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1.
Sequence variation of partial cytochrome b genes between two Coilia species, C. ectenes and C. mystus, was investigated. Of the 402 nucleotides, twenty-seven (6.72%) are polymorphic and all are synonymous substitutions. At
the third positions of genetic condon of cytochrome b gene, the two species show an extreme anti-G bias (<4%) and a pronounced bias towards A and C (>68%). There is no amino acid
sequence divergence between the partial cytochrome b genes of the two species, indicating a close genetic relationship between them. The k-2p genetic distance of partial cytochrome
b segment of the two species is 0.072, suggesting that the species were separated 3.6 Ma ago, in the middle Pliocene. Our result
reveals that the cytochrome b gene is an appropriate marker for studies of population genetic structures and phylogeographic patterns of the two species. 相似文献
2.
Yan Xinghong 《中国海洋湖沼学报》1993,11(3):235-244
Isolated protoplasts from thalli ofPorphyra haitanensis andPorphyra yezoensis were treated with colchicine or irradiated by ultraviolet (UV). Several types of color variants were observed among the protoplast
offspring. After treatment with colchicine: (1) 0.04–0.09% of red type variants inP. haitanensis were obtained; (2) The rate of red type variants and the variegated chimeral thalli composed of red type and wild type of
sectors were 0.31–1.11% inP. yezoensis. After irradiation with UV: (1) 3.5–10.5% of red type variants inP. yezoensis were obtained: (2) 0.5–2.0% of red type variants and the variegated chimeral thalli composed of red type and wild type of
sectors were obtained inP. haitanensis. Colchicine and UV’s mutangenic effects onP. yezoensis protoplasts were stronger than those onP. haitanensis protoplasts. The most efficient concentration of colchicine was 0.05%. The optimal length of UV-radiation was 1/2 min (radiation
distance 5 cm). The red type variants induced by colchicine treatment grew faster than the wild type thalli. The clones of
vegetative propagation from protoplasts of red type variants were still red type thalli. The red type variants will be good
materials for genetic studies and improvement ofPorphyra strains. 相似文献
3.
The toxic effects of benzo[α]pyrene (B[α]P) at different concentrations (0.1, 0.5, 1, 2.5 and 7.5 μgL−1) on scallop (Chlamy farreri) immune system were studied. The results showed that B[α]P had significant toxic effects on the haemocyte counts, neutral red uptake, phagocytosis, bacteriolytic and antibacterial
activity (P<0.05), while the seawater control and acetone control had no significant differences. The haemocyte counts, neutral red uptake,
phagocytosis and bacteriolytic activity in all B[α]P treatment groups as well as antibacterial activity in groups of 0.5, 1, 2.5 and 7.5 μgL−1 B[α]P decreased significantly (P<0.05). Some of these indices tended to be stable on the sixth day and others on the ninth day, and the indices showed clear
time- and concentration-response to B[α]P. Bacteriolytic activity in 0.1μgL−1 B[α]P treatment group and antibacterial activity in 0.1 μgL−1 and 0.5 μgL- B[α]P treatment groups increased at the beginning of exposure and reached their peaks on day 1 and day 6, respectively. Following
that, both activities decreased gradually and became stable after day 9. When all the indices reached stability, they were
significantly lower than those in control group (P<0.05), except for antibacterial activity in 0.1 μgL−1 B[α]P treatment group (P>0.05). Thus, B[α] has evident toxic effects on scallop immune system, which supports the view that a relationship exists between pollution
and immunomodulation in aquatic organisms. 相似文献
4.
