• Journal of Periodontal and Implant Science
• /
• v.31 no.4
• /
• pp.823-832
• /
• 2001

Periodontal therapy has dealt primarily with attempts at arresting progression of disease, however, more recent techniques have focused on regenerating the periodontal ligament having the capacity to regenerate the periodontium. The effect of chitosan(poly-N-acetyl glucosaminoglycan), a carbohydrate biopolymer extracted from chitin, on periodontal ligament regeneration is of particular interest. The purpose of this study was to evaluate the effect of chitosan on the human periodontal ligament fibroblasts(hPDLFs) in vitro, with special focus on their proliferative properties by M'IT assay, the synthesis of type I collagen by reverse transcription-polymerase chain reaction(RT-PCR) and the activity of alkaline phosphatase(ALP). Fibroblast populations were obtained from individuals with a healthy periodontium and cultured with ${\alpha}MEM$ as the control group. The experimental groups were cultured with chitosan in concentration of 0.01,0.1, 1,2mg/ml. The results are as follows; 1. Chitosan-induced proliferative responses of hPDLFs reached a plateau at the concentration of O.lmg/ml(p<0.05). 2. When hPDLFs were stimulated with 0.lmg/ml chitosan, mRNA expression of type I collagen was up-regulated. 3. When hPDLFs were stimulated with 0.lmg/ml chitosan, ALP activity was significantly up-regulated(p<0.05). In summary, chitosan(0.lmg/ml) enhanced the type I collagen synthesis in the early stage, and afterwards, facilitated differentiation into osteogenic cells. The results of this in vitro experiment suggest that chitosan potentiates the differentiation of osteoprogenitor cells and may facilitate the formation of bone.

• Journal of Plant Biotechnology
• /
• v.35 no.3
• /
• pp.223-228
• /
• 2008

This study was conducted to investigate an optimal condition for shoot proliferation and regenerate shoots from in vitro leaflet and embryogenic calli from in vitro roots in rose. The effect of BAP on shoot proliferation was somewhat different depending upon genotypes or gelling agents. Leaflets with petiole cut from donor shoots which had been cultured in MS medium supplemented with 0.1 $mg{\cdot}L^{-1}$ NAA for six weeks was effective for regeneration of adventitious buds(ABs) as well as shoot elongation of Rosa hybrida cv. Sweet Pink. Culturing seven leaflet explants per petri plate($100mm{\times}15mm$) was effective for regeneration of ABs. Embryogenesis was shown in the calli induced from roots of Rosa hybrida cv. Sweet Pink cultured in the SH medium supplemented with 11 $mg{\cdot}L^{-1}$ 2, 4-D for four weeks. Color of calli induced from roots was yellow although their color was a little different as type of basal medium.

• Plant Resources
• /
• v.2 no.1
• /
• pp.16-21
• /
• 1999

An efficient regeneration system was established by using in vitro plantlets of germinated seedlings from different cultivars of lettuce (Lactuca sativa cv. Chongchima, Chongchuckmyun, Jeokchima, Jeokchuckmyun). Shoot formation were observed from all cultivars on MS medium supplemented with 0.1 mg/L NAA and 0.5 mg/L BA. In all cultivars, when cotyledon was cultured, the number of shoot per explant was more greater than that hypocotyl and leaf disc were cultured. Shoot formation rate (91.7%) was high in a cotyledon culture of cultivar, Chongchukmyun. The growth of multiple shoots derived from the cultivar, Chongchukmyun, was most effective on medium containing 0.5 mg/L BA and 1.0 mg/L GA$_3$. When shoots were transferred on MS medium without plant growth regulators, roots were effectively differentiated. Rooted plantlets were acclimated on pots for further propagation.

• Journal of Life Science
• /
• v.14 no.5
• /
• pp.855-858
• /
• 2004

The experiment was conducted to investigate optimal condition for callus induction and plant regeneration for transformation system of gerbera. Callus induction was more effective in 'white day' then other two cultivar 'Songsongee' and 'Love Song' The optimized plant growth regulators concentration on callus induction, was MS basal medium with NAA 0.1 mg/L＋ TDZ 0.5 mg/L. The optimized plant growth regulators concentration on plant regeneration, which was used MS basal medium was IAA 1.0 mg/L ＋ BA 1.0 mg/L ＋ Zeatin 0.1 mg/L. The optimized petiole age for more effective plant regeneration was 32 days petiole after in vitro subculture and MS basal medium strength was 1/2 MS strength.

