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1.
KANG Kyoung Ho 《中国海洋大学学报(英文版)》2009,8(3):265-269
Trumpet shell, Charonia sauliae, is an endangered and valuable species, but its artificial propagation protocol has not been successfully established. To
estimate the possibility of cryopreservation for larvae of C. sauliae, which is a potential preparation for its artificial reproduction and further research, in this study a protocol for the
cryopreservation of veliger larvae of trumpet shell was optimized. Through a two-step cryopreservation procedure, four kinds
of cryoprotectants (ethylene glycol, 1, 2-propanediol, dimethyl sulfoxide and glycerol) were employed at three concentrations
(1.0, 1.5 and 2.0 molL−1) respectively and survival rates of larvae were determined after a storage of 1h. The larvae frozen with these four cryoprotectants
after 1 h storage were cultured, and then survival rates were determined at 24, 72 and 120 h after thawing. Dimethyl sulfoxide
at a concentration of 1.5 molL−1 showed the best protective effect in all experiments (p<0.05). And survival rates of larvae frozen with dimethyl sulfoxide were determined after 1, 7 and 15 d of storage. The survival
rates of larvae frozen with 1.5 molL−1 dimethyl sulfoxide after 1 h, 1 d, 7 d and 15 d of storage were 80.77% ±7.51%, 80.34% ±11.28%, 83.10% ±9.14% and 77.23% ±6.22%
respectively. No significant differences in survival rates of larvae frozen with dimethyl sulfoxide were observed after various
storage periods (p>0.05). 相似文献
2.
Gametophytes of Laminaria japonica were cryopreserved in liquid nitrogen using encapsulation-dehydration with two-step cooling method. Gametophytes cultured at 10℃ and under continuous irradiance of 30 μmol m-2 s-1 for 3 weeks were encapsulated in calcium alginate beads. The beads were dehydrated in 0.4 molL-1 sucrose prepared with seawater for 6 h, desiccated in an incubator set at 10℃ and 70% relative humidity for 4 h, pre-frozen at either -40℃ or -60℃ for 30 min, and stored in liquid nitrogen for ＞24 h. As high as 43% of survival rate was observed when gametophytes were thawed by placing the beads in 40℃seawater and re-hydrated in 0.05 molL-1 citrate sodium prepared using 30‰ NaC1 7 d later. More cells of male gametophytes survived the whole procedure in comparison with female gametophytes. The cells of gametophytes surviving the preservation were able to grow asexually and produce morphologically normal sporophytes. 相似文献
3.
1 INTRODUCTION Chironomid larvae are main groups in most aquatic ecosystems, playing a crucial ecological role in decomposition of detritus and material ex- changes between water column and the sediment (Liang et al., 1995a, b; Chen, et al., 1982). They a… 相似文献
4.
Chondrus is a type of commercially produced red seaweed that widely used for food and carrageen extraction. Although the natural life
history of the alga had been well understood, the factors influencing development of the tetraspore and carpospore remain
poorly understood. In the perspective of seedling resources, the regulation of early development is crucial for the seedling
nursing; therefore, it is necessary to understand the physiological influences during its early development. In this study,
we studied the effects of temperature and irradiance on the early development of Chondrus ocellatus Holm under laboratory conditions. The released tetraspores and carpospores were cultivated at different temperatures (10–28°C)
and irradiances (10, 60 μmol photons m−2s−1) with a photoperiod of 12L:12D. The results indicate that both tetraspores and carpospores are tolerant to temperatures of
10–25°C, and have the highest relative growth rate at 20°C. Irradiance variances influenced the growth of the discoid crusts,
and the influence was more significant with increasing temperature; 60 μmol photons m−2s−1 was more suitable than 10 μmol photons m−2s−1. The optimum temperature and irradiance for the development of seedlings was 20°C and 60 μmol photons m−2s−1, respectively. 相似文献
5.
Electroporation, PEC, PEG plus electroporation and Biolistics methods were tested in gene transformation ofP. yezoensis. The exogenousgus was from plasmid of pBI121 and pCAMBIA1301, both contain the CaMV35S promoter. The receptors included the protoplasts, tissues and free-living conchocelis filaments ofP. yezoensis. Several factors, for example, the voltage, capacitance and bivalent cations, etc., were studied. Results show that these four methods are all efficient for gene transformation inP. yezoensis; and that PEG is the best one, with transformation efficiency of up to 4×10−5. GUS activity was detected 26 days after transformation by using PEG method.
