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1.
Solanum chrysotrichum (Solanaceae) synthesizes a family of six antifungal spirostanol saponins designated as SC-1 to SC-6. The production of saponins
by wild-type plants is variable depending on the environmental conditions. In order to develop an in vitro system for the sustained production of these saponins, transformed cell suspension cultures of S. chrysotrichum were established from nodal explants of 3-mo-old plantlets by infecting with the Agrobacterium tumefaciens strain C58/pBI12. From these cultures, kanamycin-resistant and phytohormone-independent cell suspension line C58 5.1.1 was
obtained. PCR and Southern blot analyses were used to confirm the integration of the wild-type T-DNA into the plant genome.
Batch cultures of the C58 5.1.1 cell line were grown in phytohormone-free MS liquid medium for 25 d. First-order growth kinetics
and the production of the antifungal saponins (SC-2, SC-3, and SC-4) were determined by dry weight and quantified by HPLC,
respectively, from the cells as well as the culture medium. Based on the cell biomass, the specific growth rate was 0.09 d −1 and the yield of SC-2 reached 5.5% of dry weight, representing 40 times higher amount than that produced in plant leaves.
SC-3 was recovered with a maximum yield of 0.9% of dry weight, whereas SC-4 was accumulated at 1.1% of dry weight. Saponins
SC-2 and SC-3 were also excreted into the culture medium in low concentrations. 相似文献
2.
In vitro cultured carnivorous plants were grown on a hormone-free medium. They produced the following naphthoquinones: Dionaea muscipula (plumbagin: 5.3%), Drosera rotundifolia (7-methyljuglone: 0.6%), D. binata (plumbagin: 1.4%), and D. capensis (7-methyljuglone: 0.5%). A red, slow-growing suspension culture of D. muscipula was maintained in a modified McCowns Woody Plant (McC) medium and produced plumbagin (2.59%) after 30 days growth. A suspension culture of D. rotundifolia grew slowly as multicoloured small aggregates only in a modified Murashige and Skoog (MS) medium. No quantifiable amounts of naphthoquinones were produced. Several cell lines of D. capensis were developed. Green aggregates grown in a modified MS medium contained 7-methyljuglone (0.33%) and differentiated into plants when placed onto hormone-free medium. Pink cultures grown in modified McC medium contained 7-methyljuglone (1.24%), while dark red cultures produced ca. 1% in both modified McC and MS media. Though the latter medium was significantly better with regard to biomass production, cells excreted a mucin when cultured in both media (0.21 g dry mucin/g dry cells in McC) and (0.16 g dry mucin/g dry cells in MS). Effects of the presence or absence of light during the growth period of 30 days showed that there was no effect on biomass and only slight effects on mucin production and naphthoquinone contents. 相似文献
3.
The present study was aimed to develop a membrane sparger (MS) integrated into a tubular photobioreactor to promote the increase of the carbon dioxide (CO 2) fixation by Spirulina sp. LEB 18 cultures. The use of MS for the CO 2 supply in Spirulina cultures resulted not only in the increase of DIC concentrations but also in the highest accumulated DIC concentration in the liquid medium (127.4 mg L −1 d −1). The highest values of biomass concentration (1.98 g L −1), biomass productivity (131.8 mg L −1 d −1), carbon in biomass (47.9% w w −1), CO 2 fixation rate (231.6 mg L −1 d −1), and CO 2 use efficiency (80.5% w w −1) by Spirulina were verified with MS, compared to the culture with conventional sparger for CO 2 supply. Spirulina biomass in both culture conditions had high protein contents varying from 64.9 to 69% (w w −1). MS can be considered an innovative system for the supply of carbon for the microalgae cultivation and biomass production. Moreover, the use of membrane system might contribute to increased process efficiency with a reduced cost of biomass production. 相似文献
4.