• Horticultural Science & Technology
• /
• v.32 no.5
• /
• pp.694-701
• /
• 2014

Allium hookeri L. (Alliaceae family) is an important ethnomedicinal plant native to the Himalayan region of Asia. The aim of this research was to establish a high-frequency plant regeneration system for in vitro propagation of A. hookeri. Among the tissue types examined, receptacle explants derived from immature flower buds showed the highest regeneration rate of shoots ($93.33{\pm}4.63%$), roots ($76.67{\pm}7.85%$), and calli ($80.00{\pm}7.43%$) when cultured on Gamborg B5 (B5) medium containing $10{\mu}M$ 6-benzylaminopurine (BA) + $1{\mu}M$ naphthalene acetic acid (NAA), $0.5{\mu}M$ BA + $5{\mu}M$ NAA, and $1{\mu}M$ BA + $10{\mu}M$ NAA, respectively. Shoot multiplication was superior when cultured in liquid rather than on solid medium and relatively high concentrations of BA, ranging from 5 to $10{\mu}M$. Efficient bulblet formation following root induction from shoot clumps was achieved with culture in liquid B5 medium containing 7% (w/v) sucrose. Regenerated bulblets were successfully acclimatized to ex vitro conditions with a greater than 95% survival rate. By this method, a maximum of 62 plantlets per receptacle could be propagated within 9 weeks of initial culture. The in vitro propagation system established in this study will promote A. hookeri biotechnology, including large-scale production of healthy and aseptic clones, preserving parental genotypes with desirable traits, and genetic manipulation to enhance medicinal value.

• Korean Journal of Plant Resources
• /
• v.30 no.6
• /
• pp.612-617
• /
• 2017

The preservation of pear germplasm, like that of other clonal germplasms, is difficult because it requires conservation of whole plants or their tissues. Among the currently available methods for long-term conservation of clonal germplasm, cryopreservation of shoot tips is the most reliable and cost- and space-effective option. Alginate-coated axillary shoot tips from in vitro-grown pear were conserved successfully in liquid nitrogen (LN) following dehydration. Shoot recovery from cryopreserved shoot tips was improved greatly after 8 weeks of cold acclimation, but recovery decreased slightly after then. The highest regeneration rate was observed when in vitro shoot tips were preincubated in MS (Murashige and Skoog) medium with 0.3 M sucrose for 48 h, and when alginate-coated shoot tips were precultured in MS medium with increasing sucrose concentrations (0.5 M and 0.7 M) for 8 and 16 h, respectively. When the encapsulated beads were dehydrated for up to 7 h [25% water content (fresh weight basis)] under laminar flow, the highest regeneration rate was observed in "BaeYun No. 3" (55.7%) and "Whanggeum" (43.3%) after warming from LN. This technique is useful as a practical procedure to cryopreserve plant material that is sensitive to freezing of the surrounding cryoprotectant medium. Therefore, this technique appears to be promising for the cryopreservation of shoot tips from in vitro-grown plantlets of pear germplasm.

• Journal of Plant Biotechnology
• /
• v.6 no.3
• /
• pp.157-163
• /
• 2004

An efficient system for the regeneration of adventitious shoots from in vitro cultured leaf sections of Lycium chinense Miller was developed and silent somaclones from the regenerants detected with RAPD method. Among the eight media tested (B5, SH, N&N, 1/2MS, MS, 3/2MS, GD and WPM), and four cytokinins (BA, kinetin, 2ip and zeatin) with different concentrations (1, 5, 10, 20, 30 and 40 $\mu{M}$), 1/2 MS medium supplemented with 20 and 30 $\mu{M}$ zeatin showed the best regeneration frequency (100% and 93.7%) and higher average number of shoots (9.0 and 9.4). All regenerants easily elongated after subculturing on 1/4MS without growth stimulants and produced spontaneous adventitious roots from their basal parts. With phenotypically normal 40 regenerants, RAPD analysis with 15 different random primers was performed to examine the cryptic somaclonal variants. No substantial differences in banding patterns were found in the amplified polymorphic DNAs implying no DNA changes during dedifferentiation into adventitious shoots. However, one (OPF-4) of the 15 primers detected silent somaclonal variation in one regenerant in which two different polymorphic bands did not appear when compared with the rest regenerants. The results indicate that regenerantion via intervening callus phase can be used to establish true-to-type planting stocks for homogeneous population.