In this report, complete mitochondrial genome sequences of Laminaria cultivation variety ‘Rongfu’ were obtained. The results showed the length of circular molecule of mtDNA was 37 638 bp (64.7%
A+T), encoding three rRNAs (23S, 16S and 5S), 25 tRNAs, 35 known mitochondrial proteins and 3 ORFs. Sequence alignment indicated
its mtDNA genome was very similar to that of Laminaria japonica. Phylogenetic trees inferred from concatenated 30 mitochondrial genes showed that ‘Rongfu’, Laminaria japonica, Laminaria longipedalis, Laminaria diabolica, Laminaria religiosa and Laminaria ochotensis clustered together. In addition, compared with mitochondrial genome of L. japonica, ‘Rongfu’ mtDNA lacked a non-coding region of 19 nucleotides, which was located between rRNA small subunit gene 3 (rps3) and rRNA small subunit gene 9 (rps9). Seven cultivation varieties of China were divided into two groups based on this non-coding region which was absent in
‘Rongfu’, ‘Fujian’ and ‘Sanhai’ while present in ‘Ailunwan’, ‘Dongfang No.2’, ‘Dongfang No.3’ and ‘Zaohoucheng’. So this variation
can be used in germplasm identification of cultivation variety. 相似文献
5.
Four bromophenols were isolated from the extract of marine red alga,Rhodomela confervoides by column chromatography and HPLC methods. By means of spectroscopic methods inclding IR, MS, 1D, and 2D-NMR techniques,
their structures were elucidated as (1) 3-bromo-4,5-dihydroxy benzoic acid methyl ester; (2) bis (2,3-dibromo-4,5-dihydroxybenzyl)
ether; (3) 3,4-dibromo-5-(methoxymethyl)-1,2-benzenediol and (4) 3-bromo-4,5-dihydroxy-benzaldehyde. Compound 1 was first
isolated from the algae in nature, and 1, 4 were found to have selective cytotoxic activities against KB, Bel 7402 and A549
cells, 2 showed powerful antibacterial activities againstStaphylococcus aurens andPseudomonas aeruginosa.
Supported by National “863” Program (No. 2004AA625030, 2001AA620503), Quingdao marine sciences project (No. 04-2-NN-26) and
Key Knowledge Innovative Project of the Chinese Academy of Sciences (KZCX3-SW-215). 相似文献
6.
Four kinds of polysaccharides (FA, FB, FC and FD) were extracted and purified from a red alga Furcellaria lumbricalis. Their monosaccharide composition, average molecular mass
and structural feature were determined by gas chromatography (GC), high performance gel permeation chromatography (HPGPC)
and Fourier transform infrared spectroscopy (FTIR), respectively. The results showed that FA and FB were composed of galactose
(Gal), 3,6-anhydro-galactose (AnG) and 4-sulfated-galactose (G4S), which were structurally similar to β-carrageenan and κ-carrageenan.
FC was composed of sulfated galactose and small amount of AnG, indicating that it was a hybrid-sulfated galactan. FD was composed
of α-1,4-glucose and belonged to floridean starch. The respective yields of FA, FB, FC and FD were 4.84%, 33.74%, 8.76% and
13.5%, and the corresponding
were 537 kD, 432 kD, 513 kD and 51 kD respectively. Owning to its high content (>60%) of polysaccharide, F. lumbricalis will be a good source of marine sulfated polysaccharide and shows its potential utilization in food and medicine. 相似文献
7.
The ultrastructure of hemocytes ofPenaeus vannamei was examined by transmission electron microscope. Three types of hemocytes were identified: hyaline cell, small-granule cell
and large-granule cell. Hyaline cells are the smallest of the hemocytes, lack electron-dense granules, have average size of
11.11 μm (SE±0.50,n=10)×6.96μm (SE±0.55,n=10), comprise 25.8% (SE±2.87,n=4×10) of the hemocytes; small granule cells are the most abundant type of hemocytes, comprise 58.1% (SE±3.40,n=4×10) of the hemocytes, contain small electron—dense granules, have average size of 10.78 μm (SE±0.60,n=10)×8.63 μm (SE±0.44,n=10); and large-granule cells comprise 16.1% (SE±2.55,n=4×10) of the hemocytes, are filled with large electron dense granules, have average size of 12.51 μm (SE±0.63,n=10)×8.99μm (SE±0.71,n=10).
This research was supported by the National Climbing Project B, PDB6-6-3.
Contribution No. 3448 from the Institute of Oceanology, Chinese Academy of Sciences. 相似文献
8.