The effect of culture filtrate (conditioned medium, CM) containing cell exudates obtained from green alga, Scenedesmus subspicatus, on cell suspension of dicotyledonous plant Silene vulgaris was examined. The addition of diluted CM to the modified MS medium, supplemented with dicamba and BAP, stimulates cell biomass
production. The biomass was composed of association of single non-dividing cells, cells during mitosis stage and cellular
aggregates. Silene cells began mitotic divisions earlier in the presence of CM in medium when compared to control treatments. Results of performed
bioassay showed that some factor or factors released by green alga to the culture medium could be responsible for sustained
proliferation of phylogenetically distant species cells. Although it is still unclear which culture constituent influenced
most the mitotic response of Silene suspension, results point at versatile stimulatory character of green alga exudates in higher plant cell culture. 相似文献
5.
The effect of culture medium nutrients on growth and alkaloid production by plant cell cultures of Nothapodytes nimmoniana (J. Grah.) Mabberley (Icacinaceae) was studied with a view to increasing the production of the alkaloid camptothecin, a key therapeutic drug used for its anticancer properties. Amongst the various sugars tested with Murashige and Skoog (MS) medium, such as glucose, fructose, maltose, and sucrose, maximum accumulation of camptothecin was observed with sucrose. High nitrate in the media supports the biomass, while high ammonium enhances the camptothecin content. Selective feeding of 60 mM total nitrogen with a NH 4 +/NO 3 ? balance of 5/1 on day 15 of the culture cycle results in a 2.4-fold enhancement in the camptothecin content over the control culture (28.5 μg/g DW). Furthermore, the sucrose feeding strategy greatly stimulated cell biomass and camptothecin production. A modified MS medium was developed in the present study, which contained 0.5 mM phosphate, a nitrogen source feeding ratio of 50/10 mM NH 4 +/NO 3 ? and 3 % sucrose with additional 2 % sucrose feeding (added on day 12 of the cell culture cycle) with 10.74 μM naphthaleneacetic acid and 0.93 μM kinetin. Finally, the selective medium has 1.7- and 2.3-fold higher intracellular and extracellular camptothecin content over the control culture (29.2 and 8.2 μg/g DW), respectively. 相似文献
6.
A high efficient four step protocol (callus initiation, regeneration, shoot elongation and rooting) for in vitro propagation of Dracaena sanderiana Sander ex Mast was developed. Callusing was achieved from nodal stem segment explants treated with various concentrations of ethylmethane
sulphonate (EMS) on MS medium supplemented with 2,4-dichlorophenoxyacetic acid (2,4-D; 1.5 g m −3). A significant increase in callus induction percentage and biomass production was noticed from lower EMS treated lines (ET 1 and ET 2) comparatively to control and other (ET 3, ET 4 and ET 5) lines. Calli of ET 1 line showed high regeneration potential on MS medium with N
6-benzylaminopurine (BAP; 1.75 g m −3). Length of microshoots, which was reduced by EMS, restored by addition of gibberellic acid (GA 3; 0.4 g m −3). A marked increase in rooting with increasing EMS concentration was noticed on MS medium fortified with 3-indolebutyric
acid (IBA; 1.5 g m −3). 相似文献
7.
The effects of different levels of Murashige and Skoog (MS) basal medium, 2,4-dichlorophenoxyacetic acid (2,4-D), and sucrose
on anthocyanin production and biomass accumulation of cell suspension cultures of Cleome rosea were investigated. Cultures were established in liquid MS medium containing 30 g l −1 sucrose and supplemented with 0.90 μM 2,4-D. Proliferating cell suspension cultures achieved the highest growth capacity,
a fourfold increase in biomass accumulation, following subculture at the exponential growth phase, 14–18 days of culture.
Moreover, the presence of 2,4-D was essential for anthocyanin production and biomass accumulation. On the other hand, increasing
levels of sucrose above 30 g l −1 resulted in a drastic reduction in biomass accumulation. Anthocyanin production was highest in cell suspension cultures grown
on half-strength MS medium (1/2 MS), 30 g l −1 sucrose, and 0.45 μM 2,4-D. These cell suspension cultures were mainly composed of small aggregates of spherical cells with
similar morphology observed in anthocyanin-producing and non-producing cultures. Moreover, microscopic analysis of anthocyanin-producing
cultures showed the presence of mixtures of non-pigmented, low-pigmented, and high-pigmented cells. 相似文献
8.
