The Mesozoic and Cenozoic strata in the Junggar basin developed two sets of shallow to semi-deep lacustrine shale, namely, the Cretaceous Qingshuihe Formation (K_(1q)) and the Paleogene Anjihaihe Formation (E_(2-3a))....The Mesozoic and Cenozoic strata in the Junggar basin developed two sets of shallow to semi-deep lacustrine shale, namely, the Cretaceous Qingshuihe Formation (K_(1q)) and the Paleogene Anjihaihe Formation (E_(2-3a)). Through organic petrology and scanning electron microscope (SEM) observation, it is found that the primary hydrocarbon-generating organic matter (OM) in the two sets of strata is different. The biological precursor of the E_(2-3a) OM is mainly green algae (Pediastrum), while the precursor of K_(1q) kerogen is mainly cyanobacteria (Oscillatoria). Then, the E_(2-3a) green algae-rich shale and K_(1q) cyanobacteria-rich shale were subjected to hydrous pyrolysis and kinetic analysis, respectively. The results show that the evolution modes of hydrocarbon generation of the typical shales are very different. Green algae have the characteristics of a low oil generation threshold, heavy oil quality, and no prominent oil peak, while cyanobacteria have the characteristics of late oil generation, concentrated hydrocarbon generation, and relatively light oil quality. The characteristics of oil generation can also be well reflected in the composition evolution of the crude oil components. The carbon isotope of gas, kerogen, and extracts of the E_(2-3a) green algae-rich shale are significantly heavier than the K_(1q) cyanobacteria-rich shale, which may be related to the living habits of their biological precursors, carbon source usage, photosynthesis efficiency, and carbon fixation efficiency.展开更多
This study analyzes the community structure, the quantity changes of the algae and the effect of important environmental factors and estimates the total biomass of the attached green algae in the survey areas. The stu...This study analyzes the community structure, the quantity changes of the algae and the effect of important environmental factors and estimates the total biomass of the attached green algae in the survey areas. The study uses data from surveys of the attached green algae on the Porphyra yezoensis aquaculture rafts and data regarding the environmental factors from October 2010 to April 2011 in the Subei Shoal. The attached green algae on the rafts included Ulva prolifera, Capsosiphon groenlandicus, U. linza, U. intestinalis, U. clathrata, and U. cornpressa. The biomass changes of the attached green algae exhibited an inverted parabola: the biomass was the highest (14 898 t) in April, and was the second highest (2 034 t) in November; it was lowest in February (only 729 t) and increased sharply from March to April. The species diversity differed significantly among the seasons. In September and October, when the P. yezoensis aquaculture rafts were initially set up, the attached green algae had a high biodiversity, while from December to the next February, a variety of green algae species coexisted on the rafts, although the biomass was low, and from March to April, as the biomass increased sharply, the species diversity dropped to the minimum. During this time, C. groenlandicus was apparently dominant with the maximum biomass proportion up to 80%, while the U. prolifera proportion increased exponentially to 20% to 40%. The water temperature had a direct regulating effect on the biomass and the species succession of the attached green algae. The estimation of the community dynamics and the biomass of the green algae provided the evidence needed to track the origin of the large-scale green tide in the southern Yellow Sea.展开更多
The toxicity of methyl tert-butyl ether (MTBE) to Chlorella ellipsoidea and Aphanizomenon flos-aquae was tested and assessed for a 15-d incubation with concentrations of MTBE from high (2.00×10^4 mg/L) to low...The toxicity of methyl tert-butyl ether (MTBE) to Chlorella ellipsoidea and Aphanizomenon flos-aquae was tested and assessed for a 15-d incubation with concentrations of MTBE from high (2.00×10^4 mg/L) to low (2 mg/L). The results showed that the toxicity was low when the concentration of MTBE was in the range 1.00× 10^4-2.00× 10^4 mg/L (the greatest inhibition of growth-rate was 70%-71%, occurred during the day 1-5). Low concentrations (2-500 rag/L) stimulated algal growth up to the greatest effect of 85%-200% when the concentration of MTBE was 50-100 mg/L during day 3-5. The toxicity of MTBE (72-120 h EC50) was 6.65×10^3-9.58×10^3 mg/L for C. ellipsoidea and that is 1.14× 10^4-2.00× 10^4 mg/L for A. floc-aquae. We found that the toxicity and ecological risk of MTBE for the algal community structure were low and the toxicity was influenced by the duration time of the test.展开更多
Silver nanoparticles,endowed with powerful antimicrobial property,are the most widely used nanomaterial in consumer products,with associated risk of their easy access to environment and freshwater ecosystems by surfac...Silver nanoparticles,endowed with powerful antimicrobial property,are the most widely used nanomaterial in consumer products,with associated risk of their easy access to environment and freshwater ecosystems by surface runoff.Although toxic effects of nanosilver on bacterial,fungal and mammalian cells have been documented,its impact on algal growth remains unknown.Pithophora oedogonia and Chara vulgaris are predominant members of photosynthetic eukaryotic algae,which form major component of global aquatic ecosystem.Here we report for the first time that nanosilver has significant adverse effects on growth and morphology of these filamentous green algae in a dose-dependent manner.Exposure of algal thalli to increasing concentrations of silver nanoparticles resulted in progressive depletion in algal chlorophyll content,chromosome instability and mitotic disturbance,associated with morphological malformations in algal filaments.SEM micrographs revealed dramatic alterations in cell wall in nanoparticle-treated algae,characterized with cell wall rupture and degradation in Pithophora.Although these observations underscore severe deleterious effects of nanosilver on aquatic environment,the information can also be exploited as a bioengineering strategy to control unwanted and persistent growth of noxious algal weeds that clog the municipal water supply and water channels and produce fouling of water bodies.展开更多
