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1.
2.
The sepal color of a chameleon hydrangea, Hydrangea macrophylla cv. Hovaria™ ‘Homigo’ changes in four stages, from colorless to blue, then to green, and finally to red, during maturation and the senescence periods. To clarify the chemical mechanism of the color change, we analyzed the components of the sepals at each stage. Blue-colored sepals contained 3-O-sambubiosyl- and 3-O-glucosyldelphinidin along with three co-pigments, 5-O-p-coumaroyl-, 5-O-caffeoyl- and 3-O-caffeoylquinic acids. The contents of glycosyldelphinidins decreased toward the green-colored stage, with a coincident increase in the number of chloroplasts. During the last red colored stage, the two species of 3-O-glycosyldelphinidin almost disappeared, and another two anthocyanins, 3-O-sambubiosyl- and 3-O-glucosylcyanidin, increased in amounts. Mixing of 3-O-glycosylcyanidins, co-pigments, and Al3+ in a buffered solution at pH 3.0-3.5 gave not a blue, but a red, colored solution that was the same as that of the sepal color of the 4th stage. Sepals of hydrangea grown in an highland area also turned red in autumn, and contained the same cyanidin glycosides. The red coloration of the hydrangea during senescence was due to a change in anthocyanin biosynthesis. 相似文献
3.
Aluminum in lake water and in the organs of the fish Tribolodon hakonensis was investigated in Lake Usoriko (pH 3.6), Lake Inawashiroko (pH 5.0), and the Tenryu River (pH 7.7). The concentration of
total soluble aluminum in the water was 0.51 mg l−1 in Usoriko, 0.05 mg l−1 in Inawashiroko, and less than 0.01 mg l−1 in the Tenryu. The chemical forms of soluble aluminum in the acid water were characterized as Al3+, AlL2+, and AlL≦1+. More than 90% of soluble aluminum in the water of Usoriko was Al3+, whereas AlL2+ was dominant in the water of Inawashiroko. The aluminum concentration in the organs of T. hakonensis in Usoriko was 42 μg g−1 wet weight in gills, 4.2 μg g−1 in muscle, 6.9 μg g−1 in bone, 12.7 μg g−1 in liver, 6.0 μg g−1 in kidney, and 6.0 μg g−1 in intestine, indicating accumulation of aluminum in the gills. The aluminum concentration in the organs of T. hakonensis living in Inawashiroko was approximately the same, in spite of the difference in water chemistry of the two acid lakes, especially
for pH and aluminum. This suggests that aluminum accumulation might be controlled in the fish living in the acid lakes. In
contrast, the aluminum concentration in the gills of T. hakonensis from the Tenryu was 2 μg g−1.
Received: May 20, 1999 / Accepted: December 10, 1999 相似文献
4.
报道了中国云南省兰科(Orchidaceae)兜兰属(Paphiopedilum)一新天然杂交种:哀牢山兜兰(Paphiopedilum×ailaoshanense B. Liu & S. P. Chen)。哀牢山兜兰与白旗兜兰(P. spicerianum)和沧源兜兰(P. gratrixianum var. cangyuanense)近缘,与前者的区别在于哀牢山兜兰花梗和子房有毛,中萼片带紫色晕以及紫色斑点,花瓣上侧暗绿色带紫色晕,下侧黄绿色;与后者的区别在于中萼片具1条宽阔的紫褐色中带,退化雌蕊紫色。哀牢山兜兰与天然杂种泸水兜兰(Paphiopedilum×lushuiense)相似,而哀牢山兜兰的中萼片下部边缘不后卷,近基部具紫红色晕,合萼片具2条明显紫色粗脉,花瓣匙形,上边缘波状,长6.0~6.2 cm,唇瓣长5.0~5.5 cm。为厘清哀牢山兜兰,沧源兜兰及白旗兜兰之间的关系,基于3个叶绿体基因片段(matK、rbcL、trnL),构建了兜兰属部分植物系统发育树。鉴于形态和分子数据,认为哀牢山兜兰是天然杂交种。凭证标本存放于福建农林大学标本馆。 相似文献
5.
