• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.74.1-74
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• 2003

Differential display (DD) of mRNA is a technique in which mRNA species expressed by a cell population are reverse transcribed and then amplified by many separate polymerase chain reactions (PCR). Using DD-RT-PCR we obtained many genes that expressed differentially in healthy and PVX-infected Nicotiana benthamima, using total RNAs extracted from healthy and PVX-infected N. benthamiana plants. Three hundred and twenty-five DNA fragments isolated from DD-RT-PCR were cloned and sequenced for further characterization. Several host genes including SKPI-like protein, heat shock transcription factor and Avr9/Cf-9 rapidly elicited protein were selected to obtain full-length open reading frame and to characterize their potential involvement in virus disease development and/or host's defense against virus infection employing PVX-based expression vector. Transcrips from wild-type and clones containing each selected gene were inoculated onto N. benthamiana Levels of virus replication were confirmedby RT-PCR and RNA blot analysis, Expression profiles and potential role(s) of selected genes upon PVX infection will be discussed.

• Food Science and Biotechnology
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• 제17권6호
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• pp.1341-1344
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• 2008

The present study was conducted to investigate the effects of flowers ethanol extract of Elsholtzia splendens (ESE) on the antioxidant defence system in mice with 7,12-dimethylbenz(a)anthracene (DMBA)-induced oxidative stress. The ESE was pre-administered orally to 2 groups of mice at 10 and 50mg/kg body weight (BW) for 5 weeks. Subsequently, mice with pretreatment of ESE received DMBA intragastrically at a dose of 34 mg/kg BW twice a week for 2 weeks. In DMBA alone group, biomarkers of oxidative stress (TBARS value, carbonyl content, and serum 8-OH-dG) were significantly increased. Also, the antioxidant enzymes were down-regulated. ESE significantly restored the TBARS value and carbonyl content at both doses, while a decrease in the elevated serum 8-OH-dG content was observed only at the higher dose. The DMBA-induced decreases in catalase and superoxide dismutase (SOD) activities were restored to nearly control levels by ESE. Glutathione peroxidase (GSH-px) and glutathione reductase (GR) activities, as well as the reduced glutathione (GSH)/oxidized GSH (GSSG) ratio, were significantly affected by ESE at the higher dose. These results suggest that ESE possesses antioxidant activity, which plays a protective role against DMBA-induced oxidative stress.

• The Plant Pathology Journal
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• 제34권2호
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• pp.126-138
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• 2018

Rice blast caused by Magnaporthe oryzae is a major disease. In the present study, we aimed to identify and evaluate the novel bacterial isolates from rice rhizosphere for biocontrol of M. oryzae pathogen. Sixty bacterial strains from the rice plant's rhizosphere were tested for their biocontrol activity against M. oryzae under in vitro and in vivo. Among them, B. amyloliquefaciens had significant high activity against the pathogen. The least disease severity and highest germination were recorded in seeds treated with B. amyloliquefaciens UASBR9 (0.96 and 98.00%) compared to untreated control (3.43 and 95.00%, respectively) under in vivo condition. These isolates had high activity of enzymes in relation to growth promoting activity upon challenge inoculation of the pathogen. The potential strains were identified based on 16S rRNA gene sequencing and dominance of these particular genes were associated in Bacillus strains. These strains were also confirmed for the presence of antimicrobial peptide biosynthetic genes viz., srfAA (surfactin), fenD (fengycin), spaS (subtilin), and ituC (iturin) related to secondary metabolite production (e.g., AMPs). Overall, the results suggested that application of potential bacterial strains like B. amyloliquefaciens UASBR9 not only helps in control of the biological suppression of one of the most devastating rice pathogens, M. grisea but also increases plant growth along with a reduction in application of toxic chemical pesticides.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2003년도 생물공학의 동향(XII)
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• pp.293-297
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• 2003

