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161.
162.
U. A. Jo H. N. Murthy E. J. Hahn K. Y. Paek 《In vitro cellular & developmental biology. Plant》2008,44(1):26-32
An efficient, simple micropropagation method was developed for Alocasia amazonica using corms in semisolid and liquid cultures. Explants were cultured onto Murashige and Skoog (MS) medium (Murashige and
Skoog, Physiol. Plant. 15:473–497, 1962) supplemented with different cytokinins (Benzyladenine [BA, 2.22–13.32 μM], kinetin [2.32–13.95 μM], Thidiazuron [TDZ, 0.45–4.54 μM])
and cytokinin in combination with auxins [naphthalene acetic acid (NAA, 0.54–5.37 μM)/indole acetic acid (IAA, 0.57–5.71 μM)/indole
butyric acid (IBA, 0.49–4.9 μM)]. All supplementary-induced shoot proliferation and the optimal results was on the medium
supplemented with 2.27 μM TDZ, which induced 5.1 shoots per explant. Among the different concentrations of sucrose (0–120 g
l−1) tested for shoot proliferation, 30 g l−1 was found suitable for corm cultures of Alocasia amazonica. The optimal shoot proliferation and biomass values were with the plantlets grown at 30 μmol m−2 s−1 photosynthetic photon flux (PPF) and 25°C. Liquid cultures found suitable for shoot proliferation and biomass accumulation
was compared to semisolid cultures. Comparative studies of bioreactor systems [continuous immersion (with or without net)
and temporary immersion in liquid media using ebb and flood] revealed that shoot multiplication and growth were greatest with
the raft bioreactor system. Plantlets (cormlets) from the bioreactor were hydroponically cultured for 30 days, and 100% of
plants were acclimatized successfully. The simple efficient method of production of plantlets (cormlets) is useful for large-scale
multiplication of this important ornamental plant.
An erratum to this article can be found at 相似文献
163.
A rapid and efficient procedure is outlined for in vitro clonal propagation of an elite cultivar of jewel orchid (Anoectochilus formosanus). Multiple shoot proliferation was induced in shoot tip explants on Hyponex (H3) media supplemented with 1 mg dm–3 benzyladenine or 1 – 2 mg dm–3 thidiazuron (TDZ). Addition of activated charcoal (1 g dm–3) to the TDZ containing medium promoted multiple shoot formation (11.1 shoots per explant). However, the regenerated shoots had slow growth rate and failed to elongate. This problem was overcome by transferring the shoot clumps to a hormone free H3 medium supplemented with 2 % sucrose and 0.5 g dm–3 activated charcoal. Rooting was induced in 100 % of the regenerated shoots in the same media. The plantlets were acclimatized and established in greenhouse. 相似文献
164.
The effect of light quality on the growth and development of in vitro cultured Doritaenopsis plants 总被引:5,自引:0,他引:5
Kong Sik Shin Hosakatte Niranjana Murthy Jeong Wook Heo Eun Joo Hahn Kee Yoeup Paek 《Acta Physiologiae Plantarum》2008,30(3):339-343
The influence of light quality on growth and development of in vitro grown Doritaenopsis hort. (Orchidaceae) plants was investigated. Growth parameters like leaf and root fresh/dry mass and leaf area were highest
with plants grown under red plus blue light emitting diodes (LEDs). Leaf length was greater with the plants grown under red
LED. Carbohydrate (starch, sucrose, glucose and fructose) and leaf pigment (chlorophylls and carotenoids) biosynthesis of
the plants was significantly increased in plants grown under red plus blue LEDs compared to red or blue LED and fluorescent
light treatments. This study suggests that the production of quality Doritaenopsis plants is possible by culturing the plants in vitro under a mixture of blue plus red light sources. 相似文献
165.
Involvement of nitric oxide-induced NADPH oxidase in adventitious root growth and antioxidant defense in Panax ginseng 总被引:1,自引:0,他引:1
Rajesh Kumar Tewari Soohyun Kim Eun-Joo Hahn Kee-Yoeup Paek 《Plant biotechnology reports》2008,2(2):113-122
Nitric oxide (NO) affects the growth and development of plants and also affects plant responses to various stresses. Because
NO induces root differentiation, we examined whether or not it is involved in increased ROS generation. Treatments with sodium
nitroprusside (SNP), an NO donor, 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (PTIO), a specific NO scavenger,
and Nω-nitro-l-arginine methyl ester hydrochloride (l-NAME), an NO synthase (NOS) inhibitor, revealed that NO is involved in the adventitious root growth of mountain ginseng.
