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1.
A survey of the distribution of elastinolytic potential among 32 culture collection isolates ofAspergillus flavus, A. oryzae, A. parasiticus, A. sojae, A. nomius, andA. tamarii revealed this character to be highly conserved withinAspergillus SectionFlavi. Furthermore, 144 isolates ofA. flavus from environmental samples from six separate regions of the United States produced elastase on solid medium. Most previously described polymorphisms in elastinolytic potential were attributed to the toxicity of borate buffers. Replacement of borate with HEPES (N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid) resulted in detection of elastase production on solid medium by all tested fungal isolates except two that had been in culture over 50 years. In liquid culture, only isolates ofA. flavus, A. tamarii, andA. oryzae accumulated elastase activity. Although isoelectric focusing revealed only one isoform (pI 9.0) of elastase in these culture filtrates, elastinolytic activity in filtrates was partially inhibited by both 1,10-phenanthrolene (2 mM) and phenylmethylsulfonylfluoride (2 mM), suggesting the presence of both metallo and serine elastinolytic proteinases.Abbreviation IEF isoelectric focusing The US Government's right to retain a non-exclusive, royalty-free licence to any copyright is acknowledged.  相似文献   

2.
In this study, morphological alterations, biomass growth, and secondary metabolite production of genetically transformed hairy roots ofPanax ginseng C. A. Meyer, were evaluated after administration of plant growth regulators. The addition of benzylamino purine and kinetin to the culture media increased biomass formation and phenolic compound biosynthesis in the hairy roots. α-Naphthaleneacetic acid and indole-3-butyric acid inhibited hairy root growth, however, low concentrations of indole-3-acetic acid slightly increased hairy root growth. Low concentrations of 2,4-Dichlorophenoxyacetic acid profoundly inhibited growth of hairy roots. The addition of plant growth regulators, such as auxin, did not increase total phenolic compounds in hairy roots that did not contain gibberellic acid and cytokinins. Callus formation was induced in cultures suspended in liquid medium amended with benzylamino purine and kinetin. Hairy roots regenerated from these calluses exhibited an active growth pattern with extensive lateral branching in non-amended medium, similar to the growth pattern of the original hairy roots.  相似文献   

3.
Summary Elicitation of sesquiterpenoid aldehyde phytoalexins inGossypium arboreum cell suspension cultures was confirmed by thin layer chromatography, high performance reverse phase liquid chromatography, and an aniline-reaction assay after inoculation with heat-treated conidia ofVerticillium dahliae A 2.3X mean increase in total terpenoids was observed. Component phytoalexins varied, with either hemigossypol and gossypol being detected or the O-methylated terpenoids hemigossypol-6-methyl ether and related compounds. Long-termGossypium suspension cultures were mixoploid with an increase in chromosome number and mean DNA content. Addition ofV. dahliae elicitor(s) to the medium for embryo-proliferating callus ofG. hirsutum inhibited growth and embryo production with a linear correlation (r=−0.87;P<0.01) between the elicitor concentration and the number of embryos. Addition of14C-labeled NaOAc to suspension cells gave 30% incorporation, and from13C-NaOAc addition, labeled sesquiterpenoid aldehydes were recovered. The cotton-Verticillium system is another case of secondary metabolite elicitation in plant tissue culture and might be used for basic studies of hostpathogen interaction as well as for a selection tool to obtain resistance to an important disease.  相似文献   

4.
Jasmonates enhance the expression of various genes involved in terpenoid indole alkaloid (TIA) biosynthesis in Catharanthus roseus. We applied precursor feeding to our C. roseus suspensions to determine how methyl jasmonate (MJ) alters the precursor availability for TIA biosynthesis. C. roseus suspensions were induced with MJ (100 μM) on day 6 and fed loganin (0.30 mM), tryptamine (0.15 mM), loganin plus tryptamine, or geraniol (0.1–1.0 mM) on day 7. While MJ increased ajmalicine production by 3-fold, induced cultures were still limited by terpenoid precursors. However, both induced and non-induced cultures became tryptamine-limited with excess loganin. Geraniol feeding also increased ajmalicine production in non-induced cultures. But MJ appeared to increase geraniol availability in induced cultures, due presumably to the increased expression of Dxs with MJ addition.  相似文献   

