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1.
A component (s-factor) with obvious promoting effect on hydrogen evolution of hydrogenase has beenisolated and extracted from a Cell=free preparation of Spirulina platensis.The effect of the s-factor in the re-action system is similar to that of Na_2S_2O_4, but is coupled with ligh. The s-factor has the maximumabsorption peak at 620 nm in the oxidized state, at 590 nm in the reduced state. The partially purifieds-factor showed two bands by SDS-PAGE and is distinctly different from phycocyanin,which has nochange of oxidized state and reduced state absorption spectra, and also has no promoting effect onhydrogenase of Spirulina platensis under the light. 相似文献
2.
Cao Ji-xiang 《中国海洋湖沼学报》1996,14(4):378-386
This study on the effect of different concentrations of germanium dioxide (GeO2) on the specific growth rate (SGR), pigment contents, protein content and amino acid composition ofSpirulina platensis showed that Ge was not the essential element of this alga; that GeO2 could speed up growth and raise protein content ofS. platensis, and could possibly influence the photosynthesis system. The concentration range of GeO2 beneficial to growth ofS. platensis is from 5–100mg/l. GeO2 is proposed to be utilized to remove contamination byChlorella spp. usually occurring in the cultivation ofSpirulina. 相似文献
3.
CCC plasmid was isolated from an economically important blue-green alga —Spirulina platensis (1.7×106 dalton from the S6 strain and 1.2×106 dalton from the F3 strain) using a rapid method based on ultrasonic disruption of algal cells and alkaline removal of chromosomal DNA. The difference
in the molecular weight of the CCC DNAs from the two strains differing in form suggests that plasmid may be related with the
differentiation of algal form. This modified method, which does not use any lysozyme, is a quick and effective method of plasmid
isolation, especially for filamentous blue-green algae.
Contribution No. 79 of the Experimental Marine Biology Laboratory and 2153 of the Institute of Oceanology, Academia Sinica.
This research was supported in part by The President of the Chinese Academy of Sciences Foundation. 相似文献
4.
A laboratory experiment was conducted to assess the bioaccumulation of Pb2+ and its effects on growth, morphology and pigment contents of Spirulina (Arthrospira) platensis. The specimen cultured in Zarrouk liquid medium was treated with various initial metal concentrations (0, 5, 10, 30, 50 and
100 μg mL−1). The growth of S. platensis was adversely affected by Pb2+ at high concentrations (30, 50 and 100 μg mL−1). However, at low concentrations (5 μg mL−1), Pb2+ could stimulate its growth slightly. The pigment contents (chlorophyll α and β carotene) were decreased in a dose-dependent
manner. The highest reductions (67% and 53% respectively in chlorophyll α and β carotene) were observed in 100 μg mL−1 treatment group. The LC50 (96 h) of Pb2+ was measured as 75.34 μg mL−1. Apart from a few cases of filament breakages at elevated concentrations (50 and 100 μg mL−1), morphological abnormalities are not specific. Metal bioaccumulation increased with Pb2+ concentrations, but decreased with exposure time. The maximum accumulated amount was 188 mg g−1 dry weight. The bioconcentration factor (BCF) reached to a peak at day 2, followed by a gradual reduction for all the exposure
concentrations. S. platensis is able to tolerate considerably high Pb2+ concentrations. Consequently it can be used as a potential species to remove heavy metal from contaminated waters. 相似文献
5.
A spectral method to investigate the effect of Fe3+, Fe2+ on the thermostability of phycocyanin (PC) ofSpirulina maxima showed that iron ions provent decrease of visible light absorbance and fluorescence intensity of PC. Increase in denaturation temperature caused by Fe3+ was observed by the micro-differential scanning calorimetric method. All results showed iron ions maintain the aggregation stability of the PC. The absorption spectrum of phycocyanobilin (PCB, a prosthetic group of PC) with Fe3+ in chloroform was quite different from that of free PCB.
相似文献6.
Kojima Hiroyuki Song Qin Ajith Kumar Thankappan Kawata Yoshikazu Yano Shin-ichi 《中国海洋湖沼学报》1998,16(1):30-39
Transposable elements in cyanobacteria are briefly reviewed. Evidence is presented to show that transposable elements inSpirulina platensis is actually reflected on the phenotype change, i e., helical to straight filaments. Transposition intermediates of DNA were isolated from the extrachromosome and the transposition was related to helical variations inSpirulina. Uses of transposable elements for microalgal recombination are discussed based on the transposition mechanism.
相似文献7.
The genes coding for the α-and β-subunit of allophycocyanin (apcA andapcB) from the cyanophyteSpirulina maxima were cloned and sequenced. The results revealed 44.4% of nucleotide sequence similarity and 30.4% of similarity of deduced amino acid sequence between them. The amino acid sequence identities betweenS. maxima andS. platensis are 99.4% for α subunit and 100% for β subunit.
