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1.
Panaia M. Senaratna T. Bunn E. Dixon K.W. Sivasithamparam K. 《Plant Cell, Tissue and Organ Culture》2000,63(1):23-29
A micropropagation protocol was developed for the conservation of the critically endangered Western Australian shrub,Symonanthus bancroftii. It was necessary to screen antioxidant treatments to prevent the occurrence of lethal browning of explants upon excision.
Potassium citrate and citric acid (0.1% w/v in a 4:1 ratio) prevented oxidative browning and was superior to the untreated
control or other antioxidant treatments tested. Half strength Murashige and Skoog (MS) medium containing 0.5 μM kinetin and
0.25 μM benzyladenine produced three-fold multiplication compared to 1.75×, 1.5×, 1.8× and 1× multiplication for 2.5 μM kinetin
+ 0.25 μM benzyladenine, 0.5 μM kinetin + 5 μM gibberellic acid, 1 μM kinetin + 3 μM gibberellic acid and half strength MS
with no plant growth regulators, over 4 weeks. Root production was achieved with indole-3-butyric acid (IBA) and α-naphthaleneacetic
acid (NAA) at 0.5/0.5 μM (31% rooting) and 1.0/1.0 μM (36% rooting), after four weeks. Paclobutrazol (PBZ) at 0, 3.4 (1 mg
1−1), 10.2 (3 mg 1−1), or 17 μM (5 mg 1−1) improved tolerance to desiccation after transfer ofin vitro rooted shoots to soil. PBZ at 10.2 μM increased survival to 90% compared to 50% for those plantlets not treated with PBZ.
The acclimatisation period from the glasshouse to the shadehouse was 1 week for plantlets treated with PBZ compared to 4 weeks
for plantlets without any PBZ. PBZ at 3.4 μM increased the number of roots per shoot compared to untreated controls.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
2.
Nodular callus was induced at a high frequency on young purple red, 5–15 mm long laminae taken from in vitro grown plants of mangosteen. The optimal medium was composed of Murashige and Skoog (MS) nutrients supplemented with 2.22
μM benzyladenine (BA), 2.25 μM thidiazuron (TDZ), 500 mg l-1 polyvinylpyrrolidone (PVP 360 000) and 3% sucrose. A multiplication rate of two–three was obtained by subculture of the nodular
callus at 3–4-week intervals. Plantlet regeneration from the nodules was achieved by transfer to woody plant medium (WPM)
with 500 mg l-1 PVP, 0.4 μM BA and 3% sucrose and overlaying with half strength liquid MS containing 0.32 μM naphthaleneacetic acid (NAA),
0.13 μM BA and 3% sucrose. Elongated shoots were rooted to 100% when wounded at the base of shoot, dipped in 4.4 mM indolebutyric
acid (IBA) solution in the dark for 15 min and cultured on WPM supplemented with 1.11 μM BA, 0.25% activated charcoal, 34.5
μM phloroglucinol (PG) and 3% sucrose.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
3.
Friable callus cultures were initiated from cotyledons and hypocotyls of Opuntia ficus-indica. Explants from cotyledons produced significantly more callus than those from hypocotyls. Optimum callus growth was observed
on Murashige & Skoog medium supplemented with 0.9 μM 6-furfurylaminopurine, 2.3 μM 2,4-dichlorophenoxyacetic acid, 1.0 μM
4-amino 3,5,6-trichloropicolinic acid, 400 mg l-1 casein hydrolysate and 3% sucrose. The same medium without agar was used for establishing cell suspensions.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
4.
Indole-3-butyric acid at 25 μM with methyl jasmonate (MJ) at 100 μM in Panax ginseng synergistically stimulated both root growth and ginsenoside accumulation compared with 100 μM MJ alone. Productivity of ginsenoside
was 10 mg l−1 d−1 compared to 7.3 mg l−1 d−1 with MJ elicitation alone. 相似文献
5.