From blue sepals of Hydrangea macrophylla, copigments which show a blueing effect on the hydrangea anthocyanin were isolated and identified as 3-p-coumaroylquinic acid and 3-caffeoylquinic acid. 5-Caffeoylquinic acid (chlorogenic acid) which was also found in the blue sepals, however, did not show such a blueing effect though it acted as a copigment. Likewise, the 4-esters of p-coumaroyl- and caffeoylquinic acids (not found in sepals) produced purple rather than blue colours. The facts suggest that the stereostructures of 3-p-coumaroyl- and 3-caffeoylquinic acids are effective for molecular interaction between the p-coumaroyl or caffeoyl residue in the compounds and the anthocyanin. The anthocyanin in red and blue sepals of hydrangea was confirmed to be delphinidin 3-monoglucoside. 相似文献
6.
Blue and red sepals of Hydrangea macrophylla were quantitatively analyzed for aluminium, anthocyanin (delphinidin 3-glucoside) and copigments (caffeoyl- and p-coumaroylquinic acids). All the blue sepals examined contained both Al and copigments (especially 3-caffeoylquinic acid) in considerable amounts. In in vitro experiments using 3- and 5-caffeoylquinic acids, Al and delphinidin 3-glucoside, it was shown that 3-caffeoylquinic acid and Al formed a blue complex with the anthocyanin. Absorption spectra of the blue complex were practically identical with those of the blue solutions obtained from blue hydrangea sepals by extraction with 4 M NACl. In contrast, 5-caffeoylquinic acid (chlorogenic acid) which was also present in hydrangea sepals gave only a red-purple colour with Al and the anthocyanin. Neither 3-caffeoylquinic acid nor Al independently produced blue colour when mixed with the anthocyanin in the mole ratios of 1–30, this being the range that the compounds were found in blue sepals. These results suggest that blue colour of hydrangea sepals is due mainly to the blue complex of delphinidin 3-glucoside-aluminium-3-caffeoylquinic acid. The role of aluminium may be to stabilize an interaction between the quinic ester and the anthocyanin. 相似文献
7.
Chloroplast photorelocation movement is important for plants to perform efficient photosynthesis. Phototropins were identified
as blue-light receptors for chloroplast movement in Arabidopsis thaliana and in the fern Adiantum capillus-veneris, whereas neochrome functions as a dual red/blue light receptor in the latter. However, the signal transduction pathways involved
in chloroplast movement remain to be clarified. To investigate the kinetic properties of signalling from these photoreceptors
to the chloroplasts, we deduced the speed of signal transfer using Adiantum capillus-veneris gametophytes. When a region of dark-adapted gametophyte cells was subjected to microbeam irradiation, chloroplasts moved
towards the irradiated area even in subsequent darkness. We therefore recorded the movement and calculated the speeds of signal
transfer by time-lapse imaging. Movement speeds under red or blue light were similar, e.g., about 1.0 μm min−1 in prothallial cells. However, speeds varied according to cell polarity in protonemal cells. The speed of signal transfer
from the protonemal apex to the base was approximately 0.7 μm min−1, but roughly 2.3 μm min−1 in the opposite direction. The speed of signal transfer in Arabidopsis thaliana mesophyll cells was approximately 0.8 μm min−1 by comparison. Surprisingly, chloroplasts located farthest away from the microbeam were found to move faster than those in
close proximity to the site of irradiation both in Adiantum capillus-veneris and A. thaliana. 相似文献
8.
The Alternaria mycotoxin tenuazonic acid (TA) was quantified in fruit juices (n = 50), cereals (n = 12) and spices (n = 38) using a recently developed stable isotope dilution assay (SIDA). [13 C6,15 N]-TA was used as the internal standard. Method validation revealed low limits of detection (LODs) of 0.15 μg/kg (fruit juices),
1.0 μg/kg (cereals) and 17 μg/kg (spices). The respective limits of quantitation were about three times higher. Recovery was
about 100% for all matrices. The precision (relative standard deviation of replicate analyses of naturally contaminated samples)
was 4.2% (grape juice; 1.7 μg/kg), 3.5% (whole wheat flour; 36 μg/kg) and 0.9% (curry powder; 215 μg/kg). The median content
of TA in the analyzed samples was 1.8 μg/kg (fruit juices), 16 μg/kg (cereals) and 500 μg/kg (spices). Positive samples amounted
to 86% (fruit juices), 92% (cereals) and 87% (spices). 相似文献
9.
