Effects of dietary supplementation with algal astaxanthin on growth,pigmentation, and antioxidant capacity of the blood parrot ( Cichlasoma citrinellum × Cichlasoma synspilum )

Journal of Oceanology and Limnology - An algal astaxanthin feeding trial was carried out to investigate the effects of natural astaxanthin from Haematococcus pluvialis as feed additives on growth,...     

DYNAMIC CHANGES OF INORGANIC NITROGEN AND ASTAXANTHIN ACCUMULATION IN HAEMATOCOCCUS PLUVIALIS

ＩＮＴＲＯＤＵＣＴＩＯＮＯｖｅｒｔｈｅｐａｓｔｄｅｃａｄｅ ,Ｈａｅｍａｔｏｃｏｃｃｕｓｐｌｕｖｉａｌｉｓｈａｓｂｅｅｎａｓｕｂｊｅｃｔｏｆｎｕｍｅｒｏｕｓｉｎｖｅｓｔｉｇａｔｉｏｎｓｂｅ ｃａｕｓｅｉｔｓｃｏｎｓｐｉｃｕｏｕｓｒｅｄｃｏｌｏｒｐｏｉｎｔｓｔｏｉｔｓｐｏｓｓｉｂｉｌｉｔｙａｓａｈｏｐｅｆｕｌｒｅｇｅｎｅｒａｔｉｖｅｂｉｏｒｅｓｏｕｒｃｅｏｆａｓｔａｘａｎ ｔｈｉｎ .Ｅｘｔｅｎｓｉｖｅｓｔｕｄｙｏｆｃｕｌｔｕｒｅｆａｃｔｏｒｓ (ｓｕｃｈａｓｔｅｍｐｅｒａｔｕｒｅ,ｉｌｌｕｍｉｎａｔｉｏ…     

Effects of iron electrovalence and species on growth and astaxanthin production of Haematococcus pluvialis

To increase the cell concentration and the accumulation of astaxanthin in the cultivation of Haematococcus pluvialis, effects of different iron eleetrovalencies (Fe2+-EDTA and Fe3+-EDTA) and species (Fe-EDTA, Fe(OH)32x and FeC6H5O7) addition on cell growth and accumulation of astaxanthin were studied. Results show that different iron electrovalencies have various effects on cell growth and astaxanthin accumulation of H. pluvialis. Compared with Fe3+-EDTA, Fe2+-EDTA stimulate more effectively the formation of astaxanthin. The maximum astaxanthin content (30.70 mg/g biomass cell)was obtained under conditions of 18 μmol/L Fe2+-EDTA, despite the lower cell density (2.3x105 cell/ml)in such condition. Fe3+-EDTA is more effective than Fe2+-EDTA in improving the cell growth. Especially,the maximal steady-state cell density, 2.9x105 cell/ml was obtained at 18 μmol/L Fe3+-EDTA addition. On the other hand, all the various species of iron (EDTA-Fe, Fe(OH)32x, FeC6H5O7) are capable to improve the growth of the algae and astaxanthin production. Among the three iron species, FeC6H5O7 performed the best. Under the condition of a higher concentration (36 μmol/L) of FEC6H5O7, the cell density and astaxanthin production is 2 and 7 times higher than those of iron-limited group, respectively. The present study demonstrates that the effects of the stimulation with different iron species increased in the order of FeC6H5O7, Fe(OH)32x/x and EDTA-Fe.     