본 연구에서는 형질전환된 N. tabacum 배양에 있어서 glutathione과 ascorbic acid가 세포 생장과 생존율에 미치는 영향을 비교하여 실험하였다. Glutathione과 ascorbic acid의 첨가는배양초기 세포 생존율의 감소를 완화시켰으며, 그로인한 재조합 단백질의 생산성 증대를 확인할 수 있었다. 또한 glutathione과 ascorbic acid를 첨가하여 배양한 세포는 cold stress로 인한 세포 생존율의 감소와 DNA 절편화를 억제 시키는데 효과가 있었다. 변형시킨 FDA법에 의한 세포 생존율은 배양 6일째 최대를 보였으며, 고 삼투압 배지와 저온의 환경은 세포 생존율을 저하시켰다. 반면 cold stress 전에 glutathione과 ascorbic acid를 첨가하여 배양한 세포의 생존율은 cold stress 후, 대조구 세포보다 높게 유지되었으며, DNA 절편화 현상도 cold stress 후, 대조구 세포보다 적게 일어남을 확인하였다. 따라서 glutathione과 ascorbic acid는 cold stress로 의한 세포 생존율 저하를 완화시키며, apoptosis 억제 효과가 있다고 판단된다.

• Asian-Australasian Journal of Animal Sciences
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• 제12권3호
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• pp.467-480
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• 1999

Many antinutritional and toxic factors abound in tropical seeds, which are also generally rich in nutrients and therefore more prone to attack from herbivores. Antinutritional and toxic factors are considered to defend seeds against environmental vagaries and thus help to protect them. These factors though good for the plant, cause deleterious effects or are even toxic to animals and man. The conventional seeds cultivated for oil or non-oil purposes, and general aspects of antinutritional factors are not presented here as these have already been discussed widely by many workers. Deficits in conventional protein and energy sources in the tropics have stimulated a quest for alternative feeds both for animals and humans. This article attempts to highlight two new oilseed crops, Jatropha curcas and Moringa oleifera, and in addition deals with some under-utilized seeds with potential as animal feed. Most of these seed plants are adapted to various marginal growing conditions in the tropics and can help to mitigate the prevailing deficit in protein and energy sources. Antinutritional and toxic factors in seed or seed meal, various approaches to detoxify seed meal, and future research and development priorities for their exploitation as animal feeds are presented.

• ALGAE
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• 제23권3호
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• pp.163-175
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• 2008

Phenolic compounds play a major role in the interaction of plants with their environment. They are thought to have been a feature of higher plants since early colonization of the land. Phenolics are crucial for many important aspects of plant life. They can play structural roles in different supporting or protective tissues, for example in cell walls, they can be involved in defence strategies, and signalling properties particularly in the interactions between plants and their environment. In brown algae, phenolic compounds are contained within membrane bound vesicles known as physodes, and their roles in algae are thought to be similar to those of higher plant phenolics. They can be stained using various histochemical stains, however, none of these stains are phenolic specific so care must be taken during interpretation of such results. Many, but not all phenolics are also autofluorescent under UV or violet light. Physodes are involved in cell wall construction, both in primary and secondary walls in brown algae. They bind together with other wall components to make a tough wall. They have also been found to play a role at fertilization, in blocking polyspermy in some species. Sperm are very quickly rendered immobile after phenolic release from newly fertilized zygotes seconds after fertilization. Phenolic compounds are thought to be important herbivore deterrents in some species due to their astringent nature. Phenolic compounds also offer effective UV protection in the early life stages and also the adults of many algal species. In the future, this factor may also make them an important player in the pharmaceutical and skincare industries.

