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1.
ZHANG Zhicui XUEChanghu GAO Xin LI Zhaojie WANG Qi 《中国海洋大学学报(英文版)》2006,5(3):257-262
Monthly difference of the chemical composition of oyster cultured along the eastern coast of Shandong Province was analyzed. The components analyzed included glycogen, fatty acid and free amino acid (FAA). The content of glycogen was high in January and March (2.89 and 2.82 g(100 g) ^-1 on average, respectively) and low in October (2.07g(100g)^- 1 on average). The low content of neutral lipids in October reflected a relatively poor nutritional value of oyster (1.42 g( 100 g)^- 1 on average). The main fatty acids of oyster were palmitic acid (16:0), oleic acid (18: 1), eicosapentaenoic acid (EPA, 20: 5(0 3) and docosahexaenoic acid (DHA, 22:6(0 3). The major FAAs of oyster were Taurine, Glutamicacid, Glycin, Alanine, Arginine and Proline. Taurine was the most abundant FAA with its content ranging from 603 mg(100 g) ^-1 to 1 139 mg( 100 g) ^-1. The high contents of glycogen, polyunsaturated fatty acid and FAA showed that oyster cultured along the eastern coast of Shandong Province was nutritionally good in January and March. 相似文献
2.
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
3.
The aim of this study is to isolate protoplasts from Undaria pinnatifida. Protoplasts of the alga were isolated enzymatically by using alginate lyase, which was prepared by fermenting culture of
a strain Vibrio sp. 510. Monofacterial method was applied for optimizing digestion condition. The optimum condition for protoplast preparation
is enzymatic digestion at 28°C for 2h using alginate lyase at the concentration of 213.36 U (8 mL) every 0.5g fresh thalline
with NaCl 50 and at the shaking speed of 150 r min−1 during digestion. The protoplast yield can reach 2.62±0.09 million per 0.5 g fresh leave under the optimum condition. The
enzyme activity is inhibited by Ca2+ and slightly enhanced by Fe2+ and Mn2+ at concentrations of 0.05, 0.08 and 0.10 mol L−1. 相似文献
4.
WANG Qi XUE Changhu LI Zhaojie FU Xueyan XU Jie XUE Yong 《中国海洋大学学报(英文版)》2007,6(4):407-412
The changes in the contents of adenosine 5’-triphosphate (ATP) and its related breakdown compounds were investigated in the adductor muscle, mantle, gill and body trunk of oyster (Crassostrea gigas) during frozen storage at -20℃ and -30℃ and compared with that of the fresh oyster. The investigation was performed using an HPLC system. Different extents of ATP decomposi- tion were found in various tissues frozen at the two temperatures. The K, K’ and A.E.C values were calculated as the chemical fresh- ness indices. Considering the results of sensory evaluation, the A.E.C. value in body trunk at -20℃ and -30℃ could be used as the best freshness index for frozen oyster. 相似文献
5.
After a serial of UV, EMS and NTG mutagenesis, a mutant named MM of the red marine yeast strain Rhodotorula sp. hidai was obtained. The mutant MM could produce 603.93 μg g−1 of carotenoid within 5 days in the medium containing 4.0 g sucrose, 1.5 g yeast extract, 0.1 g MgSO4, and 100 mL of sea water, with pH 6.0 and at 30 °C, while only 213.18 μg g−1 of carotenoid was produced by the wild type under the same conditions. 相似文献
6.
Abundance and production ofBranchiura sowerbyi (Oligochaeta: Tubificidae) in two typical shallow lakes (Hubei, China) 总被引:1,自引:0,他引:1
An April 1996 to March 1997 comparative study on the abundance and secondary production ofBranchiura sowerbyi Beddard, 1892 in two typical shallow lakes showed that in Houhu, an algae-dominated lake, the worm density (68 ind·m−2) peaked in July, biomass (1.930 g·m−2) peaked in June, while in Biandantang, a macrophyte-dominated lake, standing stock (density: 60 ind·m−2; biomass: 1.019 g·m−2 in wet weight) peaked in December. Secondary production of the animal in Houhu Lake was 3.413 g wet wt m−2 a−1, a little more than that (2.675 g wet wt m−2 a−1) in Biandantang Lake. Their turnover rates (P/B ratios) were 4.0 and 5.0, respectively.
