• Plant Biotechnology Reports
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• v.3 no.2
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• pp.139-145
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• 2009

DNA methylation is known to play an important role in the regulation of gene expression in eukaryotes. In this study, we isolated NtMET1 from Nicotiana tabacum cv. Havana (SR1) and obtain transgenic plants that reduced MET1 expression level with the double-strand RNA (dsRNA) MET1 gene. Transgenic tobacco plants showed dwarf and abnormal flower development when compared with the wild type. Using methylation-sensitive amplified polymorphism (MSAP) analysis, the patterns of cytosine methylation in transformed plants and the wild type were compared. MseI/HpaII selection primers showed an interesting polymorphism, and 153 DNA bands of interest were detected. Among these, 30 selective fragments were sequenced and analyzed with a BLAST search by successful MSAP modifications. The homology search showed that the transposons and tandem repeated sequences were related to the phenotypes. These results suggested that the decreased degree of methylation by dsRNA strategy caused abnormal growth and development in N. tabacum.

• Journal of Ginseng Research
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• v.20 no.3
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• pp.269-273
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• 1996

We investigated the effects of ginseng glycosides and their aglycones on processes of single ion channel formation and channel properties. The glycosides, Rg, and Rb, , and their aglycones, 20-(S)-protopanaxatriol (PT) and 20-(S)-protopanaxadiol (PD) increased the membrane permeability for ions. PT, PD, Rg1, and Rb1; at concentrations of 0.5, 3.0, 10.0 and 30.0 $\mu\textrm{g}$/ml respectively; Induced single ion channel fluctuations with the life times in the range of 0.1~1005 in open states and conductances from 5 to 30 pS in 1 M KCI. At high concentrations of these substances, rapid fluctuations of transmembrane ion current with amplitude from hundred pS to dozen nS were observed. Against other substances, ginsenoside Rbl began to increase the membrane conductance at concentration of about 60 $\mu\textrm{g}$/ml without fluctuation of single ion channel. Membranes treated with PT, PD, Rg1 and Rb1 are more permeable to K+, than to Cl while zero current membrane potentials with 10 gradients of KCI were 12, 16, 8, 25 mV respectively. Key words : Membrane conductance, single ion channel, ginsenosides.

• Journal of the Korean Society of Tobacco Science
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• v.29 no.2
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• pp.66-73
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• 2007

This study was carried out to investigate the changes of curing condition on microclimate of temperature, relative humidity during curing process of burley tobacco leaves. The developed facility, ridge opening type was designed to open the central top roof. The air-cured variety, (N. tabacum cv KB111) was normally grown at the Eumseong tobacco experimental station in 2007. Mean daily temperature of $3^{\circ}C$ in ridge opening type curing facility was lower than that of conventional, whereas mean daily relative humidity of 12.6 % RH was lower in conventional curing facility for the entire stage of curing. The frequency distribution of optimal air temperature at daytime was higher 37.5 % in ridge opening type curing facility than that of conventional, while that of optimal relative humidity was lower 8.2 %. In the ridge opening type curing facility, the excessive drying leaves were low, however the price per kilogram was high. These results suggest that the new developed curing facility may be applied to improved microclimate inside the curing facility for curing burley.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.16
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• pp.7007-7009
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• 2015

Background: Tobacco use in various forms, including with Areca nut, causes several potentially malignant disorders. Many lesions may transform into oral squamous cell carcinoma. Although patients may be aware of the hazards of tobacco habits, the lesions by themselves are insidious in nature resulting in failure of patients to present to general dentists/specialists at early stages. Our aim was to study the types of habits prevalent in the region of Rourkela in Orissa and to assess the insidious nature of the lesions associated with these habits. Not many studies have been done from this part of India. Materials and Methods: A camp was conducted for habitual users of tobacco and its products, Areca nut and other mixed habit users. A thorough history was taken of the type, duration and frequency of habits, symptoms of patients along with clinical examination by a single examiner. The data was entered in detail into an excel sheet and analysed. Results: 54.7% had lesions and 60.9 % of them were asymptomatic and rest had mild burning sensation while eating. There was a very low awareness of the presence of lesions among the patients. Conclusions: There is a need to spread the awareness of the ill effects of the tobacco and other associated habits far and wide and more importantly educate the general public on the appearance of associated lesions as these are almost always insidious in nature. The patients can self-examine, detect lesions early when present and approach the dentist at the earliest opportunity.

• Journal of the Korean Society of Tobacco Science
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• v.35 no.1
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• pp.7-12
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• 2013

A Solid-phase micro extraction(SPME) was evaluated as a tool for headspace sampling of tobacco samples. Several experimental parameters (sampling temperature, pH, and type of SPME fibers) were optimized to improve sampling efficiency in two aspects ; maximum adsorption and selective adsorption of volatile organic acids onto SPME fibers. Among four types of SPME fibers such as PDMS(Polydimethylsiloxane), PA(Polyacrylate), Car/PDMS (Carboxen/Polydimethylsiioxane) and PDMS/DVB(Polydimethylsiioxane/Divinylbenzene) which were investigated to determine the selectivity and adsorption efficiency. A variety of tobacco samples such as flue cured, burley and oriental were used in this study. The effect of these parameters was often dominated by the physical and chemical nature (volatility, polarity) of target compounds. This method allowed us to make important improvements in selectivity and sensitivity. The Car/PDMS fiber was shown to be the most efficient at extracting the 10 selected volatile organic acids. The parameters were optimized: $80^{\circ}C$ adsorption temperature, 30 min of adsorption time, $240^{\circ}C$ desorption temperature, 1 min of adsorption time.