Effects of salinity, light and temperature on growth rates of two species of Gracilaria (Rhodophyta) 总被引:2,自引:0,他引:2
Effects of temperature, salinity and light intensity on growth rates of Gracilaria lichenoides and G. tenuistipitata var. liui Zhang et Xia were tested. Eight to ten levels of each factor were first tested separately. The best growth rate was obtained
under the conditions of 32°C, 30 and 240 μmol/(m2·s) for G. lichenoides, and 24°C, 20 and 200 μmol/(m2·s) for G. tenuistipitata, respectively. Then a uniform design was used to evaluate the optimal combinations of the three factors. The best conditions
for the highest daily specific growth rates (% increase in wet weight) are determined to be 31.30°C, 32.10, and 287.23 μmol/(m2·s) for G. lichenoides (16.26%/d), and 25.38°C, 21.10, and 229.07 μmol/(m2·s) for G. tenuistipitata (14.83%/d), respectively.
Supported by the 908 Special Program (908-02-04-07), the National Basic Research Program of China (973 Program, No. 2006CB400608),
and K. C. Wong Magna Fund in Ningbo University 相似文献
9.
A feeding trial was conducted in a recirculating water system to investigate the effects of dietary protein levels on growth,
feed utilization, hepatosomatic index and liver lipid deposition of juvenile red snapper, Lutjanus argentimaculatus (average initial wet weight 8.0 ± 0.39 g and total length 3.14 ± 0.3 cm). In the experiment, six fishmeal-based diets were
formulated to contain various protein levels (20% to 45% in 5% increments), with dietary energy ranging from 2210.7kJ lOOg
to 2250.2kJlOOg dry matter. The protein to energy ratios of diets ranged from 8.58 mg protein kJ−1 to 20.03 mg protein kJ−1. Diets were fed for 90d to triplicate groups of fish stocked in 0.128m3 seawater tanks, 25 individuals each. The daily ration of 2% wet body weight was offered to the fish thrice a day. The fish
at the end of the study had more than ten-fold (77.0g) increase in weight compared to the initial (8.0g). Fish fed diets of
40% and 45% protein produced significantly (P<0.05) higher weight gain of 77.2g and 76.5g, and specific growth rate (SGR) of 2.65% and 2.62% than those of 67.0 g and 68.3g,
and 2.49% and 2.51% of the other diets. The broken-line regression of SGR against dietary protein level yielded an optimum
dietary protein requirement of 42.6% (Y=−1.6295 + 0.1114 X
2,P<0.05). Survival remained 100% among groups. Feed conversion ratio decreased from 0.45 for fish fed 20% dietary protein to
0.35 for fish fed 45% dietary protein. Nitrogen intake increased with an increase in dietary protein, which in turn resulted
in an increase in nitrogen gain of fish whole body. Fish fed 40% and 45% protein diets showed higher (P<0.05) nitrogen gain (0.27g and 0.26g) than those (0.23g and 025g) fed all other diets. Gross energy intake (GEI) in fish
fed 45% protein was lower (600.67kJ) than that (607.97 kJ) of 40% protein diet, though the differences were not statistically
significant (P>0.05); GEI ranging from 677.31 kJ to 663.20 kJ at remaining four diets (20% to 35% protein) did not appear to differ significantly
(P>0.05). The highest energy gain of 518.33 kJ was obtained with fish fed 40% protein, resulting in the highest energy retention
efficiency of 85.26%. The hepatosomatic index of fish fed diets of 20%, 25%, 30% and 35% protein were significantly (P<0.05) higher (2.09% to 2.57%) than those (1.44% and 1.41%) of fish fed diets containing 40% and 45% protein. Liver lipid
contents decreased from 8.72% to 7.0% in fish fed dietary protein of 20% to 45% in 5% increments. Results suggest that the
diet containing 40% to 42.6% protein with a P/E ratio of 17.6 mg protein kJ−1 is required for good growth of L. argentimaculatus weighing between 8.0 g and 85.2 g under the culture conditions of the present study. 相似文献
10.
