• 한국양봉학회지
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• 제33권4호
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• pp.283-295
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• 2018

As Sacbrood virus (SBV), a causative agent of larval death and colony collapse in Apis cerana honey bee, is prevalent and poses one of the most significant threats to the Korean apiculture, development of methods to counter this viral disease is urgently needed. In this study we tested some SBV controlling methods, such as requeen, shook swam, adding Apis mellifera and spraying yogurt to SBV inoculated colony. Colony size measured by number of sealed brood and adult were evaluated every 15 days until two months while instances of recurrence were recorded up to five months after applying treatment methods. We also test the effects of yogurt on healthy and SBV-infected larvae at both in vitro reared larvae and colony level. Our result showed that all SBV controlling methods had similar success rates with respect to elimination of SBV clinical symptom up to 30 days post treatment. Mix-species and spraying yogurt method had similar pattern of sealed brood and adult number and higher than that of other SBV controlling methods up to 45 days post treatment. These two groups also showed the lower percentage of SBV recurrence (50% and 66.7%) at 120 days post treatment than other group that mostly colony had clinical symptom. Result on in vitro reared larvae challenged with yogurt showed that yogurt have neither harmless on healthy larvae nor remedial effect on SBV infected larvae. However, at colony level, colony in group received yogurt treatment removed significantly more SBV-infected larvae, SBV-killed larvae, and even healthy larvae in comparison to the control, suggested that yogurt could trigger the hygienic behavior of nurse bee. Our results recommended that it is practical in beekeeping by adding A. mellifera and spraying yogurt to control SBV in A. cerana colony.

• 한국임상수의학회지
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• 제38권1호
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• pp.27-31
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• 2021

Shea butter (Vitellaria paradoxa) is a fat extracted from shea tree nuts and contains relatively high levels of non-glycerides. Triterpenes, the main non-glyceride component, exhibit a variety of biological activities such as antitumor, antibacterial, and anti-inflammatory. Shea butter extract (SBE) has been used to treat various skin problems such as burns, eczema, and rash in human medicine, but little is known about the activity of SBE on canine skin. This study evaluated the cytotoxicity and anti-inflammatory effect of SBE in canine keratinocytes. Cytotoxicity of lipopolysaccharide (LPS, 5-50 ng/mL) and SBE (50-200 ㎍/mL) was evaluated using the CCK-8 assay. Non-cytotoxic concentrations of LPS and SBE were administered to canine cell cultures to evaluate anti-inflammatory effects. To evaluate the anti-inflammatory activity of SBE, the levels of IL-1β, IL-8, IL-12, and TNF-α were measured using ELISA kits. The concentration of each cytokine was quantified in control, LPS-treated, LPS + SBE-treated groups. Increased levels of IL-1β, IL-8, and IL-12 were found in LPS-treated groups relative to control groups. LPS + SBE-treated groups showed a lower level of IL-1β, IL-8, and IL-12 than LPS-treated groups. These results suggest that SBE may have application as a topical agent for canine inflammatory skin diseases. However, further in vivo study is needed to evaluate the safety and efficacy of SBE in dogs.

• 대한수의학회지
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• 제61권2호
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• pp.14.1-14.7
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• 2021

Biosilica is a silica-based substance derived from the cell walls (frustules) of diatoms. Recently, research into biosilica's biological functions is underway, but little has been reported on the effects of biosilica on immune cells. In this study, we investigated the effect of ionized biosilica water (iBW) on dendritic cells (DCs), which play crucial roles as antigen (Ag)-presenting cells. Treatment with iBW increased the expression of immune response-related markers, closely connected to the maturation of DCs, and the production of tumor necrosis factor-alpha. In addition, iBW-treated DCs (iBW-DCs) had a lower uptake of fluorescein isothiocyanate-dextran than that of control DCs. Mixed leukocyte response analysis used for measuring the Ag-presenting capability of DCs, showed iBW-DCs had a higher capability than that of control DCs. Interestingly, DCs treated with lipopolysaccharide (LPS) and iBW had a lower level of Ag-presenting capability than that of LPS-treated DCs. Taken together, the results indicate that iBW alone can mature DCs, but it decreases the Ag-presenting capability of DCs in the presence of LPS, a representative agent of inflammation. This study may provide valuable information regarding the effect of iBW on immune cells. Further research is needed to investigate how iBW induces the observed biphasic immunomodulatory activity.

