• 한국약용작물학회지
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• 제16권2호
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• pp.94-99
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• 2008

인삼의 생장에서 염류의 집적은 우량 인삼의 생산에 많은 장애요인이 되고 있다. 본 연구에서는 순계 분리된 인삼의 우수 계통으로부터 NaCl 처리에 따른 생장율 조사와 ginsenoside의 생산에 미치는 영향을 조사하였다. 선발된 모상근(KGHR-8)으로부터 ginsenosides의 함량에 미치는 NaCl의 최적 농도를 조사하기 위하여 30일간 배양한 결과 NaCl의 농도가 증가함에 따라 모상근의 생장은 감소하였지만, total ginsenoside의 함량은 0.24M NaCl 처리구에서 높은 증가를 가져왔으며 특히 광을 조사하여 배양한 결과 높게 검출되었다. 0.24 M NaCl 농도로 광상태하에서 함량은 61.7% 증가하는 양상을 나타내었다. (Table 1). 또한 모상근의 생장을 최적 상태로 설정하기 위해 two step culture 방법을 조사한 결과, 0.05M, 0.1M NaCl 처리시 모상근의 생장율은 각각 약 62%, 76% 감소한 반면, ginsenoside의 함량은 29%, 48% 각각 향상되었다. 모상근은 방어기작의 일환으로 NaCl을 elicitor로 인지하고 2차대사산물인 사포닌의 생산에 영향을 미치는 것으로 확인되었다.

• The Plant Pathology Journal
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• 제30권2호
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• pp.220-227
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• 2014

The GacS/GacA system in the root colonizer Pseudomonas chlororaphis O6 is a key regulator of many traits relevant to the biocontrol function of this bacterium. Proteomic analysis revealed 12 proteins were down-regulated in a gacS mutant of P. chlororaphis O6. These GacS-regulated proteins functioned in combating oxidative stress, cell signaling, biosynthesis of secondary metabolism, and secretion. The extent of regulation was shown by real-time RT-PCR to vary between the genes. Mutants of P. chlororaphis O6 were generated in two GacS-regulated genes, trpE, encoding a protein involved in tryptophan synthesis, and prnA, required for conversion of tryptophan to the antimicrobial compound, pyrrolitrin. Failure of the trpE mutant to induce systemic resistance in tobacco against a foliar pathogen causing soft rot, Pectobacterium carotovorum SCCI, correlated with reduced colonization of root surfaces implying an inadequate supply of tryptophan to support growth. Although colonization was not affected by mutation in the prnA gene, induction of systemic resistance was reduced, suggesting that pyrrolnitrin was an activator of plant resistance as well as an antifungal agent. Study of mutants in the other GacS-regulated proteins will indicate further the features required for biocontrol-activity in this rhizobacterium.

• Journal of Forest and Environmental Science
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• 제24권2호
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• pp.79-88
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• 2008

Twenty-eight of 44 Indian Ceropegia species are endemic and their survival is threatened. As a step towards conservation, we implied in vitro methods for the sustainable propagule production in C. hirsuta, C. lawii, C. maccannii, C. oculata and C. sahyadrica. Effects of explant, growth regulators, sucrose and photoperiod were studied. High frequency microtuber production was achieved with the seedling-apical buds, grown on MS medium containing 4-6 mg $1^{-1}$ BAP, 3-8% (w/v) sucrose, under continuous illumination. Each microtuber, when subcultured proliferated to form a cluster of secondary microtubers. Every primary and secondary microtuber bore at least one shoot-bud and a root primordium. Each tuber (formed with any of the significantly effective treatments) weighed more than 500 mg, enough to plant directly in non-sterilized soils. Microtubers could be produced and proliferated round the year. Proliferation could be solely attributed to in vitro procedures as these plants bear solitary tubers in vivo. Microtubers could be sprouted in vitro to prepare ready to pot plantlets. As, this novel method succeeded for all five species, though they belong to different eco-physiological backgrounds, we recommend its implementation in the conservation programs for a broader range of Ceropegia species, supported by other integrated strategies.