A procedure is outlined for the establishment of a proliferating cell suspension culture and subsequent plant regeneration
of the latex-producing plant,Calotropis gigantea (Linn.) R. Br. Friable calluses were obtained by culturing hypocotyl explants on modified Murashige and Skoog medium with
2.69 μM α-naphthaleneacetic acid and 4.44 μM 6-benzyl-aminopurine. Friable calluses were transferred to modified Murashige
and Skoog liquid medium containing 500 mg l−1 casein hydrolysate, 5% (v/v) coconut water and 5% (w/v) sucrose to initiate suspension cultures. Suspensions were subcultured
every 10–12 days and supplemented with 13.56 μM 2,4-dichlorophenoxyacetic acid (2,4-D). After 3–4 subcultures, suspensions
consisted of small, highly cytoplasmic cell clumps and large vacuolate cells. Plating the suspension clumps on medium containing
4.52 μM 2,4-dichlorophenoxyacetic acid and culturing in darkness produced macroscopic calluses, which subsequently produced
a high number of shoots when placed in light and supplemented with 2.22 μM 6-benzyl-aminopurine and 0.45 μM 2,4-dichlorophenoxyacetic
acid. Shoots were rooted using Bonner's solution containing 0.49 μM indole-3-butyric acid, and the plants successfully transferred
to soil.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
6.
A regeneration system was developed for Prunus serotina from a juvenile (F) and two mature genotypes (#3 and #4). Adventitious shoots regenerated from leaves of in vitro cultures
on woody plant medium with thidiazuron (TDZ) and naphthaleneacetic acid (NAA). The best regeneration for genotype F (91.4%)
was observed on medium with 9.08 μM TDZ and 1.07 μM NAA. The highest mean number of shoots (8.2) was obtained on medium containing
9.08 μM TDZ and 0.54 μM NAA. Genotype #3 had the highest regeneration (41.7%) with a mean number of shoots (4.8) on 9.08 μM
TDZ and 1.07 μM NAA, whereas genotype #4 had a 38.8% regeneration with a mean of 3.3 shoots. Genotype #4 had the highest mean
number of shoots (4.8) on 4.54 μM TDZ and 1.07 μM NAA. Silver thiosulphate at 60 or 80 μM increased the percent regeneration
of the mature genotypes #3 (75%) and #4 (58%). Adventious shoots were rooted (70–76%) and rooted plantlets survived after
acclimatization to the greenhouse. The effect of kanamycin concentration on adventitious shoot regeneration was also evaluated. 相似文献
7.
In vitro mother plants initiated from a mature tree of Sorbus aucuparia, produced numerous propagules on a medium containing 2 μM 6-benzylaminopurine (BAP) and 0.2 μM 1-naphthaleneacetic acid (NAA).
These were rooted on a medium containing 0.25 μM NAA and 0.25 μM indole−3-butyric acid. Adventitious shoots were produced
on excised leaves and internodes on media containing 10 μM thidiazuron and 0.3–1.0 μM NAA. They formed by direct regeneration
in the axils of leaflets of intact leaves. They also developed indirectly, from callus that developed on the rachis of intact
leaves, and the cut ends of petioles and internodes. Somatic embryos were produced on cotyledons of zygotic embryos on medium
containing 1 μM BAP, 1 μM kinetin, 0.5 μM NAA, 500 mg l−1 casein hydrolysate and 250 mg l−1 glutamine. On basal medium, 69% developed cotyledons and 20% germinated after pre-treatment at 4 °C on medium containing
30 g l−1 maltose. 相似文献
8.
