• 한국응용곤충학회지
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• 제38권2호
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• pp.123-128
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• 1999

최근 곤충병원성 선충은 생물학적 살충제로서 크게 주목을 받고 있다. 이러한 곤충병원성 선충의 in vitro배양, 저장, 수송 과정에서는 낮은 용해도와 물질전달 문제 때문에 적절한 산소 공급이 매우 중요하다. 4종의 서로 다른 Steinernema 곤충병원선충에 대하여 5L 생물반응기를 이용하여 온도를 변화시키면서 산소요구도(OUR)들을 측정하였다. 13~17$^{\circ}C$범위에서는 모든 Steinernema종의 산소 요구도는 0.5$\times$${10}^{-3}$ mmolO$_2$/L.min 이하였다. S. glaseri Dongrae와 S. carpocapsae Pocheon의 경우 산소요구도(mmolO$_2$/L.min)는 21$^{\circ}C$에서는 각각 0.4$\times$${10}^{-2}$와 0.75$\times$${10}^{-2}$, $25^{\circ}C$에서는 $1.5\times$${10}^{-2}$와 3.2$\times$${10}^{-2}$, 29$^{\circ}C$에서는 2.8$\times$${10}^{-2}$와 5.8$\times$${10}^{-2}$였다. 그러나 50~150rpm의 교반속도에서는 산소 요구도의 변화가 그다지 크지 않았다. S. glaseri NC, S. glaseri Dongrae, S. glaseri Mungyeong 그리고 S. carpocapsae Pocheon종의 비산소 요구도(${qo}_{2}$)는 $25^{\circ}C$에서 각각 0.3$\times$${10}^{-8}$, 0.5$\times$${10}^{-9}$, 0.3$\times$${10}^{-9}$, 그리고 0.2$\times$${10}^{-9}$mmolO$_2$/cell.min였다. 곤충병원성 선충의 크기와 온도가 증가됨에 따라 ${qo}_{2}$ 또한 증가하였다.

• The Plant Pathology Journal
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• 제20권1호
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• pp.63-66
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• 2004

Ginseng (Panax ginseng) is one of the most widely cultivated medicinal herbs in Korea. However, yield losses reached up to 30-60％ due to various diseases during 3 or 5 years of ginseng cultivation in the country. Therefore, successful production of ginseng roots depends primarily on the control of diseases. The objective of this study was to select potential biocontrol agents from rhizobacteria isolated from various plant internal root tissues for the control of multiple ginseng diseases as an alternative to fungicides. Among 106 Bacillus strains, two promising biocontrol agents, Bacillus pumilus strain B1141 and Paenibacillus lentimobus strain B1146, were selected by screening against root rot of ginseng caused by Cylindrocarpon destructans in a greenhouse. Pre-inoculation of selected isolates to seed or l-year-old root of ginseng resulted in stimulation of shoot and/or root growth of seedlings, and successfully controlled root rot caused by C. destructans (P<0.05). Furthermore, drenching of cell suspension of the selected isolates on seedling-growing pots reduced the incidence of Phytophthora blight after the seedlings were challenged with zoospores of Phytophthora cactorum (P<0.05). P. lentimorbus strain B1146 showed antifungal activity against various soil-borne pathogens in vitro, while B. pumilus strain B1141 did not show any. Results of this study suggest that some rhizobacteria can induce resistance against various plant diseases on ginseng.

