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1.
The effects of eight microelements (I, BO3 3–, MoO4 2–, Co2+, Cu2+, Mn2+, Fe2+, Zn2+) on the biosynthesis of camptothecin and the growth of suspension cultures of Camptotheca acuminata were studied. The increase of I to 25 M l–1, Cu2+ to 1 M l–1, Co2+ to 2 M l–1 and MoO4 2– to 10 M l–1 in Murashige and Skoog (MS) medium resulted in 1.66, 2.84, 2.53 and 2.04 times higher of camptothecin yield than that in standard MS medium respectively. Combined treatment of I (25 M l–1), Cu2+ (1 M l–1), Co2+ (2 M l–1) and MoO4 2– (10 M l–1) lead to improve cell dry weight, camptothecin content, and camptothecin yield to 30.56 g l–1, 0.0299%, and 9.15 mg l–1, respectively, which were 20.2, 208.9 and 273.8% increment respectively when compared with those of control.  相似文献   

2.
The biomass and production (thymidine incorporation) of heterotrophic bacterioplankton has been assessed from July, 1988, to October, 1989. in Lake Xolotlán, Nicaraqua. Bacterial abundance was high, 2–3.1010 cells.l–1, and bacterial biomass averaged ca. 0.75 mg C.l–1, or roughly 20% of the partivculate organic carbon. Bactrial production averaged between 3.5–5 g C.l–1.h–1 and on a areal basis was 650–959 mg C.m–2.d–1 or 13–20% ofthe primary production. Although bacterial production (volumetric basis) was typical for eutrophic lakeks, the bacterial specific growth rate was low, the bacteial population doubling time was ca. 1 week, perhaps indicating that there was a low grazing pressure on the bacteria.  相似文献   

3.
Supplementation with CaCl22H2O (40 mg l–1) or CuSO45H2O (10 mg l–1) improved vancomycin production by Amycolatopsis orientalis by 12 and 11%, respectively; used in combination, they acted synergistically. Ca2+ decreased the intracellular concentration of vancomycin 36%, whereas Cu2+ increased the intracellular activity of TDP-glucose:aglycosylvancomycin glucosyltransferase 3 times more than control. Ca2+ probably works by altering the permeability of cells to vancomycin, whereas Cu2+ increases the activity of an enzyme responsible for vancomycin biosynthesis.  相似文献   

4.
Aspergillus fumigatus removed uranium(VI) very rapidly and reached equilibrium within 1 h of contact of biomass with the aqueous metal solution. Biosorption data fitted to Langmuir model of isotherm and a maximum loading capacity of 423 mg U g–1 dry wt was obtained. Distribution coefficient as high as 10,000 (mg U g–1)/(mg U ml–1) at a residual metal ion concentration of 19 mg l–1 indicates its usefulness in removal of uranium(VI) from dilute waste streams. Optimum biosorption was seen at pH 5.0 and was independent of temperature (5–50°C ). Initial metal ion concentration significantly influenced uptake capacity which brought down % (w/w) uranium(VI) removal from 90 at 200 mg U l–1 to 35 at 1000 mg U l–1. Presence of 0.84 mmol Fe2+, Fe3+, Ca2+ and Zn2+ had no effect on uranium(VI) biosorption unlike Al3+ (0.84 mM) which was inhibitory.  相似文献   

5.
Su H  Wang Z  Tan T 《Biotechnology letters》2003,25(12):949-953
The adsorption capacity for Ni2+ on to the surface molecular imprinting adsorbent on Penicillium chysogenum mycelium (the surface-imprinted adsorbent) was 40–45 mg g–1 (using 200 mg Ni2+ l–1), two times of the mycelium adsorbent. The surface-imprinted adsorbent had good stability at pH 28. The optimal concentration of EDTA for desorption was 0.1 to 0.5 g l–1. The surface imprinted adsorbent could be reused 15 times without losing its uptake.  相似文献   