Factors affecting successful establishment in vitro, rapid proliferation and rooting of apricot cultivar ‘Bebecou’ were studied. Ethanol and NaOCl were applied in several combinations for disinfection; chilling, plant growth regulators BA, IAA and GA3, antibiotics, different culture vessels and systems of subculture were evaluated for the optimization of shoot proliferation and the auxins NAA and IBA were assessed for root induction. The highest number of new microshoots/explant (18.7) was obtained in a culture medium supplemented with 2.2 μM BA+0.57 μM IAA after 300 h of chilling. The effect of GA3 (11.4 μM) on shoot proliferation was positive in combination with 4.4 or 8.9 μM BA. Shoot length and productivity were highest at 2.2 μM BA+11.4 μM GA3+0.57 μM IAA and at 2.2 μM BA+0.57 μM IAA, respectively and decreased as cytokinin concentration increased. The antibiotic ‘Na-cefotaxime’ had a minimal impact on shoot growth when used at the lowest concentration (250 mg l−1). Subculture every 2 weeks in a medium supplemented with 2.2 μM BA and 0.57 μM IAA was more efficient for shoot induction than alternation of 20 days culture in a propagation medium supplemented with 2.2 μM BA and 10 days culture in an elongation medium supplemented with 1.1 μM BA and 5.71 μM IAA. The highest number of roots/shoot (8.1) was recorded at 19.6 μM IBA. 相似文献
9.
Fish kills of milkfish Chanos chanos and tilapia Oreochromis spp. now occur frequently in brackish, marine, and freshwater
farms (ponds, pens, and cages) in the Philippines. Aquafarms with high organic load, limited water exchange and circulation,
no aeration, and high stocking and feeding rates can become oxygen-depleted and allow sulfide from the sediments to appear
in the water column and poison free-swimming fish. The sulfide tolerance of 2–5 g milkfish and 5–8 g O. mossambicus was determined
in 25-liter aquaria with flow-through sea water (100 ml min-1) at 26–30 °C and sulfide stock solutions pumped in at 1ml min-1.
Total sulfide concentrations in the aquaria were measured by the methylene blue method and used in the regression against
the probits of % survival. Four experiments showed that the two species have similar sulfide tolerance. In sea water of pH
8–8.5, about 163 ± 68 μM or 5.2 ± 2.2 mg l-1 total sulfide (mean ± 2 se) or 10 μM or 313 μg l-1 H2S was lethal to 50% of the
fish in 4–8 h, and 61 ± 3 μM total sulfide or 4 μM H2S in 24–96 h (to convert all sulfide concentrations: 1 μM = 32 μg l-1).
Earthen pond bottoms had 0–382 μM total dissolved sulfide (mean ± sd = 54 ± 79 μM, n = 76); a tenth of the samples had >200
μM. The water column may have such sulfide levels under hypoxic or anoxic conditions. To simulate some of the conditions during
fish kills, 5–12 g milkfish were exposed to an abrupt increase in sulfide, alone or in combination with progressive respiratory
hypoxia and decreasing pH. The tests were done in the same flow-through set-up but with sulfide pumped in at 25 ml min-1.
The lethal concentration for 50% of the fish was 197 μM total sulfide or 12 μM H2S at 2 h, but 28–53 μM sulfide allowed fish
to survive 6–10 h. Milkfish in aquaria with no aeration nor flow-through sea water died of respiratory hypoxia in 5–8 h when
oxygen dropped from 6 to 1 mg l-1. Under respiratory hypoxia with 30–115 μM sulfide, the fish died in 2.5–4 h. Tests with
low pH were done by pumping a weak sulfuric acid solution at 25 ml min-1 into aquaria with flow-through sea water such that
the pH dropped from 8 to 4 in 5 h. Under these conditions, milkfish died in 7–9 h when the pH was 3.5. When 30–93 μM sulfide
was pumped in with the acid, the fish died in 2–6 h when the pH was still 4.5–6.3. Thus, sulfide, hypoxia, and low pH are
each toxic to milkfish at particular levels and aggravate each other's toxicity. Aquafarms must be well oxygenated to prevent
sulfide toxicity and fish kills.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
10.