Project (39600019 and 39430101) supported by NSFC. 相似文献
7.
STUDY ON EMBRYONIC DEVELOPMENT AND EARLY GROWTH OF TRIPLOID AND GYNOGENETIC DIPLOID LEFI—EYED FLOUNDER, PARALICHTHYS OLIVACEUS (T. et S. ) 总被引:1,自引:0,他引:1
The early effects of chromosomal manipulation of eggs and sperm on the yields of trip-loid and gynogenefic diploid larvae of Paralichthys olivaceus were investigated. Triploidy was achieved by cold shocking fen.ilized eggs at 0 - 2℃ for 45 minutes duration 5 minutes after fen.ilization, and the in-duced triploidy rates were 31.2% - 50% and the relative hatching rates were 53.3% - 99%. Gynnge-aetic diploids were obtained when eggs were inseminated with irradiated sperm and cold shocked at 0 -2℃ for 45 minutes duration 5 minutes after fertihzation. The induced gynogenetic diploid rates and the relative hatching rates were 94 % - 96 % and 48.5 % - 68.5 % respectively. The embryonic development of the triploid experimental group and of the gynogenetic diploid experimental group was delayed at first compared with the control group. But from the gastrula stage, it was not delayed anymore. There were no significant differences in the growth of the triploid experimental group larvae and the control group larvae, and in the growth of the gynogenetic diploid experimental group larvae and the control group larvae ac-cording to Student‘s t-test (α = 0.05). The relationship between the early growth of the triploid experi-mental group larvae and that of gynogenetic diploid experimental group larvae was also studied. 相似文献
8.
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
9.
The sea fluxes of trace metals, POC, and settled material were studied in anoxic seawater, Saanich Inlet, B. C., Canada with
sediment traps. This paper discusses the change of mass fluxes of sediment, trace metals and POC for various seasons and depths.
The annual mean of settled material is 1.56 g.m−2.a−1, 84.6 mg. m−2.a−1 for POC, 60.0 mg. m−2.a−1 for Cu, 16.5 mg.m−2.a−1 for Pb, 189 mg.m−2.a−1 for Zn, 2.20 mg.m−2.a−1 for Cd, 699 mg.m−2.a−1 for Fe, 38.8 mg.m−2.a−1 for Co, and 84.6 mg.m−2.a−1 for Ni. The relations between the average fluxes of trace metals and POC, the fluxes of trace metals and settled matter,
and the sea fluxes of trace metals and Fe are in linear progression. The resident times of elements as calculated from sea
flux, are 1.1 a. for Cu, 0.014 a. for Pb, 0.50 a. for Zn, 3.8 a. for Cd, 0.16 a. for Fe, 0.39 a. for Co, and 1.14 a. for Ni.
The order of resident times is as follows: Pb−Fe−Co−Zn−Cu−Ni−Cd. The metal resident times in Saanich Inlet are shorter than
the values estimated for the open ocean. It illustrates that the biochemical processes in shallow Saanich Inlet are faster
than those in the open ocean, and that debries of plankton and fecal pellets of zooplankton play an important role in vertical
transport of organic carbons.
Contribution No. 1650 from the Institute of Oceanology, Academia Sinica. 相似文献
10.
Zhang Guo-fan Chang Ya-qing Song Jian Ding Jun Shen Jin-kai Wang Yong-ping 《中国海洋湖沼学报》1998,16(3):249-255
Zygotes of Pacific oyster (Crassostrea gigas) were treated for triploid induction with caffeine (10 mmol/L, 15mmol/L and 20mmol/L) in combination with thermal shocks
(at 40 minute post-fertilization) lasting for 5 and 10 minutes. The highest yield of triploids, 41.5%, was obtained from the
treatment with 20 mmol/L caffeine at 34°C lasting 10 minutes. The triploid levels were less than 30.0% in other treatments.
Triploid induction was more effective in treatment with 15–20 mmol/L caffeine at 34–38 °C than with lower concentrations of
caffeine at temperatures below 32 °C. Our results suggest that triploid induction with caffeine in combination with thermal
shocks is less efficient than some other methods reported previously. 相似文献
11.