Supply of an NO donor, SNP, activates NADPH oxidase activity, resulting in increased generation of O2
·−, which subsequently induces growth of adventitious roots. Moreover, treatment with diphenyliodonium chloride (DPI), an NADPH
oxidase inhibitor, individually or with SNP, inhibited root growth, NADPH oxidase activity, and O2
·− anion generation. Supply of the NO donor, SNP, did not induce any notable isoforms of enzymes; it did, however, increase
the activity of pre-existing bands of NADPH oxidase, superoxide dismutase, catalase, peroxidase, ascorbate peroxidase, and
glutathione reductase. Enhanced activity of antioxidant enzymes induced by SNP supply seems to be responsible for a low level
of H2O2 in the adventitious roots of mountain ginseng. It was therefore concluded that NO-induced generation of O2
·− by NADPH oxidase seems to have a role in adventitious root growth of mountain ginseng. The possible mechanism of NO involvement
in O2
·− generation through NADPH oxidase and subsequent root growth is discussed. 相似文献
166.
Thanh-Tam Ho Kyung-Ju Lee Jong-Du Lee Shashi Bhushan Kee-Yoeup Paek So-Young Park 《Plant Cell, Tissue and Organ Culture》2017,130(1):167-181
Polygonum multiflorum Thunb. is an important medicinal plant that synthesizes an array of phenolic compounds. Its roots are used in a variety of pharmacological and cosmetic formulations, notably as hair dye. In the present study, the inoculum density (3–15 g/L) and culture period (1–7 weeks) were optimized in a 3 L bioreactor. High root biomass (14.18 g/L dry weight (DW)) was recorded with an inoculum of 7 g/L (p?≤?0.05), which is consistent with the results for 5 and 10 g/L. However, significantly higher yield of bioactive compounds (53.87 mg/g DW total phenolics and 27.96 mg/g DW total flavonoids) with high free radical scavenging activity was obtained in root samples from 5 g/L inoculum density. A 4 week culture period was sufficient for optimum root growth and metabolite production. The optimized conditions were used for large-scale (5 and 20 L) and pilot-scale (500 L) studies. Considering that the continuous aeration of root cultures may lead to oxidative stress, antioxidant enzyme activity and lipid peroxidation also were studied. The results revealed high catalase (CAT) and guaiacol peroxidase (G-POD) activities, and low malondialdehyde (MDA) production, with increasing culture scale (20 and 500 L), which may indicate low-level oxidative damage to the cultures. An optimal yield of 4.01 kg dry root biomass with 287.12 mg/L of total phenolic productivity was achieved in a 500 L pilot-scale bioreactor. This work can pave the way for commercial production of biomass and secondary metabolites at the industrial level, and meet the rising demand for natural ingredients, especially in the pharmaceutical and cosmetic industries. 相似文献
167.
A survey of different types of cereal straw samples viz. paddy, maize and wheat, from Bihar State, India, was conducted in
order to examine the mould flora and mycotoxin contamination. Out of 170 samples examined for mould flora,Aspergillus flavus group of fungi had highest level of incidence followed byA niger. Isolates ofA flavus, A ochraceus, Fusarium verticillioides andPenicillium citrinum were screened for their mycotoxins producing abilities. Out of 75, 63 and 68 isolates ofA flavus group obtained from stored straw of paddy, maize and wheat samples, respectively, 27 (36%), 14 (22%) and 24 (35%) were found
to be toxigenic which produced different combinations of aflatoxins in different concentrations. The percentage toxigenicity
was comparatively lower in the isolates of other mycotoxigenic fungi from all types of samples. Out of 222 samples of straw
analysed for natural occurrence of different mycotoxins, besides the aflatoxins present, zearalenone, ochratoxin A and citrinin
were also recorded alone or as co-contaminants. A conducive climate together with the socioeconomic conditions of this region
are important determinants for the high incidence of mycotoxins in cereal straw samples. 相似文献
168.