5.
The activities of proteinases in the culture fluid and cellular fractions ofBacillus intermedius 3–19 grown under various conditions were studied. Thiol-dependent serine proteinase was the prevalent enzyme in the total pool of extracellular proteinases (70%); its catalytically active form was also detected in the cell membrane and, during active enzyme production, in the cell wall. Another enzyme, glutamyl endopeptidase (10% of the total pool), was detected in the cell membrane; it was also found in the cell wall and cytoplasm during active enzyme secretion into the growth medium. The production of these enzymes was maximal on medium containing inorganic phosphate and gelatin and decreased 2-to 4-fold on medium with glucose and lactate. The level of activity of extracellular enzymes correlated with that of corresponding membrane-bound proteins. The addition of C0Cl2 (2 mM) into the medium caused an essential increase in extracellular glutamyl endopeptidase activity and promoted the release of the membrane-bound enzyme into the culture fluid. Proteolytic activity towards casein was also detected in the cytoplasm. The proteinases localized in the cytoplasm were shown to differ in their properties from those secreted.  相似文献   

6.
Coleus forskohlii hairy root cultures were found to produce forskolin and rosmarinic acid (RA) as the main metabolites. The growth and RA production by C. forskohlii hairy root cultures in various liquid media were examined. The hairy root cultures showed good growth in hormone-free Murashige and Skoog medium containing 3% (w/v) sucrose (MS medium), and Gamborg B5 medium containing 2% (w/v) sucrose (B5 medium). RA yield reached 4.0 mg (MS medium) and 4.4 mg (B5 medium) after 5 weeks of culture in a 100 ml flask containing 20 ml of each medium. Hairy root growth and RA were also investigated after treatment with various concentrations of yeast extract (YE), salicylic acid (SA) and methyl jasmonic acid (MJA). RA production in a 100 ml flask containing 20 ml B5 medium reached 5.4 mg (1.9 times more than control) with treatment of 0.01 or 1% (w/v) YE, 5.5 mg (2.0 times more than control) with treatment of 0.1 mM SA, and the maximum RA content with 9.5 mg per flask (3.4 times more than control) was obtained in the hairy roots treated with 0.1 mM MJA. These results suggest that MJA is an effective elicitor for production of RA in C. forskohlii hairy root cultures.  相似文献   

7.
Summary The feasibility of using plant cell culture to measure toxicity was determined by investigating the toxicological effects of three chemical compounds, allyl alcohol, propargylglycine, and cadmium chloride, on cell cultures ofCatharanthus roseus G. Don (Madagascar periwinkle). Suspension cultures ofC. roseus were maintained in modified B5 medium and transferred every 5 d. Five-day-old cell cultures were exposed to various concentrations (10,3,1,0.3,0.1,0.03,0.01,0.003,0.001,0.0003,0.0001, 0.00003, and 0.0 mM) of the toxicants in both acute and chronic toxicity tests. In the acute test, cells were exposed to the toxicant for 24 h, washed three times with sterile medium, and plated in petri plates with an equal volume of 1.4% agar medium. Cells in the chronic test were plated with an equal volume of 1.4% agar medium containing various concentrations of the toxicant. Cells were incubated 28 d at 30°C in the dark. The colonies were counted and the results plotted as percent survival versus toxicant concentration. The results indicate, at the concentrations tested, thatC. roseus assay may be feasible in that it fulfills the criteria for a practical assay (e.g., rapid, simple, quantifiable, and reproducible). This work was submitted to the faculty of Miami University in partial fulfillment of the requirements for the degree of Master of Environmental Science, Institute of Environmental Sciences.  相似文献   

8.
The Madagascar periwinkle (Catharanthus roseus) produces numerous indole alkaloids, several of which have an important pharmaceutical uses such as ajmalicine, vinblastine and vincristine. The relationship between hypoxia and ajmalicine production in a cell suspension culture of C. roseus were investigated during the cycle of cell culture, in correlation with the effects on growth. The results show that the lack of oxygenation in C20D cells provokes a very strong inhibition in accumulation of the alkaloids and of other possible substances. Moreover, the addition of loganin, a metabolic intermediate of the biosynthetic pathway, in the culture medium of cells subjected to hypoxia restored the alkaloid production. Also, the results showed that the addition of benzyladenine (BA) to the culture medium increased the ajmalicine production and that the inhibitory effect of hypoxia was almost absent in these conditions. Therefore, it could be suggested that BA can without doubt decrease the effects of the hypoxia and increase the ajmalicine production in periwinkle cell suspensions.  相似文献   