相似文献6.
Free-living conchocelis ofPorphyra yezoensis Ueda (Bangiales, Rhodophyta) were treated with60Co-γ rays of different doses (ranging from 100 Gy to 1000 Gy) to induce mutation. Most of the conchocelis maintained the capability
of penetrating into shells, growing and forming colonies in shells, but their vitality was seriously impaired by the irradiation
of γ-rays. A few conchocelis pigments were mutagenized directly into different color pigment mutants whose progeny-conchospores
and foliose thalli had the same colors. However, some irradiated conchocelis did not show the change in color at the conchocelis
stage. The pigment mutation could be observed only after the conchospores of these conchocelis had germinated into young foliose
thalli. Irradiation of low dose (100 Gy) promoted the growth of thallus and many with altered morphology were observed. Conchospores
of the irradiated conchocelis attached to the culture nets were cultured in the sea, and growth of these progenies was observed
and measured. 相似文献
7.
A cruise was undertaken from 3rd to 8th November 2004 in Changjiang （Yangtze） River Estuary and its adjacent waters to investigate the spatial biomass distribution and size composition of phytoplankton. Chlorophyll-a （Chl-a） concentration ranged 0.42-1.17 μg L^-1 and 0.41-10.43 μg L^-1 inside and outside the river mouth, with the mean value 0.73 μg L^-1 and 1.86 μg L^-1, respectively. Compared with the Chl-a concentration in summer of 2004, the mean value was much lower inside, and a little higher outside the river mouth. The maximal Chl-a was 10.43 μg L^-1 at station 18 （122.67°E, 31.25°N）, and the region of high Chl-a concentration was observed in the central survey area between 122.5°E and 123.0°E. In the stations located east of 122.5°E, Chl-a concentration was generally high in the upper layers above 5 m due to water stratification. In the survey area, the average Chl-a in sizes of 〉20 μm and 〈20 μm was 0.28 μg L^-1 and 1.40 μg L^-1, respectively. High Chl-a concentration of 〈20 μm size-fraction indicated that the nanophytoplankton and picophytoplankton contributed the most to the biomass of phytoplankton. Skeletonema costatum, Prorocentrum micans and Scrippsiella trochoidea were the dominant species in surface water. The spatial distribution of cell abundance of phytoplankton was patchy and did not agree well with that of Chl-a, as the cell abundance could not distinguish the differences in shape and size of phytoplankton cells. Nitrate and silicate behaved conservatively, but the former could probably be the limitation factor to algal biomass at offshore stations. The distribution of phosphate scattered considerably, and its relation to the phytoplankton biomass was complicated. 相似文献
8.
Effects of water temperature （17, 21, 25, 30 and 35℃） and body size （14.75-281.41 g initial body weight） on food consumption, growth, feed conversion, and dry matter content in orange-spotted grouper fed to satiation were investigated. The combined effect of temperature （T, ℃） and body weight （W, g） on maximum food consumption （Cmax, g/day） was described as： InCmax=-7.411＋0.828 InW＋0.317T4）.004 7T2, and the optimum feeding temperature was 33.9℃. The combined effect of temperature and body weight on growth （G） was described as： lnG=-4.461-0.2081nW＋0.394T-0.006 3T^2. The optimum growth temperature was 31.4℃, whereas overall growth rates were high at 25, 30 and 35 ℃. Feed conversion efficiencies （FCE, %）, increasing first and then decreasing with increasing temperature, averaged from 1.8 to 2.1 in terms of dry weight of food fish. The optimum temperature for FCE tended to be lower than that for growth or feeding. Dry matter content increased with both increasing water temperature （17, 25, 30 and 35℃） and body weight, and the combined effect of temperature and body weight on dry matter content （DM, %） was described as： lnDM =3.232＋0.01 4 lnW-0.004 4T＋0.001 2TInW. 相似文献
9.
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
10.
The rates of photosynthesis and respiration ofPorphyra, Laminaria andUndaria were determined with an oxygenmeter at different temperatures in an enclosed continuous-flow system. The temperature coefficients
of respiration and the net primary productivities for the three species were calculated. The spectacular rates of primary
production were found to be as high as 270 g C m−2 forP. yezoensis, 2200 g C m−2 forL. japonica and 160 g C m−2 forU. pinnatifida annually. The low respiratory rates of these three species as well as low light compensation points especially at low temperatures
are considered as a reason to save heat energy, resulting in a high productivity, especially in case ofLaminaria.