A putative tetrasporophyte-specific gene, designated as SSH466 (GenBank accession No. DQ019223), was one of the genes identified
in this work using suppression subtractive hybridization (SSH) method in Gracilaria lemaneiformis. The full length of the gene was obtained using SMART RACE strategy. Sequence analysis revealed that the gene had 1 019 nucleotides,
including an open reading frame of 498 nucleotides encoding 166 amino acid residues, 158 nucleotides of 5′ untranslated region
and 363 nucleotides of 3′ non-coding region. Protein motif and secondary structure prediction showed that there existed a
transmembrane domain with a unique β-sheet. Thus, SSH466 protein might be a cross-membrane protein. Sequence homology search
in the public GenBank databases did not reveal any significant match with SSH466. Virtual Northern blot analysis confirmed
that it was a tetrasporophyte-specific gene. 相似文献
11.
DYNAMIC CHANGES OF INORGANIC NITROGEN AND ASTAXANTI—IIN ACCUMULATION IN HAEMATOCOCCUS PLUVIALIS 总被引:1,自引:1,他引:0
This study on dynamic changes of culture color,astaxanthin and chlorophylls,inorganic N including N-NO3^-,N-NO2^- and N-NH4^ in batch culture of Haematococcus pluvialis exposed to different additive nitrate concentration showed(1)ast/chl ratio was over 0.8 for brown and red algae,but was usually less than 0.5 for green and yellow algae;(2)N-NO3^-,in general,was unstable and decreased,except for a small unexpected increase in nitrate enriched treatment groups;(3)measurable amounts of N-NO2^- and N-NH4^ were observed respectively with three change modes although no extemal nitrite and ammonia were added into the culture;(4)a non-linear correlation between ast/chl ratio(or color)changes and the levels of N-NO3^-,N-NO2^-,N-NH4^ in H.pluvialis culture;(5)up and down variation of the ast/chl ratio occurred simultaneously with a perceptible color change from yellow to brown(or red)when N-NO3^-,N-NO2^- and N-NH4^ fluctuated around 30,5,5μmol/L respectively;(6)existence of three dynamic modes of N-NO3^-,N-NO2^- and N-NH4^ changes,obviously associated with initial extemal nitrate;(7)the key level of total inorganic N concentration regulating the above physiological changes during indoor cultivation was about 50 μmol/L;and(8)0.5-10mmol/L of nitrate was theoretically conducive to cell growth in batch culture. 相似文献
12.
Phycoerythrin (PE) is one of the most important proteins involved in light capturing during photosynthesis in red algae. Its
potential biological activities had gained wide concerns. In the present study, tumor cytotoxic and hydroxyl radical assay
were preformed to detect the bioactivity of recombinant PE. Recombinant plasmids pGEX-PE and pBGL were transformed into E. coli BL21 to make two recombinant strains BEX (pGEX-PE) and BGL (pBGL). PE expressing in BEX (pGEX-PE) was validated by SDS-PAGE
and Western blotting analysis. SDS-PAGE analysis indicated that the PE-GST fusion protein was mostly inclusion bodies. Specific
expression of PE was confirmed by Western blotting analysis. The recombinant E. coli BEX (pGEX-PE) cells were collected and sonicated. The supernatants were reserved for the tumor cytotoxic experiments. The
result of tumor cytotoxic assay indicated that the supernatants containing PE had the activity of inhibiting the growth of
Hela cells and with the increase of protein concentration, the inhibiting rate increased from 37.31% to 63.26%, which showed
significant difference from the control. Hydroxyl radical scavenging effect was tested with supernatants of BEX (pGEX-PE)
and BGL (pBGL) cell lysates treated with sonication and heating. For the sonication samples, the scavenging rates of the supernatants
of BEX (pGEX-PE) and BGL (pBGL) cell lysates were significantly higher than the negative control BL21(pGEX-4T) (P<0.02), and the scavenging rates increased slowly following the increase of the protein content. For the heating samples,
except for the 0.2 mg mL−1 BGL (pBGL) products, the scavenging effects of the supernatants of BEX (pGEX-PE) and BGL (pBGL) cell lysates were stronger
than that of negative control BL21(pGEX-4T). However, the effect intensity was not positively correlated with the increase
of the protein concentration. Though a partially decreased hydroxyl radical scavenging activity was led by heating, the biological
activity was still retained and conspicuous. This research showed that phycoerythrin protein expressing in E. coli has the potential medical and sanitarian value. 相似文献
13.
