• Horticultural Science & Technology
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• v.29 no.5
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• pp.467-473
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• 2011

Flavonoid are large group of the polyphenolic compounds which are distinguished by an aromatic or phenolic ring structure and the phenolic compounds are induced by microbial infection, ultraviolet radiation, temperature and chemical stress. They are known for their antioxidant activity, anti-allergic, anti-inflammatory, anti-microbial and anti-cancer activities. In this study, changes in flavonoid content were investigated using heterologous chalcone isomerase (CHI) expression system. Also, phenolic compounds level was measured to examine the relation between flavonoids and phenols contents. Explants of lettuce (Lactuca sativa L.) were transformed with Agrobacterium tumefaciens LBA 4404 strain containing pFLH-CHI (derived from pPZP2Ha3) vector constructed with CHI gene from Brassica rapa. The putative transgenic plants were confirmed by genomic DNA PCR analysis. Also the transcription levels of the gene were analyzed by semi-quantitative RT-PCR with gene specific primers. The total flavonoid contents were increased at $T_0$ and $T_1$ generations over 1.4 and 4.0 fold, respectively. Total phenol contents also increased at $T_1$ generation. These results indicate that CHI gene plays an important role to regulate the accumulation of flavonoids and its component changes.

• Journal of Plant Biotechnology
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• v.3 no.3
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• pp.135-140
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• 2001

An Agrobacterium tumefaciens LBA4404 (harboring antisense OMT gene)-mediated transformation method has been developed for poplar (P.nigra x maximowiczii) using prolonging co-cultivation time. Explants on LT (longterm) were induced transgenic calli one month earlier than those from ST (short-term) co-cultivation and remained healthier on LT than ST. With this approach, LT method reduced time to produce transgenic calli. Shoots were successfully regenerated from transgenic calli on SIM (Shoot Induction Medium) and rooted well on the basal medium spontaneously. The presence of antisense OMT gene was verified both by PCR and Southern analysis. Each transgenic poplar was phenotypically indishtinguishable when compared with controls for their growth pattern, leaf morphologies and xylem coloration.

• Journal of KIISE:Software and Applications
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• v.30 no.3_4
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• pp.372-378
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• 2003

Limitations on the linear discriminant analysis (LDA) for face rerognition, such as the loss of generalization and the computational infeasibility, are addressed and illustrated for a small number of samples. The principal component analysis (PCA) followed by the LDA mapping may be an alternative that ran overcome these limitations. We also show that any schemes based on either mappings or template matching are vulnerable to image variations due to rotation, translation, facial expressions, or local illumination conditions. This entails the importance of a proper preprocessing that can compensate for such variations. A simple template matching, when combined with the geometrically correlated feature-based detection as a preprocessing, is shown to outperform mapping techniques in terms of both the accuracy and the robustness to image variations.

• The Journal of Information Systems
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• v.28 no.4
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• pp.313-332
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• 2019

Purpose As mobile devices are in widespread use and location-based mobile advertising has grown rapidly in recent years, there exists a sharp increase among researchers as well as practitioners in the interest in the determinants of user's attitudes towards location-based Mobile advertising. The purpose of the research is to understand the predictors of attitudes towards location-based Mobile advertising and of the relationship between attitudes and behavioral intention. Design/methodology/approach To this end, we have conducted an online survey using 412 users who have the prior experience of viewing location-based advertising via their mobile devices. We excluded 31 invalid responses and performed an empirical analysis based on 381 responses. Findings The findings indicate that all the factors but 'perceived enjoyment' each have a significant, positive relationship with consumer attitudes towards location-based Mobile advertising. Furthermore, advertising attitude is positively associated with behavioral intention. We provide implications and future research directions based the research findings.

• Journal of Plant Biotechnology
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• v.30 no.3
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• pp.269-273
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• 2003

In order to develop an efficient micropropagation protocal for Eucalyptus pellita, on in vitro culture system has been was established by inducing axillary buds from greenhouse stock materials. Among 6different media tested, DKW medium was the best ot induce bast induce both shoot proliferation and growth. Average number of proliferated shoots of 403per explant was obtained at the concentration of 0.1mg/LBA. Most of the stem materials excreted phenolic compounds at the proximal part of the explant and caused darking of the media. Therefore, it was necessary to transfer frequently to a fresh medium and/or to add activated charcoal at the concentration of 0.02％(w/v). Generally on vitro roots were formed easily on 1/2DKW medium with NAA treatment. All the explants rooted at the medium containing 0.2mg/L NAA and displayed vigorous root growth in vitro culture conditions. After transferred to an artificial soil mixture (peatmoss: vermiculrite: perlite, 1:1:1, v/v/v) in the greenhouse, most rooted plantlets survived well without any morphological abnormalities. The results show that the species can be micropropagated effectively by the application of axillary bud culture system.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.5
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• pp.375-379
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• 2001

Transgenic plants from hypocotyl segments of buckwheat were produced with the Agrobacterium strain LBA4404 harboring the binary vector pBI121 containing chimeric genes of neomycin phosphotransferase II (npt II) and $\beta$-glucuronidase (gus). Two weeks after co-cultivation with Agrobacterium, most of the hypocotyl segments gradually became brown and died on the selection medium containing 100mg/$\ell$ of kanamycin. Plants regenerated from the hypocotyl explants grown on selection medium were GUS-positive in the leaf, stem and vascular tissues by histochemical assay, and varied in gus activity (440-2568 pmol, 4-MU/mg protein) by fluorimetry. The plants showing GUS activity were confirmed of containing GUS and NPT-II genes by polymerase chain reaction (PCR). Within 3 months, transgenic buckwheat plants were able to obtained from the hypocotyl segments.

