共查询到20条相似文献,搜索用时 31 毫秒
1.
Leandro Kanamaru Franco de Lima Elisa Helena Giglio Ponsano Marcos Franke Pinto 《World journal of microbiology & biotechnology》2011,27(11):2553-2558
One application of biotechnology that contributes to sustainable development is the utilization of industrial byproducts as
substrates for the production of substances of interest by microorganism. In this work, liquid effluent from tilapia fish
processing was used as a substrate for the growth of Rubrivivax gelatinosus with the aim of studying the bacterial photo heterotrophic metabolism. Cultivation conditions included 32 ± 2°C, 1,400 ± 200
lux and 7 days. In the initial days, the best cell mass production (0.273 g l−1 with 72 h), specific growth rate (0.188 h−1 with 48 h) and chemical oxygen demand (COD) decrease (43% with 72 h) were reached. Typical bacterial oxycarotenoids were
identified after 3 days of cultivation, averaging 3.03 mg g−1 biomass. Bacterial growth in the effluent during the period of study resulted in pH increase to 7.9, total nitrogen, oils
and greases and COD decreases of 22.46, 47.71 and 52%, respectively, and dry cell mass production of 0.18 g l−1. The bacterial growth in the wastewater provided biomass and oxycarotenoids and the removal of pollutant load. 相似文献
2.
Decolorization of Acid red 151 by Aspergillus niger SA1 under different physicochemical conditions 总被引:1,自引:0,他引:1
Naeem Ali Ikramullah Ghosia Lutfullah Abdul Hameed Safia Ahmed 《World journal of microbiology & biotechnology》2008,24(7):1099-1105
The fungal strain A. niger SA1 isolated from textile wastewater pond proved to be an important source of remediation (decolorization/degradation) for
textile dye, AR 151 (Reactive diazo dye) under different physicochemical conditions. Decolorization assays of AR 151 were
carried out in Simulated textile effluent under shake flask condition for 8 days. Decolorization (at 20 mg l−1 of dye) and related biomass production overall decreased with increase in pH from 5 to 9, at 30°C. It was maximum (95.71%)
at pH 5 with highest amount of three residual products (36.91 (α-naphthol = 5.72) (sulfanilic acid = 24.81) (aniline = 6.38))
besides 2.05 mg ml−1 of biomass production at an optimum concentration 6 and 0.1 mg l−1 of glucose and urea respectively. The formation of the three products followed a quite different pattern at different pH
values, however, it was considerably low (Total = 2.81 mg l−1) compared to the amount of decolorization (67.26%) at pH 8. Decolorization (95–97%) was most favored under mesophilic temperature
(25–45°C). It increased i.e., 90–98% with subsequent increase in dye from 10 to 100 mg l−1, kept ≥50% below 400 mg l−1 and drastically declined to 17% at 500 mg l−1 of dye. Apparently, decolorization is found to be associated with fungal growth and hyphal uptake mechanism (Biosorption/Bioadsorption),
however, mineralization of AR 151 and related products under different operational conditions also suggested a metabolically
mediated decolorization/degradation. 相似文献
3.
Reverse process of the coprecipitation of dissolved organic matter with Fe(III) precipitates in a lake is reported. Water
containing a slight amount of dissolved oxygen from the hypolimnion of Lake Onogawa was sealed in glass bottles, and some
changes in the constituents with time were followed. The water sample contained 0.1 mg l−1 dissolved oxygen at the beginning of the experiment, which decreased to 0.0 mg l−1 within 24 h. In response to the depletion of dissolved oxygen, there were increases in dissolved Fe from 8.4 to 11.4 mg l−1 and dissolved organic carbon (DOC) from 5.1 to 6.9 mg l−1 after 72 h. At the beginning of the experiment, more than 2 mg l−1 of insoluble Fe, which was thought to be Fe(III) precipitates, existed in the water samples. When the water samples became
anoxic, the preexisted Fe(III) must have been reduced to soluble Fe(II) over time, resulting in the increase of dissolved
Fe. Simultaneous with Fe(III) reduction, coprecipitated DOC with Fe(III) must have been released. The reverse process of the
coprecipitation of dissolved organic matter with Fe(III) precipitates found in the present study strongly supports in situ
coprecipitation of dissolved organic matter with Fe(III) precipitates.