• The Plant Pathology Journal
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• 제29권1호
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• pp.77-86
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• 2013

Anthracnose development by Colletotrichum musae was observed to be significantly less in the fruits of the banana cultivar 'Embul' (Mysore, AAB) infected with Phyllosticta musarum than in fruits without such infections. Anthracnose disease originates from quiescent C. musae infections in the immature fruit. P. musarum incites minute, scattered spots, referred to as freckles, in the superficial tissues of immature banana peel which do not expand during maturation or ripening. P. musarum does not appear to have a direct suppressive effect on C. musae as conidia of C. musae germinate on both freckled and non-freckled fruit forming quiescent infections. Our investigations have shown that P. musarum infection induced several defence responses in fruit including the accumulation of five phytoalexins, upregulation of chitinase and ${\beta}$-1,3-glucanase, phenylalanine ammonia lyase (PAL) activity and cell wall lignification. $^1H$ and $^{13}C$ NMR spectral data of one purified phytoalexin compared closely with 4'-hydroxyanigorufone. Some of the P. musarum-induced defences that retained during ripening, restrict C. musae development at the ripe stage. This paper examines the potential of P. musarum-induced defences, in the control of anthracnose, the most destructive postharvest disease in banana.

• 한국추진공학회지
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• 제18권3호
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• pp.56-61
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• 2014

본 연구에서는 침식연소를 고려한 내탄도 프로그램을 이용하여 침식연소 모델에 따른 해석결과를 비교하였다. 동일한 추진제를 적용한 이형 그레인 형상을 적용한 추진기관의 연소 시 연소실 압력 변화를 비교 분석하여 연소가스의 유량 변화에 따른 침식연소 경향성 변화를 고찰 하였다. 고찰 결과 연소 면적이 클수록 연소실 단면적이 작을수록 침식연소 경향이 증가함을 알 수 있었다.

• Asian Pacific Journal of Cancer Prevention
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• 제13권6호
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• pp.2943-2948
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• 2012

Arsenic exposure is a serious health hazard worldwide. We have previously established that it may result in immune suppression by upregulating Th2 cytokines while downregulating Th1 cytokines and causing lymphocytic death. Treatment modalities for arsenic poisoning have mainly been restricted to the use of chelating agents in the past. Only recently have combination therapies using a chelating agent in conjunction with other compounds such as anti-oxidants, micronutrients and various plant products, been introduced. In the present study, we used T11TS, a novel immune potentiating glycopeptide alone and in combination with the sulfhydryl-containing chelator, mono-iso-amyl-dimarcaptosuccinic acid (MiADMSA) as a therapeutic regimen to combat arsenic toxicity in a mouse model. Results indicated that Th1 cytokines such as TNF-${\alpha}$, $IFN{\gamma}$, IL12 and the Th2 cytokines such as IL4, IL6, IL10 which were respectively downregulated and upregulated following arsenic induction were more efficiently restored to their near normal levels by T11TS alone in comparison with the combined regimen. Similar results were obtained with the apoptotic proteins studied, FasL, BAX, BCL2 and the caspases 3, 8 and 9, where again T11TS proved more potent than in combination with MiADMSA in preventing lymphocyte death. The results thus indicate that T11TS alone is more efficient in immune re-establishment after arsenic exposureas compared to combination therapy with T11TS+MiADMSA.

• Journal of Plant Biotechnology
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• 제31권4호
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• pp.313-317
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• 2004

MMPs는 $Zn^{2+}$-의존성 endopeptidase로서 세포외 기질을 분해하는 능력을 갖고 있다. 본 연구에서는 담배식물체에서 잎의 발생단계별로 분비되는 MMPs의 활성과 환경 스트레스에 의한 MMPs의 활성을 조사하였다. 그 결과 MMPs의 활성은 기부 부위의 완전히 성숙한 잎보다 엽신의 확장이 일어나고 있는 어린잎에서 높았다. 이는 식물체에서 잎 신장을 위한 세포내 공간 형성 및 조직재구성에 MMPs가 중요한 단백질분해효소로 작용함을 시사하였다. 또한 환경 스트레스에 대한 반응으로서 MMPs의 활성을 조사한 결과 염처리와 병원균 감염에 의해 각각 1.2배와 1.5배의 증가를 보였다. 이러한 결과는 식물체가 발생단계 외에도 불리한 환경에 대한 방어 수단으로 MMPs가 생성 분비함을 알 수 있었다.