To investigate the antitumor effect of bromophenol derivatives in vitro and Leathesia nana extract in vivo, six bromophenol derivatives 6-(2,3-dibromo-4,5-dihydroxybenzyl)-2,3-dibromo-4,5-dihydroxy benzyl methyl ether (1), (+)-3-(2,3-dibromo-4,5-dihydroxyphenyl)-4-bromo-5,6-dihydroxy-1,3-dihydroisobenzofuran (2), 3-bromo-4-(2,3-dibromo-4,5-dihydroxybenzyl)-5-methoxymethyl-pyrocatechol (3), 2,2′,3,3′-tetrabromo-4,4′,5,5′-tetrahydroxy-diphenylmethane (4), bis(2,3-dibromo-4,5-dihydroxybenzyl) ether (5), 2,2′,3-tribromo-3′,4,4′,5-tetrahydroxy-6′-ethyloxymethyldiphenylmethane (6) were isolated from brown alga Leathesia nana, and their cytotoxicity were tested by MTT assays in human cancer cell lines A549, BGC-823, MCF-7, B16-BL6, HT-1080, A2780,
Bel7402 and HCT-8. Their inhibitory activity against protein tyrosine kinase (PTK) with over-expression of c-kit was analyzed also by ELISA. The antitumor activity of ethanolic extraction of Leathesia nana (EELN) was evaluated on S180-bearing mice. All compounds showed very potent cytotoxicity against all of the eight cancer cell lines with IC50 below 10 μg/mL. In PTK inhibition study, all bromophenol derivatives showed moderate inhibitory activity and compounds 2,
5 and 6 showed significant bioactivity with the inhibition ratio of 77.5%, 80.1% and 71.4%, respectively. Pharmacological
studies reveal that EELN could inhibit the growth of Sarcoma 180 tumor and increase the indices of thymus and spleen to improve
the immune system remarkably in vivo. Results indicated that the bromophenol derivatives and EELN can be used as potent antitumor agents for PTK over-expression
of c-kit and considered in a new therapeutic strategy for treatment of cancer.
Supported by the National High Technology Research and Development Program of China (863 Program, No. 2007AA09Z410) and Knowledge
Innovation Program of Chinese Academy of Sciences (No. KZCX2-YW-209) 相似文献
14.
The acute toxic levels of formalin to a marine red-tide dinoflagellate Prorocentrum minimum Schiller (Mastigophora, Dinoflagellida) were determined by linear regression analysis. The data obtained revealed that there is a close regression relationship between logarithmic concentrations of formalin and mortality probit scales of the organism when exposure times are 1, 2, 6, 12, 24 h. The median lethal concentrations (LC50 values) obtained from correlation analysis for these exposure times (with 95% confidence intervals), were 11.83, 6.76, 4.37, 4.27 and 3.98mgL^-1 respectively. A toxicity curve was obtained to connect the exposure time and LC50 value from the correlation between them. The results indicated that P. minimum could be killed or fixed by formalin in the concentration range of 4-12mgL^-1 within 1-24h. 相似文献
15.
In order to reveal transpiration rates of wetland plants and its relationships to micro- meterological factors in a mountain valley wetland, relative humidity, air temperature, leaf temperature, soil temperature, photo flux density and transpiration rates were measured once two hours in a Carex meyeriana wetland of the Changbai Mountain valley in dry (July) and wet (September) of 2003, respectively. Results showed that the tendency of "decreasing after increasing" was obvious in wet season. However, a relatively stable trend was observed for the transpiration in dry season.. Generally, the photon flux density of Carex meyeriana was higher in wet season than that in dry season. However, the variabilities of leaf temperature, air temperature and relative humidity were similar in both seasons. Higher transpiration rates of Carex meyeriana leaves were observed in July (varied from 40 to 150 mol.m^-2.s^-1) compared to those (varied from 7 to 14 mol.m^-2.s^-1) in September. Transpiration rates were significantly correlated with air temperature (P〈0.01), leaf temperature (P〈0.01), and wind speed (P〈0.05), but correlationship between relative humidity and photo flux density was not significant (P〈0.05). 相似文献
16.