L. Ferraro S. Tanganelli L. Marani C. Bianchi L. Beani A. Siniscalchi 《Neurochemical research》1996,21(5):547-552
The effects of α-glycerylphosphorylcholine (α-GPC) on endogenous cortical GABA release were studied both in vivo and in vitro.
In freely moving rats, equipped with epidural cups, α-GPC (30–300 mg/kg i.p.) increased GABA release. This effect was potentiated
by atropine, both systematically administered (5 mg/kg i.p.) and locally applied (1.4 μM), but not by mecamylamine (4 mg/kg
i.p.). The α-GPC-induced increasein GABA release was abolished in rats pretreated with the α1 receptor antagonist prazosin (14 μg/kg i.p.). In cortical slices α-GPC (0.4 mM) increased the spontaneous GABA efflux. This effectwas abolished by tetrodotoxin (0.5 μM) and prazosin (1 μM), but not by atropine (0.15 μM) ormecamylamine (2.5μM). These results indicate that the facilitatory response by α-GPC on GABArelease does not depend on a direct activation of either muscarinic or nicotinic receptors, but suggest the involvement of the noradrenergic
system. 相似文献
11.
In vitro propagation of northern red oak (Quercus rubra) shoots was successful from cotyledonary node explants excised from 8-wk-old in vitro grown seedlings. Initially, four shoots per explant were obtained on Murashige and Skoog (MS) medium supplemented with 4.4 μM
6-benzylaminopurine (BA), 0.45 μM thidiazuron (TDZ), and 500 mg l−1 casein hydrolysate (CH) with a regeneration frequency of 64.7% after 3 wk. Subculturing explants (after harvesting shoots)
to fresh treatment medium significantly increased shoot bud regeneration (16.6 buds per explant), but the buds failed to develop
into shoots. A higher percentage (73.3%) of the explants regenerated four shoots per explant on woody plant medium (WPM) supplemented
with 4.4 μM BA, 0.29 μM gibberellic acid (GA3), and 500 mg l−1 CH after 3 wk. Explants subcultured to fresh treatment medium after harvesting shoots significantly increased shoot regeneration
(16 shoots per explant). Shoot elongation was achieved (4 cm) when shoots were excised and cultured on WPM supplemented with
0.44 μM BA and 0.29 μM GA3. In vitro regenerated shoots were rooted on WPM supplemented with 4.9 μM indole-3-butyric acid. A higher percentage regeneration response
and shoot numbers per explant were recorded on WPM supplemented with BA and GA3, than on MS medium containing BA and TDZ. Lower concentrations of BA and GA3 were required for shoot elongation and prevention of shoot tip necrosis. Each cotyledonary node yielded approximately 20
shoots within 12 wk. Rooted plantlets were successfully acclimatized. 相似文献
12.
An efficient micropropagation system via direct shoot organogenesis from hypocotyl segments of Embelia ribes Burm F. was developed. A high frequency (84%) of adventitious shoot induction was obtained on Murashige and Skoog (MS) medium
supplemented with additives (283.85 μM ascorbic acid [AA], 118.96 μM citric acid [CA], 142.33 μM cysteine, and 684.22 μM glutamine)
and 1.13 μM of thidiazuron (TDZ) after 4 weeks following culture. Further development of shoot primordia into well-grown shoots
of 4–5 cm in length was achieved by sub-culturing explants along with shoot primordia on MS medium supplemented with 0.44 μM
benzyl adenine (BA) and 0.49 μM indole butyric acid (IBA) for three sub-culture periods with an interval of 15 days between
them. The highest shoot multiplication was obtained when explants were incubated on MS medium supplemented with 2.2 μM BA
and 0.49 μM IBA in 4 weeks. All in vitro developed shoots, 3–4 cm in length, rooted when grown on half-strength MS basal medium
along with 2.47 μM IBA within 4 weeks. Moreover, 100% of shoots developed roots when these were treated with 4.93 μM IBA for
20 min and then transferred to pots containing soilrite mix and grown in the greenhouse. In vitro and ex vitro rooted plants
showed a survival of 85 and 95% respectively, during hardening in the greenhouse for a 6-week period. 相似文献
13.