Chemical investigation of the ethanol extract of the marine green alga Chaetomorpha basiretorsa Setchell led to the isolation of a new sterol stigmast-4,28-dien-3α,6β-diol 1 in addition to the five known sterols of ...Chemical investigation of the ethanol extract of the marine green alga Chaetomorpha basiretorsa Setchell led to the isolation of a new sterol stigmast-4,28-dien-3α,6β-diol 1 in addition to the five known sterols of β-lawsaritol 2, saringosterol 3, 24-hydroperoxy-24-vinyl - cholesterol 4, β-stigmasterol 5, 29-hydroxystigmasta-5, 24 (28) -dien-3β-ol 6. Compounds were isolated by normal phase silica gel and Sephadex LH - 20 gel colum chromatography, reverse phase HPLC and recrystalization. Their structures were elucidated by spectroscopic methods including MS, IR 1D/2D NMR and X-ray analysis. Cytotoxicity of compounds was screened by using the standard MTF method. All these compounds were isolated from the green alga Chaetomorpha basiretorsa Setchell for the first time and they were inactive (50% inhibitory concentration was greater than 10 μg/cm^3) against KB, Bel -7402, PC - 3M, Ketr 3 and MCF-7 cell lines.展开更多
All algae documented so far are of unknown origin. Here, we provide a taxonomic description of the first origin-known alga TDX16-DE that arises from the <i><span style="font-family:Verdana;">Chro...All algae documented so far are of unknown origin. Here, we provide a taxonomic description of the first origin-known alga TDX16-DE that arises from the <i><span style="font-family:Verdana;">Chroococcidiopsis</span></i><span style="font-family:Verdana;">-like endosymbiotic cyanobacterium TDX16 by de novo organelle biogenesis after acquiring its green algal host</span><i><span style="font-family:Verdana;"> Haematococcus pluvialis</span></i><span style="font-family:Verdana;">’s DNA. TDX16-DE is spherical or oval, with a diameter of 2.0-3.6 μm, containing typical chlorophyte pigments of chlorophyll a, chlorophyll b and lutein and reproducing by autosporulation, whose 18S rRNA gene sequence shows the highest similarity of 99.7% to that of </span><i><span style="font-family:Verdana;">Chlorella vulgaris</span></i><span style="font-family:Verdana;">. However, TDX16-DE is only about half the size of</span><i><span style="font-family:Verdana;"> C. vulgaris </span></i><span style="font-family:Verdana;">and structurally similar to</span><i><span style="font-family:Verdana;"> C. vulgaris</span></i><span style="font-family:Verdana;"> only in having a chloroplast-localized pyrenoid, but differs from</span><i><span style="font-family:Verdana;"> C. vulgaris</span></i><span style="font-family:Verdana;"> in that 1) it possesses a double-membraned cytoplasmic envelope but lacks endoplasmic reticulum and Golgi apparatus;and 2) its nuc</span><span style="font-family:Verdana;">leus is enclosed by two sets of envelopes (four</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">unit membranes). Therefore</span><span style="font-family:;" "=""><span style="font-family:Verdana;">, based on these characters and the cyanobacterial origin, we describe TDX16-DE as a new genus and species, </span><i><span style="font-family:Verdana;">Chroococcidiorella tianjinensis</span></i><span style="font-family:Verdana;"> gen. et sp. nov., which sets the basis for multidisciplinary research.</span></span>展开更多
To provide theoretical and technical basis for the application of preparations of bamboo vinegar and copper sulfate in the prevention of green algae in floating system for tobacco seeding,the soaking and spraying meth...To provide theoretical and technical basis for the application of preparations of bamboo vinegar and copper sulfate in the prevention of green algae in floating system for tobacco seeding,the soaking and spraying methods were employed to study the effect of different concentrations of preparations of bamboo vinegar and copper sulfate on green algae and tobacco seedling growth. The results showed that the preparations of bamboo vinegar and copper sulfate of different concentrations played a strong role in inhibiting green algae growth and had better effect than copper sulfate. Spraying 1∶ 200 preparations of bamboo vinegar and copper sulfate could significantly promote tobacco seedling growth,and the leaf fresh weight increased by 15. 80% compared with CK,with significant difference; spraying 1∶ 50 preparations was not conducive to tobacco seedling growth. It was recommended to spray 1∶ 200 preparations of bamboo vinegar and copper sulfate in floating system for tobacco seeding,which could promote tobacco seedling growth and reduce green algae to varying degrees.展开更多
Microcystins (MCYSTs) isolated from blue-green algae,are hepatotoxic polypeptides.It will induce severe intrahepatic hemorrhage and liver necrosis at low concentrations in rats and mice.MCYST- LR is one of MCYSTs whic...Microcystins (MCYSTs) isolated from blue-green algae,are hepatotoxic polypeptides.It will induce severe intrahepatic hemorrhage and liver necrosis at low concentrations in rats and mice.MCYST- LR is one of MCYSTs which consists of 2 variable L- amino acids(leucine and arginine),3 D-amino acids and 2 unusualamino acids(including Adda).MCYSTs bind to protein phosphatase 1 and 2A,and strongly inhibit their activities.The resultant increase of phosphoprotein was referred to be involved in tumor-promoting activity in liver.According to the above results and animal study,MCYST-LR is a potent liver tumor promoter.There were 9 positive from 30 samples of pond-ditch water in high endemic county-Haimen by high-peformance liquid chromatograph and 3 already confirmed by liquid chromograph/mass spectrometer.The quantities of MCYSTs were different between drinking water of liver cancer cases and controls groups.122±0.057and 0.072±0.044μg/200ml respectively) by ELISA. It is not easy to remove by conventional water treatment procedures.The relationship between MCYSTs and oncogenes and anti-oncogenes are under studying.展开更多