6.
A simple protocol was developed for plantlet regeneration from seedling leaf segments of pigeonpea cultivar ICPL 93115 through shoot organogenesis. Ten-day-old seedlings aseptically grown on MS medium were used for furnishing leaf segments. Initial incubation for 5 days in dark at 25±2 °C followed by transfer to 10/14-h light / dark cycle (12.1 mol photons m–2 s–1) favoured regeneration. The decisive role of 6-benzyl adenine at different concentrations was established on shoot organogenesis. Murashige and Skoog's (MS) (1962) medium fortified with BA of 5.0 mg l–1 was optimum for shoot regeneration and MS + BA of 1.0 mg l–1 for shoot elongation, while MS + IAA (1.0 mg l–1) + kinetin (0.1 mg l–1) showed good results for rooting.  相似文献   

7.
In Taxus cuspidata callus, vanadyl sulfate (10 mg l–1) induced a high (146 g g–1 dry wt) production of 10-deacetylbaccatin III in comparison to 7 g g–1 dry wt of the control. The content of paclitaxel in this species increased from 16 g g–1 to 74 g g–1 dry wt when 20 mg phenylalanine l–1 was used. In T. media, p-aminobenzoic acid induced the highest content of 10-deacetylbaccatin III (481 g g–1 dry wt) versus 181 g g–1 in the control. Paclitaxel increased from 89 to 139 g g–1 dry wt after adding chitosan (20 mg l–1) to the cultures.  相似文献   

8.
Certain yeast cells on solid nutrient medium produced colonies surrounded by a light zone of selenite absorption. This screening procedure resulted in the selection of 22 strains out of 200 isolates with different Se4+-absorbing capacity ranging from 16 to 98.8 g Se4+ g–1 l–1 h–1. The highest rate of Se4+ elimination from the Na2SeO3 solution was observed with an oval shaped, cream pigmented fermentative yeast, tentatively called Candida sp. strain MS4. This strain was isolated from wastewater and found to accumulate selenium oxyanions. Se4+ uptake involved both inactive and active phenomena. The amounts of selenium (initial concentration 2 mg Se4+ l–1) removed from aqueous solution by inactive and active phenomena were 667 g Se4+ g–1 l–1, and 1580 g Se4+ g–1 l–1, respectively. The strain also removed selenate inactively (135 g Se6+ g–1 l–1).  相似文献   

9.
Summary The effect of ancymidol concentration on the development of haploid asparagus embryos was determined. Liquid cultures from anther-derived calli were grown for three weeks in MS medium plus 1.0 mg l–1 2,4-D, 0.1 mg l–1 NAA, 0.2 mg l–1 kinetin, 800 mg l–1 glutamine, 500 mg l–1 casein hydrolysate, 2% sucrose and 0.0–1.0 mg l–1 ancymidol. Cell clumps (224–500 m) were plated on solid embryo maturation medium (MS medium plus 3% sucrose, 0.1 mg l–1 NAA, 0.5 mg l–1 kinetin and 0.0–1.0 mg l–1 ancymidol) and grown for eight weeks. Ancymidol enhanced embryo maturation and germination and was more critical in the solid than liquid medium. Total embryo number did not vary among most treatments. The best response was observed when ancymidol concentrations were 0.1 and 0.5 mg l–1 in the liquid and solid media, respectively; two-thirds of the embryos produced were bipolar and 35% of bipolar embryos germinated. Seven to 82% of plants recovered from different ancymidol treatments were haploid; the others were diploid, triploid or chimeric for ploidy level.Abbreviations NAA naphthaleneacetic acid - 2,4-D 2,4-dichlorophenoxyacetic acid - GA3 gibberellic acid - MS Murashige and Skoog (1962)  相似文献   

10.
Cell suspension cultures of Agave amaniensis and Costus speciosus were grown in media containing Cd2 + up to 25 and 20 mg l–1, respectively, and Pb2+ up to 40 mg l–1. The cultures hyper-accumulated Cd2+ up to 900 and 530 g g–1 and Pb2+ up to 1390 and 1170 g g–1 dry wt. in their respective biomasses. Increasing Pb2+ up to 30 mg l–1 increased the biomass production and total sitosterol content of Costus speciosus by up to 1.7- and 1.3-fold, respectively.  相似文献   

11.
The production of erythritol and the erythritol yield from glucose by Torula sp. were improved, in increasing order, by supplementing with 10 mg MnSO44H2O l–1, 2 mg CuSO45H2O l–1, and both 10 mg MnSO44H2O l–1 and 2 mg CuSO45H2O l–1. Mn2+ decreased the intracellular concentration of erythritol, whereas Cu2+ increased the activity of erythrose reductase in cells. These results suggest that Mn2+ altered the permeability of cells, whereas Cu2+ increased the activity of erythrose reductase in cells.  相似文献   