相似文献8.
Laminaria gametophyte was greatly influenced by light in its growth and development. Using light-emitting diodes (LED) as blue and
red light sources, we analyzed the light effect on gametophytes development ofLaminaria japonica Aresch. The gametophytes were obtained from zoospores collected in April, May, July, 2003 and September, 2004. We found that
the growth of gametophytes was stimulated by increasing intensity of blue light (BL) and red light (RL) illumination, of which
BL was obviously stronger than that of RL. The fertilization of gametophytes depended largely on BL, and only sufficient BL
illumination could take the reproductive effect. In addition, we noticed that there was a significant difference in light
responses for gametophytes developed from zoospore collected in different times. For zoospores released in April, under BL1 (73.90 μmol photons/m·s), the unicellular female gametophytes and multi-cellular male gametophytes produced eggs and sperms
respectively, and further developed towards sporophytes. However, for gametophytes developed in May, July or September, they
became multi-cellular and never formed oogonia or antheridia. It is believed that theLaminaria sporangium maturation stage could affect the gametophytes reaction to BL under laboratory culture conditions. Therefore,
cryptochrome- or phototropin-like BL photoreceptors is probably involved in BL-induced development ofLaminaria gametophytes.
This research was supported by the NSFC (No.40376049) and Japan Society for the Promotion of Science (The Invitation Fellowship
for Research in Japan 2002). 相似文献
9.
Cultures of a blue-green algaSpirulina maxima (Setch. et Gard.) Geitler with various concentrations of Se in Zarrouk's medium showed that not higher than 40 mg/L Se could
promote its growth. The present experiments showed thatS. maxima grown under normal conditions, has an oxidant stress defence system for hydrogen peroxide (H2O2) removal, which is the Halliwell-Asada pathway. When 4 to 20 mg/L Se was added to the algal medium, this pathway was replaced
by a so-called Sestressed pathway containing GSH peroxidase (GSH-POD). As a result of the occurrence of both higher activity
of GSH-POD and lower levels of hydroxyl radical (OH·), the Se-stressed pathway scavenged H2O2 so effectively that the growth ofS. maxima was promoted by 4 to 20 mg/L Se. While GSH-POD activity of the alga disappeared at 40 mg/L Se, the recovery of ascorbate
peroxidase was observed. The lower levels of ascorbic acid and GSH made the Halliwell-Asada pathway for scavenging H2O2 less effective, while the highest activity of catalase might be responsible in part for the H2O2 removal, causing the level of OH· inS. maxima grown at 40 mg/L Se to be much higher than the OH· level in this alga grown at 4 to 20 mg/L Se, but lower than that in the
control. The OH· level changes caused the growth ofS. maxima cultured at 40 mg/L Se to increase slightly to close to that of the control. 相似文献
10.
1 INTRODUCTION The Yellow Sea and the East China Sea are typical coastal Case-II waters with high sediment load and complicate optical properties. The total absorption coefficient of sea water is one of the main parameters influencing the calculation of o… 相似文献
11.
This study showed that the combined effect of absorption of planktonic algae and water on water color shift can be simulated
approximately by the exponential function: Log(E
100cm
W
+E
100cm
Xch1
)=0.002λ−2.5 whereE
100 cm
W
,E
100cm
Xchl
are, respectively, extinction coefficients of seawater and chlorophyll—a (concentration is equal toX mg/m3), and λ (nm) is wavelength.
This empirical regression equation is very useful for forecasting the relation between water color and biomass in water not
affected by terrigenous material. The main factor affecting water color shift in the ocean should be the absorption of blue
light by planktonic algae. 相似文献
12.
Inorganic carbon utilization in the non-calcifying marine microalgae,Nannochloropsis oculata, Phaeodactylum tricornutum andPorphyridium purpureum was compared with high- and low-calcifying strains ofEmiliania huxleyi grown in artificial seawater medium aerated with either air (0.03% V/V CO2) or CO2-free air. For high-calcifying strain ofE. oculata andP. tricornutem, similar growth patterns were observed in air-and CO2-free air-grown cultures.P. purpureum showed a less final cell density in CO2-free air than in air-grown culture. However, low-calcifying strain ofE. huxleyi was able to grow only in air-grown culture, but not in CO2-free air-grown culture.