Contribution No. 945 from the Institute of Oceanology, Academia Sinica.
The paper was presented at the International Phycological Society Meeting, 19–22 Aug. 1980, Glasgow, UK. 相似文献
11.
A great quartity of cosmic dust(spherules) was found in deep-sea sediments during May to July,1983manganese nodule investigations by the R/V“XIANGYANGHONG 16”in the area 7°-11°N,167°-178°Win the Pacific.Comprehensive study of the cosmic dust and determination with Laser Raman MolecularMicroprobe(LRMM) of the molecules in it showed that besides Fe-Fe,Fe~(3+)-O,Fe-Ni,Al-O,Fe-Obr-Si and Si-Onb,it also contained the organic molecules C-H-O and C-H-S-O,various no fixed form molecules of C,CH_2,CH_3 and volatile molecules CO_2,H_2O,OH~- and H_2S,etc…The study result has very important applications for exploring the origin of interplanetary dust parti-cles and life material. 相似文献
12.
The effects of temperature, light intensity, salinity, and initial pH on the growth and fatty acid composition of Pinguiococcus pyrenoidosus 2078 were studied for eicosapentaenoic acid (EPA) production potential. The fatty acid composition was assayed by gas chromatography-mass spectrometry, which indicated that the main fatty acids were C14:0, C16:0 and EPA. The highest EPA percentage 20.83% of total fatty acids was obtained at 20℃ with the temperature being set at 20, 24, and 28℃. Under different salinities and light intensities, the highest percentages of total polyunsaturated fatty acids (PUFAs) and EPA were 17.82% and 31.37% of total fatty acids, respectively, which were achieved at salinity 30 and 100μmol photon m-2s-1 illumination. The highest percentages of total PUFAs and EPA were 38.75% and 23.13% of total fatty acids, respectively, which were reached at an initial pH of 6 with the test range being from 5.0 to 9.0. 相似文献
13.
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
14.
Costaria costata (C. Agardh) Saunders is one of common kelps distributed in many coastal areas worldwide; however, in China, no reports have
been made on cultivation of the genus. To investigate potential cultivation of the species in the northern part of China,
trials on isolation and preservation of the gametophytes were conducted using C. costata from Korea; growth and development of the gametophytes were observed. We showed that at 10±1°C, 60 μmol m−2s−1 and 12:12 h (L:D), freshly released zoospores settled down within 1 hour, and then developed into the primary cell during
the following 2 days. After a vegetative growth phase lasting 6–8 days, female gametophytes became 3–4 times larger in diameter
than that of the primary cell, but still remained at a unicellular stage, while male gametophytes divided into 4–10 cells
with only a slight change in size. Fertilization occurred within 10 days after the zoospores were released from the sporangia,
and the apical and basal tissues of the juvenile sporophyte divided and differentiated into the blade and stipe. Temperature
and irradiance influenced gametophytic vegetative growth and developmental patterns. Generally, low irradiance (15 μmol m−2s−1 and 30 μmol m−2s−1) was unfavorable to the induction of fertility, but it enhanced female gametophyte division. The optimal conditions for vegetative
growth were 15°C and 30 μmol m−2s−1. After transplantation of the juvenile seedlings and after eight months cultivation, the harvested mature blade reached 194
cm in length and 32.7 cm in width. Our study proves that it is feasible to implement propagation and large scale cultivation
of C. costata in northern China. 相似文献
15.
Oxygen uptake under starvation and short periods of sudden temperature change was measured for larval herring (Clupea harengus L.) reared at average temperature of 7.3, 11 and 12.9°C. Larval stages between first feeding and premetamorphosis were used.
For comparison, the routine oxygen uptake (ROU) was also investigated and followed the relationshipQ=0.974+0.174tW
−0.210, whereQ is in μg/(mg·h),W is dry body weight in mg andt is temperature in °C. The oxygen uptake under starvation (SOU, deprived of food for 24 h) was different from the routine
when the larval dry weight was less than 0.6–0.8 mg; it increased with temperature and body weight giving the relationshipQ=1.568+0.110tW
0.380; if the larval dry weight was more than 0.6–0.8 mg, it reverted to the norm (Q=1.704+0.078tW
−0.349). The oxygen uptake was tested in short periods (3 h) of sudden temperature changes in six groups: 7.3 to 11, 7.3 to 12.9,
11 to 7.3, 11 to 12.9, 12.9 to 7.3 and 1.29 to 11°C. The oxygen uptake in the 7.3 to 12.9 and 12.9 to 7.3°C groups varied
in a way similar to that of the larvae under starvation. The other four groups' oxygen uptake were more or less normal. 相似文献
16.