9.
Two strains of Agrobacterium rhizogenes (15834, LBA 9402) and one Agrobacterium tumefaciens strain [GV 3101 (PMP90RK, p35SGUS-2)] and four culture media were tested and compared for their ability to induce hairy root formation on wounded Papaver somniferum L. hypocotyls. Five weeks after the infection with A. rhizogenes LBA 9402, hairy roots appeared on 80% of the hypocotyls maintained in the hormone-free liquid medium. Six hairy-root cultures were established. Transformation was confirmed by polymerase chain reaction analysis. One clone was analysed for its alkaloid production. The total alkaloid content was higher in the transformed roots (0.46±0.06% DW) than in the untransformed roots (0.32±0.05% DW). The transformed roots accumulated three times more codeine (0.18±0.02% DW) than intact roots (0.05±0% DW). Moreover, morphine (0.255±0.03% DW) and sanguinarine (0.014±0% DW) were found in the liquid culture medium.Abbreviations 2,4-D 2,4-Dichlorophenoxyacetic acid - LS Linsmaier and Skoog  相似文献   

10.
Hairy roots ofCatharanthus roseus obtained by co-cultivation of hypocotyl segments withAgrobacterium rhizogenes, and cultured in SH (Schenk and Hildebrandt) basal medium, formed two types of calli when subcultured in SH medium with 1 mg/1 -naphthaleneacetic acid and 0.1 mg/l kinetin. One of them, a compact callus, when re-subcultured in SH basal medium gave rise to hairy roots again. A rhizogenic cell suspension culture was established from this type of callus. When cultured in SH medium with growth regulators, the rhizogenic callus produced catharanthine at a level of 41% of the level in the initial hairy roots. Upon transfer to SH basal medium, regenerated hairy roots produced this alkaloid at the original level of 1.5 mg/g dry wt. Using this cell/hairy root interchange system a new management system for hairy root culture in bioreactors has been devised and examined involving production of biomass in the form of a cell suspension in medium supplemented with growth regulators, and catharanthine production by hairy roots regenerated from these cells in medium without growth regulators.Abbreviations NAA -naphthaleneacetic acid - SH Schenk and Hildebrandt - SHNK SH medium + 1 mg 1–1 NAA + 0.1 mg 1–1 kinetin  相似文献   

11.
Mannheimia succiniciproducens MBEL55E isolated from bovine rumen is able to produce a large amount of succinic acid in a medium containing glucose, peptone, and yeast extract. In order to reduce the cost of the medium, whey and corn steep liquor (CSL) were used as substrates for the production of succinic acid by M. succiniciproducens MBEL55E. Anaerobic batch cultures of M. succiniciproducens MBEL55E in a whey-based medium containing CSL resulted in the production of succinic acid with a yield of 71% and productivity of 1.18 g/l/h, which are similar to those obtained in a whey-based medium containing yeast extract (72% and 1.21 g/l/h). Anaerobic continuous culture of M. succiniciproducens MBEL55E in a whey-based medium containing CSL resulted in a succinic acid yield of 69% and a succinic acid productivity as high as 3.90 g/l/h. These results show that succinic acid can be produced efficiently and economically by M. succiniciproducens MBEL55E from whey and CSL.  相似文献   

12.
Mycelium ofBeauveria bassiana can be grown in liquid culture, filtered, and the mycelium dried. After rehydration the mycelium sporulates. Two carbohydrate sources (sucrose and maltose), and one nitrogen/vitamin source (yeast extract) were tested for mycelium growth and subsequent conidial production. Maximum mycelium growth (12.31 mg/ml), in liquid culture, was in the sucrose (3.5%)/yeast extract (3.5%) medium, but mycelium from a maltose (2%)/yeast extract (0.75%) medium produced the maximum of 4.62×106 conidia/mg dry mycelium after incubation in moist Petri dishes. Using the data on mycelium yield (in liquid culture) and conidial production (by dry mycelium) it is calculated that the sucrose (3.5%)/yeast extract (3.5%) and the maltose (2%)/yeast extract (0.75%) media produce most conidia per media volume (an equivalent of 3.52–3.72×107 conidia/ml).   相似文献   