The effects of low concentrations of aluminium on the growth and uptake of nitrate-N by white clover 总被引:1,自引:0,他引:1
Summary The effects of aluminium (Al3+) at concentrations of 0, 25, 50 and 100 μM on the growth of white clover, dependent upon N supplied as NO
3
−
, were examined in flowing solution culture. Plants were established with a normal nutrient supply for 7 weeks and then grown
with carefully controlled pH (at 4.5) and P concentrations, and with 0, 25, 50 or 100 μM Al3+ for a further three weeks. There were rapid visual effects (i.e. symptoms of P deficiency and reduction in root extension) and the dry weights of shoots and roots were reduced at 50 and
100 μM. Less than 10% of Al absorbed from solution was transported to the shoots. The uptake of P, and its transport between roots
and shoots, were reduced in plants grown with Al. The uptake of NO
3
−
stopped immediately after the introduction of 50 or 100 μM Al, and was significantly reduced at 25 μM after three weeks.
During a second phase of the experiment, plants previously grown at 0, 25, 50 and 100 μM Al, were grown for a further 2 weeks either with NO
3
−
(with and without 50 μM Al3+) or without NO
3
−
but with inoculation by Rhizobia (and with or without 50 μM Al3+). The effects of the previous treatments with Al on N uptake were small during the second phase, but uptake by all plants
was restricted when Al was present. Inoculation did not result in nodulation in the second phase when Al3+ was present in the solution, but Al already in the plant from the first phase did not prevent nodulation in the absence of
Al during the second phase. 相似文献
10.
Anželika Kurilčik Renata Miklušytė-Čanova Stasė Dapkūnienė Silva Žilinskaitė Genadij Kurilčik Gintautas Tamulaitis Pavelas Duchovskis Artūras Žukauskas 《Central European Journal of Biology》2008,3(2):161-167
Effects of illumination spectrum on the morphogenesis of chrysanthemum plantlets (Chrysanthemum morifolium Ramat. ‘Ellen’) grown in vitro were studied using an illumination system consisting of four groups of light-emitting diodes (LEDs) in the following spectral
regions: blue (450nm), red (640nm), red (660nm), and far-red (735nm). Taking into account all differences in shoot height,
root length, and fresh and dry weight (FW and DW, respectively), observed while changing the total photon flux density (PFD),
the optimal total PFD for growth of chrysanthemum plantlets in vitro was estimated. For 16 h photoperiod and typical fractions of the spectral components (14%, 50%, 28%, and 8%, respectively),
the optimal total PFD was found to be 40 μmol m−2 s−1. Our study shows that the blue component in the illumination spectrum inhibits the plantlet extension and formation of roots
and simultaneously increases the DW to FW ratio and content of photosynthetic pigments. We demonstrate photomorphogenetic
effects in the blue region and its interaction with the fractional PFD of the far-red spectral component. Under constant fractional
PFD of the blue component, the root number, length of roots and stems, and fresh weight of the plantlets have a correlated
nonmonotonous dependence on the fractional PFD of the far-red component. 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.
Luis Arigita Ma Jesús Cañal Ricardo Sánchez Tamés Aida González 《In vitro cellular & developmental biology. Plant》2010,46(3):312-322
In traditional in vitro culture, the low CO2 concentration inside the vessels restricts photosynthesis and necessitates the addition of sucrose to the culture medium
as the main energy source, thus bringing about changes in the absorption of mineral elements from the culture medium. In this
study, we investigated macronutrient absorption and sugar consumption in Actinidia deliciosa Chevalier Liang and Ferguson cv. Hayward (kiwi), cultured on medium supplemented with varying amounts of sucrose (0, 10,
and 20 g l−1) under both heterotrophy and autotrophy, flushed with different concentrations of CO2 (non-ventilation, 300, 600, and 2,000 μl l−1). In ventilated systems with 20 g l−1 of sucrose, sucrose absorption was less than under non-ventilation. The lowest rate of sucrose absorption was recorded when
the explants were cultured on medium supplemented with 20 g l−1 of sucrose and flushed with 600 μl l−1 CO2. Absorption of NO3
−, PO4
3−, and Mg2+ were high (maximum) at the end of the culture period (40 d) in explants flushed with 600 μl l−1 CO2 that have been cultured 20 d in the presence of sucrose and then transferred to a sucrose-free medium. These autotrophic
conditions promoted maximum plant growth in terms of both fresh and dry mass as well as the length and number of shoots and
leaves. The study shows that to maintain an optimum regime of mineral nutrition for prolonged culture of kiwi in vitro, an increased amount of these three ions should be supplemented in Murashige and Skoog’s medium. 相似文献
13.