• 한국작물학회지
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• 제39권3호
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• pp.295-305
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• 1994

본 실험은 alfalfa 와 vetch의 추출물과 잔유물의 콩과 옥수수에 대한 타감작용을 검정하기 위해서 실시 되었다. 콩과 옥수수에 대한 타감작용을 검정하기 위해서 영양생장기 때에 수확된 alfalfa 와 vetch를 건조시켜 추출물을 얻었고 또한 이들 잔기를 silica sand와 혼합처리하여 콩과 옥수수의 생육을 검토 하였고, 콩에 대해서는 근류균의 착생정도를 조사 하였다. 1. 발아시험에서는 롱과 옥수수의 발아율, 유근의 생장, 무게 등이 추출물 농도가 증가할수록 억제 되었으며, 최고 억제정도는 추출물 농도 20%에서 발생되었다. 추출물에 대하여 콩이 옥수수보다 더 민감하게 반응하였으며, alfalfa의 추출물이 vetch의 추출물보다 더 억제적이었다. 2. Alfalfa와 vetch를 silica sand에 혼합하여 콩과 옥수수의 간장, 엽면적, 지상부의 생육정도를 비교하였을 때 콩의 간장, 업면적, 지상부 생육은 alfalfa처리에서 더 억제적 이었으며, 옥수수의 생육은 vetch 처리에서 촉진 되었다. 3. Alfalfa와 vetch처리가 모두 콩 뿌리혹의 형성을 억제시켰는데 alfalfa처리가 vetch의 처리보다 뿌리혹의 형성을 더 억제 시켰다. 4. Alfalfa와 vetch의 추출물과 잔기의 처리는 옥수수보다는 콩의 발아와 생육에 더 억제적으로 작용하므로 콩 재배의 경우에는 이들 잔기의 관리가 필요하다고 생각되어진다.

• 한국축산식품학회지
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• 제35권1호
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• pp.108-113
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• 2015

The purpose of this study was to develop predictive models for the growth of Listeria monocytogenes in pork Bulgogi at various storage temperatures. A two-strain mixture of L. monocytogenes (ATCC 15313 and isolated from pork Bulgogi) was inoculated on pork Bulgogi at 3 Log CFU/g. L. monocytogenes strains were enumerated using general plating method on Listeria selective medium. The inoculated samples were stored at 5, 15, and $25^{\circ}C$ for primary models. Primary models were developed using the Baranyi model equations, and the maximum specific growth rate was shown to be dependent on storage temperature. A secondary model of growth rate as a function of storage temperature was also developed. As the storage temperature increased, the lag time (LT) values decreased dramatically and the specific growth rate of L. monocytogenes increased. The mathematically predicted growth parameters were evaluated based on the modified bias factor ($B_f$), accuracy factor ($A_f$), root mean square error (RMSE), coefficient of determination ($R^2$), and relative errors (RE). These values indicated that the developed models were reliably able to predict the growth of L. monocytogenes in pork Bulgogi. Hence, the predictive models may be used to assess microbiological hygiene in the meat supply chain as a function of storage temperature.

• 한국식품위생안전성학회지
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• 제28권2호
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• pp.168-173
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• 2013

본 연구는 신선편이 식품에서 오염 가능성이 있는 병원성 식중독 균 E. coli O157:H7에 대해 파프리카에서 성장 예측 모델을 적용하고, 본 연구에서 개발된 성장 예측 모델을 내부 검증하였다. 이를 비교하여 신선편이 식품을 안전하게 관리하기 위한 적절한 모델을 제시하고자 하였다. 파프리카에 E. coli O157:H7접종하여 온도에 따라 12, 24, 30, $36^{\circ}C$에 보관하여 성장을 측정하였다. Gompertz 식을 이용하여 온도에 따른 성장곡선을 그리고 LT와 SGR을 산출하였다. 산출된 LT와 SGR은 각각 Davey model와 squareroot model를 이용하여 2차 모델을 개발하였다. 개발된 2차 모델에 대하여 LT와 SGR model의 $R^2$값은 각각 0.999, 0.994로 1에 근접하는 높은 적합성을 보였다. 또한 내부 검정 결과 LT와 SGR model의 Bf 값은 각각 1.01, 0.89, LT model은 안전하게 SGR model 위험하게 예측되었다. 파프리카의 LT와 SGR의 상대적인 오차 값은 모두 허용 가능한 오차 범위에 포함 되었다. 따라서 개발된 모델을 이용하여 온도에 따른 E. coli O157:H7성장을 추정할 수 있으며, 이를 위해평가 자료로 활용할 수 있을 것으로 보인다.