• The Plant Pathology Journal
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• 제39권1호
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• pp.39-51
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• 2023

Common bean (Phaseolus vulgaris L.) is one of the most important crops in human food production. The occurrence of diseases, such as white mold, caused by Sclerotinia sclerotiorum can limit the production of this legume. The use of Trichoderma has become an important strategy in the suppression of this disease. The aim of the present study was to evaluate the effect of volatile organic compounds (VOCs) emitted by Trichoderma azevedoi CEN1241 in five different growth periods on the severity of white mold in common bean. The in vitro assays were carried out in double-plate and split-plate, and the in vivo assays, through the exposure of the mycelia of S. sclerotiorum to the VOCs of T. azevedoi CEN1241 and subsequent inoculation in bean plants. Chemical analysis by gas chromatography coupled to mass spectrometry detected 37 VOCs produced by T. azevedoi CEN1241, covering six major chemical classes. The profile of VOCs produced by T. azevedoi CEN1241 varied according to colony age and was shown to be related to the ability of the biocontrol agent to suppress S. sclerotiorum. T. azevedoi CEN1241 VOCs reduced the size of S. sclerotiorum lesions on bean fragments in vitro and reduced disease severity in a greenhouse. This study demonstrated in a more applied way that the mechanism of antibiosis through the production of volatile compounds exerted by Trichoderma can complement other mechanisms, such as parasitism and competition, thus contributing to a better efficiency in the control of white mold in bean plants.

• 한국버섯학회지
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• 제12권1호
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• pp.35-40
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• 2014

버섯 세균갈성색무늬병원균인 Pseudomonas tolaasii에 대한 독소저해균으로 보고된 Pseudomonas sp. HC1 균주의 배양적 특성과 최적 배양을 위한 대량배지를 선발하였다. CH1균주의 생육온도는 $20{\sim}40^{\circ}C$, pH는 5.0~11.0까지 넓은 범위에서 왕성한 생육을 보였다. 대량배양을 위한 효율적인 영양원 선발을 위하여 기본배지에 탄소원 fructose 등 18종, 무기질소원 $NH_4Cl$ 등 6종, 유기질소원 peptone 등 6종 그리고 아미노산 asparagine 등 11종을 각각 1%씩 첨가하였고, 무기염류 13종을 1 mM 농도로 첨가하여 각각에 대한 생육에 미치는 영향을 조사하였다. 또한 선발된 각각의 영양성분들에 대한 최적 농도를 조사하기 위하여 각각의 성분을 0.1%에서 4.0%까지 배지에 첨가하여 배양후 생육정도를 조사하였다. 그 결과, 대량배양을 위한 생육최적조건은 온도 $20^{\circ}C$, pH5, 탄소원 0.9% dextrine, 유기질소원 1.5% yeast extract, 무기질소원 0.5% $(NH_4)_2HPO_4$, 아미노산 3.0% cysteine, 무기염류 4 mM $FeCl_3$에서 왕성한 생육을 보였다.