• 농업과학연구
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• 제44권3호
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• pp.339-347
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• 2017

Sclerotium rolfsii causing southern blight on numerous vegetable and fruit crops was isolated from stems of chili peppers showing wilting symptoms. The pathogen was identified by morphological observation and DNA sequencing analysis of ITS region. To select an effective fungicide for control of southern blight, we investigated the inhibition efficacy of thirty fungicides included in nine groups of fungicides with different mechanisms of action. A fungal growth inhibition assay was conducted through an agar dilution method by using mycelial discs and sclerotia of the pathogen as inoculum, respectively. When mycelial discs were used as an inoculum, several fungicides showed good inhibitory activity against the mycelial growth of S. rolfsii 12-6. All DMI fungicides tested had a good inhibition except for prochloraz which had low inhibitory effect. All strobilurin fungicides tested except for kresoxim-methyl and all SDHI fungicides tested except for boscalid and fluopyram, had a good inhibition. Also, fludioxonil, a protective fungicide and fluazinam had a good inhibitory effect. Interestingly, when sclerotia were used as an inoculum, inhibition efficacy was increased for fluopyram, a SDHI fungicide, and for some protective fungicides such as propineb, chlorothalonil, dithianon, and folpet. All the fungicides selected in this study should be tested in the field for their control activities against stem rot for practical use in chili pepper cultivation.

• 한국어병학회지
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• 제18권1호
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• pp.19-28
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• 2005

2003년 북제주 지역의 육상양식장에서 양식중인 넙치에서 새로운 타입의 스쿠티카섬모충을 분리하였다. 이 충은 환경에 따라 ciliate와 cyst로 변태하며 장기간 생존하였는데, ciliate stage의 크기는 영양상태가 양호한 시기 기준 평균 길이 41.8, 폭 21.0 ${\mu}m$ 이었으며, cyst stage는 평균 길이 17.0 ${\mu}m$, 폭 13.5 ${\mu}m$ 이었다. 변태하는 주 원인은 먹이 양이었다. 먹이가 부족하면 cyst로 변태하여 장기간 생존이 가능하며, 먹이가 풍부해지면 ciliate로 재변태하여 활발히 증식하였다. In vitro 배양시험 결과 MS BHI 배지에서 비브리오균 (V. lentus)을 먹이로 하여 15$^{\circ}C$에서 최고 2.9${\times}$105 ${m\ell}^{-1}$의 고밀도로 배양되었다. 환경에 대한 적응시험 결과 ciliate는 염분농도 1-55 ppt, 온도 2.5-30$^{\circ}C$, pH 6-9 범위에서 증식이 가능하였다. 특히 0$^{\circ}C$에서도 7일 이상 장시간 생존이 가능하여 환경에 대한 적응력이 매우 뛰어났다. cyst는 먹이가 없는 상태에서 장시간 생존이 가능하였는데, 5$^{\circ}C$에서는 320일 동안 생존하였으며 온도가 높아질수록 생존기간은 짧아졌다. 화합물을 이용한 in vitro 구제시험에서는 포르말린과 과산화수소 모두 200 ppm/1시간 약욕으로 구제효과가 있었으나 화합물의 약욕농도와 시간에 따라 효과가 달랐다.

• 원예과학기술지
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• 제33권6호
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• pp.877-882
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• 2015

본 실험은 생물반응기를 이용한 딸기 조직배양묘의 대량증식 시 순화 생존율 향상을 위하여 polyethylene glycol(PEG 6000)을 농도별, 처리시기별로 실험하였고 기내생육조사는 배양 6주 후에 실시하였다. 모든 PEG처리구의 생장량은 대조구에 비해 매우 감소하였고, 농도가 높아질수록 생장억제 효과가 급격히 나타났다. PEG $5g{\cdot}L^{-1}$처리 시 초장은 대조구의 7.9cm보다 매우 짧아졌고, 특히 생체중은 1.60g으로 대조구보다 감소하였다. PEG $5g{\cdot}L^{-1}$의 배양1주차에서 4주차까지의 처리시 초장이 3.0-3.9cm 범위로 대조구보다 매우 짧았으나, 배양5주차 처리의 초장은 5.3cm로 큰 차이를 보이지 않았다. PEG $5g{\cdot}L^{-1}$의 처리시기별 순화 생존율은 대조구에 비해 배양4주 처리에 5.4%, 배양5주차 처리에 8.7% 향상되었다. 따라서 생물반응기를 통해 대량증식된 딸기 조직배양묘의 순화율 향상을 위해 PEG는 $5g{\cdot}L^{-1}$의 농도로 배양 5주차에 처리하는 것이 적당하였다.