Measurements of alkalinity, pH, concentration of dissolved inorganic carbon (DIC) and free CO2 showed different patterns of DIC utilization. WithN. oculata, P. tricornutum andP. purpureum the pattern of DIC utilization was characterized by an increase of pH and a decrease of DIC but a constant alkalinity in
the cultures aerated with air or CO2-free air, suggesting that bicarbonate utilization was concomitant with an efflux of OH−. Both alkalinity and pH were maintained rather constant in air-grown culture of low-calcifying strain ofE. huxleyi, suggesting that diffusive entry of CO2 could meet the requirement of DIC for its photosynthesis and growth. High-calcifying strain ofE. huxleyi, however, showed a pattern of decrease of alkalinity and DIC but an almost constant pH, indicating that bicarbonate was the
major form of inorganic carbon utilised by this organism and bicarbonate uptake is unlikely to be accompanied by an efflux
of OH−.
The final pH values reached byN. oculata, P. tricornutum andP. purpureum in a closed system were 10.75, 10.60 and 9.85 respectively, showing that bicarbonate utilisation is concomitant with an efflux
of OH−. While the final pH of 8.4 in high-calcifyingE. huxleyi suggests that bicarbonate utilization was not accompanied by an efflux of OH−.
Contribution No. 3557 from the Institue of Oceanology, Chinese Academy of Sciences.
This work was supported by NERC grant GRE3/7853 U. K. and partly supported by Bio-Engineering Center, SSTC 96-C01-05-01. 相似文献
13.
Retrieval of inherent optical properties of the Yellow Sea and East China Sea using a quasi-analytical algorithm 总被引：1，自引：0，他引：1
We tested and modified the quasi-analytical algorithm (QAA) using 57 groups of field data collected in the spring of 2003 in the Yellow Sea and East China Sea. The QAA performs well in deriving total absorption coefficients of typical coastal waters. The average percentage difference (APD) is in a range of 13.9%–38.5% for the total absorption coefficient (13.9% at 440 nm), and differences in particle backscattering coefficient bbp(λ) are less than 50% (in the case of the updated QAA). To obtain improved res... 相似文献
14.
Retrieval of chlorophyll a and suspended solid concentrations by hyperspectral remote sensing in Taihu Lake, China 总被引：1，自引：0，他引：1
Chlorophyll α（ch1-α） and suspended solid concentrations are two frequently used water quality parameters for monitoring a lake. Traditional measurement of ch1-α and suspended solids, requiring laborious laboratory work, which is often expensive and time consuming. Hyperspectral remote-sensing measurement provides a fast and easy tool for estimating water trophic status. In situ hyperspectral data on March 7-8, July 6-7, September 20 and December 7-8, 2004 and the corresponding water chemical data were used to regress the algorithm of water quality parameters. Results showed that the peak of water leaving radiance around 700 nm （R700） varied proportionally with ch1-α concentration, and moved to infrared when algal bloom occurred. The reflectance ratio of R702/R685 was well correlated with ch1-α when water surface in no algal bloom case and the correlation coefficient was better if absorption of phycocyanin was considered. The reflectance ratio R620/R531 was highly correlated to the concentration of suspended solids. The relationship between suspended solids and other band groups were also compared. Secchi disk depth could be calculated by non-linear correlation with suspended solids concentration. 相似文献
15.
Laboratory culture experiments showed that <100μ mol/L nitrate, amonium or mixture of amino acids promote the growth of the
red tide organismProrocentrum micans Ehrenb, but that >100μmol/L of ammonium, or mixture of glycine and glutamate was harmful to growth, and that orthophosphate
wasP. micans’ main phosphorous source in the ocean. Presence of 80μ mol/L EDTA, 0.5 to 1 μmol/L Fe3+, 1.0 to 20.0 μ mol/L Mn2+ 0.1 to 0.4 μmol/L Co2+ in the culture medium could improve the growth ofP. micans. Vitamin B1 promoted growth, but vitamin B12 and biotin did not. The estimated minimum cell quotas (q
o) for nitrogen and phosphorus being 0.74 pmole/cell and 0.045 pmole/cell show that phosphorus (more than nitrogen) limits
the growth ofP. micans in the study area.
This project was supported by the Natural Science Foundation of Zhejiang Province. 相似文献
16.
Extracts of 21 marine invertebrates belonging to Coelenterata, Mollusca, Annelida, Bryozoa,Echiura, Arthropoda, Echinodermata and Urochordata were screened for the studies on their antitumor and immune regulation activities. Antitumor activity was determined by MTT method and immune regulation activity was studied using T- and B-lymphocytes in mice spleen in vitro. It was found that the n-butanol part of Asterina pectinifera, the acetic ether part of Tubuaria marina, 95% ethanol extract of Acanthochiton rubrolineatus have a high inhibition rate of 96.7%, 63.9% and 50.5% respectively on tumor cell line HL-60 at the concentration of 0.063 mg/ml. The inhibition rate of the acetic ether part of Tubuaria marina on the tumor cell line A-549 is 65,4 % at concentration of 0.063 mg/mL. The 95% ethanol extract of Meretrix meretrix has so outstanding promoting effect on T-lymphocytes that their multiplication increases 25% when the sample concentration is only 1μg/ml. On B-lymphocytes, the 95% extract of Rapana venosa, at concentration of 100μg/ml, has a promotion percentage of 60%. On the other hand, under the condition of no cytotoxic effect, the 95% ethanol extracts of Acanthochiton rubrolineatus and Cellana toreum can reach 92% inhibition rate on T lymphocyte at concentration of 100μg/ml, while the inhibition rate on B lymphocyte of the 95% extract of Acanthochiton rubrolineatus reaches 92% at the same concentration. 相似文献
17.