Contribution No. 27 from the Urabandai Limnological Station, Yamagata University. 相似文献
4.
Herrera-Valencia VA Contreras-Pool PY López-Adrián SJ Peraza-Echeverría S Barahona-Pérez LF 《Current microbiology》2011,63(2):151-157
The aim of this study was to investigate the potential of the green microalga Chlorella saccharophila as a source of oil for biodiesel production. We evaluated for the first time, the effect of salinity and/or nitrogen depletion
(ND) on cell growth, lipid accumulation and lipid profile in this microalga. The fatty acid methyl esters (FAME) identified
for C. saccharophila in this study consisted of C-16:0, C-18:0, C-18:1 cis, and C-18:1 trans. Among these, C-18:1 (indicator of biodiesel quality)
was the main FAME found, representing approximately 76 and 80% of total FAME under normal and ND growing conditions, respectively.
Under a normal growing condition this microalga showed 154.63 mg l−1 d−1, 63.33 mg l−1 d−1, and 103.73 mg l−1 of biomass productivity, lipid productivity, and FAME yield, respectively. The higher biomass productivity (159.58 mg l−1 d−1), lipid productivity (99.33 mg l−1 d−1), and FAME yield (315.53 mg l−1) were obtained under the ND treatment. In comparison to other related studies, our results suggest that C. saccharophila can be considered as a suitable source of oil for biodiesel production. 相似文献
5.
Toxic at low concentrations, phenol is one of the most common organic pollutants in air and water. In this work, phenol biodegradation
was studied in extreme conditions (80°C, pH = 3.2) in a 2.7 l bioreactor with the thermoacidophilic archaeon Sulfolobus solfataricus 98/2. The strain was first acclimatized to phenol on a mixture of glucose (2000 mg l−1) and phenol (94 mg l−1) at a constant dissolved oxygen concentration of 1.5 mg l−1. After a short lag-phase, only glucose was consumed. Phenol degradation then began while glucose was still present in the
reactor. When glucose was exhausted, phenol was used for respiration and then for biomass build-up. After several batch runs
(phenol < 365 mg l−1), specific growth rate (μX) was 0.034 ± 0.001 h−1, specific phenol degradation rate (qP) was 57.5 ± 2 mg g−1 h−1, biomass yield (YX/P) was 52.2 ± 1.1 g mol−1, and oxygen yield factor
( \textY\textX/\textO 2 ) \left( {{\text{Y}}_{{{\text{X}}/{\text{O}}_{ 2} }} } \right) was 9.2 ± 0.2 g mol−1. A carbon recovery close to 100% suggested that phenol was exclusively transformed into biomass (35%) and CO2 (65%). Molar phenol oxidation constant
( \textY\textO 2 /\textP ) \left( {{\text{Y}}_{{{\text{O}}_{ 2} /{\text{P}}}} } \right) was calculated from stoichiometry of phenol oxidation and introducing experimental biomass and CO2 conversion yields on phenol, leading to values varying between 4.78 and 5.22 mol mol−1. Respiratory quotient was about 0.84 mol mol−1, very close to theoretical value (0.87 mol mol−1). Carbon dioxide production, oxygen demand and redox potential, monitored on-line, were good indicators of growth, substrate
consumption and exhaustion, and can therefore be usefully employed for industrial phenol bioremediation in extreme environments. 相似文献
6.