The International Eq一lation of State of Seawater,1980 and the PraeticalSalinity Scale,1978 have been adoPted by theUNESCO江CES沼COR八APSOJoint Panel ono‘eanogral,hie Tables and Standards(JPOTS),and endorsed bythese organizati6ns(Miller‘〕and Poisson,1981;Uneseo,1981).Th已new equa-tion and the Praetieal Salinity Seale are to be used for all values Published fromJan .1,1982 .The new equation 15 aeeurate for use in all oeeanie surfaee waters,but eannot be aeeurately aPPlied to… 相似文献
17.
ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｍｅｔａｂｏｌｉｓｍｉｎｆｉｓｈｉｎｃｌｕｄｅｓｓｔａｎｄａｒｄｍｅｔａｂｏｌｉｓｍ(ＲＳ)ｒｏｕｔｉｎｅｍｅｔａｂｏｌｉｓｍ(ＲＲ),ｓｐｅｃｉｆｉｃｄｙｎａｍｉｃａｃｔｉｏｎ(ＳＤＡ)ａｎｄａｃｔｉｖｅｍｅｔａｂｏｌｉｓｍ(ＲＡ),ｒｅｌａｔｅｄａｓ: ＲＴ=ＲＳ ＲＲ ＳＤＡ ＲＡｗｈｅｒｅＲＳｉｓｔｈｅｍｅｔａｂｏｌｉｓｍｏｆｔｈｅｆｉｓｈａｔｒｅｓｔ;ＲＲｔｈｅｍｅｔａｂｏｌｉｓｍｏｆｔｈｅｒｏｕｔｉｎｅｌｙａｃｔｉｖｅｆｉｓｈ;ＳＤＡｔｈｅｍｅｔａｂｏｌｉｓｍｏｆｔｈ… 相似文献
18.
Sand wedge is formed under the conditions of coldclimate, and is an important basis for reconstructingpaleoenvironment (LI et al., 1990; WANG, 1991 ). Ithas been reported constantly over the last 20 years inthe Qinghai-Xizang (Tibet) Plateau (GUO, 1979; CUl,1983; XU et al., 1984; LIANG et al.,, 1984; PAN etal., 199 ) and North China (YANG et al., 1983; DONGet al., 1985) and Northeast China (GUO et al.,1981 ). We also found fossil sand wedge groups formedin the end of the Late P… 相似文献
19.
The marine yeast strain N13d, producing an extracellular amylase, was isolated from the deep sea sediments of the Pacific
Ocean. This strain was identified to be Aureobasidium pullulans by 18S rRNA gene sequence analysis and routine yeast identification methods. The optimal sea water medium for amylase production
by this yeast strain was 1.0% peptone and 1.0% soluble starch with pH 4.0. The optimal conditions for amylase production by
this yeast strain were with temperature 28 °C, aeration rate 6 Lmin−1 and agitation speed 250 rmin−1. Under these conditions, 58.5 units of amylase activity per mg protein were produced within 56 h of fermentation. 相似文献
20.
A new pullulan-producing yeast and medium optimization for its exopolysaccharide production 总被引：3，自引：2，他引：1
ZHAO Shuangzhi ) CHI Zhenming ) ) * ) College of Marine Life Sciences Ocean University of China Qingdao P..R.China) The State Key Laboratory of Microbial Technology Shandong University Jinan P..R.China 《中国海洋大学学报(英文版)》2003,2(1):53-57
1 Introduction Pullulanstandsforthewater solublehomopolysac charideproducedextracellularlybythe polymorphicmicromyceteAureobasidium pullulans (Yuenetal.,1974 ;Marketal.,1988) .Itisalinearα D glucan ,mademainlyofmaltotrioserepeatingunitsintercon nectedbyα 1,6 linkages.Theregularalternationofα 1,4andα 1,6bondsresultsintwodistinctiveprop ertiesofstructuralflexibilityandenhancedsolubility(Sanjeevetal.,2 0 0 1) .Thispolysaccharideisofeco nomicimportancewithincreasingapplicationinfood ,phar… 相似文献