Withanolides are biologically active secondary metabolites present in roots and leaves of Withania somnifera. In the present study, we have induced adventitious roots from leaf explants of W. somnifera for the production of withanolide-A, which is having pharmacological activities. Adventitious roots were induced directly
from leaf segments of W. somnifera on half strength Murashige and Skoog (MS) semisolid medium (0.8% agar) with 0.5 mg l −1 indole-3-butyric acid (IBA) and 30 g l −1 sucrose. Adventitious roots cultured in flasks using half strength MS liquid medium with 0.5 mg l −1 IBA and 30 g l −1 showed higher accumulation of biomass (108.48 g l −1FW and 10.76 g l −1 DW) and withanolide-A content (8.8 ± 0.20 mg g −1 DW) within five weeks. Nearly 11-fold increment of fresh biomass was evident in suspension cultures and adventitious root
biomass produced in suspension cultures possessed 21-fold higher withanolide-A content when compared with the leaves of natural
plants. An inoculum size of 10 g l −1 FW favoured the biomass accumulation and withanolide-A production in the tested range of 2.5, 5.0, 10.0 and 20.0 g l −1 FW. Among different media tested [Murashige and Skoog (MS), Gamborg’s (B5), Nitsch and Nitsch (NN) and Chu’s (N6)], MS medium
favoured both biomass accumulation and withanolide-A production. Half strength MS medium favoured the biomass accumulation
and withanolide-A production among the different strength MS medium tested (0.25, 0.5, 0.75, 1.0, 1.5 and 2.0). The current
results showed great potentiality of adventitious roots cultures for the production of withanolide-A. 相似文献
9.
An ecotype of brake fern ( Pteris vittata) was assessed for arsenic tolerance and accumulation in its biomass under in vivo and in vitro condition; using soil, and
agar-gelled Murashige and Skoog (MS) medium supplemented with different concentrations of arsenic. The plants were raised
in soil amended with 100–1000 mg arsenic kg −1 soil, and MS medium was supplemented with 10–300 mg arsenic 1 −1 medium using Na 2HAsO 4 · 7H 2O. The spores and haploid gametophytic-prothalli were raised in vitro on MS medium supplemented with arsenic. The field plants
showed normal growth and biomass formation in arsenic amended soil, and accumulated 1908–4700 mg arsenic kg −1 dry aerial biomass after 10 weeks of growth. Arsenic toxicity was observed above >200 mg arsenic kg −1 soil. The concentrations of arsenic accumulated in the plant biomass were statistically significant ( p < 0.05). Normal plants were developed from spores and gametophyte prothalli on the MS media supplemented with 50–200 mg arsenic
1 −1 medium. The in vitro raised plants were tolerant to 300 mg arsenic kg −1 of soil and accumulated up to 3232 mg arsenic kg −1 dry aerial biomass that showed better growth performance, biomass generation and arsenic accumulation in comparison to the
field plants.
The text was submitted by the authors in English. 相似文献
10.
Hazelnut (Corylus avellana L.), contains a valuable medicinal substance known as Paclitaxel®, which is one of the most effective anticancer drugs. The original plants produce negligible amount of paclitaxel; therefore, tissue culture techniques, especially hairy root culture, could be one of the most practical methods to enhance the amount of paclitaxel. The main goal of this study was to assess the induction of hairy roots in C. avellana. The effects of different strains of Agrobacterium rhizogenes including c58c1pRiA4, K599, and 15834, and six culture media, MS (Murashige and Skoog), half-strength MS, quarter-strength MS, WPM (woody plant media), half-strength WPM, and quarter-strength WPM, were evaluated. The results showed that the maximum amounts of the rooted explants were obtained with c58c1pRiA4 strain in quarter-strength WPM medium. The investigations of explant type (leafstalk, petiole, lamina, and stem) and different propagation media (quarter-strength WPM, half-strength MS, and half-strength SH ((Schenk and Hildebrandt) medium) showed that the leafstalk was the most optimal explant for hairy root induction, and half-strength SH was the best culture medium for growth of the hairy roots in liquid medium. HPLC analyses confirmed the presence of paclitaxel (3.2 μg g−1 (DW)) in hairy root extracts. 相似文献
11.