• 한국버섯학회지
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• 제16권2호
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• pp.61-64
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• 2018

This study was carried out to investigate the management characteristics and growth performance of L. edodes from the cooling stage to incubation. Bags of different heights and weights are available for bagging. When the medium size of $17{\times}13cm$ was used and the size of the inoculation hole was changed from 1/3 to 2/3, the browning period was shortened to 30 days. Mycelial growth was evaluated according to the cooling temperature after sterilization. It was observed to be the highest at 122 mm/15 days at $10^{\circ}C$ and 114 mm/15 days and 117 mm/15 days at $15^{\circ}C$ and $20^{\circ}C$, respectively. The contamination rate of the sawdust media before inoculation was measured as 0, $4.5{\times}10$, $1.3{\times}10^2$, $4.0{\times}10^3cfu$ at $5^{\circ}C$, $10^{\circ}C$, $15^{\circ}C$, and $24^{\circ}C$ respectively. The average of $1.6{\times}10^8$ colony forming units (cfu) of microorganisms was observed in the sawdust that had been piled for six months outdoors. In summer, the sawdust has to be used immediately after mixing. The sterilized medium had an average of $4{\times}10^3cfu$ of microorganisms at $24^{\circ}C$ and $1.3{\times}10^2cfu$ at $15^{\circ}C$. After 15 days of inoculation in vitro, the growth conditions of the sawdust was the best at 132 mm, followed by grain and liquid. When inoculated with liquid spawn, the moisture content of the substrate should be adjusted between 50% and 55% in advance.

• Journal of Microbiology and Biotechnology
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• 제30권4호
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• pp.552-560
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• 2020

Human carbonic anhydrase (CA) isozyme II has been used as protein target for disorder treatment including glaucoma. Current clinically used sulfonamide-based CA inhibitors can induce side effects, and so alternatives are required. This study aimed to investigate a natural CA inhibitor from Murraya paniculata. The previously developed yeast-based assay was used to screen 14 compounds isolated from M. paniculata and identified by NMR analysis for anti-human CA isozyme II (hCAII) activity. Cytotoxicity of the compounds was also tested using the same yeast-based assay but in a different cultivation condition. Two flavonoid candidate compounds, 5, 6, 7, 8, 3', 4', 5'-heptamethoxyflavone (4) and 3, 5, 7, 8, 3', 4', 5'-heptamethoxyflavone (9), showed potent inhibitory activity against hCAII with a minimal effective concentration of 10.8 and 21.5 μM, respectively, while they both exhibited no cytotoxic effect, even at the highest concentration tested (170 μM). The results from an in vitro esterase assay of the two candidates confirmed their hCAII inhibitory activity with IC₅₀ values of 24.0 and 34.3 μM, respectively. To investigate the potential inhibition mechanism of compound 4, in silico molecular docking was performed using the FlexX and SwissDock software. This revealed that compound 4 coordinated with the Zn²⁺ ion in the hCAII active site through its methoxy oxygen at a distance of 1.60 Å (FlexX) or 2.29 Å (SwissDock). The interaction energy of compound 4 with hCAII was -13.36 kcal/mol. Thus, compound 4 is a potent novel flavonoid-based hCAII inhibitor and may be useful for further anti-CAII design and development.