A sequencing batch reactor system for high-level biological nitrogen and phosphorus removal from abattoir wastewater 总被引:2,自引:0,他引:2
A sequencing batch reactor (SBR) system is demonstrated to biologically remove nitrogen, phosphorus and chemical oxygen demand
(COD) to very low levels from abattoir wastewater. Each 6 h cycle contained three anoxic/anaerobic and aerobic sub-cycles
with wastewater fed at the beginning of each anoxic/anaerobic period. The step-feed strategy was applied to avoid high-level
build-up of nitrate or nitrite during nitrification, and therefore to facilitate the creation of anaerobic conditions required
for biological phosphorus removal. A high degree removal of total phosphorus (>98%), total nitrogen (>97%) and total COD (>95%)
was consistently and reliably achieved after a 3-month start-up period. The concentrations of total phosphate and inorganic
nitrogen in the effluent were consistently lower than 0.2 mg P l−1 and 8 mg N l−1, respectively. Fluorescence in situ hybridization revealed that the sludge was enriched in Accumulibacter spp. (20–40%), a known polyphosphate accumulating organism, whereas the known glycogen accumulating organisms were almost
absent. The SBR received two streams of abattoir wastewater, namely the effluent from a full-scale anaerobic pond (75%) and
the effluent from a lab-scale high-rate pre-fermentor (25%), both receiving raw abattoir wastewater as feed. The pond effluent
contained approximately 250 mg N l−1 total nitrogen and 40 mg P l−1 of total phosphorus, but relatively low levels of soluble COD (around 500 mg l−1). The high-rate lab-scale pre-fermentor, operated at 37°C and with a sludge retention time of 1 day, proved to be a cheap
and effective method for providing supplementary volatile fatty acids allowing for high-degree of biological nutrient removal
from abattoir wastewater. 相似文献
7.
Morinda citrifolia adventitious roots were cultured in shake flasks using Murashige and Skoog medium with different types and concentrations
of auxin and cytokinin. Root (fresh weight and dry weight) accumulation was enhanced at 5 mg l−1 indole butyric acid (IBA) and at 7 and 9 mg l−1 naphthalene acetic acid (NAA). On the other hand, 9 mg l−1 NAA decreased the anthraquinone, phenolic and flavonoid contents more severely than 9 mg l−1 IBA. When adventitious roots were treated with kinetin (0.1, 0.3 and 0.5 mg l−1) and thidiazuron (TDZ; 0.1, 0.3 and 0.5 mg l−1) in combination with 5 mg l−1 IBA, fresh weight and dry weight decreased but secondary metabolite content increased. The secondary metabolite content (including
1,1-diphenyl-2-picrylhydrazyl activity) increased more in TDZ-treated than in kinetin-treated roots. Antioxidative enzymes
such as catalase (CAT) and guaiacol peroxidase (G-POD), which play important roles in plant defense, also increased. A strong
decrease in ascorbate peroxidase activity resulted in a high accumulation of hydrogen peroxide. This indicates that adventitious
roots can grow under stress conditions with induced CAT and G-POD activities and higher accumulations of secondary metabolites.
These results suggest that 5 mg l−1 IBA supplementation is useful for growth and secondary metabolite production in adventitious roots of M. citrifolia. 相似文献
8.
Mashitha Pise Jaishree Rudra Sunita Bundale Deovrat Begde Nandita Nashikkar Avinash Upadhyay 《In vitro cellular & developmental biology. Plant》2012,48(1):85-91
Asparagus racemosus is an important monocot medicinal plant that is in great demand for its steroidal saponins called shatavarins. This study
was initiated to optimize the conditions for production of shatavarins in cell cultures of A. racemosus in a modified Murashige and Skoog (MS) medium supplemented with six different combinations of growth regulators. Biomass
accumulation was correlated with saponin production over a 30-d culture cycle. Biomass and saponin accumulation patterns were
dependent on combinations of growth regulators and the pH of the medium. Maximum levels of saponin and biomass accumulation
were recorded on day 25 of the culture cycle within a pH range of 3.4 to 5.6. Total saponin produced by the in vitro cultures was 20-fold higher than amounts produced by cultivated plants. Saponin accumulation was not a biomass-associated
phenomenon; cultures which showed the highest biomass accumulation were not the highest saponin accumulators. Maximum biomass
(28.30 ± 0.29 g l−1) and maximum levels of shatavarin IV(11.48 ± 0.61 mg g−1) accumulation was found using a medium containing 2.0 mg l−1 2,4-D, 2 g l−1 casein hydrolysate and 0.005% pectinase. The highest levels of sarsapogenin, secreted and intracellular (4.02 ± 0.09 mg g−1), accumulated using a medium containing 1.0 mg l−1 NAA, 1.0 mg l−1 2,4-D, 0.5 mg l−1 BAP, 2 g l−1 casein hydrolysate and 0.005% pectinase, after 25 d. Shatavarins were secreted into the medium and can be isolated easily
for further purification. 相似文献
9.