Cell cycles and proliferation patterns in Haematococcus pluvialis

Most studies on Haematococcus pluvialis have been focused on cell growth and astaxanthin accumulation;far less attention has been paid to cell cycles and proliferation patterns.The purpose of this study was to clarify cell cycles and proliferation patterns in H.pluvialis microscopically using a camera and video recorder system.The complicated life history of H.pluvial i s can be divided into two stages:the motile stage and the non-motile stage.All the cells can be classifi ed into forms as follows:motile cell,nonmotile cell,zoospore and aplanospore.The main cell proliferation,both in the motile phase and non-motile phase in H.pluvialis,is by asexual reproduction.Under normal growth conditions,a motile cell usually produces two,sometimes four,and exceptionally eight zoospores.Under unfavorable conditions,the motile cell loses its fl agella and transforms into a non-motile cell,and the non-motile cell usually produces 2,4 or 8 aplanospores,and occasionally 20–32 aplanospores,which further develop into non-motile cells.Under suitable conditions,the non-motile cell is also able to release zoospores.The larger non-motile cells produce more than 16 zoospores,and the smaller ones produce 4 or 8 zoospores.Vegetative reproduction is by direct cell division in the motile phase and by occasional cell budding in the non-motile phase.There is,as yet,no convincing direct evidence for sexual reproduction.     

Study of light signal receptor of Stephanopyxis palmeriana during sexual reproduction

We collected centric diatom Stephanopyxis palmeriana samples in coastal waters of Xiamen for characteristic red light/far red light (R/FR) phytochrome reactions to identify its photoreceptor in the course of sexual reproduction. The result showed that pre-illumination of 2-3h red light before darkness could induce sexualization of S.palmeriana, while the follow-up illumination of far red light could reverse the effect of red light, which is a featured reaction of phytochrome. The Southern Dot Blot was carried out to identify the type of phytochrome that induces the sexualization. The result also showed high homogeneity of DNA fragment of S. palmeriana with phyB, but phyA. This means the photoreceptor in the process of sexual reproduction of S. palmeriana is phytochrome B (phyB).     

CHANGING FEATURES AND TREND OF LIGHT INDUSTRY DISTRIBUTION IN NORTHEAST CHINA

Modern industry in northeast China started from light industry. From the end of 19th century to 1931 was the phase of initial development of light industry in northeast China. During this period, the development of light industry gave priority to grain processing industry. After occupying northeast China, Japanese vigorously developed heavy industry to meet the needs of munitions and paid more attention to raw materials and semi-finished articles industry for the purpose of the war. Light industry was impeded and developed slowly. After the founding of New China, large-scale economic construction took place in northeast and heavy industry received prior investment and equipment. Northeast region became the first heavy industry base through several five-year plans, the development of light industry made giant strides. The present features of light industry distribution are: difference of light industry distribution, similarity of light industry structure, and imbalance of light industry development. The     

Behavioral and physiological photoresponses to light intensity by intertidal microphytobenthos

Behavioral and physiological responses to light are the two major mechanisms by which natural microphytobenthic assemblages adapt to the intertidal environment and protect themselves from light stress. The present study investigated these photoresponses with diff erent light intensities over 8 h of illumination, and used a specific inhibitor(Latrunculin A, Lat A) for migration to compare migratory and non-migratory microphytobenthos(MPB). Photosynthetic activity was detected using rapid light curves and induction curves by chlorophyll fluorescence. It showed distinct variation in migratory responses to diff erent light intensities; high light induced downward migration to avoid photoinhibition, and low and medium light(50–250 μmol/(m~2 ·s)) promoted upward migration followed by downward migration after certain period of light exposure. No significant difference in non-photochemical quenching(NPQ) or PSII maximal quantum yield(F v/F m) was detected between low and medium light irradiance, possibly indicating that only high light influences the photosynthetic capability of MPB. Decreased photosynthetic activity, indicated by three parameters, the maximum relative electron transport rate(r ETR_(max)), minimum saturating irradiance(E _k) and light utilization coefficient(α), was observed in MPB after exposure to prolonged illumination under low and medium light. Lat A ef fectively inhibited the migration of MPB in all light treatments and induced lower F v/F _m under high light(500 and 100 μmol/(m~2 ·s)) and prolonged illumination at 250 μmol/(m~2 ·s), but did not significantly influence F _v/F m under low light(0–100 μmol/(m~2 ·s)) or NPQ. The increase of NPQ in Lat A treatments with time implied that the MPB assemblages can recover their physiological photoprotection capacity to adapt to light stress. Non-migratory MPB exhibited lower light use efficiency(lower α) and lower maximum photosynthetic capacity(lower r ETR_(max)) than migratory MPB under light intensities above 250 μmol/(m ~2 ·s) after 4.0 h illumination.     