Genetic transformation of Cymbidium orchid by particle bombardment 总被引:13,自引:0,他引:13
J. Yang H.-J. Lee D. H. Shin S. K. Oh J. H. Seon K. Y. Paek K.-H. Han 《Plant cell reports》1999,18(12):978-984
A protocol is presented for genetically engineering Cymbidium orchid using particle bombardment. This protocol enabled the routine transformation of orchid plants that were previously
difficult to transform. Liquid culture was used to generate a large number of protocorm-like bodies (PLBs) to be bombarded
and to promote continued development of the bombarded meristematic tissue. Plasmid DNA (pKH200) carrying the GUS-INT and NPTII
genes flanked by tobacco matrix attachment regions was introduced into the meristematic cells of PLBs by particle acceleration.
The transformed PLBs were proliferated and selected for kanamycin resistance conferred by the introduced NPTII gene. Shoot
regeneration was then induced from the kanamycin-resistant PLBs, and transgenic plantlets were produced. Both the kanamycin-resistant
PLBs and regenerated shoots expressed the GUS-INT gene. The presence of the introduced gene in the transformed orchid plants
was confirmed by PCR analysis, sequencing and Southern blot analysis of the PCR product. The recovered transgenic plants were
established in soil and acclimatized in the greenhouse.
Received: 20 July 1998 / Revision received: 2 December 1998 / Accepted: 17 December 1998 相似文献
169.
The increasing global demand for biomass of medicinal plant resources reflects the issues and crisis created by diminishing renewable resources and increasing consumer populations. Moreover, diverse usage of plants and reduced land for cultivation in the world accelerated the deficiency of plant resources. In addition, the preparation of safety of plant based medicine whips up demand for biomass of valuable medicinal plants. As one of alternative approach to upswing the productivity of plant-based pharmaceutical compounds, automation of adventitious root culture system in air-lift bioreactor was adopted to produce cosmic amount of root biomass along with enriched diverse bioactive molecules. In this review, various physiological, engineering parameters, and selection of proper cultivation strategy (fed-batch, two-stage etc.) affecting the biomass production and secondary metabolite accumulation have been discussed. In addition, advances in adventitious root cultures including factors for process scale-up as well as recent research aimed at maximizing automation of the bioreactor production processes are also highlighted. Examples of the scale-up of cultures of adventitious roots of Morinda citrifolia, Echinacea purpurea and angustifolia, Hypericum perforatum and Panax ginseng by applying 20L to 10,000L bioreactors in our lab were demonstrated with a view of commercial application. 相似文献
170.
Post-translational modifications (PTMs) play key roles in the regulation of biological functions of proteins. Although some progress has been made in identifying several PTMs using existing approaches involving a combination of affinity-based enrichment and mass spectrometric analysis, comprehensive identification of PTMs remains a challenging problem in proteomics because of the dynamic complexities of PTMs in vivo and their low abundance. We describe here a strategy for rapid, efficient, and comprehensive identification of PTMs occurring in biological processes in vivo. It involves a selectively excluded mass screening analysis (SEMSA) of unmodified peptides during liquid chromatography-electrospray ionization-quadrupole-time-of-flight tandem mass spectrometry (LC-ESI-q-TOF MS/MS) through replicated runs of a purified protein on two-dimensional gel. A precursor ion list of unmodified peptides with high mass intensities was obtained during the initial run followed by exclusion of these unmodified peptides in subsequent runs. The exclusion list can grow as long as replicate runs are iteratively performed. This enables the identifications of modified peptides with precursor ions of low intensities by MS/MS sequencing. Application of this approach in combination with the PTM search algorithm MODi to GAPDH protein in vivo modified by oxidative stress provides information on multiple protein modifications (19 types of modification on 42 sites) with >92% peptide coverage and the additional potential for finding novel modifications, such as transformation of Cys to Ser. On the basis of the information of precursor ion m/z, quantitative analysis of PTM was performed for identifying molecular changes in heterogeneous protein populations. Our results show that PTMs in mammalian systems in vivo are more complicated and heterogeneous than previously reported. We believe that this strategy has significant potential because it permits systematic characterization of multiple PTMs in functional proteomics. 相似文献