The denitrification performance of a lab-scale anoxic rotating biological contactor (RBC) using landfill leachate with high
nitrate concentration was evaluated. Under a carbon to nitrogen ratio (C/N) of 2, the reactor achieved N-NO3
− removal efficiencies above 95% for concentrations up to 100 mg N-NO3
− l−1. The highest observed denitrification rate was 55 mg N-NO3
− l−1 h−1 (15 g N-NO3
− m−2 d−1) at a nitrate concentration of 560 mg N-NO3
− l−1. Although the reactor has revealed a very good performance in terms of denitrification, effluent chemical oxygen demand (COD)
concentrations were still high for direct discharge. The results obtained in a subsequent experiment at constant nitrate concentration
(220 mg N-NO3
− l−1) and lower C/N ratios (1.2 and 1.5) evidenced that the organic matter present in the leachate was non-biodegradable. A phosphorus
concentration of 10 mg P-PO4
3− l−1 promoted autotrophic denitrification, revealing the importance of phosphorus concentration on biological denitrification
processes. 相似文献
10.
Nisar Ahmad Hina Fazal Bilal Haider Abbasi Muhammad Rashid Tariq Mahmood Nighat Fatima 《Plant Cell, Tissue and Organ Culture》2010,102(1):129-134
The organogenic potential and antioxidant potential (1, 1-diphenyl-2-picrylhydrazyl-scavenging activity) of the medicinal
plant Piper nigrum L. (black pepper) were investigated. Callus induction and shoot regeneration were induced from leaf explants of potted plants
cultured on MS medium supplemented with different plant growth regulators. The best callogenic response was observed on explants
cultured for 30 days on MS medium supplemented with either 0.5 or 1.5 mg l−1 6-benzyladenine (BA) + 1.0 mg l−1 α-naphthaleneacetic acid. Subsequent transfer of the callogenic explants onto MS medium supplemented with 1.5 mg l−1 BA + 1.0 mg l−1 gibberellic acid (GA3) achieved 85% shoot organogenesis after 30 days of culture. The maximum number (7.2) of shoots/explant was recorded for explants
cultured in MS medium supplemented with 1.0 mg l−1 BA. Following the transfer of shoots to an elongation medium, the longest shoots (5.4 cm) were observed on MS medium supplemented
with 1.0 mg l−1 BA + 1.0 mg l−1 GA3. The elongated shoots were rooted on MS medium supplemented with different concentrations of indole butyric acid. An assay
of the antioxidant potential of the in vitro-grown tissues revealed that the antioxidant activity of the regenerated shoots
was significantly higher than that of callus and the regenerated plantlets. 相似文献
11.
Morteza Shabannejad Mamaghani Mohammad Hassan Assareh Mansoor Omidi Mohammad Matinizadeh Abbas Ghamari-Zare Shokofeh Shahrzad Massih Forootan 《Plant Growth Regulation》2009,59(3):199-205
The green twigs of 1-year-old Eucalyptus microtheca F. Muell seedlings were cultured on modified MS medium, supplemented with α-naphthalene acetic acid (NAA) and kinetin (Kin)
hormones at 12 different concentrations. After 4 weeks, the combination of 1 mg l−1 NAA + 1 mg l−1 Kin induced the highest number of axillary shoots. Meanwhile, embryogenic calli were observed in media containing 4 mg l−1 NAA + 0.5 mg l−1 Kin, without any regeneration. The hormone treatments were followed by subculturing the twigs in different levels of thidiazuron
(TDZ). The combination of 1 mg l−1 NAA + 1 mg l−1 Kin together with 0.01 mg l−1 TDZ resulted in an increase of direct shoot, while higher amounts of TDZ led to adventitious shoot induction. Somatic embryogenesis
was observed in the treatment containing 0.01 mg l−1 TDZ + 4 mg l−1 NAA + 0.5 mg l−1Kin. The peroxidase (POD) band patterns in regenerated plantlets were investigated in order to determine the effect of different
levels of TDZ on loci synthesis. A dimer locus, a tetramer locus and two epigenetic bands (a new band for NAA + Kin and the
other for TDZ) were observed in the POD profiles. In case of low (0.01 mg l−1 and 0.1 mg l−1) levels of TDZ, one heterozygote allele was disappeared from dimer locus, while at higher TDZ levels, the dimer locus lost
its stability and tetramer locus showed a high activity. Thus, POD allele patterns seems to be a feasible marker for different
types of regeneration. 相似文献
12.