Pueraria tuberosa, a medicinally important leguminous plant, yielding various isoflavanones including puerarin, is threatened, thus requiring
conservation. In this study, fresh shoot sprouts of P. tuberosa, produced by tubers, were used as explants for in vitro micropropagation. Surface-sterilized nodal shoots were incubated
on Murashige and Skoog (MS) medium supplemented with 8.88 μM benzyladenine (BA), 50 mg l−1 ascorbic acid, and 25 mg l−1 of each of citric acid and adenine sulphate. Cut ends of nodal stem segments rapidly turned brown, and cultures failed to
establish. When 100 mg l−1 ascorbic acid (ABA) and 25.0 mg l−1 polyvinyl pyrrolidone (PVP) were added to the medium, explants remained healthy, and cultures were established. Bud-breaking
of nodal stem explants resulted in multiple shoot formation. Shoots proliferated (35–40 shoots per culture vessel) on MS medium
as described above, but supplemented with 4.44 μM BA and 0.57 μM indole acetic acid (IAA) and additives. After 4–5 passages,
proliferating shoots exhibited tip-browning and decline in growth and multiplication. However, when shoots were transferred
to fresh shoot proliferation medium supplemented with 2.32 μM kinetin (Kn), sustained growth and high rate of shoot proliferation
(50–60 shoots per culture vessel) was observed. Shoots rooted when transferred to medium consisting of half- strength MS medium
with 9.84 μM indole butyric acid (IBA) and 0.02% activated charcoal. Alternatively, individual shoots were pulsed with 984.0 μM
IBA and transferred to glass bottles containing sterile and moistened soilrite. These shoots rooted ex-vitro and were acclimatized
in the greenhouse. Plants were then analyzed for puerarin content using HPLC, and leaves showed maximum accumulation of purerarin. 相似文献
14.
The objective of this study was to determine the effects of different light-emitting diode (LED) light sources on the growth
of upland cotton (Gossypium hirsutum L.) plantlets. Shoot bud apex cuttings of upland cotton (1.0 cm) were transplanted on Murashige and Skoog (MS) basal medium
supplemented with 0.1 mg/l 6-benzyladenine (BA) and 0.5 mg/l naphthalene acetic acid (NAA) and cultured in vitro for 45 days.
They were exposed to 50 μmol m−2 s−1 photosynthetic photon flux (PPF) and a 12-h photoperiod under six different lights: fluorescent lamp (CON), monochromatic
blue LED (B), three blue and red LED mixtures (B:R = 3:1, 1:1, 1:3) and monochromatic red LED (R). The effects of the six
light sources on growth and morphogenesis of upland cotton plantlets grown in vitro were investigated. Fresh weight, dry weight,
stem length and second internode length were greatest in plantlets cultured under the B:R = 1:1 blue and red LED light, followed
by blue LED light, and they were lowest in plantlets cultured under a fluorescent lamp. Chlorophyll content, leaf thickness,
palisade tissue length, leaf and stomata area were highest in plantlets cultured under blue LED light. Root activity, sucrose,
starch and soluble sugar contents were highest in plantlets cultured under red LED light. Our results showed that larger,
healthier plantlets and a greater biomass of upland cotton were produced in the presence of red LED supplemented with a quantity
of blue LED light. Blue and red LED (B:R = 1:1) was the most suitable light for the growth of upland cotton plantlets in vitro,
and it may be used as alternative light source for an upland cotton culture system. 相似文献
15.