Chromosome constitution was investigated in adult tetraploid Pacific oyster produced by blocking the first polar body of triploid eggs which were fertilized with haploid sperms. A high incidence of aneuploid and heteroploid mosaics were found among the offspring. Of 20 individuals identified, only 9 (45%) were eutetraploid which contained 40 chromosomes; 2 (10%) were aneuploid (hypotetraploid), which contained 39 and 38 chromosomes, respectively; and 9 (45%) were heteroploid mosaics. One mosaic was consisted of cells containing 40 and 39 chromosomes, respectiovely (1:1 in cell number), while the other 8 were consisted of cells containing chromosomes varying between tetraploid and triploid. It was also interesting to note that 3 mosaics even contained some diploid cells with 20 chromosomes. A certain number of cells of 2 tetraploids and 8 mosaics spread with 32–37 well-scattered and some clumped chromosomes at metaphase. The percentage of aneuploid cells with chromosomes varying between triploid and tetraploid correlated significantly with that of heteroploid mosaics cells with clumping chromosomes (P<0.05). Our findings suggested that reversion existed in both tetraploid and triploid oyster and chromosome clumping may underline the chromosome elimination in tetraploid oyster. It seems that the reversing cells, at least some of them, continuously eliminate their chromosomes until the most stable diploid state is established. 相似文献
12.
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
13.
Effects of salinity, pH, nitrogenous and phosphate nutrients on the growth rate of four species of benthic diatoms were studied
by using the method of in situ optical density measurement. The optimal culture conditions for the four species of diatoms
are as follows: forAmphora coffeaeformis, s 35; pH 8.5; NO3
−−N 1.54, NH4
+−N, 7.0; CO (NH2)2−N, 2.5 (mg/L); PO4
3−−P 1.13 (mg/L); forCocconeis scutellum varparva, s 30; pH 8.5; NO
3
−
−N 3.08, NH
4
+
−N 3.5, CO(NH2)2−N 5.0 (mg/L); pO
4
3−
−P 0.283 (mg/L); forNavicula corymbosa s 25; pH 8.0; NO
3
−
−N 1.54, NH
4
+
−N 3.5 CO(NH2)2−N 5.0 (mg/L); PO
4
3−
−P 0.565 (mg/L); forNavicula mollis. s 25; pH 8.0; NO
3
−
−N 1.54, NH
4
+
−N 1.75, CO(NH2)2−N 1.25 (mg/L); PO
4
3−
−P 0.141 (mg/L).
Part of the results of this paper were exchanged in the Fourth Asian Aquaculture Forum. Oct. 16–20. 1995. Beijing, P. R. China. 相似文献
14.
Effects of hypoxia on dopamine concentration and the immune response of White Shrimp (Litopenaeus vannamei) 总被引:1,自引:0,他引:1
Effects of hypoxia on the dopamine concentration and the immune response of White Shrimp Litopenaeus vannamei were studied. The results showed that hypoxia had significant effects on the concentration of dopamine (DA) in the haemolymph,
haemocyte count, phenoloxidase activity, phagocytic activity of haemocytes and bacteriolytic and antibacterial activity in
the haemolymph (P<0.05). The concentration of the dopamine in haemolymph reached its maximum in the 3.0 and 1.5 mg L−1 DO groups at 12 h and 6 h, and then returned to normal after 24 h and 12 h, respectively. All immune parameters decreased
with the reduction of dissolved oxygen. Total haemocyte count (THC), the hyaline cells and semi-granular cells in the 3.0
mg L−1 DO group became stable after 12 h, while granular cells did so after 24 h. The THC and different haemocyte count (DHC) in
the 1.5 mg L−1 DO group became stable after 24 h. Phenoloxidase activity and bacteriolytic activity in the 3.0 and 1.5 mg L−1 DO groups reached their stable levels after 24 h and 12 h respectively, while phagocytic activity and antibacterial activity
became stable after 24 and 12, and 36 and 24 h, respectively. It was also indicated that the changes of dopamine concentrations
in haemolymph, haemocyte count and phenoloxidase activity were obviously related to the exposure time under hypoxic conditions. 相似文献
15.
