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1.
In vitro cultures of maize (Zea mays L.) endosperm derived from the dent inbred A636 have been maintained in liquid culture using Straus' medium for over six years. We have studied the growth of this tissue in four basic media and various modifications of the organic constituents of these media. Auxins and kinetin did not improve growth rate or degree of cell dispersion and thiamine (0.4 mg/l) was the only vitamin required by this tissue. Growth equal to that in the standard Straus medium and improved cell separation was obtained in a medium containing only inorganic salts, sucrose, and thiamine. Although asparagine was not required when high quantities of NH4NO3 and KNO3 were included, more rapid growth was obtained when 2 g/l of asparagine was added. The simplified medium reported in this paper should facilitate the use of maize endosperm tissue in various studies of metabolism, hormone biosynthesis, etc. 相似文献
2.
A diet medium containing 10% (w/v) sucrose can be inferred to be stressful toDrosophila melanogaster from the increased developmental time and reduced size and fecundity of emerging flies. The metabolic basis for this stress and the genetic response to it are of interest from the point of view of both metabolic regulation and the evolutionary genetics of adaptation to stress. Here the effects of a high-sucrose diet on live weight, total protein, stored lipid and glycogen, and crude activities of 12 enzymes involved in energy metabolism were quantified. Assays were done on a large population ofDrosophila that had been acclimated to the laboratory. A collection of eggs was divided to produce two replicate populations maintained on standard medium and two replicates maintained on high-sucrose medium for 133 generations. At the end of this period, both control and sucrose-selected populations were tested on standard and on high-sucrose medium. Results showed that the immediate effect of the high-sucrose diet (compared to standard medium) for both populations was a reduction in live weight and total protein, and activities of many of the enzymes were also reduced by the sucrose treatment, even after adjusting for the weight effect. Selection resulted in several changes on both the standard and the sucrose medium, but the direction of change was not always the same as the acute effect. In no case was there a significant medium by selection-treatment interaction. The pattern of phenotypic correlations did not resolve the reasons for the direction of the genetic responses. Correlations were generally stable across diets and after selection, but there were notable exceptions. 相似文献
3.
Effect of Conditioning, Betaine, and Sucrose on Survival of Rhizobacteria in Powder Formulations 总被引:1,自引:0,他引:1
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To assess the feasibility of simplified dry formulations of beneficial rhizobacteria with improved shelf life, strains of Pseudomonas and members of the family Enterobacteriaceae were conditioned by either aging, exposure to osmotica, or growth on media amended with sucrose or betaine. Strains thus treated were formulated in 1% methylcellulose and talc, and survival was assessed over 10 to 12 months. Survival of 24-h-old cultures of the same strains suspended in 20% xanthan gum and talc over the same interval was used as the standard of comparison. The survival of strains treated with sucrose, with or without betaine, and formulated in methylcellulose and talc was equal to or greater than that of 24-h-old cultures suspended in 20% xanthan gum and talc. Aging of strains on unamended King's medium B, growth of strains on KCl-amended media, and addition of betaine to KCl-amended King's medium B, whether or not strains were suspended in buffer or a diluent isosmotic to culture conditions, failed to improve survival of the strains tested. The practicality of specific amendments, such as sucrose or other disaccharides, for promoting survival of beneficial bacteria in simplified dry formulations was thus demonstrated. 相似文献
4.
Alison W. Roberts Linda T. Koonce Candace H. Haigler 《Plant Cell, Tissue and Organ Culture》1992,28(1):27-35
A simplified medium has been developed for the differentiation of tracheary elements in suspension cultures of mesophyll cells of Zinnia elegans L. All inorganic salts contained in media used previously were retained in the simplified medium, but most were reduced in concentration. The only organic supplements required for optimum differentiation were thiamine and nicotinic acid, in addition to the plant growth regulators N6-benzylaminopurine and -naphthyleneacetic acid, and sucrose as a carbon source. Mannitol, an osmoticum, was necessary for rapid, synchronous differentiation. This simplified medium is particularly suitable for studies of the role of Ca2+ in tracheary element differentiation due to the elimination of myo-inositol, an intermediate in the phosphatidyl inositol signal transduction pathway and reduction in the concentrations of Mg2+ and Mn2+, which block calcium channels. It is also possible to eliminate EDTA from the medium, enabling studies using specific calcium chelators. Additional culture variables for the optimization of differentiation are discussed.Abbreviation TE
tracheary element 相似文献
5.