• 한국응용곤충학회지
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• 제52권4호
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• pp.283-289
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• 2013

본 연구는 온도(15, 20, 25, $30^{\circ}C$), 습도($70{\pm}10%$), 광주기(16L:8D)에서 갈고리뱀잠자리붙이의 생물적 특성을 조사하기 위해 수행되었다. 알에서부터 번데기까지의 발육영점온도 및 유효적산온도는 각각 $9.6^{\circ}C$ 및 270.3일도였다. $25^{\circ}C$에서 갈고리뱀잠자리붙이의 알 기간은 4.4일, 유충은 5.5일, 번데기는 6.9일이었다. 암컷 성충의 수명은 34.9일, 산란 기간은 28.7일이었고, 총 산란수는 515.2개, 1일 최대 산란수는 54.8개였다. $25^{\circ}C$에서 갈고리뱀잠자리붙이에 의한 싸리수염진딧물의 1령, 2령, 3령 및 성충의 일일 포식량은 각각 18.9, 47.2, 57.7 및 91.0마리이었다. 따라서 갈고리뱀잠자리붙이는 진딧물의 포식성 천적으로 이용이 가능할 것으로 여겨진다.

• ALGAE
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• 제22권4호
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• pp.287-295
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• 2007

Infection of free-living dinoflagellates by endoparasitic dinoflagellates of the genus Amoebophrya are thought to have significant impacts on host population dynamics and have long been proposed to be a potential biological agent for controlling harmful algal bloom (HAB). To understand the impact of Amoebophrya on particular host species, however, it is necessary to quantify aspects the parasites life cycle. Here we used cultures of Amoebophryahost systems from Jinhae Bay, Korea to determine, parasite generation time, and dinospore survival and infectivity. The proportion of host cells infected by Amoebophrya sp. changed sharply from 5% to 87% with increasing dinospore:host inoculation ratios. In the absence of H. triquetra, most free-living dinospores died within 72 hours and their ability to infect host cells decreased remarkably in a day. The relatively short free-living phase of Amoebophrya suggests that the spread of infections is most likely to occur during seasons of high host abundance, as that is when dinospores have the greatest chance of encountering host cells. Infection of host cells inoculated with dinospores during the day was higher than when inoculated during the night, suggesting that infection rates might be related to environmental light conditions and/or diurnal biological rhythm of host species. Total generation times of parasite strains from a thecate dinoflagellate Heterocapsa triquetra were nearly the same regardless of dinospore:host inoculation ratios, representing 54 ± 0.5 h in a 1:1 ratio and 55 ± 1.2 h in a 20:1 ratio. Dinospore production of Amoebophrya sp. infecting Heterocapsa triquetra was estimated to be 125 dinospores per a strain of Amoebophrya sp. There is a growing need to maintain a variety of host-parasite systems in culture and to examine their autecology under various environmental conditions. Such studies would be very helpful in understanding ecological role of these parasites, their overlooked importance in the flow of material and energy in marine ecosystem, and their practical use as biological control agents applied directly to areas affected by HAB.

• Applied Biological Chemistry
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• 제48권1호
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• pp.40-47
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• 2005

진균성식물병을 생물학적으로 방제할 수 있는 미생물제제의 개발을 위하여 경북 지역의 저병해 경작지 토양에서 고추역병균 Phytophthota capsici과 시들음병균 Fusarium oxysporum에 강력한 길항능을 가지며 균주 상호간에 공생이 가능한 AY1, AY6, AB1, BB2, F4, 5종의 균주를 선발하였다. 이들의 P. capsici에 대한 길항기작은 모두 내열성 저분자의 항균성 항생물질 생산에 의한 것이었으며, 이 중 BB2균주는 항생물질 생산능뿐만 아니라 고추역병균의 세포의벽 가수분해효소인 cellulase도 생산하여 다기능 길항기작을 보유하고 있었다. 선발된 5종 균주는 Halobacterium sp. AB1, Xenorhadus sp. AY1, Bacillus sp. AY6, Bacillus sp. BB2, Zymomonas sp. F4로 각각 동정되었으며, 이들은 0.1% galactose, 0.1% $NaNO_2$, 5 mM $Na_2HPO_4$가 포함된 배지에서 pH 5.5의 조건에서 48시간 배양했을 때 길항물질 생산능이 매우 우수하였고, 이 배양액을 1톤 규모의 발효탱크에 접종하고 대량배양 후 복합 미생물제제로 생산하였으며, 생산된 시제품의 액상 미생물제제는 경북 영천지역의 농가의 시험포장에서 3일 간격으로 3회 처리 해 본 포장시험에서 오이덩굴쪼김병, 방울토마토시드름병의 방제와 시금치잘록병의 방제 및 생육촉진에 탁월한 효과가 있었다.