氧化亚铜可见光催化降解罗丹明B的初步研究

以Cu2O粒子为光催化剂，太阳光为光源，研究了Cu2O粒子对可溶性染料罗丹明B的光催化降解情况。并考察了不同光源，光照时间，催化剂用量，双氧水加入量和溶液的酸度等对罗丹明B光催化降解过程的影响。结果表明，Cu2O粒子在太阳光照射下，能较好地降解罗丹明B，其最佳反应条件为：罗丹明B浓度为5mg／L，催化剂（Cu2O）为0．75g／L，pH值为5．2，H2O2加入量1．0％，反应时间25min。此条件下，罗丹明B的降解率达到100％，即与在500W高压汞灯紫外（λ=365nm）光照有相同的降解效果。     

Radiation of lamp and optimized experiment using artificial light in the Arctic Ocean

A winter optical experiment by an artificial lamp was conducted in the Amundsen Bay of Arctic Ocean from November of 2007 to January of 2008.The radiation field emitted from an artificial lamp was measured and is introduced in this paper ,and the optimized experiment project is discussed.It is demonstrated that the minimum size allowed of the lamp is determined by both the field of view(FOV) of optical instrument and the measuring distance from the lamp.Some problems that might influence on the experimen...     

减氧空气与轻质原油低温氧化反应特征

塔河北区块轻质原油与减氧空气在温度和压力作用下,探究其组分变化情况和耗氧量规律。在室内使用高温高压反应釜开展原油静态氧化实验,较为系统地研究不同含氧量及不同注气量的减氧空气对原油的氧化作用;并利用色谱分析对烃类分析,收集反应气体进行气体分析,气体组分和原油组分都有不同程度的变化。研究结果表明：(1)原油样本与减氧空气发生低温氧化反应,重质组分C₂₁以上的组分均下降,低于C₁₃的轻质组分含量均上升;(2)原油氧化效果随着含氧量上升而增强,反应过程组分对应“拐点”靠前;(3)含氧量一定时,改变油气比,反应对应的“拐点”不变;含氧量为下降趋势后趋于平缓;(4)低温氧化过程生成的CO₂含量为上升趋势后趋于平缓;(5)在油藏温度(160℃)下,原油主要涉及2个反应热裂解和加氧反应。热裂解反应与含氧量无关,和温度有关,主要反应温度是160～200℃。高碳组分沥青质等重质组分会分解成饱和烃。加氧反应主要是芳香烃,胶质加氧反应也会生成沥青质。当2种反应同时存在时,沥青质参与热裂解的含量大于加氧反应芳香烃等生成的沥青质量,会导致沥青质含量...     

Study of light signal receptor of Stephanopyxis palmeriana during sexual reproduction

We collected centric diatomStephanopyxis palmeriana samples in coastal waters of Xiamen for characteristic red light/far red light (R/FR) phytochrome reactions to identify its photoreceptor in the course of sexual reproduction. The result showed that pre-illumination of 2–3h red light before darkness could induce sexualization ofS. palmeriana, while the follow-up illumination of far red light could reverse the effect of red light, which is a featured reaction of phytochrome. The Southern Dot Blot was carried out to identify the type of phytochrome that induces the sexualization. The result also showed high homogeneity of DNA fragment ofS. palmeriana with phyB, but phyA. This means the photoreceptor in the process of sexual reproduction ofS. palmeriana is phytochrome B (phyB). Supported by National Natural Science Foundation of China (No. 39670076)     

Response of cyanobacterial carbon concentrating system to light intensity: a simulated analysis