Reduced walleye (<i></span><i><span style="font-family:Verdana;">Sander vitreus</span></i><span style="font-family:Verdana;"></i></span><spa...Reduced walleye (<i></span><i><span style="font-family:Verdana;">Sander vitreus</span></i><span style="font-family:Verdana;"></i></span><span style="font-family:Verdana;">) fingerling production possibly related to nuisance filamentous green algae and overly</span></span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">stable water chemistry patterns is a concern in earthen-substrate ponds at Blue Dog State Fish Hatchery, South Dakota, USA. We describe the success of alfalfa (<i></span><i><span style="font-family:Verdana;">Medicago sativa</span></i><span style="font-family:Verdana;"></i></span><span style="font-family:Verdana;">) meal (AFM, n</span></span><span style="font-family:""> </span><span style="font-family:Verdana;">=</span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">2), alfalfa meal plus soybean (<i></span><i><span style="font-family:Verdana;">Glycine max</span></i><span style="font-family:Verdana;"></i></span><span style="font-family:Verdana;">) meal (AFM</span></span><span style="font-family:""> </span><span style="font-family:Verdana;">+</span><span style="font-family:""> </span><span style="font-family:Verdana;">SBM, n</span><span style="font-family:""> </span><span style="font-family:Verdana;">=</span><span style="font-family:""> </span><span style="font-family:Verdana;">1), and alfalfa meal plus liquid 28N:0P:0K (AFM</span><span style="font-family:""> </span><span style="font-family:Verdana;">+</span><span style="font-family:""> </span><span style="font-family:Verdana;">28:0:0, n</span><span style="font-family:""> </span><span style="font-family:Verdana;">=</span><span style="font-family:""> </span><span style="font-family:Verdana;">1) at achieving</span><span style="font-family:Verdana;"> walleye production objectives (>104,000 walleye and 32 kilograms/hectare) as well as the occurrence of filamentous green algae and the associated patterns of ammonia-nitrogen, pH, and dissolved oxygen in earthen-substrate ponds. Walleye production objectives were only achieved when filamentous green algae were absent preceding harvest, which occurred in one pond that received AFM and in the pond that received AFM</span><span style="font-family:""> </span><span style="font-family:Verdana;">+</span><span style="font-family:""> </span><span style="font-family:Verdana;">28:0:0.</span><span style="font-family:""> </span><span style="font-family:Verdana;">The presence of filamentous green algae preceding harvest was associated with higher dissolved oxygen and pH, whereas declines in these variables occurred when filamentous green algae were absent. Organic fertilizer alone exhibited low ammonia-nitrogen (<0.1 mg/L) despite the substitution of higher protein content soybean meal, but supplementation with 28:0:0 increased ammonia-nitrogen to 0.23 mg/L. These findings highlight the reduction in walleye fingerling production that occurred in the presence of filamentous green algae and the unpredictability of results when two earthen-substrate ponds are treated exactly the same with alfalfa meal. Achievement of walleye production objectives, lack of nuisance filamentous green algae, and promotion of</span><span style="font-family:""> </span><span style="font-family:Verdana;">favorable patterns in water chemistry warrant future experimentation with alfalfa meal supplemented with 28:0:0 in earthen-substrate ponds at this hatchery.展开更多
Based on the experience and lessons from previous control of lakes, as well as the present situation of water eutrophication and outbreak of blue-green algae in lakes, general ideas of controlling outbreak of blue-gre...Based on the experience and lessons from previous control of lakes, as well as the present situation of water eutrophication and outbreak of blue-green algae in lakes, general ideas of controlling outbreak of blue-green algae in large and middle lakes were proposed. Firstly, it is needed to control serious outbreak of blue-green algae and then build health aquatic ecosystems and corresponding control goals finally. Secondly, quantity of blue-green algae in lakes and lake eutrophication should be reduced at the same time. Thirdly, quantity of reduced blue-green algae must exceed the natural increase of them in quantity persistently, so that outbreak of blue-green algae will reduce and even be eliminated. Fourthly, engineering measures and corresponding safeguard measures to control outbreak of blue-green algae in lakes should be combined.展开更多
In general, many pollutants co\|exist in natural aquatic ecosystems. They affect each other and occur different results, such as synergism, addition and antagonism. So the research at mixtoxicity of contaminants to aq...In general, many pollutants co\|exist in natural aquatic ecosystems. They affect each other and occur different results, such as synergism, addition and antagonism. So the research at mixtoxicity of contaminants to aquatic organism is more important than monotoxicity. In this paper, 50% effectual inhibition concentration 48h \%EC\%\-\{50\} values of 6 kinds of nitroaromatic compounds to the green algae, \%Scenedesmus obliquus,\% were investigated. Mixtoxic experiments, in which any combination of 2,4\|DNT and other 6 kinds of compounds, indicate: (1) synergisms between 2,4\|DNT and 4\|NAn, as well as 4\|NAnis, 1,4\|DNB; (2) antagonisms between 2,4\|DNT and 4\|NT, as well as 4\|NPh, 4\|NCB.展开更多
Macroalgae blooms of Ulva prolifera have occurred every summer in the southern Yellow Sea since 2007,inducing severe ecological problems and huge economic losses.Genesis and secular movement of green algae blooms have...Macroalgae blooms of Ulva prolifera have occurred every summer in the southern Yellow Sea since 2007,inducing severe ecological problems and huge economic losses.Genesis and secular movement of green algae blooms have been well monitored by using remote sensing and other methods.In this study,green algae were detected and traced by using Geostationary Ocean Color Imager(GOCI),and a novel biomass estimation model was developed from the relationship between biomass measurements and previously published satellite-derived biomass indexes.The results show that the green algae biomass can be determined most accurately with the biomass index of green algae for GOCI(BIGAG),which is calculated from the Rsurf data that had been atmospherically corrected by ENVI/QUAC method.For the first time,dynamic changes in green algae biomass were studied over an hourly scale.Short-term biomass changes were highly influenced by Photosynthetically Available Radiation(PAR)and tidal phases,but less by sea surface temperature variations on a daily timescale.A new parameter of biomass changes(PBC),calculated by the ratio of the biomass growth rate to movement velocity,could provide an effective way to assess and forecast green tide in the southern Yellow Sea and similar areas.展开更多