• 한국응용곤충학회지
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• 제46권1호
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• pp.79-85
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• 2007

2005-2006년 알락수염노린재(Dolycoris baccarum)의 알 기생천적 조사에서 Trissolcus nigripedius가 안동, 밀양, 남해, 수원의 4지역에서 분포하고, 알락수염노린재의 주요 알 기생천적임을 알 수 있었다. 또한 2005년 밀양과 안동에서 채집한 가로줄노린재와 톱다리개미허리노린재의 알이 T. nigripedius에 의해 기생되어 있음을 발견하고, 알락수염노린재 외 4종의 콩 노린재류에 대한 기생여부를 확인하기 위해 기주수용행동을 관찰하였다. T. nigripedius는 알락수염노린재, 가로줄노린재, 썩덩나무노린재의 알에 대해서만 3가지 기주수용행동(촉각으로 더듬기 (drumming), 산란관으로 찌르기[oviposition], 표지[marking]) 모두를 보여주었다. 가로줄노린재의 경우 24시간 동안 알을 공급한 후 기주 알에서의 기생벌 우화율이 75%이고, 공급한 기주 알에 대해 3가지 기주수용행동을 보인 비율에서는 원래 기주인 알락수염 노린재와 차이가 없었다. 그러나 썩덩나무노린재의 알에서는 52%에서만 표지행동을 관찰할 수 있었고, 기생벌은 우화하지 못하였다. 톱다리개미허리노린재나 풀색노린재의 알에서는 더듬기와 산란관으로 찌르기를 했지만 표지를 하지 않은 것으로 보아 산란 그 자체를 하지 않았으며 기생벌이 우화하지도 않았다. 하지만 톱다리개미허리노린재의 경우에는 알을 24시간 동안 기생벌에 노출시켰을 때 약 20%가 기생되었고 30%가 치사하였다. 따라서 알락수염노린재와 가로줄노린재의 생물적 방제뿐만 아니라 톱다리개미허리노린재의 밀도억제에도 유효한 천적이 될 것이다.

• 미생물학회지
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• 제52권4호
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• pp.437-443
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• 2016

여러 토양에서 분리한 400여 개의 방선균 균주에 대해 4가지 식물병원성 진균에 대한 항진균 활성을 조사하였으며 그 중 Streptomyces costaricanus HR391 균주는 PDB 배지에서 식물병원성 진균인 Fusarium oxysporum f. sp. raphani, F. oxysporum f. sp. niveum, F. oxysporum f. sp. lycopersici와 Rhizoctonia solani의 균사 생장을대조군과 비교하여 각각 26.5, 26.2, 21.2와 23.8% 저해하였다. S. costaricanus HR391은 항진균물질인 siderophore를 $98{\mu}M$을 생성할 뿐만 아니라 유화활성을 나타내며 막지질을 파괴할 수 있는 생물계면활성제인 rhamnolipid와 lipopeptide인 iturin A와 surfactin를 생성하였다. 또한 진균 세포막을 분해할 수 있는 chitinase와 glucanase 활성도 나타내었으며 병원균의 막을 파괴하는 AMP와 항생물질 phenazine도 분비하였다. 이외에도 식물생장 촉진활성을 갖는 zeatin, gibberellin과 indole acetic acid 같은 식물호르몬도 생성하였다. 이와 같이 항진균 활성을 나타내는 S. costaricanus HR391 균주는 다양한 종류의 항진균 물질의 상승작용과 더불어 높은 생물계면활성이 본 균주의 항진균 활성에 큰 역할을 하는 것으로 보이며 친환경적인 생물학적 항진균제로서 활용이 가능할 것으로 기대된다.