Cyanobacteria possess a delicate system known as the carbon concentrating mechanism (CCM), which can efficiently elevate the intracellular inorganic carbon (Ci) concentration via active transportation. The system requires energy supplied by photosystems; therefore, the activity of the Ci transporter is closely related to light intensity. However, the relationship between CCM and light intensity has rarely been evaluated. Here, we present an improved quantitative model of CCM in which light is incorporated, and developed a CCM model that modified after Fridlyand et a1. in 1996. Some equations used in this model were inducted to describe the relationship between transport capacity and light intensity, by which the response of the CCM to light change is simulated. Our results indicate that the efficiency of the carbon concentrating system is sensitive to light intensity. When the external Ci concentration was low, CO₂ uptake dominated the total Ci uptake with increasing light intensity, while under high external Ci concentrations HCO₃⁻ uptake primarily contributed to the total Ci uptake. Variations in the ratio of energy allocated between the transport systems could markedly affect the operation of CCM. Indeed, our simulations suggest that various combinations of Ci fluxes can provide a possible approach to detect the way by which the cell distributes energy produced by the photosystems to the two active Ci transport processes. The proportion of the energy consumed on CCM to the total energy expenditure for the fixation of one CO₂ molecule was determined at 18%–40%.     

Removal of phenol by Isochrysis galbana in seawater under varying temperature and light intensity

Phenol is a common industrial chemical produced and transported worldwide largely. Therefore, accidental spillage of phenol in the ocean causes an increasing concern. Microalgae are promising to remove phenol from marine waters. However, temperature and light intensity are two main factors that markedly influence biodegradation in marine environments. In this study, a marine golden alga Isochrysis galbana is selected to research the removal of phenol under different temperatures (10–30°C) and light intensities (0–240 µmol/(m2·s)). The results show that the most suitable temperature and light intensity for phenol removal are 20°C and 180 µmol/(m2·s), respectively, and 100 mg/L of phenol can be completely removed by microalga in 24 h at these conditions. I. galbana can also remove phenol under dark and low-temperature conditions. The removal of phenol by I. galbana at diverse temperatures and light intensities conform to first-order kinetics, and the process under dark conditions conform to zero-order kinetics. Thus, I. galbana can be used in the in-situ bioremediation of polluted seawater by phenol.     

Transcriptome analysis of carotenoid biosynthesis in Dunaliella salina under red and blue light

Journal of Oceanology and Limnology - The quality of light is an important abiotic factor that aff ects the growth and development of photosynthetic organisms. In this study, we exposed the...     

Response of cyanobacterial carbon concentrating system to light intensity: a simulated analysis

Cyanobacteria possess a delicate system known as the carbon concentrating mechanism (CCM), which can efficiently elevate the intracellular inorganic carbon (Ci) concentration via active transportation. The system requires energy supplied by photosystems; therefore, the activity of the Ci transporter is closely related to light intensity. However, the relationship between CCM and light intensity has rarely been evaluated. Here, we present an improved quantitative model of CCM in which light is incorporated, and developed a CCM model that modified after Fridlyand et a1. in 1996. Some equations used in this model were inducted to describe the relationship between transport capacity and light intensity, by which the response of the CCM to light change is simulated. Our results indicate that the efficiency of the carbon concentrating system is sensitive to light intensity. When the external Ci concentration was low, CO2 uptake dominated the total Ci uptake with increasing light intensity, while under high external Ci concentrations HCOˉ3 uptake primarily contributed to the total Ci uptake. Variations in the ratio of energy allocated between the transport systems could markedly affect the operation of CCM. Indeed, our simulations suggest that various combinations of Ci fluxes can provide a possible approach to detect the way by which the cell distributes energy produced by the photosystems to the two active Ci transport processes. The proportion of the energy consumed on CCM to the total energy expenditure for the fixation of one CO2 molecule was determined at 18%–40%.     