The aim of this work was to assess the effect of leaf thickness, leaf succulence (LS), specific leaf area (SLA), specific leaf mass (Ws) and leaf water content (LWC) on chlorophyll (Chl) meter values in six Amazonian tree species (Carapa guianensis, Ceiba pentandra, Cynometra spruceana, Pithecolobium inaequale, Scleronema micranthum and Swietenia macrophylla). We also tested the accuracy of a general calibration equation to convert Minolta Chl meter (SPAD-502) readings into absolute Chl content. On average, SPAD values (x) increased with fresh leaf thickness (FLT [μm] = 153.9 +
0.98 x, r
2 = 0.06**), dry leaf thickness (DLT [μm] = 49.50 + 1.28 x, r
2 = 0.16**), specific leaf mass (Ws [g (DM) m−2] = 6.73 + 1.31 x, r
2 = 0.43**), and leaf succulence (LS [g(FM)] m−2 = 94.2 + 1.58 x, r
2 = 0.19**). However, a negative relationship was found between SPAD values and either specific leaf area [SLA (m2 kg−1) = 35.1 − 0.37 x, r
2 = 0.38**] or the leaf water content (LWC [%]= 80.0 − 0.42 x, r
2 = 0.58**). Leaf Chl contents predicted by the general calibration equation significantly differed (p<0.01) from those estimated by species-specific calibration equations. We conclude that to improve the accuracy of the SPAD-502 leaf thickness and LWC should be taken into account when calibration equations are to be obtained to convert SPAD values
into absolute Chl content. 相似文献
16.
N. Tang H. -X. Jiang L. -T. Yang Q. Li G. -H. Yang L. -S. Chen 《Biologia Plantarum》2011,55(4):681-688
Sour pummelo (Citrus grandis) seedlings were irrigated with nutrient solution containing four boron concentrations (i.e., 2.5, 10, 25 and 50 μM H3BO3) and two aluminum concentrations [i.e., 0 (-Al) and 1.2 mM AlCl3 · 6 H2O (+Al)]. It was found that B did not affect, but Al increased, the Al content in the roots. The Al and citrate contents in
the -Al leaves either did not change or slightly increased with increasing B concentration. On the other hand, the Al and
citrate contents in the +Al leaves rapidly decreased as B concentration increased from 2.5 to 50 μM, then decreased at the
highest B concentration. The Al and citrate contents were higher in the +Al than in the -Al leaves, except for at 25 μM B
when they were similar. The leaf malate content did not change in response to B or Al, except for an increase in the +Al leaves
and a decrease in the -Al leaves at 2.5 μM B. Similarly, the root malate and citrate contents did not change in response to
B with or without Al, except for a decrease in the malate and citrate contents in the +Al roots at 50 μM B and an increase
in the citrate content in the -Al roots at 50 μM B. The activities of acid-metabolizing enzymes were less affected by B-Al
interactions in the roots than in the leaves. 相似文献
17.
Michael R. McHale Douglas A. Burns Gregory B. Lawrence Peter S. Murdoch 《Biogeochemistry》2007,84(3):311-331
The 24 ha Dry Creek watershed in the Catskill Mountains of southeastern New York State USA was clearcut during the winter
of 1996–1997. The interactions among acidity, nitrate (NO3−), aluminum (Al), and calcium (Ca2+) in streamwater, soil water, and groundwater were evaluated to determine how they affected the speciation, solubility, and
concentrations of Al after the harvest. Watershed soils were characterized by low base saturation, high exchangeable Al concentrations,
and low exchangeable base cation concentrations prior to the harvest. Mean streamwater NO3− concentration was about 20 μmol l−1 for the 3 years before the harvest, increased sharply after the harvest, and peaked at 1,309 μmol l−1 about 5 months after the harvest. Nitrate and inorganic monomeric aluminum (Alim) export increased by 4−fold during the first year after the harvest. Alim mobilization is of concern because it is toxic to some fish species and can inhibit the uptake of Ca2+ by tree roots. Organic complexation appeared to control Al solubility in the O horizon while ion exchange and possibly equilibrium
with imogolite appeared to control Al solubility in the B horizon. Alim and NO3− concentrations were strongly correlated in B-horizon soil water after the clearcut (r
2 = 0.96), especially at NO3− concentrations greater than 100 μmol l−1. Groundwater entering the stream from perennial springs contained high concentrations of base cations and low concentrations
of NO3− which mixed with acidic, high Alim soil water and decreased the concentration of Alim in streamwater after the harvest. Five years after the harvest soil water NO3− concentrations had dropped below preharvest levels as the demand for nitrogen by regenerating vegetation increased, but groundwater
NO3− concentrations remained elevated because groundwater has a longer residence time. As a result streamwater NO3− concentrations had not fallen below preharvest levels, even during the growing season, 5 years after the harvest because
of the contribution of groundwater to the stream. Streamwater NO3− and Alim concentrations increased more than reported in previous forest harvesting studies and the recovery was slower likely because
the watershed has experienced several decades of acid deposition that has depleted initially base-poor soils of exchangeable
base cations and caused long-term acidification of the soil. 相似文献
18.
