• Research in Plant Disease
• /
• v.29 no.3
• /
• pp.321-329
• /
• 2023

The bacterium Neobacillus endophyticus BRMEA1^T, isolated from the medicinal plant Selaginella involvens, known as its thermotolerant can grow at 50℃. To explore the genetic basis for its heat tolerance response and its potential for producing valuable natural compounds, the genomes of two thermotolerant and four mesophilic strains in the genus Neobacillus were analyzed using a bioinformatic software platform. The whole genome was annotated using RAST SEED and OrthVenn2, with a focus on identifying potential heattolerance-related genes. N. endophyticus BRMEA1^T was found to possess more stress response genes compared to other mesophilic members of the genus, and it was the only strain that had genes for the synthesis of osmoregulated periplasmic glucans. This study sheds light on the potential value of N. endophyticus BRMEA1^T, as it reveals the mechanism of heat resistance and the application of secondary metabolites produced by this bacterium through whole-genome sequencing and comparative analysis.

• Advances in Traditional Medicine
• /
• v.7 no.1
• /
• pp.46-50
• /
• 2007

Callus cultures of Convolvulus microphyllus Sieb. was induced on Murashige and Skoog's medium supplemented with 2,4-dichloro phenoxy acetic acid, 6-benzyl adenine, indole acetic acid and kinetin (1 ppm each). Methanolic extracts of whole plant, leaf, stem and leaf and stem calli were tested for anticonvulsant activity against standard drug phenytoin using maximal electroshock model on mice. It was observed that the animals treated with methanolic extracts of stem callus, leaf callus and whole plant (200 mg/kg, oral) showed significant protection against tonic convulsions induced by transcorneal electroshock. Anticonvulsant activity of methanolic extract of stem callus was comparable to that of standard drug phenytoin.

• Plant Biotechnology Reports
• /
• v.5 no.3
• /
• pp.283-287
• /
• 2011

In order to produce centellosides from whole plant cultures of Centella asiatica (L.) Urban, we evaluated the synergistic effects of thidiazuron (TDZ) and methyl jasmonate (MJ) on whole plant growth and centelloside production. After 4 weeks of treatment with 0.025 mg/L of TDZ coupled with 0.1 mM MJ, the production of made-cassoside and asiaticoside from whole plant cultures was estimated to be 2.40- and 2.44-fold, respectively, above that of MJ elicitation alone. When whole plants were treated with a growth regulator and an elicitor, the growth of whole plants, as compared to the controls, did not differ. Additionally, total phytosyterol content in the leaves of whole plants co-treated with MJ and TDZ was 1.08-fold greater than those of MJ alone. These results demonstrate that combined treatments not only stimulate the accumulation of centellosides in the leaves but also inhibit the reduction of phytosterol levels caused by MJ elicitation.

• Korean Journal of Medicinal Crop Science
• /
• v.13 no.2
• /
• pp.91-94
• /
• 2005

Plants have been known to accumulate a very diverse range of triterpene saponins. We have investigated the regulation of saponin biosynthesis in higher plants using Centella asiatica (L.) Urban as a model plant. Effects of a feeding precursor on asiaticoside production from leaves and on the level of two-type OSCs mRNA were investigated. As a feeding precursor, squalene negatively affected the levels of CYS and bAS mRNA, but it also decreased the production of asiaticoside from whole plants. Plant hormones regulate secondary metabolism, and in plant tissue cultures they could affect both culture growth and secondary metabolite production. Although enhancement of asiaticoside production from whole plant cultures by addition of TDZ (thidiazuron) has been reported, the positive effect of TDZ on the levels of OSCs transcripts was not observed.

• Proceedings of the Korean Society of Plant Biotechnology Conference
• /
• 2002.04b
• /
• pp.157-157
• /
• 2002

• Biotechnology and Bioprocess Engineering:BBE
• /
• v.7 no.3
• /
• pp.138-149
• /
• 2002

Plant cell culture provides a viable alternative over whole plant cultivation for the production of secondary metabolites. In order to successfully cultivate the plant cells at large scale, several engineering parameters such as, cell aggregation, mixing, aeration, and shear sensitivity are taken into account for selection of a suitable bioreactor. The media ingredients, their concentrations and the environmental factors are optimized for maximal synthesis of a desired metabolite. Increased productivity in a bioreactor can be achieved by selection of a proper cultivation strategy (batch, fed-batch, two-stage etc.), feeding of metabolic precursors and extraction of intracellular metabolites. Proper understanding and rigorous analysis of these parameters would pave the way towards the successful commercialization of plant cell bioprocesses.