The activated sludge process (ASP) has high operational costs due to the need for aeration at dissolved O2 (DO) levels of ≥2 mg l−1 and high capital costs to construct large reactors due to a low organic loading [typically 1 kg chemical oxygen demand (COD) m−3 day−1]. A novel method for improving the energy use and treatment efficiency of the ASP via limited oxygenation (0.4 mg DO l−1) and high organic loading (6.2 kg COD m−3 day−1) is proposed based on a laboratory-scale ASP for ammonia-rich industrial wastewaters. The sludge blanket phenomenon and granulation
occurred simultaneously in the upflow microaerobic reactor. 相似文献
13.
14.
Behzad Ahmadi Khoshnood Alizadeh Jaime A. Teixeira da Silva 《Plant Cell, Tissue and Organ Culture》2012,109(3):525-533
The effects of three periods of incubation (10, 20 and 30 min) at different levels of bleomycin (0, 0.1, 0.2, 0.3, 0.4 and
0.5 μg ml−1), as well as three periods of exposure (12, 24 and 48 h) to different levels of the anti-auxin p-chlorophenoxyisobutyric acid (PCIB), including 1, 2, 3, 4 and 5 mg l−1, on microspore embryogenesis of rapeseed cv. ‘Amica’ were investigated. Microspore embryogenesis was significantly enhanced
following 20 min treatment with 0.2 μg ml−1 bleomycin compared with untreated cultures. Highest embryo yield (163 embryos Petri dish−1) was observed with 24 h treatment of 4 mg l−1 PCIB. The highest percentage of secondary embryogenesis was observed on B5 medium containing 0.15 mg l−1 of gibberellic acid (GA3) and 0.2 mg l−1 6-benzyladenine (BA) in 4–6 mm microspore-derived embryos (MDEs). Most callus formed on B5 medium containing 0.15 mg l−1 GA3, 0.1 mg l−1 BA and 0.1 mg l−1 indole-3-acetic acid (IAA) when 4–6 mm embryos were used. Regeneration was highest on B5 medium containing 0.05 mg l−1 GA3 or 0.1 mg l−1 BA and 0.2 mg l−1 IAA with 2–4 mm embryos. Microspore embryogenesis and plant regeneration could be improved by both bleomycin and PCIB when
the appropriate MDE length and phytohormone level were selected. 相似文献
15.
The green microalga Chlorella zofingiensis can produce the ketocarotenoid astaxanthin under heterotrophic culture conditions. Here we report the growth-associated biosynthesis
of astaxanthin in this biotechnologically important alga. With glucose as sole carbon and energy source, C. zofinginesis grew fast in the dark with rapid exhaustion of nitrogen and carbon sources from media, leading to a high specific growth
rate (0.034 h−1). Cultures started at a cell concentration of about 3.4 × 109 cells l−1 reached, after 6 days, standing biomass values of 1.6 × 1011 cells or 8.5 g dry weight l−1. Surprisingly, the biosynthesis of astaxanthin was found to start at early exponential phase, independent of cessation of
cell division. A general trend was observed that the culture conditions benefiting cell growth also benefited astaxanthin
accumulation, indicating that astaxanthin was a growth-associated product in this alga. The maximum cell dry biomass and astaxanthin
yield were 11.75 g l−1 and 11.14 mg l−1 (about 1 mg g−1), simultaneously obtained in the fed-batch culture with a combined glucose–nitrate mixture addition, which were the highest
ever reported in dark-heterotrophic algal cultures. The possible reasons why dark-heterotrophic C. zofingiensis could produce astaxanthin during the course of cell growth were discussed. 相似文献
16.
Kusampudi Shilpa Chinnasamy Selvakkumar Arun Kumar Senthil Baddireddi Subhadra Lakshmi 《Plant Cell, Tissue and Organ Culture》2010,101(1):105-109
Young leaf explants of Ocimum sanctum L. incubated on solidified Murashige and Skoog (MS) medium supplemented with 2 mg l−1 1-naphthaleneacetic acid (NAA) and 0.2 mg l−1 kinetin (Kn) developed rhizogenic callus. When these were subcultured onto MS medium supplemented with 1.5 mg l−1 2, 4-dichlorophenoxyacetic acid (2, 4-D) and 0.5 mg l−1 NAA, friable rhizogenic callus was observed. Upon transfer of this friable callus onto liquid MS medium containing 4 mg l−1 NAA and 1.3 mg l−1 6-benzyladnine (BA) under continuous agitation at 90 rpm and 16 h photoperiod, roots with an optimum dry weight of 1,460 mg l−1 were obtained. An ethyl acetate extract of these roots exhibited 1, 1–diphenyl-2-picrylhydrazyl (DPPH) radical scavenging
activity. 相似文献
17.