When cultured under certain environmental conditions (25°C, light intensity 80 μmol/m2·s, LD 12/12, in enriched seawater medium with 7×10−4 mol/L NO3−N, 1.56×10−4 mol/L, PO4−P and supplements of other elements like Mn, Fe, I, etc.), male and female gametophytes ofU. pinnatifida kept growing vegetatively and propagated fast at average daily fresh weight increase rate of about 20%. The empirical formulaG
m=G
o·3m was established to estimate the output of vegetative gametophytes. Vigorous vegetative gametophyte cells began to form reproductive
structures (oogonium and spermatangium, when the temperature was lower than 25°C and other environmental factors were kept
optimal. The sufficient supply of gametophyte cells provided enough seeds for raisingUndaria sporelings on production scale. Controlled cross-breeding experiments using selected male and female gametophyte clones which
increase their cell number by mitosis instead of meiosis were also carried out in vitro. Juvenile sporophytes from the cross-breeding
had almost the same length and width increase rates as those of the control. The fact that vegetative gametophytes can be
purposely selected, propagated quickly, cross-bred, with the resulting sporophytes having almost the same characteristics
leads to a new way to select desiredUndaria strains for long time use without losing the desired economic characteristics.
Contribution No. 2696 from the Institute of Oceanology, Chinese Academy of Sciences.
Supported by National Natural Science Foundation of China. 相似文献
18.
A small amount of heavy metal binding protein, identified by BioRad Protein Assay, has been isolated from the adult brine
shrimp,Artemia franciscanus. This protein has an apparent molecular weight between 6000 to 9000 dalton. a UV absorption peak at 260 instead of 280 nm
like most proteins; and has high affinity towards binding with radioactive labeled109Cd. These characteristics are similar to that of metallothioneins reported for many vertebrate and invertebrate, marine and
terrestrial animals. After the brine shrimp is exposed to a small amount of Cd2+ for 24 h, a large amount of metallothionein can be isolated, showing the inducibility of this detoxifying protein in the
adultArtemia in a short period of time. 相似文献
19.
Serum immunoglobulin of the mandarin fish, Siniperca chuatsi with development of polyclonal antibody
Serum immunoglobulin from the mandarin fish, or the so-called Chinese perch,Siniperca chuatsi (Basilewsky), was successfully purified using affinity chromatography. Heavy and light chains were detected on electrophoresis
gel, with molecular weights being estimated at 72 and 29 kDa, respectively. The tetrameric IgM ofS. chuatsi was calculated to be 808 kDa. The rabbit polyclonal antisera against the purifed immunoglobulin were developed and tested
by Western blot analysis. The antisera reacted strongly with the heavy chains ofS. chuatsi immunoglobulin. Humoral immune responses of the mandarin fish can then be examined using the developed polyclonal antibody.
Project No. 30025035 supported by NSFC, State Key Laboratory of Freshwater Ecology and Biotechnology (2000FB02), and the Chinese
Academy of Sciences (KZ9511-B1-111). 相似文献
20.
Nephroselmis gaoae sp. nov. is described on the basis of light and electron microscope observations of cultured material originally collected
and isolated from seawater of Jiaozhou Bay, Qingdao, China. The periplasts on the cell body and flagella are covered by five
types of scales, two types on the flagella and three on the body. Among these, the morphology and the number of spines of
large stellate body scales differ remarkably from those of previously described species ofNephroselmis. Apart from these, the unusual fine structure of the eyespot (stigma) is very characteristic. As in the other species ofNephroselmis, the eyespot lies immediately under the two-membraned chloroplast envelope; unlike the others, however, it is not composed
of a number of osmiophilic globules, but consists of about 14 curved rod-shaped osmiophilic bodies arranged loosely and randomly.
This feature distinguishes the present new species not only from the other species ofNephroselmis but also from the other motile algal species, the eyespots structure of which had been previously described.
Contribution No. 2316 from the Institute of Oceanology, Chinese Academy of Sciences.
This paper was presented at the XIVth International Seaweed Symposium held in Brittany, France, 1992. 相似文献