• The Plant Pathology Journal
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• 제28권1호
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• pp.20-31
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• 2012

Endophytic bacterial communities of tidal flat plants antagonistic to oomycete plant pathogens were studied by the isolation of 256 root colonizing endophytic bacteria from surface-disinfected root tissues of six plants ($Rosa$ $rugosa$, $Suaeda$ $maritima$, $Vitex$ $rotundifolia$, $Carex$ $scabrifolia$, $Glehnia$ $littoralis$ and $Elymus$ $mollis$) growing in a tidal flat area of Namhae Island, Korea. To understand the antagonistic potential, an $in$ $vitro$ antagonistic assay was performed to characterize and identify strains that were antagonistic to the oomycete plant pathogens $Phytophthora$ $capsici$ and $Pythium$ $ultimum$ from the total population. Nine percent of the total number of isolated bacteria exhibited in vitro inhibitory activity against target plant pathogenic oomycetes. Taxonomic and phylogenetic placement of the antagonistic bacteria was investigated by analysis of the 16S rRNA gene sequences. The sequence analysis classified the antagonistic strains into four major classes of the domain bacteria ($Firmicutes$, ${\alpha}-Proteobacteria$, ${\gamma}-Proteobacteria$ and $Actinomycetes$) and 10 different genera. Further production of secondary metabolites, hydrolytic enzymes and plant growth promoting traits were determined for the putative new species of antagonistic endophytic bacteria. These new strains could not be identified as known species of ${\alpha}-Proteobacteria$, and so may represent novel bacterial taxa. The unexpected high antagonistic bacterial diversity associated with the tidal flat plants may be indicative of their importance in tidal flat plants as a promising source of novel antimicrobial compounds and biocontrol agents.

• Genes and Genomics
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• 제40권12호
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• pp.1287-1300
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• 2018

Hydrogen sulfide ($H_2S$), a small bioactive gas, has been proved functioning in plant growth and development as well as alleviation of abiotic stresses, which including promoting seed germination, accelerating embryonic root growth, regulating flower senescence, inducing stomatal closure, and defending drought, heat, heavy metals and osmotic stresses etc. However, the molecular functioning mechanism of $H_2S$ was still unclear. The primary objective of this research was to analyze the transcriptional differences and functional genes involved in the $H_2S$ responses. In details, 4-week-old plantlets in tissue culture of grapevine (Vitis vinifera L.) cultivar 'Zuoyouhong' were sprayed with 0.1 mM NaHS for 12 h, and then transcriptome sequencing and qRT-PCR analysis were used to study the transcriptional differences and functional genes involved in the $H_2S$ responses. Our results indicated that 650 genes were differentially expressed after $H_2S$ treatment, in which 224 genes were up-regulated and 426 genes were down-regulated. The GO enrichment analysis and KEGG enrichment analysis results indicated that the up-regulated genes after $H_2S$ treatment focused on carbon metabolism, biosynthesis of amino acids, and glycolysis/gluconeogenesis, and the down-regulated genes were mainly in metabolic pathways, biosynthesis of secondary metabolites, and plant hormone signal transduction. Analyzing the transcription factor coding genes in details, it was indicated that 10 AP2/EREBPs, 5 NACs, 3 WRKYs, 3 MYBs, and 2 bHLHs etc. transcription factor coding genes were up-regulated, while 4 MYBs, 3 OFPs, 3 bHLHs, 2 AP2/EREBPs, 2 HBs etc. transcription factor coding genes were down-regulated. Taken together, $H_2S$ increased the productions in secondary metabolites and a variety of defensive compounds to improve plant development and abiotic resistance, and extend fruits postharvest shelf life by regulating the expression of AP2/EREBPs, WRKYs, MYBs, CABs, GRIP22, FERRITINs, TPSs, UGTs, and GHs etc.