Quinn P. Fitzgibbon Roger S. Seymour Jeffery Buchanan Richard Musgrove John Carragher 《Environmental Biology of Fishes》2010,89(1):59-69
Of the few measurements of the behavioural and physiological responses of tuna to hypoxia, most are restricted to shallow
diving tropical species. Furthermore, when wild tuna experience low dissolved oxygen, they are likely to have an increased
oxygen demand associated with the metabolic cost of food digestion and assimilation (specific dynamic action). However the
response of postprandial tuna to hypoxia has never been examined. This study focuses on the metabolic and behavioural responses
of both fasted and postprandial southern bluefin tuna (Thunnus maccoyii) to low dissolved oxygen. Fasted T. maccoyii were exposed to dissolved oxygen levels of 4.44, 3.23, 2.49 and 1.57 mg·l−1 for 20–21 h. In moderate hypoxia (4.44 and 3.23 mg·l−1), swimming speed was enhanced (1.5 and 1.3 times normoxic speed, respectively) presumably to increase ventilation volume.
Routine metabolic rate (R
r
) was similarly elevated (1.3 and 1.2 times normoxic R
r
, respectively), most likely due to increased metabolic demand of faster swimming. At 2.49 mg·l−1, swimming speed increased to over double the normoxic speed, possibly as an escape response. At 1.57 mg·l−1, both swimming speed and R
r
were reduced (0.8 and 0.9 times normoxic level, respectively), and tuna failed to survive the entire 20 h exposure period.
This reveals that the critical oxygen level of T. maccoyii is between 1.57 and 2.49 mg·l−1, demonstrating that they are remarkably well adapted to low dissolved oxygen. Feeding did not greatly influence their hypoxia
tolerance with tuna surviving exposure to dissolved oxygen levels of 2.96 and 1.81 mg·l−1 for 21 h, after ingesting a ration of 6.7% body weight of sardines (Sardinops sagax). In a subsequent experiment to determine the effects of hypoxia on digestion rate, T. maccoyii were fed to satiation and exposed to a dissolved oxygen level of 2.84 mg·l−1 for 6.5–8 h. There was no significant difference in swimming speed, R
r
and gastric evacuation rates of tuna in hypoxia compared to those in normoxia. This demonstrates that in moderate to severe
hypoxia, T. maccoyii are still capable of aerobically supporting maintenance metabolism, routine swimming and specific dynamic action. It is hypothesized
that adaptations which support the large metabolic scope of tuna are also likely to be beneficial for oxygen extraction and
delivery in conditions of hypoxia. 相似文献
18.
Smita Srivastava Ashok Kumar Srivastava 《In vitro cellular & developmental biology. Plant》2012,48(1):73-84
Azadirachtin, a well-known biopesticide, is a secondary metabolite extracted from the seeds of Azadirachta indica. In the present study, azadirachtin was produced in hairy roots of A. indica, generated by Agrobacterium rhizogenes-mediated transformation of leaf explants. Liquid cultures of A. indica hairy roots were developed with a liquid-to-flask volume ratio of 0.15. The kinetics of growth and azadirachtin production
were established in a basal plant growth medium containing MS medium major and minor salts, Gamborg’s medium vitamins, and
30 g l−1 sucrose. The highest azadirachtin accumulation in the hairy roots (up to 3.3 mg g−1) and azadirachtin production (∼44 mg l−1) was obtained on Day 25 of the growth cycle, with a biomass production of 13.3 g l−1 dry weight. To enhance the production of azadirachtin, a Plackett–Burman experimental design protocol was used to identify
key medium nutrients and concentrations to support high root biomass production and azadirachtin accumulation in hairy roots.