Combining some information from field investigation of algae along the coastal areas in China and a few pictures materialized from the western Yellow Sea in 2008,authors analyze the necessary conditions and possible w...Combining some information from field investigation of algae along the coastal areas in China and a few pictures materialized from the western Yellow Sea in 2008,authors analyze the necessary conditions and possible water area in China producing a large biomass,some reasons for firestorm,and the possibility of the reappearance of marine bloom green alga Enteromorpha prolifera.The change of habitats and the increase of nutritional levels related to the water area could be considered as direct reasons.It was transferred northward by the combination of the flow of rainwater,wind and alongshore marine current.The original region of large biomass produced is possibly located in the southwestern Yellow sea.It will possibly be appearing again in the coming years or in the future.A summary is also given referring to its reproduction,development and distribution worldwide.展开更多
Hollow B–SiO2@TiO2 composites were prepared by the wet chemical deposition method starting from TiCl4 and hollow B–SiO2 microspheres.TiO2 layers composed of anatase TiO2 nanoparticles were coated on the surfaces of ...Hollow B–SiO2@TiO2 composites were prepared by the wet chemical deposition method starting from TiCl4 and hollow B–SiO2 microspheres.TiO2 layers composed of anatase TiO2 nanoparticles were coated on the surfaces of the hollow B–SiO2 microspheres probably through the formation of Ti—O—Si and Ti—O—B bonds.A great number of—OH groups were also present at the TiO2 coating layers.The presence of Ti—O—Si bonds and Ti—O—B bonds resulted in the formation of defects in the TiO2 coating layers,which decreased the band gap of the TiO2 coating layers to ca.3.0 eV and endowed the TiO2 coating layers with visible light absorption performance.The buoyancy hollow B–SiO2@TiO2 composites exhibited high photocatalytic activities for the degradation of ammonia-nitrogen and green algae.The conversion of ammonia-nitrogen reached 65%when the degradation of ammonia-nitrogen(43 mg·L-1 at pH value of 8)was catalyzed by the B–SiO2@TiO2(100:10)composite under the simulated solar light irradiation at 35°C for 660 min.The green algae(5 mg·L-1)were almost completely degraded over the B–SiO@TiO2(100:20)photocatalyst under the visible light irradiation at 35°C for 510 min.展开更多
Objective:To identify the available phytochemicals and carotenoids in the selected green algae and evaluate the potential genotoxic/antigenotoxic effect using lymphocytes.Methods:Organic,solvent extracts of Chlorococc...Objective:To identify the available phytochemicals and carotenoids in the selected green algae and evaluate the potential genotoxic/antigenotoxic effect using lymphocytes.Methods:Organic,solvent extracts of Chlorococcum humicola(C.humicola)were used for the phytochemical analysis.The available carotenoids were assessed by HPLC,and LC-MS analysis.The genotoxicity was induced by the benzo(a)pyrene in the lymphocyte culture,the genotoxic and antigenotoxic effects of algal carotenoids with and without genotoxic inducer were evaluated by chromosomal aberration(CA),sister chromatid exchange(SCE)and micronucleus assay(MN).Results:The results of the analysis showed that the algae were rich in carotenoids and fatty acids.In the total carotenoids lutein,β-carotene andα-carotene were found to be present in higher concentration.The frequency of CA and SCE increased by benzo(a)pyrene were significantly decreased by the carotenoids(P<0.05 for CA,P<0.001 for SCE).The MN frequencies of the cells were significantly decreased by the treatment with carotenoids when compared with the positive controls(P<0.05).Conclusions:The findings of the present study demonstrate that,the green algae C.humicola is a rich source of bioactive compounds especially carotenoids which effectively fight against environmental genotoxic agents,the carotenoids itself is not a genotoxic substance and should be further considered for its beneficial effects.展开更多
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 F, strain) using a rapid method based on ultrasonic...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 F, 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 OOC 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.展开更多
Six cycloartanes were isolated from ethanol extract of marine green alga Cladophora fas-cicularis by column chromatography. Procedure of isolation and description of these compounds are given in this paper. The struct...Six cycloartanes were isolated from ethanol extract of marine green alga Cladophora fas-cicularis by column chromatography. Procedure of isolation and description of these compounds are given in this paper. The structures were elucidated as (1). 24-hydroperoxycycloart-25(26)-en-3β-ol; (2). cycloart-25(26)-en-3β 24-diol; (3). 25-hydroperoxycycloart-23-en-3β-ol; (4). cycloart-23-en-3β, 25-diol; (5). cycloart-23, 25(26)-dien-3β-ol; and (6). cycloart-24-en-3β-ol by spectroscopic (MS, 1D and 2D NMR) data analysis. Cycloartane derivatives are widely distributed in terrestrial plants, but only few were ob-tained in the alga. All these compounds that have been isolated from terrestrial plants, were found in the marine alga for the first time.展开更多
The marine green alga Chaetomorpha valida fouls aquaculture ponds along the coastal cities of Dalian and Rongcheng, China. Unialgal cultures were observed under a microscope to determine the developmental morphologica...The marine green alga Chaetomorpha valida fouls aquaculture ponds along the coastal cities of Dalian and Rongcheng, China. Unialgal cultures were observed under a microscope to determine the developmental morphological characters of C. valida. Results reveal that gametophytic filaments often produce lateral branches under laboratory culture conditions, suggesting an atypical heteromorphic life cycle of C. valida between unbranched sporophytes and branched gametophytes, which differs from typical isomorphic alternation of Chaetomorpha species. The shape of the basal attachment cell, an important taxonomic character within the genus, was found variable depending on environmental conditions. The 18S rDNA and 28S rDNA regions were used to explore the phylogenetic affinity of the taxa. Inferred trees from 18S rDNA sequences revealed a close relationship between C. valida and Chaetomorpha moniligera. These results would enrich information in general biology and morphological plasticity of C. valida and provided a basis for future identification of green tide forming algae.展开更多
基金supported by Xinjiang Oilfield Company of China(No.2020-C4006).