• 생물환경조절학회지
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• 제29권4호
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• pp.464-472
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• 2020

본 연구에서는 플라즈마 발생장치를 수경재배 시스템과 결합하여 재배 기간 동안 처리 시 상추의 생육 및 기능성 물질 함량 변화를 살펴보기 위해 실시하였다. 3주 동안 육묘하여 균일한 크기의 상추 묘를 semi-DFT에 정식하였으며, 플라즈마 공정 장치를 결합하여 4주 동안 8시간 주기로 1시간씩 수중에서 간헐적으로 작동시켰다. 양액(대조구), 플라즈마 활성수(4.2kV, 5.7kV)를 사용하여 온실에서 재배하였으며 이후 수확하여 생육조사 및 기능성 물질 분석을 실시하였다. 플라즈마 활성수 처리 기간 동안 발생되는 활성산소종 중에서 O₃로 인하여 플라즈마 발생 장치에 근접한 개체일수록갈색 반점 및 괴사현상이 나타났으며, 생육조사를 실시한 결과 유의적 차이가 나타나지 않았다. 기능성 물질 분석 결과 상추 지상부의 rutin과 총 페놀 함량은 플라즈마수보다 높았지만, epicatechin의 경우 플라즈마수 처리에서 함량이 더 많았다. 근권부에서 측정된 이차대사산물인 rutin, epicatechin, quercetin 및 총 페놀 함량은 대조구보다 플라즈마수 처리구에서 유의하게 높았다. 이러한 결과는 플라즈마수 처리 시간동안 수중에 오존과 같은 활성산소종으로 인해 지상부 생육이 잘 이루어지지 못했으나, 근권 영역에서는 이차대사산물이 크게 증가하였다. 향후 간헐적인 플라즈마 활성수 생성에 따른 생리 장해를 극복하고 뿌리채소의 수경재배 시스템에 적용하여 이차대사산물을 증가시키기 위한 본 기술의 도입이 필요하다.

• 한국작물학회지
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• 제41권spc1호
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• pp.123-144
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• 1996

This review deals briefly with the various medicinal components(mainly saikosaponins), their biological activities and the variation of their contents by different cultivation environment and plant parts in Bupleurum species. Bupleuri radix, a crude drug, is the root of Bupleurum falcatum L. (Korea, Japan), B. chinense(China), and their related species (Umbelliferae). There are over 120 species in Bupleurum genus throughout world, mainly Asian area, and over 5 species in Korea, investigated up to now. These plants contain many physiological active compounds and the principal components are saikosaponins. Major activities of this crude drug and saikosaponins are the anti-inflammatory and antihepatotoxic activities. Saikosaponins and their derivatives in Bupleurum spp. have been chemically studied, isolated and identified over 70 compounds in over 50 species. Other components, physiologically active ones, also have been investigated, which are the groups of lignan, flavonoid, essential oil, polyacetylene, polysaccharide, etc. Saikosaponins belong to the group of triterpenoid saponin chemotaxonomically and occur the accumulation and turnover in plant tissues through secondary metabolism, mevalonic acid pathway. The contents and kinds of saikosaponins and other components in Bupleurum spp. plants are various due to different species and growing environments, as the plant growth characters and yield are various. Most of medicinal plants as well as Bupleurum species are very useful as agricultural products and traditional medicines, and also are very valuable as genetic resources and natural products. So we need to collect, evaluate, preserve, and utilize various medicinal plants, and also to under-stand secondary metabolism and improve the breeding and cultivation techniques for the safe production of crude drugs with high quality and yielding.