A liquid-medium-based protocol for rapid regeneration from embryogenic soybean cultures 总被引:6,自引:0,他引:6
Soybean [Glycine max (L.) Merrill] somatic embryos of the cultivar Jack underwent histodifferentiation in liquid Murashige and Skoog (MS) medium
with 3% maltose, or according to the standard published procedure employing solidified MS media, permitting the recovery of
an average of 8.1 and 3.9 embryos/mg of embryogenic tissue, respectively. Cotyledon-stage embryos that developed in liquid
medium were ready for desiccation within 4 weeks, while the embryos from the standard procedure required a maturation step
for an additional 4 weeks. Comparison of embryo development in MS medium with maltose or FN Lite-based medium without growth
regulators and supplemented with maltose or an equimolar amount of sucrose revealed that sucrose promotes faster embryo histodifferentiation
and maturation, and allows the recovery of up to 50% more mature, cotyledon-stage embryos within 3 weeks. The use of this
liquid-medium-based protocol relative to the standard procedure led to a fourfold increase in the number of cotyledon-stage
embryos recovered from other genotypes tested. In many cases, however, the percent germination was lower. Application of this
new procedure also made it possible to harvest transgenic seed 9 months following biolistic bombardment, as compared to the
13 months required when the standard solid-medium-based protocol was used.
Received: 1 December 1997 / Revision received: 27 April 1998 / Accepted: 20 May 1998 相似文献
6.
There is increasing evidence that the sucrose normally added to the culture medium affects negatively the photosynthetic capacity of plantlets. At the same time, however, sucrose cannot be eliminated from the medium, as it is required for normal in vitro growth. We argue that this is true only under the conventional light conditions of growth-rooms. In the present paper irradiance of growth-rooms was increased 10 times and although the sucrose-inhibitory effect was found at high sucrose concentrations, it was possible to grow coconut (Cocos nucifera L.) plantlets without sucrose. Those plantlets showed both high photosynthetic capacity and comparable in vitro growth to those grown with sucrose in the medium under conventional growth-room irradiance. Nevertheless, the best growth was achieved under mixotrophic conditions where at high irradiance and moderate sucrose concentrations plantlets accumulated 27 % more biomass than plantlets grown without sucrose under high irradiance and 43 and 73 % more biomass than their counterparts at low irradiance with or without sucrose, respectively. 相似文献
7.
M. Ahmad A. G. Fautrier D. L. McNeill G. D. Hill D. J. Burritt 《Plant Cell, Tissue and Organ Culture》1997,47(2):169-176
As an initial step in establishing interspecific hybridization to broaden the genetic basis of lentils [Lens culinaris ssp.culinaris (Medikus) Williams], a set of experiments was carried out to produce an efficient in vitro protocol for propagation of lentil
and two of its wild relatives (Lens ervoides andLens culinaris ssp.orientalis). The objective of the experiments was to optimize the media (Murashige and Skoog) to regenerate shootsin vitro from nodal segments without a callogenic phase. The number of shoots per explant, the number of nodes per shoot and shoot
length showed that species differences, gibberellic acid and benzyladenine levels had the largest effects, with only minor
interaction effects. The experiments therefore identified a standard protocol which gave the optimum levels of growth regulators,
Murashige and Skoog (MS) salts and sucrose concentrations for maximum plant regeneration from the nodal segment of these species.
The medium recommended for optimal shoot regeneration without a callogenic stage contained 2.89 μM GA3 in combination with 1.11 μM BA in MS medium lacking sucrose. The optimal medium for root induction on these shoots had the
MS medium supplemented with 5.37 μM NAA. Final successful establishment of regenerated plants was completed by the transfer
to a third medium containing half-strength MS salts. 相似文献
8.
