• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.1
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• pp.38-43
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• 2003

Immature and mature embryos of 18 Korean wheat genotypes were cultured in vitro to develop an efficient method of callus formation and plant regeneration, and to compare the responses of both embryo cultures. Immature and mature embryos were placed on a solid agar medium containing the MS salts and vitamins, 30g/l maltose, 2 mg/l 2,4-dichlorophenoxyacetic acid (2,4-D), and amino acids. The developed calli were maintained on regeneration medium containing MS salts and B5 vitamins, 20 g/l sucrose, and the combination of two plant growth regulators, 6-benzylaminopurine (BAP) and indole-3-acetic acid (IAA). Immature embryos in most genotypes showed high efficiency of callus induction except three genotypes; Eunpamil, Chunggemil, and Namhaemil, and significant differences among the genotypes. Plant regeneration of calli induced from immature embryos showed high efficiency in Geurumil (56.5%), Tapdongmil (50.5%), Gobunmil (45.5%), and Urimil(42.2%). The analysis of variance showed significant differences for regeneration frequency among the genotypes. Mature embryos showed low callus induction frequency compared with that in immature embryos, and significant differences among the genotypes. Plant regeneration of calli induced from mature embryos showed high efficiency in Keumkangmil (33.33%), Tapdongmil(28.13%), and Geurumil (27.78%). The analysis of variance showed significant differences for plant regeneration frequency among the genotypes.

• Plant Biotechnology Reports
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• v.4 no.3
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• pp.229-235
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• 2010

In this study, we established an in vitro regeneration system to maximize the recovery of leafy perilla (Perilla frutescens L. Britton) plantlets as part of developing a molecular biotechnology-based metabolic engineering program for this crop plant. Hypocotyl segments including the apical buds were used as explants for the direct production of shoots without an interim callus phase. The number of shoots produced from the apical buds peaked within 3-4 weeks, and the shoots were subsequently cultured on Murashige and Skoog (MS) media supplemented with 2 mg $1^{-1}$ benzylaminopurine (BA). Spontaneous rhizogenesis was observed after 7-10 days of culture on MS media without hormonal additives. The rooted shoots developed into normal plants in soil after hardening on distilled water for 3-4 days. The average plantlet regeneration frequency was higher for the apical buds (64.33%) than for the top (15.66%), middle (4%), and basal (1.33%) segments of the hypocotyls. This regeneration system demonstrates a capacity for high-frequency plantlet recovery and thus should be considered for use in the genetic manipulation of leafy perilla.

• Journal of The Korean Society of Grassland and Forage Science
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• v.20 no.1
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• pp.7-12
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• 2000

This study was carried out to improve the ability of embryo formation and the efficiency of plant regeneration from suspension cultured cells of seed derived calli of orchardgrass (Dactylis glomerata L.). The frequency of formation of round cell and cell colonies was highest at 50 days after suspension culture in $N_6$ medium supplemented with $4\;g/{\ell}$ casein hydrolysate (CH), $20\;g/{\ell}$ sucrose and $30\;g/{\ell}$ sorbitol. The highest frequency of plant regeneration and somatic embryo formation was obtained from suspension cultured cells of 60 days. Addition of CH ($4\;g/{\ell}$) in suspension culture medium gave the highest frequency of embryo formation (39.6%) and plant regeneration (73.0%).

• Journal of The Korean Society of Grassland and Forage Science
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• v.26 no.4
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• pp.187-192
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• 2006

In order to investigate the effects of genetic variations of orchardgrass in tissue culture response, calli were induced from mature seeds of eight varieties, 'Hapsung 2', '93E', 'Amba', 'Ambassdor', 'Frode', 'Frontier', 'Potomac' and 'Roughrider', and plant regeneration frequency was compared. Significant differences were observed among the varieties in both callus induction and plant regeneration. Callus induction rate of viable seeds varied from 24.3% to 71.7%. Plant regeneration frequency ranged from 76.6% to 29.7%. 'Roughrider' varieties showed higher regenerability with the frequency of 76.6%. These results can be used not only to provide additional improvements in the plant regeneration frequency from transgenic callus, but also useful for molecular breeding of orchardgrass through genetic transformation.

• Korean Journal of Microbiology
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• v.24 no.1
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• pp.24-31
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• 1986

The optimal conditions for the formation and the regeneration of Pseudomonas spheroplast were measured. Pseudomonas spp. cells were transformed to spheroplasts from 99.0% to 99.9% by treatment of $100{\mu}g/ml$ lysozyme and 10mM EDTA at room temperature. The optimal pH for the spheroplast formation was pH 8.0. Magnecium chloride, calcium chloride and streptomycin were effective on the stabilization of Pseudomonas spheroplast, while $Mg^+\;and\;Na^+$ ions were effective on the formation of Pseudonomas spheroplast. Rich Regeneration Medium was used for the regeneration of Pseudonomas spheroplast. To improve regeneration frequency, Bovin Serum Albumine and cationic ions were added to the spheroplast dilution beffer and regeneration environment respectively. Treatment of 20mM calcium chloride in ehr Rich Regeneration Medium could improve the yield of regenerants as much as 28-fold. Treatment of 1% Bovin Serum Albumine in the spgeroplast formation and dilution buffer increased the yield of regenerants to 10-fold. Also, the regeneration frequency was improved to 14-fold shen Rich Regeneration Meidum containing 0.5% Gelatin was used for regeneration as well as 1% Bovin Serum Albumine.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.43 no.4
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• pp.449-458
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• 2023