Organogenic cultures were induced from zygotic embryo and megagametophyte explants of the Central American cycad species,
Dioon edule. Plant growth medium consisted of B5 major salts, Murashige and Skoog minor salts and organics, 400 mg l−1 glutamine, 100 mg l−1 arginine, 100 mg l−1 asparagine, 60 g l−1 sucrose, 8 g l−1 Difco Bacto agar and was supplemented with kinetin (0 – 13.94 μM) and 2,4-dichlorophenoxyacetic acid (2,4-D) (0 – 9.05 μM)
arranged as a 5×4 factorial in a randomized block design. Callus initiation occurred on a wide range of medium formulations
from megagametophyte explants; however, shoot formation occurred only on medium supplemented with 2.26 μM 2,4-D. In comparison,
callus initiation from explanted zygotic embryos occurred on fewer medium formulations, and adventitious shoot induction occurred
from callus on formulations with 9.29–13.94 μM kinetin + 0.45–9.05 μM 2,4-D. Rooted shoots, derived from megagametophyte and
zygotic embryo cultures, have been regenerated.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
14.
Leaf explants of Jatropha curcas cultured on Murashige and Skoog’s (MS) medium supplemented with thidiazuron (TDZ; 0.90 μM) in combination with indole-3-butyric
acid (IBA; 0.98μM) produced adventitious shoot buds directly on the surface of the explants without formation of intervening
callus while shoot bud formation was accompanied with callus formation on medium supplemented with 6-benzylaminopurine (BAP;
13.3 μM) and IBA (2.46 μM). TDZ treatment resulted in more than twice higher rate of shoot bud induction than BAP. Shoot buds
were multiplied and elongated following repeated transfers to medium containing BAP (2.22 μM) and gibberellic acid (GA3; 1.44 μM). The effect of copper sulphate on differentiation of shoot buds from leaf segments was also investigated. Both
shoot induction and multiplication media were supplemented with different levels of CuSO4 (0–5 μM). Significant improvement in shoot bud induction was observed when the concentration of CuSO4 was increased to 10 times the normal MS level. Healthy elongated shoots were rooted on half strength MS medium supplemented
with IBA (2.46 μM). Rooted plantlets were transferred to field and survived. Histological analysis revealed direct formation
of shoot buds from leaf explants. 相似文献
15.
Ammonium and nitrate uptake by Laminaria saccharina and Nereocystis luetkeana originating from a salmon sea cage farm 总被引:4,自引:0,他引:4
In the laboratory, ammonium and nitrate uptakes were measured for juvenile Laminaria saccharina (L.) Lamour. and Nereocystis
luetkeana (Mert.) Post. et Rupr. originating from a salmon sea cage farm in northwestern British Columbia, Canada. The effect
of various concentrations of NH4+ and NO3-, which are typical of salmon farming environments, on uptakes values were examined.
Both L. saccharina and Nereocystis revealed simultaneous uptake of NH4+ and NO3- when both NH4+ and NO3- were present in the
medium. During a 3-h incubation, mean uptake rates of NH4+ and NO3- by L. saccharina ranged from 6.0–8.9 and 4.6–10.6 μmol
gdw-1 h-1, respectively, and by Nereocystis, they ranged from 6.6–9.3 μmol gdw-1 h-1 and 6.1–17.0 μmol gdw-1 h-1, respectively.