M. R. Legha K. V. Prasad S. K. Singh C. Kaur A. Arora S. Kumar 《In vitro cellular & developmental biology. Plant》2012,48(1):99-106
In vitro carotenoid pigment production in callus cultures of Calendula officinalis L. was investigated using two basal media, semi-solid versus liquid media and varied concentrations of sucrose, ammonium, and nitrate nitrogen. Of the two explants that were evaluated,
floret explants were best for callus induction using Murashige and Skoog (MS) medium supplemented with 2.0 mg l−1 2,4-dichlorophenoxyacetic acid under complete darkness. Carotenoid pigment induction was significantly augmented when the
sucrose concentration was increased. Low sucrose concentrations in the culture medium deferred the onset of pigment induction
and reduced the overall levels of carotenoid pigments produced. The highest amount of carotenoid pigments was observed when
the callus was grown on the MS medium without ammonium nitrogen. The quantity of carotenoids was slightly elevated in cultures
grown on semi-solid medium than those grown in liquid medium. In vitro carotenoid production was optimized by modifying the concentration of ammonium nitrogen to nitrate nitrogen in the culture
medium and enhancing the sucrose concentration. 相似文献
9.
In vitro-grown shoot tips of apples (Malus domestica Borkh. cv. Fuji) were successfully cryopreserved by vitrification. Three-week-old in vitro apple plantlets were cold-hardened at 5°C for 3 weeks. Excised shoot tips from hardened plantlets were precultured on a solidified Murashige & Skoog agar medium (MS) supplemented with 0.7 M sucrose for 1 day at 5°C. Following preculture shoot tips were transferred to a 2 ml plastic cryotube and a highly concentrated cryoprotective solution (designated PVS2) was then added at 25°C. The PVS2 contains (W/V) 30% glycerol, 15% ethylene glycol and 15% dimethylsulfoxide in medium containing 0.4 M sucrose. After dehydration at 25°C for 80 min, the shoot tips were directly plunged into liquid nitrogen. After rapid warming, the shoot tips were expelled into 2 ml of MS medium containing 1.2 M sucrose and then plated on agar MS medium. Direct shoot elongation was observed in approximately 3 weeks. The average rate of shoot formation was about 80%. This vitrification method was successfully applied to five apple species or cultivars and eight pear cultivars. This method appears to be a promising technique for cryopreserving shoot tips from in vitro-grown plantlets of fruit trees.Abbreviations DMSO
dimethylsulfoxide
- EG
ethylene glycol
- PVS2
vitrification solution
- LN
liquid nitrogen
- BA
6-benzylaminopurine
- NAA
-naphthaleneacetic acid
- SE
standard error
- ABA
abscisic acid 相似文献
10.
I. Morkunas T. Lehmann W. Ratajczak L. Ratajczak B. Tomaszewska 《Acta Physiologiae Plantarum》2000,22(4):389-394
Embryos of pea (Pisum sativum L. cv Sol) deprived of cotyledons were cultured for 3 days in medium with or without sucrose. Respiratory activity of embryos (intact)
as well as the ability to oxidize glutamate by mitochondria isolated from embryos were studied. Respiration of intact embryos
grown in sucrose supplemented medium was more intensive than in the starved ones. Transfer of the starved embryos to the sucrose-containing
medium induced the increase in the intensity of O2 consumption. Mitochondria isolated from both starved and control embryos exhibited respiratory control. Mitochondria isolated
from embryos cultured in the absence of sucrose showed higher (about 60 %) ability to oxidize glutamate and α-ketoglutarate
than mitochondria from embryos grown in sucrose containing medium. The absence of sucrose in the medium led to a rapid increase
in the specific activity of glutamate dehydrogenase (NADH-GDH and NAD-GDH) and it was accompanied by changes in izoenzymatic
pattern of enzyme. These results suggest that in the conditions of sucrose starvation glutamate dehydrogenase may be responsible
for the increase of glutamate oxidation by mitochondria of pea embryos. Electrophoretic separation of glutamate dehydrogenase
isolated from embryos cultured in medium without sucrose showed the presence of ca. 17 isoenzymes while in non-starved embryos only 7 isoenzymes were identified. However, the addition of sucrose to starved
embryos after 24 hours of cultivation led to a decrease in glutamate dehydrogenase activity (up to 40 %) but it did not cause
the changes in isoenzymatic pattern. These results suggest that in the conditions of sucrose starvation glutamate dehydrogenase
maybe responsible for the increase of glutamate oxidation by mitochondria of pea embryos. The posibility of glutamate dehydrogenase
regulation by sucrose is discussed. 相似文献
11.