12.
Viable protoplasts of Vigna sublobata L. were isolated enzymatically from hypocotyls of axenic seedlings. Protoplast yields were dependent upon seedling age, with maximum yields (2.25 ± 0.35 × 106 g fwt–1) from seedlings aged 6 d. Protoplasts regenerated cell walls and underwent sustained divisions when cultured in either agarose-solidified or liquid K8P medium. The plating density affected the division frequency and plating efficiency; the division frequency (68 ±0 6.0%) was maximum at 4.0 × 104 ml–1 while plating efficiency was maximum (1.3 ± 0.1%) at 5.0 × 104 ml–1. Dividing protoplasts developed into microcalli, which produced glossy green compact nodular calli on transfer to 8.0 gl–1 w/v agar-solidified medium containing MS salts, B5 organic components, 30 g l–1 sucrose, NAA (0.2–0.5 mg l–1), zeatin riboside (0.5–2.0 mg l–1) and GA3 (0.5–1.0 mg l–1). These calli, after sub-culture on the same medium, produced shoot buds which underwent elongation following transfer of tissues to 6.0 g l–1 agar-solidified B5 medium containing 30g l–1 sucrose, IBA (0.01 mg l–1) and BAP (1.0 mg l–1). Elongated shoots developed roots after transfer to 8.0g l–1 agar-solidified, hormone-free MS medium with 30 g l–1 sucrose.Abbreviations IAA indole-3-acetic acid - IBA indole-3-butyric acid - BAP 6-benzyladenine or benzylaminopurine - B5 medium after Gamborg et al (1968) - 2,4-D 2,4-dichlorophenoxyacetic acid - GA3 gibberellic acid - 2,i-P 6-(--dimethylallylamino) purine - MS medium after Murashige and Skoog (1962) - NAA 1-naphthaleneacetic acid  相似文献   

13.
A procedure for rapid in vitro multiplication of Tylophora indica (Burm. f.) Merrill., an important indigenous medicinal plant, has been developed. Addition of ascorbic acid was essential to induce sprouting of axillary buds. Optimum multiplication was observed on MS medium containing 6-benzylamino purine (5.0 mg l–1), -naphathalene-acetic acid (0.5 mg l–1) and ascorbic acid (100 mg l–1). Rooting of in vitro produced shoots was readily achieved with indole-3-acetic acid alone (1.0 mg l–1) in MS. The plantlets thus obtained were successfully transferred to pots in large numbers which grew normally.Abbreviations BAP 6-benzylamino purine - 2,4-D 2,4-dichlorophenoxyacetic acid - GA3 gibberellic acid - IAA indole-3-acetic acid - IBA indole-3-butyric acid - 2ip 2-isopentenyladenine - Kn kinetin - MS Murashige & Skoog media - NAA -naphthalene acetic acid  相似文献   

14.
Loblolly pine (Pinus taeda L.) somatic embryogenesis initiation was improved by supplementing the initiation medium with the pH buffer agent 2(n-morpholino)ethanesulphonic acid (MES) at 250 mg l–1, folic acid at 0.5 mg l1, and biotin at 0.05 mg l–1. MES and vitamins increased the percentage of explants with extruded tissue that continued the initiation process to form embryogenic tissue. The increase in initiation was about 12%. Initiation of 12 open-pollinated families averaged 38.5%, which is 16% higher than initiation on medium without these additives. When tested with 18 control-pollinated families, initiation averaged 26.3%. Basal medium contained a combination of modified 1/2 P6 salts, activated carbon (AC) at 50 mg –1, Cu and Zn adjusted to compensate for adsorption by AC, 1.5% maltose, 2% myo-inositol, 500 mg l–1 casamino acids, 450 mg l–1 glutamine, 2 mg l–1 NAA, 0.63 mg l–1 BAP, 0.61 mg l–1 kinetin, 3.4 mg l–1 silver nitrate, 10 M 8-Br-cGMP, 0.1 M brassinolide, and 2 g l–1 Gelrite. Early-stage embryo growth and initiation in Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) were also improved in the presence of these additives.  相似文献   