13.
Embryogenic callus in Catharanthus roseus was initiated from hypocotyl on Murashige and Skoog’s (MS) medium supplemented with 1.0–2.0 mg dm−3 of 2,4-dichlorophenoxyacetic acid (2,4-D) or chlorophenoxyacetic acid (CPA). Calli from other sources were non-embryogenic. Numerous somatic embryos were induced from primary callus on MS medium suplemented with naphthalene acetic acid (NAA) within two weeks of culture. Embryo proliferation was much faster on medium supplemented with 6-benzylaminopurine (BAP). After transfer to medium with gibberellic acid (GA3, 1.0 mg dm− 3) mature green embryos were developed and germinated well into plantlets on MS liquid medium supplemented with 0.5 mg dm−3 BAP. Later, embryos with cotyledonary leaves were subjected to different auxins treatments for the development of roots. Before transfer ex vitro, plantlets were cultivated on half strength MS medium containing 3 % sucrose and 0.5 mg dm−3 BAP for additional 2 weeks. Additionally, the effect of liquid medium has been evaluated at different morphogenetic stages.  相似文献   

14.
Cytosolic Ca2+ and jasmonate mediate signals that induce defense responses in plants. In this study, the interaction between Ca2+ and methyl jasmonate (MJ) in modulating defense responses was investigated by monitoring ajmalicine production in Catharanthus roseus suspension cultures. C. roseus suspensions were treated with nine combinations of CaCl2 (3, 23, and 43 mM) and MJ (0, 10, and 100 μM) on day 6 of growth. Increased Ca2+ influx through the addition of extracellular CaCl2 suppressed ajmalicine production in MJ-induced cultures. The highest ajmalicine production (4.75 mg/l) was observed when cells were treated with a low level of calcium (3 mM) combined with a high level of MJ (100 μM). In the presence of 3 mM CaCl2 in the medium, the addition of Ca2+ chelator EGTA (1, 2.5, and 5 mM) or Ca2+ channel blocker verapamil (1, 10, and 50 μM) to MJ-induced (100 μM) cultures on day 6 also inhibited ajmalicine production at higher levels of the Ca2+ inhibitors. Hence, ajmalicine production in MJ-induced C. roseus cultures depended on the intracellular Ca2+ concentration and a low extracellular Ca2+ concentration (3 mM) enhanced MJ-induced ajmalicine production.  相似文献   

15.
Summary A stabilized two-year old suspension of a Datura innoxia cell line, producing small amounts of tropane alkaloids (scopolamine and hyoscyamine) was used in this study. Calcium alginate immobilization has been shown to be able to increase secondary metabolite (i. e. alkaloid) production. The effects of calcium and ungellified alginate were both beneficial for tropane alkaloid synthesis; a 10mM calcium chloride supply gave the best results, with a 10-fold yield increase.Abbreviations 2,4-D 2,4-dichlorophenoxyacetic acid - S standard cell culture medium - HPLC high performance liquid chromatography - FW fresh weight - FDA fluorescein diacetate - FW fresh weight  相似文献   

16.
The cultural characteristics of the fungusCladosporium phlei were assessed in order to develop an improved method for the production of the fungal pigment, phleichrome, which is an intermediate in the production of a photodynamic therapeutic agent. The growth ofC. phlei, as measured by the hyphal growth rate and increase in biomass, varies significantly depending on the culture media utilized (V8 juice-based medium proved optimal for both growth rate and biomass increase). How-ever, even on a V8 juice plate, the growth ofC. phlei occurred slowly and in a limited fashion, in that the colony covered only 75% of the agar surface after more than 4 weeks of cultivation at 20°C. Supplementations of glucose, fructose, galactose, and sucrose increased both hyphal expansion and mass production, whereas supplementations of other carbon sources, including glycerol and sorbitol, exerted no detectable effects. The effect of inorganic nitrogen supplementation was negligible, whereas organic nitrogen evidenced significant effects, with enhanced growth with malt extract and growth inhibition with yeast extract and tryptone. Sporulation was enhanced under conditions of continuous light, and a minimum of 103 spores per mL of liquid media was found to be necessary for the optimal mass increase. A simple extraction procedure was established in order to isolate the deep red pigment which was subsequently identified as phleichrome via NMR analysis. WhenC. phlei was cultured on V8 medium containing 5% glucose and 2% malt extract, the quantity of mycelial mass was estimated as 20.6 g (dry weight) per liter of culture. The expected phleichrome yields from the mycelia and culture filtrates were estimated to be 43 and 2 mg/L, repectively. There was an equal contribution of the reported research by the first two authors.  相似文献   