文摘The Mesozoic and Cenozoic strata in the Junggar basin developed two sets of shallow to semi-deep lacustrine shale, namely, the Cretaceous Qingshuihe Formation (K_(1q)) and the Paleogene Anjihaihe Formation (E_(2-3a)). Through organic petrology and scanning electron microscope (SEM) observation, it is found that the primary hydrocarbon-generating organic matter (OM) in the two sets of strata is different. The biological precursor of the E_(2-3a) OM is mainly green algae (Pediastrum), while the precursor of K_(1q) kerogen is mainly cyanobacteria (Oscillatoria). Then, the E_(2-3a) green algae-rich shale and K_(1q) cyanobacteria-rich shale were subjected to hydrous pyrolysis and kinetic analysis, respectively. The results show that the evolution modes of hydrocarbon generation of the typical shales are very different. Green algae have the characteristics of a low oil generation threshold, heavy oil quality, and no prominent oil peak, while cyanobacteria have the characteristics of late oil generation, concentrated hydrocarbon generation, and relatively light oil quality. The characteristics of oil generation can also be well reflected in the composition evolution of the crude oil components. The carbon isotope of gas, kerogen, and extracts of the E_(2-3a) green algae-rich shale are significantly heavier than the K_(1q) cyanobacteria-rich shale, which may be related to the living habits of their biological precursors, carbon source usage, photosynthesis efficiency, and carbon fixation efficiency.
基金The National Basic Research Program (973 Program) of China under contract No.2010CB428703the National Natural Science Foundation of China under contract No.41306171+3 种基金the National Research Foundation-Shandong Province United Fund under contract No.U1406403the Qingdao Public Domain to Support Science and Technology Project under contract No.13–4–1–68–hythe Marine and Basic Research Funds of the First Institute of Oceanography,SOA under contract No.2015G09MOST International S&T Cooperation Program under contract No.2010DFA24340
文摘This study analyzes the community structure, the quantity changes of the algae and the effect of important environmental factors and estimates the total biomass of the attached green algae in the survey areas. The study uses data from surveys of the attached green algae on the Porphyra yezoensis aquaculture rafts and data regarding the environmental factors from October 2010 to April 2011 in the Subei Shoal. The attached green algae on the rafts included Ulva prolifera, Capsosiphon groenlandicus, U. linza, U. intestinalis, U. clathrata, and U. cornpressa. The biomass changes of the attached green algae exhibited an inverted parabola: the biomass was the highest (14 898 t) in April, and was the second highest (2 034 t) in November; it was lowest in February (only 729 t) and increased sharply from March to April. The species diversity differed significantly among the seasons. In September and October, when the P. yezoensis aquaculture rafts were initially set up, the attached green algae had a high biodiversity, while from December to the next February, a variety of green algae species coexisted on the rafts, although the biomass was low, and from March to April, as the biomass increased sharply, the species diversity dropped to the minimum. During this time, C. groenlandicus was apparently dominant with the maximum biomass proportion up to 80%, while the U. prolifera proportion increased exponentially to 20% to 40%. The water temperature had a direct regulating effect on the biomass and the species succession of the attached green algae. The estimation of the community dynamics and the biomass of the green algae provided the evidence needed to track the origin of the large-scale green tide in the southern Yellow Sea.
基金supported by the National Natural Science Foundation of China (No. 20476099)
文摘The toxicity of methyl tert-butyl ether (MTBE) to Chlorella ellipsoidea and Aphanizomenon flos-aquae was tested and assessed for a 15-d incubation with concentrations of MTBE from high (2.00×10^4 mg/L) to low (2 mg/L). The results showed that the toxicity was low when the concentration of MTBE was in the range 1.00× 10^4-2.00× 10^4 mg/L (the greatest inhibition of growth-rate was 70%-71%, occurred during the day 1-5). Low concentrations (2-500 rag/L) stimulated algal growth up to the greatest effect of 85%-200% when the concentration of MTBE was 50-100 mg/L during day 3-5. The toxicity of MTBE (72-120 h EC50) was 6.65×10^3-9.58×10^3 mg/L for C. ellipsoidea and that is 1.14× 10^4-2.00× 10^4 mg/L for A. floc-aquae. We found that the toxicity and ecological risk of MTBE for the algal community structure were low and the toxicity was influenced by the duration time of the test.