• Journal of Plant Biotechnology
• /
• v.45 no.2
• /
• pp.131-139
• /
• 2018

We examined the effect of carbon sources on the regeneration and ex vitro acclimatization of Lycopus lucidus Turcz. ex Benth. Plantlets were regenerated on the 1/2MS medium supplemented with different concentrations (3 ~ 10%) of sucrose and glucose. The sucrose concentrations of 3% and 5% that were supplied enhanced shoot multiplication and rooting but hampered high concentration growth (including the length of the shoot and root). During ex vitro acclimatization, the tuberization of the root, the root length, the shoot length and the survival rate of Lycopus lucidus plantlets grown using 3% and 5% sucrose were found to be better than the other carbon sources and concentrations. Thus a sucrose concentration of 3% and 5% in the 1/2MS medium appeared to be better for both in vitro growth and ex vitro acclimatization of Lycopus lucidus.

• Journal of Plant Biotechnology
• /
• v.39 no.3
• /
• pp.182-188
• /
• 2012

Iris dichotoma Pall. is an important endangered plant belonging to the family Iridaceae. A method was developed for the rapid micropropagation of I. dichotoma through plant regeneration from leaf, rhizome, and root explant-derived calli. Leaf, rhizome, and root segments were cultured on Murashige and Skoog (MS) medium supplemented with 2,4-dichlorophenoxy acetic acid (2,4-D; $0-3.0mg{\cdot}L^{-1}$) for callus induction. Callus production was highest at $1.0mg{\cdot}L^{-1}$ 2,4-D, where 73.8% and 45.5% of cultured rhizome and root cuttings, respectively, produced calli. The viable calli were maintained at an induced concentration of 2,4-D ($3.0mg{\cdot}L^{-1}$). They were then transferred to MS medium supplemented with various concentrations of 2,4-D ($0-3.0mg{\cdot}L^{-1}$) in combination with 6-benzyladenine (BA: 0, 1.0 and $3.0mg{\cdot}L^{-1}$) for adventitious shoot regeneration. The addition of a low concentration of 2,4-D into BA-containing medium significantly increased the frequency of shoot regeneration in leaf, rhizome, and root-derived calli. The highest number of adventitious shoots (26.4 per callus) formed at $0.5mg{\cdot}L^{-1}$ 2,4-D and 1.0 mg/l BA. For rooting of the shoots, half- strength MS medium supplemented with different concentrations of indole 3-butyric acid (IBA) $0-3.0mg{\cdot}L^{-1}$ was tested. The optimal results were observed using half-strength MS medium supplemented with $1.0mg{\cdot}L^{-1}$ IBA, on which 98% of the regenerated shoots developed roots with an average of 3.5 roots per shoot within 45 days. The plantlets raised in vitro were acclimatized and transferred to soil with 95% success. This in vitro propagation protocol will be useful for conservation and mass propagation of this endangered plant.

• Proceedings of the Plant Resources Society of Korea Conference
• /
• 2018.04a
• /
• pp.36-36
• /
• 2018

Soybean is the important crop in Asian countries as protein source, oil production and animal feed. Improving soybean using genetic transformation is the principal tool in nowadays. Developing herbicide resistant transgenic soybean plants through Agrobacterium-mediated transformation has been worked in many previous studied. However, the transformation efficiency is still low. Many attempts try to find the optimum media condition for plant regeneration after infection. After transformation, the plant regeneration is very important condition to promote growth of transgenic plant. In this study, we optimized a regeneration condition for two Korean soybean cultivar, Dawonkong and Pungsannamulkong using cotyledon, cotyledonary nodes and hypocotyl as explant. The results showed that shoot regeneration of cotyledonary nodes on B5 medium containing 2 mg/L 6-benzylaminopurine showed the highest percentage of regeneration in Dawonkong (75.8%) while Pungsannamulkong presented high number of shoots 2.12 shoots per explant. For transformation condition, co-cultivation in 7 days showed a high number of GUS positive expression. Most of explants can survived under media including 5 mg/L of glufocinate which refers phosphinotricin for 2-week selection. Washing with 400 mg/L of cefotaxime in several times and selection in plant regeneration media with 400 mg/L of cefotaxime can prevent bacteria growth, effectively.