An oxalate-resistant strain of Ashbya gossypii was naturally isolated from spores grown on an oxalate-containing medium, and its medium was optimized to improve riboflavin
production. Riboflavin production by the resistant strain was three-fold higher than that by the wild-type organism when grown
in flask cultures. Medium optimization increased the riboflavin production by the resistant strain to 5 g l −1, which was five-fold higher than that obtained by the wild-type strain. The productivity was reproduced in a 3-l bioreactor.
During the early growth phase, the specific activity of isocitrate lyase in the oxalate-resistant strain was slightly higher
than that in the wild-type strain. Proteomic analysis of the oxalate-resistant strain revealed that the expression of aldose
reductase and cobalamin-independent methionine synthase decreased significantly. This is the first report that describes the
natural isolation of a riboflavin producer using an antimetabolite-containing medium to enhance the riboflavin production
level. This method should also be useful for improving the productivity of other bioproducts since it does not require any
mutations or genetic modifications of the microorganism. 相似文献
12.
The present work deals with optimization of adventitious shoot culture of Bacopa monnieri for the production of biomass and bacoside A and has investigated the effects of macro elements (NH 4NO 3, KNO 3, CaCl 2, MgSO 4 and KH 2PO 4) and nitrogen source [NH 4
+/NO 3
−] of Murashige and Skoog (Physiol Plant 15:473–497, 1962) medium (MS) on accumulation of biomass and bacoside A content. Optimum number of adventitious shoots (99.33 shoots explant −1), fresh weight (1.841 g) and dry weight (0.150 g) were obtained in the medium with 2.0× strength of NH 4NO 3. The highest production of bacoside A content was also recorded in the medium of 2.0× NH 4NO 3, which produced 17.935 mg g −1 DW. The number of adventitious shoot biomass and bacoside A content were optimum when the NO 3
− concentration was higher than that of NH 4
+. Maximum number of shoots (70.00 shoots explant −1), biomass (fresh weight 1.137 g and dry weight 0.080 g) and also bacoside A content (27.106 mg g −1 DW) were obtained at NH 4
+/NO 3
− ratio of 14.38/37.60 mM. Overall, MS medium supplemented with 2.0× NH 4NO 3 is recommended for most efficient bacoside A production. 相似文献
13.
Summary A new variant, Candida boidinii variant 60, which is less sensitive to methanol and formaldehyde shocks was grown in continuous cultures with methanol as sole carbon source. The substrate concentration in the feeding medium was either 1% methanol or 3% methanol. Biomass production, methanol consumption, the formation of formaldehyde and gas exchange were measured at different dilution rates. With low methanol feeding (10 g/l) maximal productivity of 0.44 g biomass/l·h is obtained at a dilution rate of 0.14 h –1. Maximal specific growth rate is 0.18 h –1. A yield of 0.32 g biomass/g methanol was obtained and the respiration quotient was determined as 0.55. Independently of initial substrate concentration, biomass decreases if methanol and formaldehyde are accumulating in the culture broth.In the culture with high methanol feeding (30 g/l) cell concentratioon increases up to 9 g/l at D=0.04 h –1. At higher dilution rates methanol and form-aldehyde appear in the medium. Formaldehyde is then preferably oxidized without energy advantages for the cells. It seems that this enables the cells to overcome toxic effects caused by methanol and formaldehyde. 相似文献
14.