Effects of light quality on growth rates and pigments of Chaetoceros gracilis (Bacillariophyceae)

Light is an important parameter in algal culturing. In this work, the effects of different light qualities on growth of the marine diatom Chaetoceros gracilis are evaluated. The cells were cultured under light quantum flux density of 60 µmol photons/(m2·s) with nine light qualities: LED red light (LR), LED blue light (LB), LED red plus LED blue light (LR+LB), LED white light (LW), fluorescent white light (FW), and combinations of LW and FW lights with increased proportions of red or blue light (FW+LR, FW+LB, LW+LR, and LW+LB). Blue light promoted the growth of C. gracilis largely. Three light qualities, FW+LR, LW+LR, and LR, resulted in the lowest growth rate. Both chlorophyll and carotenoids reached the highest level under LB and the lowest level under LR among monochromatic light sources; however, increasing of the proportion of blue or red light in the white light induced an increase of the chlorophyll and carotenoid concentrations. Light absorption ability of microalgae was critical for the growth of these organisms, as we observed a positive correlation between the extinction coefficient at different wavelengths and the specific growth rate. These findings are of importance to improve the culturing of this alga in bioreactors.     

Effects of different light conditions on repair of UV-B-induced damage in carpospores of Chondrus ocellatus Holm

We evaluated the effects of ultraviolet-B(UV-B) radiation and different light conditions on the repair of UV-B-induced damage in carpospores of C hondrus ocellatus Holm(Rhodophyta) in laboratory experiments. Carpospores were treated daily with different doses of UV-B radiation for 48 days,when vertical branches had formed in all treatments; after each daily treatment,the carpospores were subjected to photosynthetically active radiation(PAR),darkness,red light,or blue light during a 2-h repair stage. Carpospore diameters were measured every 4 days. We measured the growth and cellular contents of cyclobutane pyrimidine dimers(CPDs),chlorophyll a,phycoerythrin,and UV-B-absorbing mycosporine-like amino acids(MAAs) in carpospores on Day 48. Low doses of UV-B radiation(36 and 72 J/m 2) accelerated the growth of C. ocellatus. However,as the amount of UV-B radiation increased,the growth rate decreased and morphological changes occurred. UV-B radiation significant damaged DNA and photosynthetic pigments and induced three kind of MAAs,palythine,asterina-330,and shinorine. PAR conditions were best for repairing UV-B-induced damage. Darkness promoted the activity of the DNA darkrepair mechanism. Red light enhanced phycoerythrin synthesis but inhibited light repair of DNA. Although blue light,increased the activity of DNA photolyase,greatly improving remediation efficiency,the growth and development of C. ocellatus carpospores were slower than in other light treatments.     

集成夜间灯光数据与Landsat TM影像的不透水面自动提取方法研究

利用多源遥感数据提取不透水面信息是一个重要的研究方向。针对以往研究中多需要人工选取不透水面样本进行模型训练的问题,本文通过整合夜间灯光遥感与Landsat TM影像中的空间和光谱信息实现了不透水面覆盖范围（Impervious Surface Area,ISA）的自动提取。首先根据夜间灯光的分布来定位ISA聚集的城市区域的位置,分别在城市区域内部和外部自动提取可靠性高的ISA及非ISA样本,然后通过迭代分类提取城市区域的ISA,再以此为样本对城市区域外部进行分类,最后将分类结果整合完成整幅影像的ISA提取流程。应用本方法对美国雪城地区的DMSP/OLS夜间灯光影像上提取了84个城市区域,提取精度大于95%。从中分别选择高ISA密度和低ISA密度的2个城市区域作为ISA提取的测试区,本文方法在城市区域内的ISA提取总体精度与kappa系数分别为88.23%和0.63;在城市区域外部为78.6%和0.54,均优于人工样本选取方法的提取精度,表明该方法能够实现精度稳定且高效的ISA自动提取。     

Effects of blue light on gametophyte development of Laminaria japonica (Laminariales, Phaeophyta)

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).