基金supported by grants received by Anjali Dash from DST Women Scientist Scheme (DST WOSA)by D.Dash from the Department of Biotechnology (DBT),Govt.of Indiathe Indian Council of Medical Research (ICMR)
文摘Silver nanoparticles,endowed with powerful antimicrobial property,are the most widely used nanomaterial in consumer products,with associated risk of their easy access to environment and freshwater ecosystems by surface runoff.Although toxic effects of nanosilver on bacterial,fungal and mammalian cells have been documented,its impact on algal growth remains unknown.Pithophora oedogonia and Chara vulgaris are predominant members of photosynthetic eukaryotic algae,which form major component of global aquatic ecosystem.Here we report for the first time that nanosilver has significant adverse effects on growth and morphology of these filamentous green algae in a dose-dependent manner.Exposure of algal thalli to increasing concentrations of silver nanoparticles resulted in progressive depletion in algal chlorophyll content,chromosome instability and mitotic disturbance,associated with morphological malformations in algal filaments.SEM micrographs revealed dramatic alterations in cell wall in nanoparticle-treated algae,characterized with cell wall rupture and degradation in Pithophora.Although these observations underscore severe deleterious effects of nanosilver on aquatic environment,the information can also be exploited as a bioengineering strategy to control unwanted and persistent growth of noxious algal weeds that clog the municipal water supply and water channels and produce fouling of water bodies.
基金supported by national 863 project(Grant No.2004AA625030,2001AA620503)NNSFC(Grant No.20432030)Key Innovative Project of the Academy(Grant No.KZCX3-SW-215).
基金The State"863" High Tech Programof China under contract Nos 2007 AA09Z410 and 2007 AA091604Key Innovative Project of the Chinese Academy of Sciences under contract No.KZCX2-YW-209.
文摘Chemical investigation of the ethanol extract of the marine green alga Chaetomorpha basiretorsa Setchell led to the isolation of a new sterol stigmast-4,28-dien-3α,6β-diol 1 in addition to the five known sterols of β-lawsaritol 2, saringosterol 3, 24-hydroperoxy-24-vinyl - cholesterol 4, β-stigmasterol 5, 29-hydroxystigmasta-5, 24 (28) -dien-3β-ol 6. Compounds were isolated by normal phase silica gel and Sephadex LH - 20 gel colum chromatography, reverse phase HPLC and recrystalization. Their structures were elucidated by spectroscopic methods including MS, IR 1D/2D NMR and X-ray analysis. Cytotoxicity of compounds was screened by using the standard MTF method. All these compounds were isolated from the green alga Chaetomorpha basiretorsa Setchell for the first time and they were inactive (50% inhibitory concentration was greater than 10 μg/cm^3) against KB, Bel -7402, PC - 3M, Ketr 3 and MCF-7 cell lines.
文摘All algae documented so far are of unknown origin. Here, we provide a taxonomic description of the first origin-known alga TDX16-DE that arises from the <i><span style="font-family:Verdana;">Chroococcidiopsis</span></i><span style="font-family:Verdana;">-like endosymbiotic cyanobacterium TDX16 by de novo organelle biogenesis after acquiring its green algal host</span><i><span style="font-family:Verdana;"> Haematococcus pluvialis</span></i><span style="font-family:Verdana;">’s DNA. TDX16-DE is spherical or oval, with a diameter of 2.0-3.6 μm, containing typical chlorophyte pigments of chlorophyll a, chlorophyll b and lutein and reproducing by autosporulation, whose 18S rRNA gene sequence shows the highest similarity of 99.7% to that of </span><i><span style="font-family:Verdana;">Chlorella vulgaris</span></i><span style="font-family:Verdana;">. However, TDX16-DE is only about half the size of</span><i><span style="font-family:Verdana;"> C. vulgaris </span></i><span style="font-family:Verdana;">and structurally similar to</span><i><span style="font-family:Verdana;"> C. vulgaris</span></i><span style="font-family:Verdana;"> only in having a chloroplast-localized pyrenoid, but differs from</span><i><span style="font-family:Verdana;"> C. vulgaris</span></i><span style="font-family:Verdana;"> in that 1) it possesses a double-membraned cytoplasmic envelope but lacks endoplasmic reticulum and Golgi apparatus;and 2) its nuc</span><span style="font-family:Verdana;">leus is enclosed by two sets of envelopes (four</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">unit membranes). Therefore</span><span style="font-family:;" "=""><span style="font-family:Verdana;">, based on these characters and the cyanobacterial origin, we describe TDX16-DE as a new genus and species, </span><i><span style="font-family:Verdana;">Chroococcidiorella tianjinensis</span></i><span style="font-family:Verdana;"> gen. et sp. nov., which sets the basis for multidisciplinary research.</span></span>
文摘To provide theoretical and technical basis for the application of preparations of bamboo vinegar and copper sulfate in the prevention of green algae in floating system for tobacco seeding,the soaking and spraying methods were employed to study the effect of different concentrations of preparations of bamboo vinegar and copper sulfate on green algae and tobacco seedling growth. The results showed that the preparations of bamboo vinegar and copper sulfate of different concentrations played a strong role in inhibiting green algae growth and had better effect than copper sulfate. Spraying 1∶ 200 preparations of bamboo vinegar and copper sulfate could significantly promote tobacco seedling growth,and the leaf fresh weight increased by 15. 80% compared with CK,with significant difference; spraying 1∶ 50 preparations was not conducive to tobacco seedling growth. It was recommended to spray 1∶ 200 preparations of bamboo vinegar and copper sulfate in floating system for tobacco seeding,which could promote tobacco seedling growth and reduce green algae to varying degrees.