The effects of organic carbon sources on cell growth and exopolysaccharide (EPS) production of dissociated Nostoc flagelliforme cells under mixotrophic batch culture were investigated. After 7?days of cultivation, glycerol, acetate, sucrose, and glucose increased the final cell density and final EPS concentrations, and mixotrophic growth achieved higher biomass concentrations. The increase in cell growth was particularly high when glucose was added as the sole carbon source. On the other hand, EPS production per dry cell weight was significantly enhanced by adding acetate. For more effective EPS production, the effects of the mixture of glucose and acetate were investigated. Increasing the ratio of glucose to acetate resulted in higher growth rate with BG-11 medium and higher EPS productivity with BG-11 0 medium (without NaNO 3). When the medium was supplemented with a mixture of glucose (4.0?g?L ?1) and acetate (2.0?g?L ?1), 1.79?g?L ?1 biomass with BG-11 medium and 879.6?mg?L ?1 of EPS production with BG-11 0 medium were achieved. Adopting this optimal ratio of glucose to acetate established in flask culture, the culture was also conducted in a 20-L photobioreactor with BG-11 medium for 7?days. A maximum biomass of 2.32?g?L ?1 was achieved, and the EPS production was 634.6?mg?L ?1. 相似文献
15.
Summary Rice cells derived from PI 353705 (similar to Assam 5) were isolated from anthers cultured on Blaydes medium containing IAA,
2,4-D, kinetin, yeast extract, and coconut milk. Isolated aggregates of cells were plated on a modified Blaydes medium containing
10 −3
M S-aminoethyl- l-cysteine ( S-AEC). This level of S-AEC inhibits nonselected wild type cells. Cells or aggregates of cells resistant to this analog of lysine were subcultured
three times in the presence of 2×10 −3
M S-AEC. The selected cells were then placed on a Murashige-Skoog (MS) regenerating medium containing 1 mg/l each of IAA and
kinetin. Ten plants were recovered from 34 selected cell lines, three plants grew to maturity, and two produced seeds. Seeds
from plants regenerated from cells in culture had higher lysine than the original field controls and had increased levels
of free alanine, arginine, and asparagine. The in vitro selection produced plants with higher protein than the field controls.
Plant breeders have begun to evaluate the genotype recovered from in vitro selection. 相似文献
16.
During the growth of the asporogenous variant of Bacillus megaterium KM in medium containing NO 3
− as nitrogen source, the relative rate of extracellular protease synthesis is higher than in the presence of NH 4
+. It approaches the relative rate of enzyme synthesis at the incubation of cells in nitrogen-free medium with glucose. This
supports the suggestion that even amino acids which are synthesized endogenously slow down the protease production. In the
postlogarithmic or stationary phase the protease production stops. The interruption of enzyme production does not appear as
a result of insufficient aeration in a dense suspension, or of accumulation of amino acids or their metabolites in cells.
The non-growing cells retain their ability to renew the enzyme synthesis when transferred into a fresh medium, even into a
medium without nitrogen source. In the same way it is possible to “induce” the protease production, if Ca 2+ is added to cells in the stationary phase when the population was grown in the Ca 2+ free medium. The amount of enzyme produced at the expense of protein turnover by the non-growing populations is sufficient
for the fast hydrolysis of exogenous protein in the medium and for assuring the influx of a sufficient amount of peptides
into the cells. In such a case the growth of the culture is therefore very quickly renewed. 相似文献
17.
Callus of Orthosiphon stamineus could be induced successfully from petiole, leaf and stem tissues but not roots when cultured on MS medium containing different concentration of NAA (0–4.0 mg l –1) and 2,4-D (0–2.0 mg l –1). Highest fresh weight callus production was obtained from leaf explants and those with best friability were obtained on MS medium plus 1.0 mg l –1 2,4-D plus 1.0 mg l –1 NAA. Cell suspension cultures were established from these cultures. The appropriate cell inoculum size for the best cell growth was 0.75 g of cells in 20 ml culture medium. Cell suspension culture using MS medium supplemented with 1.0 mg l –1 2,4-D promoted the best cell growth with maximum biomass of 8.609 g fresh weight and 0.309 g dry weight 24 days after inoculation. Cells that grew in MS medium supplemented with 1.0 mg l –1 2,4-D reached the stationary growth phase in 15 days as compared to the cells that grew in MS medium supplemented with 1.0 mg l –1 2,4-D + 1.0 mg l –1 NAA reached the stationary phase in 24 days. MS medium supplemented with 1.0 mg l –1 2,4-D was considered as the maintenance medium for maintaining the optimum cell growth of O. stamineus in the cell suspension cultures with 2-week interval subculture. 相似文献
18.