Human serum albumin (HSA) is the most widely used clinical serum protein. Currently, commercial HSA can only be obtained from
human plasma, due to lack of commercially feasible recombinant protein expression systems. In this study, inducible expression
and secretion of HSA by transformed rice suspension cell culture was established. Mature form of HSA was expressed under the
control of the sucrose starvation-inducible rice α Amy3 promoter, and secretion of HSA into the culture medium was achieved by using the α Amy3 signal sequence. High concentrations of HSA were secreted into culture medium in a short time (2–4 days) by sucrose depletion
after cell concentrations had reached a peak density in culture medium containing sucrose. The recombinant HSA had the same
electrophoretic mobility as commercial HSA and was stable and free from apparent proteolysis in the culture medium. In a flask
scale culture with repeated sucrose provision-depletion cycles, HSA was stably produced with yields up to 11.5% of total medium
proteins or 15 mg/L per cycle after each sucrose provision-depletion cycle. A bubble column type bioreactor was designed for
production of HSA. In the bioreactor scale culture, HSA was produced with yields up to 76.4 mg/L 4 days after sucrose depletion.
HSA was purified from the culture medium to high purity by a simple purification scheme. Enrichment of HSA in culture medium
simplifies downstream purification, minimizes protease degradation, and may reduce production cost. The combination of a DNA
construct containing the α Amy3 promoter and signal sequence, and the use of a rice suspension cell culture can provide an effective system for the production
of recombinant pharmaceutical proteins. 相似文献
12.
Relative importance of maltose and sucrose supplied during a 2-step potato microtuberization process
A 2-stage in vitro tuberization process comprising first micropropagation via nodal explants and then tuber induction in the resultant in vitro plantlets was studied using 2 cultivars of potato, Iwa and Daeji. In particular, the effects on both plantlet growth and
subsequent in vitro tuberization of Murashige and Skoog (1962) basal medium containing either sucrose or maltose, each at 3 % (w/v), used for
micropropagation were investigated. Sucrose and maltose were found to be equally effective in supporting development of vigorous
plantlets from the nodal explants of both potato cultivars. Upon transfer to a medium with an optimised level of sucrose (i.e. 8 %, w/v) for in vitro tuberization, only the plantlets previously grown in the sucrose-containing medium were capable of forming more microtubers
of the larger size category (greater than 0.5 g). The relative importance of sucrose supply at the mircropropagation stage
was further confirmed when the resultant plantlets grown in the 3 % sucrose-containing medium were transferred to an in vitro tuberization medium containing either sucrose or maltose, each at 8 % (w/v). In this experiment, maltose and sucrose had
indistingushable effects on in vitro tuberization. 相似文献
13.
The influence of different sugars (sucrose, maltose, glucose and fructose, 0.05–0.5 M) on embryogenesis and plant regeneration
from cultured anthers of niger [Guizotia abyssinica (L. f.) Cass.] have been studied. Among the different sugars tested, 0.2 M sucrose was the best for embryo induction and
plant regeneration. Maximum of 57 embryos per 60 anthers were induced on embryo induction medium [Gamborg’s B5 medium supplemented
with 10 μM 2,4-dichlorophenoxyacetic acid (2,4-D), 2 μM kinetin (KIN)] containing 0.2 M sucrose. Embryo differentiation was
achieved on B5 medium supplemented with 0.5 μM benzyladenine (BA) and 0.09 M sucrose. Embryo maturation was on B5 medium containing
10 μM abscisic acid (ABA) and 0.09 M sucrose. Embryo germination was achieved on B5 medium with 0.09 M sucrose. Embryos that
were developed on B5 medium supplemented with 0.2 M sucrose showed highest frequency (68 %) of plant regeneration. 相似文献
14.