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
16.
Trare amounts of benzene hydrocarbons obtained in Jiaozhou Bay (Qindao) were enriched bysorption on a GDX-102 column and eluted by carbon disulfide. The eluted was concenttaled and then de-temened by capillary column gas cbornatognphy.The contents of virious kinds of benzene hydrocarbons in Jiaozhou Bay coastal water were benzene(22.3-141.6)× 10~(-9)g/L, toluate (15.2-94.0) × 10~(-9) g/L, ethyl benzene(11.8-85.1)×10~(-9) g/L, p -xylene(15.2-78.5) ×10(-9) g/L, m-xylene (10.9-79.4) ×10(-9) g/L, o -xylene (12.4-80.1) x ×10(-9)g/L; iso-propyl(8.4- 73.1) x ×10(-9)g/L, n -propyl (6.9-76.4) ×10(-9) g/L, 1, 3, 5-trimethylbenzene (10.9- 35.9)×10(-9) g/L, 1,2, 4-trimethybenzene (10.0- 38.0)×10(-9) g/L, n - butydriare (8. 1 - 34.6) ×10(-9)g/L. The recovery of benzenehydrocarbons was (85.1 -95.6)%. 相似文献
17.
The process-oriented model Forest-DNDC describing biogeochemical cycling of C and N and GHGs (greenhouse gases) fluxes (CO2, NO and N2O) in forest ecosystems was applied to simulate carbon sequestration and GHGs emissions in Abies fabric forest of the Gongga Mountains at southeastern edge of the Tibetan Plateau. The results indicated that the simulated gross primary production (GPP) of Abies fabric forest was strongly affected by temperature. The annual total GPP was 24,245.3 kg C ha^-1 yr^-1 for 2005 and 26,318.8 kg C ha^-1 yr^-1 for 2006, respectively. The annual total net primary production (NPP) was 5,935.5 and 4,882.2 kg C ha^-1 yr^-1 for 2005 and 2006, and the annual total net ecosystem production (NEP) was 4,815.4 and 3,512.8 kg C ha^-1 yr^-1 for 2005 and 2006, respectively. The simulated seasonal variation in CO2 emissions generally followed the seasonal variations in temperature and precipitation. The annual total CO2 emissions were 3,109.0 and 4,821.0 kg C ha^-1 yr^-1 for 2005 and 2006, the simulated annual total N2O emissions from forest soil were 1.47 and 1.36 kg N ha^-1 yr^-1 for 2005 and 2006, and the annual total NO emissions were 0.09 and o.12 kg N ha^-1 yr^-1 for 2005 and 2006, respectively. 相似文献
18.
Liang Yanling 《中国海洋湖沼学报》1984,2(1):102-108
Branchiura sowerbyi in the Donghu Lake (Wuhan, China) completes its life cycle in one year. Its production rates were 6.7 g m−2 yr−1 (wet weight) during the period from April 1962 to May 1963 and 8.6g m−2 yr−1 during the period from August 1963 to August 1964. The standing stocks in corresponding periods were 1.9g m−2 (wet weight) and 1.1g m−2, and theP/B ratios were 3.6 and 7.8. Based on the standing stock during 1973–1975, an evaluation of recent productin levels ofB. sowerbyi in Donghu Lake has also been made (i.e. 5.7–33.5g m−2 yr−1). 相似文献
19.
WANG Ping CHI Zhenming MA Chunling 《中国海洋大学学报(英文版)》2006,5(3):263-268
Yeast strain 10 with high yield of protease was isolated from sediments of saltern near Qingdao, China. The protease had the highest activity at pH 9.0 and 45℃. The optimal medium for the maximum alkaline protease production of strain 10 was 2.5 g soluble starch and 2.0 g NaNO3 in 100 mL seawater with initial pH6.0. The optimal cultivation conditions for the maximum protease production were temperature 24.5 ℃, aeration rate 8.0 L min^- 1 and agitation speed 150 r min^-1 . Under the optimal conditions, 623.1 Umg^-1 protein of alkaline protease was reached in the culture within 30 h of fermentation. 相似文献
20.
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