S. A. Webster S. A. Mitchell W. A. Gallimore L. A. D. Williams M. H. Ahmad 《In vitro cellular & developmental biology. Plant》2008,44(2):112-118
A procedure for producing somatic embryos enriched with dibenzyl trisulfide (DTS) using a hormone-dependent culture system
is reported for Petiveria alliacea L. (Guinea hen weed). Leaf explants were cultured on a Murashige and Skoog medium supplemented with a range of naphthaleneacetic
acid (NAA) concentrations and a fixed concentration of benzyladenine (BAP) at 11.0 μM and sucrose or glucose at 30 g l−1. Leaf explants cultured on all media types started to form callus at the cut surfaces of the discs 10–14 d after initiation.
The type of sugar used influenced average fresh weight, the propensity to form roots, as well as the embryogenic response.
The highest mean fresh weight (337.7 ± 26.18 mg) and mean root number (23.7 ± 1.69) was produced on media enriched with sucrose
and supplemented with 53.7 μM NAA and 11.0 μM BAP. An ethanol extract of rhizogenic/embryogenic callus or somatic embryos
was subjected to high-performance liquid chromatography analysis, which revealed the presence of DTS in both extracts. UV
spectral analysis and the use of standard quantitation procedures showed that the quantity of DTS in the somatic embryo extract,
at 0.16% (w/v), was approximately 30-fold higher than in rhizogenic/embryogenic callus (0.0055% w/v) of similar fresh weight. These results indicate that it is possible to biosynthesize approximately 6 mg of natural DTS from
3,808 mg of fresh somatic embryos within 10 wk from less than three leaf explants. 相似文献
19.
Arsenic content of cyanobacterial biomass, soil and water samples from arsenic-contaminated area of eastern India were estimated.
It was found that arsenic content in cyanobacterial biomass (276.9 μg g−1) was more than soil (19.01 μg g−1) or water sample (244.13 μg L−1). Shallow tube well water showed more arsenic (244.13 μg L−1) than deep tube well water (146.13 μg L−1). Arsenic resistant genera recorded from the contaminated area were Oscillatoria princeps, Oscillatoria limosa, Anabaena sp. and Phormidium laminosum. Among these, P. laminosum was isolated and exposed to different concentration of Arsenic in vitro (0.1–100 ppm) to study the toxicity level of arsenic.
Modulation in stress enzymes and stress-related compounds were studied in relation to lipid peroxidase, catalase, super oxide
dismutase (SOD), ascorbate peroxidase (APX), reduced glutathione and carotenoids in arsenic exposed biomass to understand
the resistance mechanism of the genus both in laboratory condition as well as in natural condition. Arsenic content of cyanobacterial
biomass from contaminated area was more (276.9 μg g−1) than laboratory exposed sample (37.17 μg g−1), indicating bioconcentration of arsenic in long-term-exposed natural biomass. Overall, more activity of catalase was recorded
in cyanobacterial biomass of natural condition whereas SOD and APX were at higher level in laboratory culture. 相似文献
20.
Ling Ding Xi Li Peng Liu Shiqian Li Jiliang Lv 《Biological trace element research》2010,137(3):364-372
The biological effect of Se and Cu2+ on Escherichia coli (E. coli) growth was studied by using a 3114/3236 TAM Air Isothermal Calorimeter, ampoule method, at 37°C. From the thermogenesis
curves, the thermokinetic equations were established under different conditions. The kinetics showed that a low concentration
of Se (1–10 μg/mL) promoted the growth of E. coli, and a high concentration of Se (>10 μg/mL) inhibited the growth, but the Cu2+ was always inhibiting the growth of E. coli. Moreover, there was an antagonistic or positive synergistic effect of Se and Cu2+ on E. coli in the different culture medium when Se was 1–10 μg/ml and Cu2+ was 1–20 μg/ml. There was a negative synergistic effect of Se and Cu2+ on E. coli when Se was higher than 10 μg/ml and Cu2+ was higher than 20 μg/ml. The antagonistic or synergistic effect between Se and Cu2+ on E. coli was related to the formation of Cu–Se complexes under the different experimental conditions chosen. 相似文献