• Journal of Plant Biotechnology
• /
• v.3 no.1
• /
• pp.39-44
• /
• 2001

Plastid transformation was attempted with soybean [Glycine max (L.) Merr.] leaves and photoautotrophic and embryogenic cultures by particle bombardment using the transforming vector pZVII that carries the coding sequences for both subunits of Chlamydomonas reinhardtii Rubisco and a spectinomycin resistance gene (aadA). Spectinomycin resistant calli were selected from the bombarded leaves but the transgene was not present, indicating that the resistance was due to mutations. The Chlamydomonas rbcL and rbcS genes were shown to be site-specifically integrated into the plastid genome of the embryogenic cells with a very low transformation efficiency. None of the transformed embryogenic lines survived the plant regeneration process so no whole plants were recovered. This result does indicate that it should be possible to insert genes into the plastid genome of the important crop soybean if the overall methods are improved.

• Journal of Plant Biotechnology
• /
• v.29 no.4
• /
• pp.281-285
• /
• 2002

Whole plant cultures of Centella asiatica (L.) Urban in vitro were established and the effects of basal media, some macro elements and sucrose concentration on productivity of triterpene glycosides (madecassoside and asiaticoside: M$\varepsilon$A) were investigated. Among the media (MS, B5, RCM) tested, MS and 0.5 RCM medium were the best for plant growth and M$\varepsilon$A production, respectively. However, taking into account the M$\varepsilon$A productivity, B5 medium was superior (M$\varepsilon$A: 14.28 mg/g dry wt.). Major macronutrients of B5 medium adjusted with the concentration of 25 mM KNO$_3$,1 mM NaH$_2$PO$_4$, 1 mM CaCl$_2$ and 1~10 mM MgSO$_4$, caused elevated or optimized levels of M$\varepsilon$A. On sucrose concentration, the highest yields of M$\varepsilon$A were obtained from 6% sucrose.

• Journal of Plant Biotechnology
• /
• v.34 no.3
• /
• pp.207-212
• /
• 2007

This study describes a simple and rapid method for quantitative determination of $\gamma$-aminobutyric acid (GABA) using $^1H$ NMR spectroscopy from whole cell extracts of plant suspension cultures. When 9 cell lines derived from 8 species of higher plants maintained in liquid Marashige and Skoog (MS) medium supplemented with 1 mg/L 2,4-dichlorophenoxyacetic acid (2,4-D) were subjected to $^1H$ NMR, a cell line of Coriandrum sativum L. exhibited the highest level of GABA. The level reached up to 16.9 mg/dry wt when cells were cultured in MS medium supplemented with 0.5 mg/L 2,4-D after 3 weeks of incubation. The method for quantitative determination of GABA using $^1H$ NMR established in this study could be applied to high-throughput screening of various plant resources for GABA production and the cell suspension culture system of C. sativum could be further developed for commercial production of GABA.

• Plant Biotechnology Reports
• /
• v.3 no.3
• /
• pp.199-203
• /
• 2009

Rugosa rose (Rosa rugosa) is cultivated as a garden flower and an important genetic resource for the breeding of roses (R. hybrida). This study describes culture conditions for high frequency plant regeneration from zygotic embryo explants via somatic embryogenesis in rugosa rose. Mature zygotic embryo, cotyledon, and radicle explants formed embryogenic calluses at frequencies of 38, 6.7, and 8.8% when cultured on half-strength Murashige and Skoog medium (${\frac{1}{2}}MS$) supplemented with 2.26, 9.05, and $9.05{\mu}M$ 2,4-dichlorophenoxyacetic acid, respectively. Embryogenic calluses produced numerous somatic embryos, which then developed into plantlets on ${\frac{1}{2}}MS$ without growth regulators. Regenerated plantlets were grown to whole plants in a growth chamber.