17.
W. Noé  J. Berlin 《Planta》1985,166(4):500-504
Tryptophan decarboxylase (EC 4.2.1.27) is synthesized de-novo by Catharanthus roseus cells shortly after the cells have been transferred into culture medium in which monoterpenoid indole alkaloids are formed. The enzyme production, monitored by in-vivo labelling with [35S]methionine and immunoprecipitation, precedes the apparent maximal enzyme activity by 10–12 h. From the time course of the descending enzyme activity after induction, a half-life of 21 h for tryptophan decarboxylase in C. roseus cell suspensions is calculated. A comparison of the polyadenylated-RNA preparations from C. roseus cells indicates that mRNA activity for tryptophan decarboxylase is only detected in cells grown in the production medium. The importance of tryptophan decarboxylase induction with respect to the accumulation of th corresponding alkaloids is discussed.Abbreviation TDC tryptophan decarboxylase  相似文献   

18.
A cultivation system with simultaneous growth of six bacterial cultures in separate bags in dialysis culture was developed. In a medium with no added carbon source (one half concentrated Hoagland solution, water deionized and distilled), cell number ofRhizobium japonicum increased during a 7 day period by a factor of 35, whereas the number ofEnterobacter aerogenes cells decreased to one half. With a concentration of 100 nM succinate as an additional carbon source in the inflow,Rhizobium japonicum 61-A-101 cell number increased by a factor of 50 during an 8 day period, whereas cell number ofEnterobacter cloacae NCTC 10005 only doubled and ofEnterobacter aerogenes NCTC 10006 decreased. At 10 mM concentration of succinate in the inflow, doubling time the twoEnterobacter strains was about 12 h, compared to about 24 h for theRhizobium japonicum strain. Varying the succinate concentration from 10 mM to 100 nM in the inflow,Rhizobium japonicum 61-A-101 surpassed theEnterobacter aerogenes strains in the growth rate between 1 mM and 100 M succinate in the inflowing medium. Three otherRhizobium japonicum strains (fix+ and fix-) did grow with a similar rate as strain 61-A-101 at very low concentrations of substrate. Growth rates for the strains were confirmed by protein data per culture. Growing in competition with twoPseudomonas strains,Rhizobium japonicum RH 31 Marburg (fix-) did overgrow alsoPseudomonas fluorescens, was however outgrown byPseudomonas putida. In utilizing low concentrations of a14C labelled organic acid (malonate), three strains ofRhizobium japonicum left 2–4 times smaller amounts of14C in the medium than two species ofPseudomonas and two species ofArthrobacter.On sabbatical leave at ANU  相似文献   

19.
Indole compounds secreted byFrankia sp. HFPArI3 in defined culture medium were identified with gas chromatography-mass spectrometry (GC-MS). WhenFrankia was grown in the presence of13C(ring-labelled)-L-tryptophan,13C-labelled indole-3-acetic acid (IAA), indole-3-ethanol (IEtOH), indole-3-lactic acid (ILA), and indole-3-methanol (IMeOH) were identified.High performance liquid chromatography (HPLC) and GC-MS with selected ion monitoring were used to quantify levels of IAA and IEtOH inFrankia culture medium. IEtOH was present in greater abundance than IAA in every experiment. When no exogenous trp was supplied, no or only low levels of indole compounds were detected.Seedling roots ofAlnus rubra incubated in axenic conditions in the presence of indole-3-ethanol formed more lateral roots than untreated plants, indicating that IEtOH is utilized by the host plant, with physiological effects that modify patterns of root primordium initiation.  相似文献   

20.
Cultivating Vitis vinifera cell suspensions in a production medium which is characterized by high sucrose and low nitrate concentrations (132 mM and 6.25 mM respectively) repressed growth but enhanced the intracellular accumulation of anthocyanins, especially peonidin 3-glucoside. Increasing the ammonium concentration of the production medium from 2 to 8–16 mM increased growth and decreased the accumulation of anthocyanins and peonidin 3-glucoside specifically. Instead, peonidin 3-p-coumaroylglucoside accumulated. At 24 mM ammonium concentration, growth was inhibited and accumulation of peonidin 3-p-coumaroylglucoside was significant (p<0.05) and represented 42% of total anthocyanins after 12 days of culture compared with 19% in the production medium with 2 mM ammonium.Contribution Number 217.  相似文献   

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