The optimal nutrients and concentrations were as follows: 40 g l−1 sucrose, 0.19 g l−1 potassium dihydrogen phosphate, 3.1 g l−1 potassium nitrate, and 0.41 g l−1 magnesium sulfate. Concentrations were determined by a central composite design protocol and verified in shake-flask cultivation.
The optimized medium composition yielded a root biomass production of 14.2 g l−1 and azadirachtin accumulation of 5.2 mg g−1, which was equivalent to an overall azadirachtin production of 73.84 mg l−1, 68% more than that obtained under non-optimized conditions. 相似文献
19.
N. Irvani M. Solouki M. Omidi A. R. Zare S. Shahnazi 《Plant Cell, Tissue and Organ Culture》2010,100(3):293-299
Dorema ammoniacum D. Don. (Apiaceae), a native medicinal plant in Iran, is classified as a vulnerable species. Root, hypocotyl, and cotyledon
segments were cultured on Murashige and Skoog (MS) (1962) medium supplemented with either 2,4-dichlorophenyoxyacetic acid
(2,4-D) or naphathalene acetic acid (NAA), at 0–2 mg l−1, alone or in combination with either benzyladenine (BA) or kinetin (KN), at 0–2 mg l−1 for callus induction. The best response (100%) was observed from root segments on MS medium containing 1 mg l−1 NAA and 2 mg l−1 BA. The calli derived from various explants were subcultured on MS medium supplemented with BA (1–4 mg l−1) alone or in combination with NAA or indole-3-butyric acid (IBA), at 0.2 or 0.5 mg l−1 for shoot induction. Calli derived from hypocotyl segments showed significantly higher frequency of plantlet regeneration
and number of plantlets than the calli derived from root and cotyledon segments. Therefore, MS medium supplemented with 2 mg l−1 BA and 0.2 mg l−1 IBA produced the highest frequency of shoot regeneration (87.3%) in hypocotyl-derived callus. The optimal medium for rooting
contained 2.5 mg l−1 IBA on which 87.03% of the regenerated shoots developed roots with an average number of 5.2 roots per shoots within 30 days.
These plantlets were hardened and transferred to the soil. The described method can be successfully employed for the large-scale
multiplication and conservation of germplasm this plant. 相似文献
20.
Meiru Li Hongqing Li Xiaoying Hu Xiaoping Pan Guojiang Wu 《Plant Cell, Tissue and Organ Culture》2011,106(3):363-371
Saussurea involucrata is a valuable traditional Chinese medicinal herb. This is the first report of a successful genetic transformation protocol
for S. involucrata using Agrobacterium tumefaciens. Leaf explants were incubated with A. tumefaciens strain EHA105 harboring the binary vector pCAMBIA 1301, which contains the hpt gene as a selectable marker for hygromycin resistance and an intron-containing β-glucuronidase gene as a reporter gene. Following
co-cultivation, about 23.7% of the explants produced hygromycin-resistant calli on MS basal medium (Murashige and Skoog in
Physiol Plant 15: 473–497, 1962) supplemented with 1 mg l−1 benzyladenine (BA), 0.1 mg l−1 α-naphthaleneacetic acid (NAA), 0.1 mg l−1 2,4-dichlorophenoxyacetic acid (2,4-D), 20 mg l−1 hygromycin, and 500 mg l−1 cefotaxime. Shoots were regenerated following transfer of the resistant calli to shoot induction medium containing 1.5 mg l−1 BA, 0.1 mg l−1 NAA, 0.25 mg l−1 gibberellic acid (GA3), 20 mg l−1 hygromycin, and 250 mg l−1 cefotaxime, and about 67.5% of the resistant calli differentiated into shoots. Finally, 80% of the hygromycin-resistant shoots
rooted on MS media supplemented with 0.2 mg l−1 NAA, 20 mg l−1 hygromycin, and 250 mg l−1 cefotaxime. The transgenic nature of the transformants was demonstrated by detection of β-glucuronidase activity in the primary
transformants and by Southern blot hybridization analysis. About 16% of the total inoculated leaf explants produced transgenic
plants after approximately 5 months. Using this optimized transformation system, a rice ortholog of the Arabidopsis FLOWERING LOCUS T gene, Hd3a, was transferred into S. involucrata. Introduction of this gene caused an early-flowering phenotype in S. involucrata. 相似文献