文摘Microcystins (MCYSTs) isolated from blue-green algae,are hepatotoxic polypeptides.It will induce severe intrahepatic hemorrhage and liver necrosis at low concentrations in rats and mice.MCYST- LR is one of MCYSTs which consists of 2 variable L- amino acids(leucine and arginine),3 D-amino acids and 2 unusualamino acids(including Adda).MCYSTs bind to protein phosphatase 1 and 2A,and strongly inhibit their activities.The resultant increase of phosphoprotein was referred to be involved in tumor-promoting activity in liver.According to the above results and animal study,MCYST-LR is a potent liver tumor promoter.There were 9 positive from 30 samples of pond-ditch water in high endemic county-Haimen by high-peformance liquid chromatograph and 3 already confirmed by liquid chromograph/mass spectrometer.The quantities of MCYSTs were different between drinking water of liver cancer cases and controls groups.122±0.057and 0.072±0.044μg/200ml respectively) by ELISA. It is not easy to remove by conventional water treatment procedures.The relationship between MCYSTs and oncogenes and anti-oncogenes are under studying.
文摘Reduced walleye (<i></span><i><span style="font-family:Verdana;">Sander vitreus</span></i><span style="font-family:Verdana;"></i></span><span style="font-family:Verdana;">) fingerling production possibly related to nuisance filamentous green algae and overly</span></span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">stable water chemistry patterns is a concern in earthen-substrate ponds at Blue Dog State Fish Hatchery, South Dakota, USA. We describe the success of alfalfa (<i></span><i><span style="font-family:Verdana;">Medicago sativa</span></i><span style="font-family:Verdana;"></i></span><span style="font-family:Verdana;">) meal (AFM, n</span></span><span style="font-family:""> </span><span style="font-family:Verdana;">=</span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">2), alfalfa meal plus soybean (<i></span><i><span style="font-family:Verdana;">Glycine max</span></i><span style="font-family:Verdana;"></i></span><span style="font-family:Verdana;">) meal (AFM</span></span><span style="font-family:""> </span><span style="font-family:Verdana;">+</span><span style="font-family:""> </span><span style="font-family:Verdana;">SBM, n</span><span style="font-family:""> </span><span style="font-family:Verdana;">=</span><span style="font-family:""> </span><span style="font-family:Verdana;">1), and alfalfa meal plus liquid 28N:0P:0K (AFM</span><span style="font-family:""> </span><span style="font-family:Verdana;">+</span><span style="font-family:""> </span><span style="font-family:Verdana;">28:0:0, n</span><span style="font-family:""> </span><span style="font-family:Verdana;">=</span><span style="font-family:""> </span><span style="font-family:Verdana;">1) at achieving</span><span style="font-family:Verdana;"> walleye production objectives (>104,000 walleye and 32 kilograms/hectare) as well as the occurrence of filamentous green algae and the associated patterns of ammonia-nitrogen, pH, and dissolved oxygen in earthen-substrate ponds. Walleye production objectives were only achieved when filamentous green algae were absent preceding harvest, which occurred in one pond that received AFM and in the pond that received AFM</span><span style="font-family:""> </span><span style="font-family:Verdana;">+</span><span style="font-family:""> </span><span style="font-family:Verdana;">28:0:0.</span><span style="font-family:""> </span><span style="font-family:Verdana;">The presence of filamentous green algae preceding harvest was associated with higher dissolved oxygen and pH, whereas declines in these variables occurred when filamentous green algae were absent. Organic fertilizer alone exhibited low ammonia-nitrogen (<0.1 mg/L) despite the substitution of higher protein content soybean meal, but supplementation with 28:0:0 increased ammonia-nitrogen to 0.23 mg/L. These findings highlight the reduction in walleye fingerling production that occurred in the presence of filamentous green algae and the unpredictability of results when two earthen-substrate ponds are treated exactly the same with alfalfa meal. Achievement of walleye production objectives, lack of nuisance filamentous green algae, and promotion of</span><span style="font-family:""> </span><span style="font-family:Verdana;">favorable patterns in water chemistry warrant future experimentation with alfalfa meal supplemented with 28:0:0 in earthen-substrate ponds at this hatchery.
文摘Based on the experience and lessons from previous control of lakes, as well as the present situation of water eutrophication and outbreak of blue-green algae in lakes, general ideas of controlling outbreak of blue-green algae in large and middle lakes were proposed. Firstly, it is needed to control serious outbreak of blue-green algae and then build health aquatic ecosystems and corresponding control goals finally. Secondly, quantity of blue-green algae in lakes and lake eutrophication should be reduced at the same time. Thirdly, quantity of reduced blue-green algae must exceed the natural increase of them in quantity persistently, so that outbreak of blue-green algae will reduce and even be eliminated. Fourthly, engineering measures and corresponding safeguard measures to control outbreak of blue-green algae in lakes should be combined.
基金Foundationitem :theNationalNaturalScienceFoundationofChina (No .992 90 60 0 )
文摘In general, many pollutants co\|exist in natural aquatic ecosystems. They affect each other and occur different results, such as synergism, addition and antagonism. So the research at mixtoxicity of contaminants to aquatic organism is more important than monotoxicity. In this paper, 50% effectual inhibition concentration 48h \%EC\%\-\{50\} values of 6 kinds of nitroaromatic compounds to the green algae, \%Scenedesmus obliquus,\% were investigated. Mixtoxic experiments, in which any combination of 2,4\|DNT and other 6 kinds of compounds, indicate: (1) synergisms between 2,4\|DNT and 4\|NAn, as well as 4\|NAnis, 1,4\|DNB; (2) antagonisms between 2,4\|DNT and 4\|NT, as well as 4\|NPh, 4\|NCB.