The highest uptake rates (14.8 μmol NH4+ gdw-1 h-1by L. saccharina and 27.2 μmol NO3- gdw-1 h-1 by Nereocystis) occurred at
the highest concentration (40 μM NH4+ plus 30 μM NO3-) during a 1 h incubation. Nitrate uptake by both L. saccharina and Nereocystis
increased linearly up to the highest nitrate level tested (30 μM), whereas uptake rates of ammonium were stable beyond 10
μM NH4+ to reach approximately 10 and 13 μmol gdw-1 h-1, respectively, for L. saccharina and Nereocystis. Unlike L. saccharina,
Nereocystis showed a significant preference for NO3- when more than 20 μM NO3- was present in the medium ( p <0.05). Both
L. saccharina and Nereocystis would be suitable for integrated cultivation of salmon/kelp.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
16.
A rapid and efficient micropropagation system was developed for Psoralea corylifolia, an endangered, valuable medicinal plant. Multiple shoot buds were obtained in half-strength liquid Phillips–Collins (L2)
medium supplemented with 5 μM benzylaminopurine (BA) and 5 μM thidiazuron (TDZ) from apical bud explants of 1-week-old cultures.
The shoot buds were subcultured on enriched solid L2 medium supplemented with different concentrations and combinations of
BA, kinetin (KIN), 2-isopentenyladenine (2iP), TDZ, bavistin (BVN) and trimethoprim (TMP). Enriched solid L2 medium supplemented
with 2 μM BA, 1 μM TDZ and 100 mg l−1 BVN were more effective in producing greater number of shoots per explant (85.2 ± 0.9 shoots/explant) after 4 weeks of culture.
The regenerated shoots (40–50 mm in length) rooted and accompanied by hardening upon transfer to 50 μM indole-3-butyric acid
(IBA) for 15 min and followed by planting in sterile soil mixture and vermiculate (3:1 v/v), with 50 ml of one-eight strength
L2 basal salt solution devoid of sucrose and inositol, supplemented with 5 μM IBA and 100 mg l−1 BVN. The plants achieved 100% rooting with hardening. Subsequently the rooted plants were successfully established in the
field. The survival percentage differed with seasonal variations. The concentration of psoralen was evaluated in different
tissues of ex vitro and in vivo grown plants by high-performance liquid chromatography (HPLC). Psoralen content was increased
in leaves (2.97%), roots (2.38%), stems (5.40%) and seeds (1.63%) of ex vitro plants than the in vivo plants. This system
facilitates for commercial and rapid propagation of P. corylifolia for conservation strategies and phytomedicine production. 相似文献
17.
L. Xu U. Najeeb R. Raziuddin W. Q. Shen J. Y. Shou G. X. Tang W. J. Zhou 《In vitro cellular & developmental biology. Plant》2009,45(5):610-618
Wetland species mat rush (Juncus effusus L.) is an important economic plant, but no information is available regarding plant regeneration, callus induction, and its
proliferation from in vitro seed grown plantlets. The present study investigates the effects of growth regulator combinations and medium innovation on
tissue culture system of five mat rush varieties. Addition of N6-benzyladenine (BA) and 2,4-dichlorophenoxyacetic acid (2,4-D)
in Murashige and Skoog (MS) medium showed significantly positive effect on callus proliferation, plant regeneration, and its
multiplication compared to the medium devoid of BA. The highest callus induction frequency (80.95%, 90.48%, 75.40%, 70.83%,
and 83.33%) was observed in MS medium containing 0.5 mg L−1 (2.2 μM) BA in Yinlin-1, Nonglin-4, Gangshan, Taicao, and Taiwan green, respectively. Various growth regulator combinations
with successive subculture (medium replacement) were found essential to develop organogenic calluses and to regenerate shoots.
