in good agreement with measured dat. For the coolstore studied, evaporator surface area and the occurrence of pre-cooling within the coolstore were the design and operational factors having greatest effect on RH. Door protection and management, and floor insulation were the next more significant factors. The method of analysis has more general application and ould be used in a variety of situations so that design for optimum RH can be performed systematically.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.3
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• pp.826-828
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• 2003

The effects of crude extract and bioactive fractions from Brachyglottis monroi on biological activity were investigated. The crude ethanol extract inhibited the growth of the Gram positive bacterium Bacillus subtilis (ATCC Strain number 19659, 1 mm zone at 150 μg/disk) and the dermatophyte Trichophyton mentagrophytes (ATCC 28185, 2 mm zone at 150 μg/disk), and toxic to P388 tumor cells (IC50 23.96 μg/ml at 75 μg/disk). Cytotoxic activity was strongly showed by Fr. 6 (P388 IC50 19.67 μg/ml at 75 μg/disk).

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.1
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• pp.250-253
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• 2004

The effects of crude extracts from medicinal plants on biological activity were investigated. The crude ethanol extract of H. paucistipula inhibited the growth of the Gram positive bacterium Bacillus subtilis ATCC 19659, (2 mm inhibition zone at 150 ㎍/disc) and the dermatophyte Trichophyton mentagrophytes ATCC 28185, (7 mm inhibition zone at 150 ㎍/disc), and toxic to P388 murine leukaemia cells ATCC CCL 46 P388D1, (IC/sub 50/ 2.48 ㎍/㎖ at 75 ㎍/disc). This crude ethanol extract of H. paucistipula is the strongest antimicrobial and cytotoxic activities against P388 murine leukaemia cells ATCC CCL 46 P388D1.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.1
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• pp.260-264
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• 2004

The effects of bioactive fractions from Brachyglottis monroi on biological activity were investigated. this bioactive subfraction 6-5 is the most cytotoxic to P388 murine leukaemia cell lines. A comparison of IC/sub 50/ values of these subfraction in cancer cell lines showed that their susceptibility to these subfractions decreased in the following order; Fr. 6-5 > Fr. 6-3 > Fr. 6-6 > Fr. 6-1 > Fr. 6-2 > Fr. 6-4 by the MTT method. Silica gel flash column chromatography concentrated the cytotoxic activity in subfraction 6-5 which eluted with 30% and 40% ethyl acetate : hexane gave a major bioactive (51 mg, P388 IC/sub 50/ 8,286 ng/mL at 7.5 ㎍/disc).

• Journal of The Korean Society of Grassland and Forage Science
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• v.17 no.4
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• pp.345-350
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• 1997

Using modified Lincoln solution, hydroponic system was developed to compare simultaneously a range of pasture species in terms of relative growth rate(RGR), rate of roots to shoots, and relative root volume and root area. Modified Lincoln solution achieved optimum growth of nineteen forage species tested, and was proved to be a good method for studying plant root characteristics. RGR was measured sucesshlly showing reasonably consistant values over time. There was a much differences in rootkhoot ratio between species within groups as between groups. Root tissue density was lower in grasses than legume or herb group. Root area index was very high for grasses and herbs, and this index should be useful for evaluating the comparative root system of different species.

• Korean Journal of Organic Agriculture
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• v.30 no.3
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• pp.423-439
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• 2022

The acute dermal and eye irritation tests of Photorhabdus temperata, a symbiotic bacterium of Heterorhabditis megidis Gwangju strain, were carried out in New Zealand white rabbit (Oryctolagus cuniculus), following the guidelines of OECD and Rural Development Administration (RDA) of Korea. In both tests, neither dermal nor eye responses were found from all the P. temperata treated rabbits and the results were classified as non-irritating. That is, erythema, eschar, edema, and any other dermal critical signs were not observed from all the experimental rabbits in the dermal irritation test. In the acute eye irritation test, no clinical signs of cornea, iritis, conjunctiva (redness, edema, lacrima, and chemosis) were observed from all the experimental rabbits. Individual ocular irritation, mean ocular irritation, and acute ocular irritation were calculated as 0.0. The results of dermal and eye irritation studies on P. temperata indicated that this bacterium could be a safe and effective alternative bionematicide against the most serious plant-parasitic root-knot nematodes in the genus Meloidogyne.

• The Korean Journal of Food And Nutrition
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• v.22 no.2
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• pp.252-260
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• 2009

According to Article 7 and Annex B of the World Trade Organization(WTO) Agreement on the Application of Sanitary and Phytosanitary(SPS) Measures, WTO members are required to notify their newly established or amended SPS measures that might affect international trade. This study analyzed SPS notifications from 1995 to 2008 to identify international trends for food safety measures. The notifications were collected from the SPS information management system and the official document distribution system of WTO. The 153 WTO members represented 37 developed countries, 84 developing countries and 32 least developed countries. The number of overall notifications was 9,820. The annual notifications increased from 198 in 1995 to 1,264 in 2008. The monthly average notifications were from 44.8 in December to 69.5 in June; however, there were no statistical differences among them. The six leading Members in terms of notification submissions were United States(U.S.), Brazil, New Zealand, Canada, European Community and Korea. Among the regular and emergency notifications, 62.7% notifications were concerned with food safety, followed by animal and plant protections. Among animal protection notifications, 54.8% were emergency situations. Of the 4,821 food safety notifications, 60.4% were from developed countries, and 39.3% were from developing countries. Measures concerning pesticide residues and risk assessments were mainly from developed countries. In contrast, 77.5% of the measures concerning zoonoses were from developing countries. However considering the numbers of developing and developed countries, the average number of measures for each country was similar. Food safety measures were mainly involved pesticide residues followed by food additives, zoonoses, new regulations, labeling. As the overall notifications, zoonosis measures were mainly emergency notifications. Measures concerning pesticide residues, food additives, zoonoses, new regulations, veterinary drugs, and labeling were submitted most often by the U.S., Korea, Albania, U.S., Australia, and U.S., respectively. Identifying the exact trends of food safety measures was complicated by a number of factors. However, WTO notifications might be useful tool in providing a general view of international trends.

• The Plant Pathology Journal
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• v.25 no.2
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• pp.121-127
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• 2009

Since July 2005, survey of chestnut ink disease was carried out in chestnut stands located at southern parts of Korea. Dead chestnut trees showing inky ooze on necrotic trunks were found in two different locations. In order to isolate and identify the causal fungus, infected tissues and soil samples around dead or dying trees were collected and placed on Phytophthora-selective medium. Rhododendron and chestnut tree leaves were used as a bait to isolate the fungus from soil samples by attracting zoospores in soil suspensions. On V-8 culture medium, the isolates produced homothallic oogonia with protuberances ($34.0-46.2{\times}21.9-26.7{\mu}m$) abundantly, but did not produced sporangia. Mass production of sporangia was possible by immersing agar plugs with actively growing mycelium in the creek water at $18^{\circ}C$ for 3 days. Sporangia were papillate, and ovoid to obpyriform ($17.0-38.9{\times}14.6-29.2{\mu}m$) in shape. Comparison of the ITS sequences revealed that the isolates had 100% identity to the P. katsurae isolates from Japan and New Zealand and 99.6% identity to other P. katsurae isolates. All of the examined isolates from Korea were completely identical to each other in ITS sequence. Numerous sporangia were formed in filtered as well as unfiltered creek water, but no sporangia formed in sterilized distilled water. Light induced sporangia formation, but has no influence on oospore formation. Amendments of ${\beta}$-sitosterol in culture media have no significant effect on mycelial growth but significantly stimulate oospore and sporangia formation.