As an adsorption technology for dissolved organic matter, the adsorption capacity of granular activated carbon, GAC, can be applied, but activated carbon whose adsorption capacity is significantly reduced by use is inevitably replaced or regenerated. However, due to the economics of replacement cost, thermal regeneration method is used commercially, but high energy cost and loss of activated carbon occur under high temperature conditions above 800℃. In this study, the Sono-Fenton method, a multi-oxidation technology that combines Fenton oxidation and ultrasonic oxidation, was applied to improve the regeneration efficiency of spent GAC used to treat dissolved organic matter in combined sewer overflows (CSOs), and the regeneration efficiency of spent GAC by oxidant and ultrasonic frequency was investigated. In the applied Sono-Fenton treatment, the highest regeneration efficiency of 68.5% was obtained under the regeneration conditions of Fe²⁺ 10 mmol/L, H₂O₂ concentration 1,000 mmol/L, ultrasonic treatment time of 120 min, and ultrasonic frequency of 40 kHz. And similar efficiency was also obtained at 750 kHz, while ultrasonic waves of other frequencies had poor regeneration efficiency, and the magnitude of frequency and GAC regeneration efficiency did not show a linear relationship. In the case of continuous operation of the GAC adsorption tower with CSOs prepared by diluting raw sewage, about 700 hours of operation without regeneration was possible, and as a result of applying one Sono-Fenton treatment, 40-70% COD_cr removal efficiency was obtained during a total of 1,000 hours of GAC adsorption operation.

• Microbiology and Biotechnology Letters
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• v.16 no.4
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• pp.303-309
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• 1988

In order to establish the process of interspecific protoplast fusion of the genus Cellulomonas capable of utilizing of cellulose, C. flavigena NCIB 12901 and Cellulomonas sp. CSI-1, the optimum conditions for the regeneration and fusion were examined. The condition of suitable osmotic stabilizer for the protoplast regeneration of C. flavigena was established by using 0.4M sorbitol. And then, by addition of 3% po]yvinyl pyrrolidone (PVP) to cell wall regeneration medium, regeneration frequency was increased 3 times higher than that without PVP addition. The optimum conditions for the interspecific protoplast fusion between auxotrophic and antibiotics resistant mutants were obtained with 40%(W/V) of PEG (polyethylene glycol) 6000 as the fusogenic agent and 25mM of CaCl$_2$on treating time for 15 min. The fusion frequency between mutants was from 2.0$\times$10$^{-4}$ to 4.0$\times$10$^{-4}$ under the optimum conditions. The fusants were confirmed to revert from protoplast to cells of rod type during regeneration process and the aggregation of protoplast by PEG was observed. Also the progress of fusion was observed by scanning electron microscopy, Many isolated fusants were shown to be complement clones of both parents which occured at a high frequency among the isolated clones.

• Asia-Pacific Journal of Business
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• v.13 no.4
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• pp.1-10
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• 2022

Purpose - Despite the emergence of such destination regeneration as a key factor in urban tourism, little research was carried out on destination regeneration, especially on the impact of destination regeneration on revisit intention. The purpose of this study is to investigate the relationship between destination regeneration and revisit intention with moderating role of the destination image. Design/Methodology/Approach - Data were collected from tourists who visited the destination, after which a total of 250 usable surveys were analyzed. In order to examine the data, we used frequency analysis, exploratory factor analysis, regression analysis by using SPSS 25.0. Findings - Based on the results, first, there is a positive relationship between destination regeneration and revisit intention. In addition, there are significant moderating effects of destination image between destination regeneration and revisit intention. Research Implications or Originality - Those significant findings could contribute to destination development from destination regeneration and revisit intention.

• Journal of Plant Biotechnology
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• v.36 no.3
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• pp.236-243
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• 2009

The halophyte Leymus chinensis (Trin.) is a perennial rhizome grass (tribe Gramineae) that is widely distributed throughout China, Mongolia and Siberia. This study was conducted to investigate an optimal condition for plant regeneration from mature seeds, leaf base segments, and root segments in L. chinensis. Plant growth regulators affecting embryogenic callus induction and plant regeneration were investigated by four-factor-three-level [L9 (34)] orthogonal test in this study. The effects of explants types (mature seeds, leaf base segments and root segments), callus types, medium types were examined in this study. Wild type (WT) and Jisheng No. 1 plants (JS) were used for primary callus induction. A clear explants difference was seen during callus induction; mature seeds were considered as the preferred explants; and the highest frequency of callus induction was obtained in Medium 6 using mature seeds as explants in WT. Plant regeneration ability was evaluated by frequencies of green callus forming, shooting, rooting, and shooting with roots. Effect of α-naphthalene acetic acid (NAA) on shoot regeneration was remarkable with the highest frequency of 70.8% in WT after 2-month culture. The medium with 0.2- 0.5 mg/L NAA was found to have the highest shoot induction. All regenerated shoots were successfully rooted when transferred on half-strength Murashige and Skoog (MS) basal medium. The acclimatized plantlets were grown to mature with flowering and seeds setting in green house conditions.

• Journal of Plant Biotechnology
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• v.36 no.4
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• pp.403-406
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• 2009

This study was conducted to develop an effective production of callus induction and plant regeneration system for garlic transformation. The best callus production occurred on in vitro root segment initially cultured on MS medium with 1.0 mg/L 2,4-D and 0.2 mg/L IAA in both ‘Danyang' and ‘Euseong'. The frequency of callus formation were 81.2% ‘Danyang' and 76.1% ‘Euseong'. Eight weeks after callus induction, callus lines were transferred to regeneration medium during 7 weeks. The best shoot regeneration medium was MS supplemented with 5 mg/L Kinetin and 1 mg/L NAA for ‘Danyang' and MS supplemented with 10 mg/L BAP for ‘Euseong'. The frequency of shoot regeneration were 51.5% ‘Danyang' and 56.6% ‘Euseong' The plantlets were acclimatized and transferred to the greenhouse with almost survival. This in vitro regeneration system should be useful for garlic transformation.