• 한국유기농업학회지
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• 제23권4호
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• pp.939-950
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• 2015

The purpose of this study was to estimate the growth promoting effects and improvement of antioxidant activity of the soybean sprouts treated with Chlorella sp. culture solution. The soybean sprout treated with 0.1% and 0.2% Chlorella sp. culture solution was significantly increased the length (more than 43.0%), the thickness (more than 0.5~0.7 mm), fresh weight (more than 2.9~3.7 g) compared to non-treated control in vitro. In organic soybean sprouts farm, the 0.2% chlorella culture solution applied to mass culture of soybean sprout and the fresh weight of soybean sprouts increased by more than 25% and the yield was very high as 598.33% compared to untreated control. In addition of sensory test, there is no fishy odor and better crunchy texture and nutty flavor for the treatment soybean sprouts compared to untreated soybean sprouts. Particularly, free-radical scavenging activity (DPPH) and superoxide dismutase activity (SOD) of the soybean sprouts were significantly increased more than 26.1% and 40.4%, respectively by treated with 0.1% and 0.2% Chlorella culture solution. Consequently, the treatment of chlorella culture solution to grow soybean sprouts is also promoting quality and antioxidant activity as well as promoting the growth of sprouts. Therefore, chlorella is considered to be worth as functional materials for high-quality sprouts grown.

• 한국식물병리학회지
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• 제10권2호
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• pp.112-118
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• 1994

Forth microbial isolates out of 167 isolates from the soil of controlled cultivation areas inhibited mycelial growth of Rhizoctonia solani AG2-1 causing the strawberry bud rot in vitro. Among the isolates, Kr013 and Kr020 showed suppressive effect to R. solani AG2-1 on seedlings of chinese cabbage treated by root immersion, charcoal carrier granule and drenching on 1.0% infested soil in pot. Furthemore, the corresponding effect was also revealed when the charcoal carrier granule of the isolates were treated on the seedling of strawberry that were planted on the planting hole in pot. To examine the effects of biological control in green house, it had been tested the infection rates by using two different treatments. First, the strawberry runner were planted on the nursery soil mixed with 20% charcoal carrier granule of Kr013 and Kr020 isolate respectively, and grown for 20 days before transplanting. Then the young plants form the mother plant were separated and transplanted on the 1.0% infested soil. Another method was that the charcoal carrier of Kr013 and Kr020 isolates applied to planting hole of 1.0% infested soil just before transplanting. Then the young plants were grown for 20 days on the sterilized nursery soil before transplanting. From the results, the effects of biological control was significantly higher on former treatment (e.g. the infection rates were 7.3 and 5.7%, respectively) than on the latter treatment (e.g. the corresponding value were 16.7 and 15.7%, respectively). The antagonistic isolates of Kr013 and Kr020 were respectively identified as Pseudomonas cepacia with the similarity of 55.0% and 60.0% by using the Biolog GN Microplate system.

• 한국초지조사료학회지
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• 제25권1호
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• pp.17-22
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• 2005

This experiment was conducted to investigate the effect of seeding dates and rates on the productivity and nutritive value of hairy vetch(Vicia villosa Roth) at experimental field of Grassland and Forage Crops Division, National Livestock Research Institute, RDA, Suwon from 1999 to 2000. The experimental design was consisted of split-plot design with three replications. The main plot was seeding dates(25 Aug., 15 Sep. and 5 Oct.) and the subplot was seeding rates(20, 30 and 40 kg/ha). Late seeding dates increased the plant height and delayed the flowering stage as 1 or 2 days. The dry matter(DM) content was decreased with low seeding rates, and the trend was same in the all plots. Average crude protein(CP) content was $24.1\%$ and increased with delayed seeding date and lower seeding rate. The content of acid detergent fiber(ADF) and neutral detergent fiber(NDF) was increased with higher seeding rate, but seeding date did not affect. In vitro dry matter digestibility(IVDMD) of hairy vetch tended to decrease with high seeding rate, and total digestible nutrient(TND) did not show significant difference among seeding rates. Average relative feed value(RFV) of hairy vetch showed 140 which means very high quality. Dry matter and CP yield was decreased with delayed seeding date. The results of this experiments indicated that seeding in middle-August with 40 kg/ha would be recommended to produce the highest yield and quality f3r the cultivation of hairy vetch in middle part of Korea