Jan De Riek Abel Piqueras Pierre C. Debergh 《Plant Cell, Tissue and Organ Culture》1997,47(3):269-278
Uptake and metabolism of sucrose in micropropagatedRosa multiflora using the double layer technique was investigated. In the multiplication as well as the root induction stage, hydrolysis
of sucrose in the culture medium was observed. A mathematical model was developed to quantify sucrose hydrolysis and the uptake
of sucrose, glucose and fructose, based on the time series for the different sugars in the culture medium. These data were
linked to a study of the sugar metabolism in the microshoots. After 48 h of incubation on14C-[U]-glucose containing medium, the incorporated label was mainly detected in the ethanol soluble fraction; within this fraction
sucrose was the most important compound. This indicates a significant re-synthesis of sucrose in the plant material after
the uptake of hexose. To assess the extent that different enzymes of sucrose metabolism (invertases, sucrose synthase and
sucrose-P-synthase) were involved, their activity in different plant parts (of final stage III microshoots) were assayed.
A decreasing gradient for sucrose metabolising enzymes from the roots toward the leaves gave a good indication of how the
different tissues depend on sucrose absorbed from the medium. 相似文献
15.
TheRhizobium tropici strain CFN 299 was maintained on PY medium and was grown in minimal medium (MM) with sucrose, glucose, fructose and glutamate (or their combination) as carbon sources. Bacteria were able to simultaneously use different carbon sources and, with a combination sucrose and glutamate, the growth rate was faster than with either carbon source alone. Sucrose transport was induced by sucrose and partially repressed by glucose and glutamate if they were included in MM as additional carbon sources. The transport of sucrose was active because both an uncoupler (dinitrophenol, DNP) and inhibitors of terminal oxidation (KCN, NaN3) severely reduced sucrose uptake. Sucrose transport was also sensitive to a functional sulfhydryl reagent but was much less sensitive to EDTA and arsenate. We obtained nonlinear Lineweaver-Burk plots for the uptake of sucrose (by sucrose-grown bacteria), and this implied the existence of at least two uptake mechanisms. Invertase (EC 3.2.1.26) is the main enzyme for sucrose hydrolysis in this organism. This enzyme was induced by sucrose and had high activity in mid-log phase cells when sucrose was the sole carbon source (0.2%). Invertase activity was not detected in growth medium. In general, the results obtained support the idea, thatR. tropici is adapted to sucrose utilization and to multicarbon nutrition during its interaction with plants. 相似文献
16.
Summary The effect of the addition of octadecanoylsucrose esters to the growth medium on the production of inulinase by Aspergillus niger SL-09 was studied in batch culture using shake flasks. The activities of inulinase in vitro and in vivo formed by Aspergillus niger SL-09 was enhanced dramatically by the addition of sucrose ester S-770 to the medium, and it was confirmed that sucrose ester
acted as a very efficient inducer for inulinase production. As a result, with the addition of 6 g sucrose ester l−1 at the beginning of the culture, the enzyme activities were enhanced near 7-fold higher than that obtained in the basal medium. 相似文献
17.