The prevention of enormous crop losses caused by pesticide-resistant fungi is a serious challenge in agriculture. Application of alternative fungicides, such as antifungal proteins and peptides, provides a promising basis to overcome this problem; however, their direct use in fields suffers limitations, such as high cost of production, low stability, narrow antifungal spectrum and toxicity on plant or mammalian cells. Recently, we demonstrated that a Penicillium chrysogenum-based expression system provides a feasible tool for economic production of P. chrysogenum antifungal protein (PAF) and a rational designed variant (PAF opt), in which the evolutionary conserved γ-core motif was modified to increase antifungal activity. In the present study, we report for the first time that γ-core modulation influences the antifungal spectrum and efficacy of PAF against important plant pathogenic ascomycetes, and the synthetic γ-core peptide Pγ opt, a derivative of PAF opt, is antifungal active against these pathogens in vitro. Finally, we proved the protective potential of PAF against Botrytis cinerea infection in tomato plant leaves. The lack of any toxic effects on mammalian cells and plant seedlings, as well as the high tolerance to harsh environmental conditions and proteolytic degradation further strengthen our concept for applicability of these proteins and peptide in agriculture. 相似文献
19.
To develop a cost effective process for bioinsecticides production by Photorhabdus temperata, dissolved oxygen (DO) requirements were investigated in both the complex and the optimized media using diluted seawater as a source of micronutrients. By varying DO concentrations, tolerance to hydrogen peroxide was shown to be medium dependant. Indeed, P. temperata cells grown in the complex medium, exhibited higher tolerance than cells grown in the optimized medium (OM). Tolerance to H 2O 2 was shown to be related to intracellular reactive oxygen species (ROS) accumulation during soya bean meal or glucose assimilation, as shown by flow cytometry analysis. To avoid oxidative stress damages in P. temperata cells cultured in the OM, DO concentration should be constant 50% saturation throughout the fermentation. However, a DO‐shift control strategy was demonstrated to be beneficial for P. temperata bioinsecticide production in the complex medium. By using such a strategy biomass, culturability, and oral toxicity reached 16.5 × 10 8, 1.15 × 10 8 cells/mL and 64.2%, respectively, thus was 16.19, 26.37, and 12.2% more than in the cultures carried out at a constant 50% saturation. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2012 相似文献
20.
A double-mutant cell line, which was unable to grow in a medium with NO
3
-
as the sole nitrogen source and was resistant to 5-methyl-tryptophan (5MT), was selected from cell suspensions of Sinapis turgida Del. (Brassicaceae) by culturing the cells in AA medium (Toriyama and Hinata, 1985, Plant Sci. 41, 179–183) supplemented with 50 mM chlorate and 229 M 5MT. Protoplasts of this cell line were fused with mesophyll protoplasts of Brassica oleracea L. with dextran, and six somatic hybrids were selected initially by culture in the NO
3
-
medium and then by transfer to the NO
3
-
medium supplemented with 229 M 5MT. The somatic hybrids produced embryoids, leaves and plantlets on a regeneration medium. The hybrid characters were confirmed by investigations of acid phosphatase (EC 3.1.3.2) and peroxidase (EC 1.11.1.7) isoenzymes, chromosome number, growth on NO
3
-
medium, 5MT resistance, and capacity to regenerate plants. Somatic hybrids between S. turgida Del. and B. nigra (L.) Koch were also obtained using this method. These results indicate that the double-mutant cell line established here will be able to serve as a universal hybridizer to select somatic hybrids after protoplast fusion with any other wild-type partner.Abbreviations B5
medium of Gamborg et al. (1968)
- MS
medium of Murashage and Skoog (1962)
- 5MT
5-thethyltryptophan 相似文献
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