15.
The contribution of potential export of materials from bottom sedimentsand salt marshes into the water column of a shallow estuarine system of Ria deAveiro to the observed high bacterial productivity in the mid section of thisestuary was evaluated. Vertical profiles of physical, chemical and bacterialvariables were studied in the marine and brackish water zones, and oftransversal profiles in the brackish zone only. Although the concentrations ofseston (17–241 mg l–1), particulate organiccarbon (3–15.5 mg l–1) and chlorophyll(1.2–7.0 g l–1) varied widely, thevertical and transversal profiles were without much variation. Total bacterialnumber (0.2–8.5 × 109 cellsl–1) and the number of particle-attached bacteria(0.02–2.50 × 109 cellsl–1)along vertical and transversal profiles did not differ much, but the rate ofbacterial production (0.05–14.2 g C l–1h–1) and dissolved organic carbon concentration(6.0–69.2 mg l–1) were frequently highernear the salt marsh margin at the brackish water transect. The increase inproductivity could not be associated with runoff of particulate matter butcoincided with the inputs of dissolved organic carbon. The results of verticaland transversal profiles point to a minor role of particulate matter additionsfrom the salt marsh area or from bed sediments.  相似文献   

16.
Plant regeneration from callus cultures of Piper longum was achieved through organogenesis. In vitro grown shoots were used as explants for callus induction. Competent callus was initiated around the nodal ring of tissue using Murashige and Skoog medium supplemented with 1.0 mg.l–1- naphthaleneacetic acid and 0.2 mg.l–1 N6-benzyladenine. Optimum growth regulator concentrations for shoot induction and shoot elongation were found to be 0.5 mg.l–1 indole-3-acetic acid with 1.5 mg.l–1 benzyladenine, and 0.1 mg.l–1 indole-3-acetic acid with 0.2 mg.l–1 benzyladenine, respectively. Elongated shoots were rooted on half-strength Murashige and Skoog medium having 0.1 mg.l–1 indole3-acetic acid. The rooted plants were successfully established in soil.Abbreviations BA, N6 Benzyladenine - 2, 4-D 2, 4- dichlorophenoxyacetic acid - IAA Indole-3-acetic acid - 2iP 2-isopentenyladenine - Kn Kinetin - MS Murashige and Skoog (1962) - NAA -Naphthaleneacetic acid  相似文献   

17.
Photoautotrophic micropropagation of Russet Burbank Potato   总被引:2,自引:0,他引:2  
The photoautotrophic micropropagation of potato cv. Russet Burbank was investigated. Single node microcuttings were grown for four weeks on Murashige and Skoog (MS) medium with or without sucrose (30 g l–1) in the growth room at 21/19 °C day/night temperature, with 16-h photoperiod at 150 mol m–2 s–1, with or without supplemental CO2 at 1500 l l–1. A 20% increase in the number of nodes per stem (from 7.5 to 9.4) and a 50% increase in stem dry weight were observed in cultures grown on media with sucrose and in CO2 enriched atmosphere comparing to the conventionally micropropagated cultures or the cultures grown photoautotrophically on media without sucrose but in air supplemented with 1500 l l–1CO2. Stems of these cultures (from media with sucrose in CO2 enriched air) almost doubled in length the stems of cultures from the other two treatments. No significant differences were observed between Control (MS medium supplemented with sucrose, 30 g l–1) and photoautotrophic cultures coming from MS medium with no sucrose grown under 1500 l l–1 of CO2. Photoautotrophic cultures produced stems averaging 43.3 mm, with 7 nodes and weighing 9.2 mg (dry weight), similar to conventionally grown in vitro cultures (47.9 mm with 7.5 nodes, 9.7 mg dry weight). Growers may consider photoautotrophic culturing of potato in areas where the high sterility levels are difficult to maintain. Supplementing air in the growth room with 1500 l l–1 of CO2 could be beneficial for potato plantlet production even on media containing sucrose since it significantly improved quality, size and biomass of produced plantlets, speeding up the multiplication.  相似文献   