Marcel H. N. Hoefnagel Kees R. Libbenga Linus H. W. van der Plas 《Plant cell reports》1994,13(8):464-467
Summary The uptake of glucose and fructose from the medium by Catharanthus roseus cell suspensions was strongly inhibited by high medium salt concentration, such as found in LS (Linsmaier and Skoog 1965) medium. After inoculation into standard LS nutrient medium with less than 5 mM hexose no uptake occurred, while in low salt medium hexose was completely depleted. At a hexose concentration of 50 mM the uptake rate was higher in low salt medium than in standard medium. The lower rate of uptake at high salt concentration was not the result of a pH or osmotic effect of the salts. Probably the affinity of the hexose carrier is affected by the ion concentration of the medium. The decrease in medium salt concentration during normal batch culture probably will have a considerable effect on hexose uptake.Abbreviations LS
Linsmaier and Skoog
- S
sucrose
- N
mineral nitrogen
- K
K2SO4
- F
fructose 相似文献
18.
The particle gun approach was used for the quantification of promoter efficiency in a test system for transient gene expression.
β-Glucuronidase was used as reporter gene for determining promotote strength. The variability inherent in this gene transfer
system was considerably reduced by calculating a transformation efficiency factor given by the expression of a cotransferred
second reporter gene (firefly luciferase). The calibration of β-glucuronidase activity by the transformation efficiency factor
caused a lower statistical variance of the values and allowed reliable results to be obtained with a smaller set of repetitions.
The CaMV 35S promoter (as a control) and the monocot-specific promoters for maize polyubiquitin1, rice actin 1 and the maize-derivedEmu were characterized and compared with respect to expression strength, as tested under identical conditions in suspension cell
cultures of maize, barley and tobacco. Compared to the 35S promoter, the monocot-specific promoters show up to 15-fold higher
expression in maize and barley but give only weak expression in tobacco. No expression was found for the rice actin 1 promoter
in tobacco. The level of reporter gene expression is influenced by the osmotic potential in the agar medium. For theEmu promoter, the calibrated β-glucuronidase activities remained mearly constant at low sucrose concentrations. Above 8% sucrose,
the calibrated activities increased steadily with increasing osmotic conditions, reaching a three-to four-fold higher level
at the highest sucrose concentration (32%) as compared to the standard concentration (4% sucrose) in the medium. 相似文献
19.
Both somatic and excised zygotic embryos of interior spruce (Picea glauca engelmannii complex) required exogenous sucrose in the medium for germination in vitro. Over a period of 29 days on sucrose-containing medium germinants with roots and epicotyls developed from both kinds of embryo, and their content of linolenic acid (9,12,15-18:3) increased about six- to eightfold. Without added sucrose, embryos showed retarded growth or were necrotic, and the content of linolenic acid was barely detectable in their fatty acid profiles. Through14C-sucrose uptake studies, it was determined that germinants consumed only 25% of the sucrose available in a 1% (wt/vol) sucrose-containing medium. Since no radiolabelled fatty acids were detected, it appears that externally supplied sucrose was not used in the synthesis of lipids. Although sucrose was present during plantlet development, 72% of the initial lipids were consumed. To some extent, the plantlets appeared to be obligate storage lipid utilizers.Abbreviations 2,4-D
2,4-Dichlorophenoxyacetic acid
-
FAMEs
Fatty acid methyl esters
-
HPLC
High-performance liquid chromatography 相似文献
20.
`Isubgol', the mucilaginous husk derived from the seeds of Plantago ovata, was successfully used as a gelling agent in tissue culture media for in vitro seed germination, shoot formation and rooting
in Syzygium cuminii and anther culture in Datura innoxia. For seed germination, Knop's basal medium supplemented with 1% sucrose was employed, whereas for the development of shoots
the epicotyl segments excised from in vitro-developed seedlings were cultured on MS basal medium supplemented with 4% sucrose
and 1 mg/l 6-benzyladenine. Shoots that developed from the epicotyl segments were rooted on Knop's medium enriched with 2%
sucrose and 1 mg/l indole-3-acetic acid. The anthers of D. innoxia excised at the late uninucleate to early binucleate stages of microspore development were cultured on Nitsch's basal medium
containing 2% sucrose. Media were either gelled with 0.9% agar or 3% `Isubgol'. The response on media gelled with `Isubgol'
in each of the cases was similar to that on media solidified with agar.
Received: 9 October 1996 / Revision received: 22 July 1996 / Accepted: 30 July 1997 相似文献