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
17.
In this study, we evaluated the anti-proliferative activity of phlorotannins derived from brown algae Laminaria japonica Aresch extracts on the human hepatocellular carcinoma cell (BEL-7402) and on murine leukemic cells (P388) by MTT assay. Cells
were incubated with 100 μg/mL of the phlorotannin extract (PE) for 48 h. The inhibitory rate of PE on BEL-7402 and P388 cells
was 30.20±1.16% and 43.44±1.86%, respectively, and the half-inhibitory concentration of PE (IC50) on P388 and BEL-7402 cells was 120 μg/mL and >200 μg/mL, respectively. Microscopic observation shows that the morphologic
features of tumor cells treated with PE and 5-fluorouracil are markedly different from the normal control group. The inhibitory
rate of fraction A2 isolated from PE by sephadex LH-20 for BEL-7402 and P388 cells at the sample concentration of 70.42 μg/mL was 61.96±7.02%
and 40.47±8.70%, respectively. The apoptosis peak for fraction A2 was the most profound of all fractions used in the flow cytometry assay. The results indicate that the anti-proliferative
of this algal extract is associated with the total phlorotannin content. 相似文献
18.
Prepared in this experiment were six groups of diets, i.e. VC0, VC1, VC2, VC3, VC4 and VC5 with the contents of vitamin C (VCmg(100 g)−1 diet) of 0, 100, 200, 400, 800, and 1200 respectively. It was found that vitamin C increased the concentrations of immunoglobulin-like
(IgG-like, IgA-like and IgM-like) substances in the serum of Penaeus chinensis after a feeding period of 3 weeks. The differences among groups were significant (P<0.01), but there was no difference in the contents of complement3-like and complement4-like substances in the serum (P>0.05). Phenoloxidase (PO) activity in the serum of VC3 group shrimps was higher than that of VC0 and other groups, but no
significant difference was observed between VC0 group and other groups. Furthermore, bactericidal activity of the serum to
Vibrio parahaemolyticus in shrimps fed with the VC1 diet was higher than that in the other groups (P<0.01), while no difference was demonstrated among all groups for the bactericidal activity to Vibrio alginolyticus (P>0.05). It is, therefore, suggested that vitamin C (100–400 mg(100 g)−1 diets) could be used as an immunostimulant of P. chinensis. 相似文献
19.
Sodium thiosulphate and neutron activation determination of iodine content in samples of 18Sargassum species collected in Guangdong and Guangxi Province in April 1996 showed large differences (0.47×10−3 inSargassum hemiphyllum, 0.56×10−3 inSargassum assimile, and 4.5×10−3 inSargassum vachellianum). Traditional titration analysis and neutron activation analysis for determination of total iodine yielded similar results
showing that certainSargassum species had high capacity to accumulate iodine.
Contribution No. 3162 from the Institute of Oceanology, Chinese Academy of Sciences.
The project was supported by the National Ninth Five-Year Plan of China (No. 96-916-04-01). 相似文献
20.
This study deals with contribution of artificial food pellet and natural food to Chinese prawn (Penaeus orientalis) growth in a semiintensive culture pond. The prawn carbon consumption, budget, and the effects of some factors on the budget were investigated. The results showed that 26.2% of P. orientalis growth carbon came from formulated feed at the initial culture stage (when the prawns were 0.06±0.01 g in wet weight), and was 62.5% when the prawns were 9.56±1.04 g. The remaining part of the growth carbon was derived from organic fertilizer and natural food. The highest growth rate occurred at 20×10-3 salinity. Suitable salinity for culturing Chinese prawn was (20-28)×10-3. 相似文献