The combination of 0.1 mg L−1 BA (0.4 μM) and 2 mg L−1 2,4-D (9.0 μM) in MS medium was found best for callus proliferation for all the varieties under trial. The plant regeneration
required two steps involving successive medium replacements as well as optimal hormonal balances. Successful plant regeneration
(over 70%) was observed only by transferring the organogenic callus from regeneration medium I [MS medium containing 0.5 mg
L−1 BA (2. μM) and 1.0 mg L−1 kinetin (KT; 4.6 μM)] to the regeneration medium II [MS medium containing 0.5 mg L−1 BA (2.2 μM), 1.0 mg L−1 KT (4.6 μM) and 3.0 mg L−1 indoleacetic acid (IAA; 17.1 μM)]. Our results confirmed the importance of the ratio of auxin (IAA) to cytokinin (BA and
KT) in the manipulation of shoot regeneration in J. effusus L. The maximum plant survival frequency and multiplication rates (90.97% and 5.40 and 94.23% and 8.25) were recorded in the
presence of 0.5 mg L−1 BA (2.2 μM) in the 1/2 MS multiplication medium for the varieties of Nonglin-4 and Taicao, respectively. About 100% survival
rate was also observed for all the varieties in soil conditions. The efficient plant regeneration system developed here will
be helpful for rapid micropropagation and further genetic improvement in J. effusus L. 相似文献
18.
Regeneration from petioles and leaf blades was studied for seven genotypes of Pelargonium peltatum. Multiple adventitious
shoots were produced using wide range of thidiazuron concentrations. Somatic embryos were produced from callus-derived cell
suspensions from 3 genotypes, with a combination of 0.45 μM thidiazuron and 20 μM α-naphthaleneacetic acid in liquid medium.
Regenerants were rooted and transferred to soil where they showed a normal phenotype.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
19.
The effect of zinc on various pulmonary cell lines has been studied by measuring the depletion of total cellular glutathione
after exposure to zinc(II) chloride at different concentrations.
Total cellular glutathione (cGS) was measured at 31 ± 3 nmol/mg, 3.8 ± 0.6 nmol/mg, and 3.7 ±1.2 nmol/mg protein in A549,
L2, and 11Lu cells, respectively. After treatment with buthionine sulfoximine (BSO), the cGS levels decreased by 20% in A549
cells and below 0.2 nmol/mg in L2 and 11Lu cells.
Exposure of A549 cells to 25–200 μM ZnCl2 for 4 h alone decreased the cGS content to 60–80%. There was little additional effect in BSO-pretreated cells. In L2 and
11Lu cells, the decrease of cGS was 70–85% following exposure to 15–150 μM ZnCl2 for 2 h. If BSO was also used, the decrease in cGS was 85–95% in L2 cells and 75–85% in 11Lu cells.
Exposure to 25–250 μM ZnCl2 for 2 h diminished protein synthesis as determined by radiolabeled methionine incorporation, with half-maximum inhibition
(EC50) from 40–160 μM ZnCl2. To attain similar EC50 values in BSO-pretreated cells, only about half the zinc concentrations were required as compared to cells without pretreatment.
The decrease of cGS was accompanied by an increased ratio of oxidized : reduced glutathione that was more pronounced in cells
with low glutathione content. 相似文献
20.
Embryogenic cultures were induced from leaflets from new vegetative flushes of mature ‘Brewster’ litchi trees on B5 medium
containing 400 mg l−1 glutamine, 200 mg l−1 casein hydrolysate, 30 g l−1 sucrose, 4.52 μM 2,4-D, 9.30 μM kinetin and 3 g l−1 gellan gum in darkness. Embryogenic cultures consisting of proembryonic cells and masses were maintained either on semi-solid
MS medium supplemented with 4.52 μM 2,4-D and 0.91 μM zeatin or as embryogenic suspension cultures in liquid medium of the
same composition. Maturation of somatic embryos occurred on semi-solid MS medium with 5–20% (v/v) filter-sterilized coconut
water in darkness. Recovery of plants from somatic embryos was improved with 14.4 μM GA3 on half-strength MS medium with 0.2 g l−1 activated charcoal under a 16 h photoperiod provided by cool white fluorescent lights (60–80 μmol s−1 m−2). Plants have been successfully acclimatized in the greenhouse. 相似文献