• Journal of the Korean Society of Tobacco Science
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• v.16 no.1
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• pp.69-75
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• 1994

A new flue - cured tobacco variety KF113 was developed by Nicotiana africana method from a cross of NC82 and Coker 347 at the Suwon Experiment Station. It was tested in the 0fficial Variety Test in 1991-1992 and the flue - cured Regional Farm Test in 1992. KFl13 flowers 4 days later than WC82 (standard variety in Korea) and its harvestable leaves are 2 more than those of NC82. The leaf type and shape of KFl13 resembles Coker 347. It has high resistance to bacterial wilt (Pseudomonas solanacearum) and black shank (Phytophthora parasitica var. nicotianae), and is susceptible to tobacco mosaic virus. It should adapt well to the flue - cured production area and can reduce premature flowering under unfavorable weather conditions. Yield of KFl13 is 5% higher than that of NC82, and nearly equal in value per kg compare with NC82. This variety met acceptable standards for chemical and physical characteristics of cured leaf and for smoking taste evaluated by panel members in Korea Ginseng & Tobacco Research Institute.

• Journal of the Korean Society of Tobacco Science
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• v.32 no.2
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• pp.77-87
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• 2010

Traditional simultaneous distillation extraction(SDE) and solid-phase micro extraction(SPME) methods using GC/MS were compared for their effectiveness in the extraction of volatile flavor compounds from different tobacco leaves types(flue-cured, burley, oriental). The major volatile flavor compounds of flue-cured and burley tobacco were similar such as neophytadiene, solanone, megastigmatrienone isomers, ${\beta}$-damascenone and ${\beta}$-ionone. On the other hand, volatile flavor compounds such as norambreinolide, sclareolide were specifically identified in oriental tobacco. Each method was used to evaluate the responses of some analytes from real samples and standards in order to provide sensitivity comparisons between two techniques. Among three types of SPME fibers such as PDMS(Polydimethylsiloxane), PA(Polyacrylate) and PDMS/DVB (Polydimethylsiloxane/Divinylbenzene) which were investigated to determine the selectivity and adsorption efficiency, PDMS/DVB fiber was selected for the extractions of the volatile flavor compounds due to its effectiveness. The qualitative analysis showed that the total amount of volatile flavor compounds in SDE method(130 species) was much more than that in SPME method(85 species). SPME method was more efficient for all the highly volatile compounds than SDE method, but on the other hand, low-volatile compounds such as fatty acids or high-molecular hydrocabons were detected in SDE method. SPME method based on a short-time sampling can be adjusted to favor a selected group compounds in tobacco. Furthermore this results could be used to estimate the aroma characteristics of cigarette blending by using a different type of tobacco with more effectiveness and convenience.

• Journal of Plant Biotechnology
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• v.40 no.1
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• pp.49-54
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• 2013

C3HC4-type RING zinc finger proteins essential in the regulation of plant processes, including responses to abiotic stresses. We previously isolated and examined the C3HC4-type RING zinc finger protein (BrRZFP1) from Brassica rapa under abiotic stresses. To elucidate the role of the BrRZFP1 transcription factor in gene regulation, we transformed tobacco plants with the BrRZFP1 gene. Plants were regenerated from 82 independently transformed callus lines of tobacco and analysed for transgene expression. Transgene integration and expression was confirmed by Southern and RT-PCR analyses, respectively. T2 plants displayed more tolerance to the bacterial pathogens Pectobacterium carotovorum and Ralstonia solanacearum, and the tolerance levels were correlated with BrRZFP1 expression levels. These results suggest that the transcription factor BrRZFP1 is an important determinant of stress response in plants and its overexpression in plants could increase biotic stress resistance.

• Journal of Bio-Environment Control
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• v.11 no.3
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• pp.139-143
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• 2002

Cotton Glutathione S-Transferase (GST: EC 2.5.1.18) was cloned and overexpressed in tobacco (Nicotiana tabacum) plants. Northern blot analysis confirmed the successful transformation of cotton gst gene in tobacco plant. Type I and Type ll transcript patterns were identified in transgenic tobacco plants and only Type I transcripts were discussed in this paper, The activity of GST in the type II transgenic plants was about 1.5-fold higher than those of the wild type and non-expresser by using 1-chloro-2,4-dinitrobenzene (CDNB) and reduced glutathione as the substrate. The expression of cotton GST in tobacco plants proved that Gh-5 could be translated into functional protein. Type II transgenic plants produced functional GST in the cells. The effects of cotton GST in the seedlings was evaluated by growing the control and transgenic seedlings at $15^{\circ}C$ in the growth chamber in the light. Overexpressors were grown well compared to the control plants (non-expressors). lo test far tolerance to salinity, seeds of Gh-5 overexpressors and the wild type Xanthi seedlings were grown at 0, 50, 100, 150, and 200 mM NaCl solution. Gh-5 transgenic seedlings showed higher growth rate over control seedlings on 50 and 100 mM NaCl solution. There was no difference in growth rate at 150 and 200mM NaCl concentration.

• Journal of the Korean Society of Tobacco Science
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• v.9 no.1
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• pp.45-55
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• 1987

For some basic information in tobacco breeding, the modes of inheritance and heritabilities for the twelve agronomic and chemical characters were estimated in the study of eight varieties partial diallel set. Additive gene actions were significant for all characters except total nitrogen content and dominance gene effects were also significant for all characters. Yield, number of leaves per plant, leaf length and leaf shape index were inherited as partial dominance, and overdominance was detected for plant height, stem diameter, internode length, total alkaloid, total nitrogen and total sugar content. Dominant gene showed increasing effects in yield, plant height, stem diameter, internode length, leaf width and total sugar content, but showed decreasing effects in the other characters. The broad heritability was very high for all characters. and the narrow heritability was high in days to flower and yield, but low in internode length, total alkaloid, total nitrogen and total sugar content.