• Journal of Plant Biotechnology
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• v.5 no.1
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• pp.19-23
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• 2003

The Ac (activator) which is one of the well-characterized transposable elements from maize was examined for its transposition possibility to the heterologous plant (P.nigra x maximowiczii) genome via Agrobacterium tumefacience (LBA4404) mediated transformation system. A number of transgenic plants were successfully recovered after 30 weeks by amount reduction from 50 to 15 g/$m\ell$ kanamycin for in vitro selection to minimize phytotoxic effects and to increase callus growth and regeneration efficiency. Among transgenic plants, 62 out of 106 transgenic poplars (58.5%) showed abnormal phenotypes such as severe serrated leaves and light leaf coloration. Indigo staining with X-gluc proved indirectly the restoration of Gus enzyme function and the presence of Ac in poplar genome by PCR. Southern analysis indicated the transposition and existence of Ac element in poplar genomes. In this research, an Agrobacterium-mediated transformation system in poplar species was developed and identified that Ac derived from maize can be excised and trans posed into other poplar genomes.

• Journal of Plant Biotechnology
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• v.36 no.4
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• pp.366-372
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• 2009

This study was conducted to develop new lines expressing the characteristic of early flowering by introducing MdMADS2 gene in chrysanthemum (Dendranthema grandiflorum (Ramat.) Kitamura) ‘Zinba'. Transformation of chrysanthemum was conducted by Agrobacterium tumefaciens LBA4404 harboring the binary vector containing MdMADS2 controlled by double CaMV 35S promoters. Ninety three shoots were regenerated from 1,463 leaf segment explants cultured on the first selection medium (MS basal salts + 1.0 mg/L BA + 0.5 mg/L IAA + 10 mg/L kanamycin + 400 mg/L cefotaxime, pH 5.8) after co-cultivation, and 20 out of the 93 shoots rooted on the second selection medium containing 20 mg/L kanamycin and 400 mg/L cefotaxime. Many escapes (98.6%) were removed on the selection stage for rooting. Nineteen lines were confirmed as transgenic plant with transgene by PCR analysis. Six transgenic plants flowered 2-11 days earlier than non-transgenic plant without big change of phenotype, and especially, 3 (Mo-7, Mo-11, Mo-17) out of 6 transgenic lines showed a significant reduction in days to flowering compared to non-transgenic plant. Introduction and expression of MdMADS2 gene in them were confirmed by Southern and real-time PCR analyses, respectively.

• Journal of The Korean Society of Grassland and Forage Science
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• v.18 no.1
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• pp.69-76
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• 1998

This study was conducted to construct of the transgenic plants wliich are resistant to oxidative stresses including ozone with B. mpestris cytosolic glutathione reductase cDNA using the binary vector system of Agrobacterium tumefaciens. The 1.8kb B. campestris cytosolic GR cDNA was subcloned into the unique Sma I site of the plant transformation vector pBKSI- I, downstream of the constitutive CaMV 35s promoter and upstream of the nos termination sequence, in place of the uidA (GUS) reporter gene. The resulting plant transformation vector, pBKS-GRI, was introduced into A. tumefaciens LBA4404 by two cycles of tkeze-thaw method. The B. nqus cotyledonary petioles were transformed by the Agrubaferium harboring pBKS-GRI. Transformed shoots were induced and selected on regeneration medium supplemented with kanarnycin. The shoot formation was increased remarkably by addition of Ag$NO_3$, in MS media. The transgenic plants were analyzed for the presence of the B. campestris GR gene by Southern blot analysis and it was confirmed that a foregin gene was stably integrated into the genomes of B. nqus plants.

• Plant Resources
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• v.6 no.2
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• pp.108-113
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• 2003

This study was carried out to obtain basic information for possibility of oral vaccine in carrot using Agrobacteruim -mediated transformation system. The epitope region of porcine epidemic diarrhea virus (PEDV) spike gene which is classified as a member of the Coronaviridae and causes an acute enteritis in pigs was successfully expressed in carrot (Daucus carota) using the Agrobacterium-mediated transformation system. Hypocotyl segments of in vitro germinated plantlets were infected with Agrobacteriun tumefaciens LBA 4404 harboring PEDV spike gene. Embryogenic callus (EC) was induced on MS selection medium with 1 mg/L 2,4-D, 50 mg/L kanamycin and 300 mg/L cefotaxime after 45 days of culture. Subcultured ECs on MS selection medium without 2,4-D were converted to somatic embryos (SE) of various stage; globular, heart and torpedo stage. Putative transgenic embryos were selected on MS medium with 50 mg/L kanamycin and 300 mg/L cefotaxime. Regenerated plantlets from transformed SE were induced on MS medium containing 50 mg/L kanamycin after 30 days of culture. Genomic PCR confirmed the integration of PEDV spike gene into nuclear genome of carrot and northern blot analysis demonstrated the expression of PEDV spike gene in transgenic carrot.