18.
Mg2+, Ca2+, Mn2+, Zn2+, and Cu content of neurons from chick embryo cortex cultivated in chemically defined serum free growth medium was determined by energy dispersive X-ray fluorescence and atomic absorption spectroscopy. The intracellular volume of cultured neurons was determined to be 2.73 l/mg. Intracellular Mn2+, Fe2+, Zn2+, and Cu2+ in the cultivated neurons were 100–200 times the concentrations in the growth medium: Mg2+ and Ca2+ were 0.9 and 1.7 mM respectively, around 20 fold higher than in growth medium. Mg2+, Fe2+, Cu2+ and Zn2+ concentrations in neurons were in the range of ca. 300–600 M, approximately 2–3 times the values previously reported in glial cells; Ca2+ and Mn2+ content of the neurons were higher by 5 and 10 fold respectively compared to glial cells. In neurons, the subcellular distribution of Fe2+, Cu2+, and Mn2+ follows the rank order: cytosol>microsomes>mitochondria; for Zn2+ the distribution differs as following: cytosol >mitochondria>microsomes. Determination of the superoxide dismutase activities in the cultivated neurons indicated that the Mn2+ linked activity predominates whereas, the Cu-Zn dependent enzyme is dominant in glial cells. Enrichment of the culture medium with Mn2+ to 2.5 M enhanced the Mn-SOD by approximately 33% but Cu2+–Zn2+ enzyme activity was not modified. The high Mn2+ content, the capacity to accumulate Mn2+, and the predominancy of the Mn–SOD form observed in neurons is in accord with a fundamental functional role for this metal ion in this type of brain cells.  相似文献   

19.
The order of responses of cell systems of organs and the changes in the content of some proteins in mouse and dog blood in response to addition of natural (-tocopherol) and synthetic (ionol) antioxidants was studied at the whole-body level using ERP spectroscopy, radioisotope analysis, and chemiluminescence technique. Responses were evaluated by the temporary and concentration-dependent changes in the activity of ribonucleotide reductase and the rate of protein and DNA synthesis in organs of the mouse, as well as by the changes in the pools of Fe3+-transferrin and Cu2+-ceruloplasmin in blood and the antiradical activity of blood plasma of the dog and mouse. During the first 24 h of exposure to -tocopherol, the activity ribonucleotide reductase in the bone marrow rapidly increased, whereas the activity of this enzyme and the rate of DNA synthesis in the thymus and spleen were suppressed by 30–50% compared to the control. The changes in these parameters had a phase mode with maxima on days 2–3 and 6–8. The stimulatory effect of the antioxidant on the processes of synthesis was concentration-dependent. We found that the optimal stimulation of the synthesis of deoxyribonucleotides, DNA, and protein was achieved by single administration of -tocopherol at a dose of 20 mg per dog with an average weight of 15 kg and 17 mg/kg in the case of mice. Single or repeated administration of higher doses of -tocopherol was either ineffective or even suppressed the synthesis of DNA and deoxyribonucleotides. Ionol administered at a dose of 60 mg/kg increased DNA and protein synthesis in mouse organs 2–4 and 1.2–1.5 times, respectively, compared to the control. It was also shown that single and repeated administration of -tocopherol to dogs increased the pool of Fe3+-transferrin and Cu2+-ceruloplasmin in blood 2–3 times and by 20–30%, respectively, compared to the control. It is suggested to use changes in Fe3+-transferrin pool in peripheral blood for evaluation of the stimulatory effect of antioxidants on the synthesis of macromolecules in organs and for the determination of dependence of this effect on the concentration of antioxidants.  相似文献   

20.
Plant cell cultures of Peganum harmala converted geranyl acetate to geraniol. Although the reaction started immediately after feeding, there was disappearance of both product and substrate. Geranyl acetate at 100 mg l–1 when fed to 100 ml Peganum harmala suspensions (16% packed cell volume) was completely used within 24 h without accumulation of any product. Similarly, linalyl acetate and its biotransformation products, linalool and -terpineol, disappeared. Controlled-release polymer discs made from poly-2-hydroxyethyl methacrylate and containing concentrations of geranyl acetate or linalyl acetate produced greatly extended concentrations of these substrates and their biotransformation products (from about 1 day to over 12 days). The concentrations of substrates remained at around 5 mg l–1throughout the experiments, while the concentrations of biotransformation products increased from 10 mg l–1to 55.5 mg l–1 for geraniol, from 5 mg l–1 to 14 mg l–1 for linalool, and 5 mg l–1 to 12 mg l–1 for -terpineol compared to the control value. Also low concentrations (30–200 g/disc) of product were taken up by the polymer over 10 days.  相似文献   

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