基金the National Natural Science Foundation of China(Nos.41776052,41476031)the Research Fund of State Key Laboratory of Marine Geology(No.MG20190104)the China Scholarship Council(No.CSC201906260052).
文摘Macroalgae blooms of Ulva prolifera have occurred every summer in the southern Yellow Sea since 2007,inducing severe ecological problems and huge economic losses.Genesis and secular movement of green algae blooms have been well monitored by using remote sensing and other methods.In this study,green algae were detected and traced by using Geostationary Ocean Color Imager(GOCI),and a novel biomass estimation model was developed from the relationship between biomass measurements and previously published satellite-derived biomass indexes.The results show that the green algae biomass can be determined most accurately with the biomass index of green algae for GOCI(BIGAG),which is calculated from the Rsurf data that had been atmospherically corrected by ENVI/QUAC method.For the first time,dynamic changes in green algae biomass were studied over an hourly scale.Short-term biomass changes were highly influenced by Photosynthetically Available Radiation(PAR)and tidal phases,but less by sea surface temperature variations on a daily timescale.A new parameter of biomass changes(PBC),calculated by the ratio of the biomass growth rate to movement velocity,could provide an effective way to assess and forecast green tide in the southern Yellow Sea and similar areas.
基金Supported by general and major projects of National Natural Science Foundation of China (Nos 40876081,30570125,and 30499340(partly)the National High Technology Research and Development Program of China (863 Program)(No 2008BAC49B01)Knowledge Innovation Project of Chinese Academy of Sciences (No KSCX2-YW-Z-018)
文摘Combining some information from field investigation of algae along the coastal areas in China and a few pictures materialized from the western Yellow Sea in 2008,authors analyze the necessary conditions and possible water area in China producing a large biomass,some reasons for firestorm,and the possibility of the reappearance of marine bloom green alga Enteromorpha prolifera.The change of habitats and the increase of nutritional levels related to the water area could be considered as direct reasons.It was transferred northward by the combination of the flow of rainwater,wind and alongshore marine current.The original region of large biomass produced is possibly located in the southwestern Yellow sea.It will possibly be appearing again in the coming years or in the future.A summary is also given referring to its reproduction,development and distribution worldwide.
基金Supported by the National Natural Science Foundation of China(21506078).
文摘Hollow B–SiO2@TiO2 composites were prepared by the wet chemical deposition method starting from TiCl4 and hollow B–SiO2 microspheres.TiO2 layers composed of anatase TiO2 nanoparticles were coated on the surfaces of the hollow B–SiO2 microspheres probably through the formation of Ti—O—Si and Ti—O—B bonds.A great number of—OH groups were also present at the TiO2 coating layers.The presence of Ti—O—Si bonds and Ti—O—B bonds resulted in the formation of defects in the TiO2 coating layers,which decreased the band gap of the TiO2 coating layers to ca.3.0 eV and endowed the TiO2 coating layers with visible light absorption performance.The buoyancy hollow B–SiO2@TiO2 composites exhibited high photocatalytic activities for the degradation of ammonia-nitrogen and green algae.The conversion of ammonia-nitrogen reached 65%when the degradation of ammonia-nitrogen(43 mg·L-1 at pH value of 8)was catalyzed by the B–SiO2@TiO2(100:10)composite under the simulated solar light irradiation at 35°C for 660 min.The green algae(5 mg·L-1)were almost completely degraded over the B–SiO@TiO2(100:20)photocatalyst under the visible light irradiation at 35°C for 510 min.
基金supported by Bharathiar University.Tamilnadu,India
文摘Objective:To identify the available phytochemicals and carotenoids in the selected green algae and evaluate the potential genotoxic/antigenotoxic effect using lymphocytes.Methods:Organic,solvent extracts of Chlorococcum humicola(C.humicola)were used for the phytochemical analysis.The available carotenoids were assessed by HPLC,and LC-MS analysis.The genotoxicity was induced by the benzo(a)pyrene in the lymphocyte culture,the genotoxic and antigenotoxic effects of algal carotenoids with and without genotoxic inducer were evaluated by chromosomal aberration(CA),sister chromatid exchange(SCE)and micronucleus assay(MN).Results:The results of the analysis showed that the algae were rich in carotenoids and fatty acids.In the total carotenoids lutein,β-carotene andα-carotene were found to be present in higher concentration.The frequency of CA and SCE increased by benzo(a)pyrene were significantly decreased by the carotenoids(P<0.05 for CA,P<0.001 for SCE).The MN frequencies of the cells were significantly decreased by the treatment with carotenoids when compared with the positive controls(P<0.05).Conclusions:The findings of the present study demonstrate that,the green algae C.humicola is a rich source of bioactive compounds especially carotenoids which effectively fight against environmental genotoxic agents,the carotenoids itself is not a genotoxic substance and should be further considered for its beneficial effects.
基金This research was supported in part by The President of The Chinese Academy of Sciences Foundation
文摘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 F, 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 OOC 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.
基金Supported by the National High-Tech R&D Program (863 Program) (Nos. 2001AA620403, 2003AA620403 and 2002AA217081) the State Major Basic Research Development Program of China (973 Program, No. 2002CB41240)+1 种基金 the Major Program of CAS (No. KJCX315-215) NSFC(Nos. 40176038, 30171106, and 30530080) and the International Cooperation Projects of BMBF-CNCBD
文摘Six cycloartanes were isolated from ethanol extract of marine green alga Cladophora fas-cicularis by column chromatography. Procedure of isolation and description of these compounds are given in this paper. The structures were elucidated as (1). 24-hydroperoxycycloart-25(26)-en-3β-ol; (2). cycloart-25(26)-en-3β 24-diol; (3). 25-hydroperoxycycloart-23-en-3β-ol; (4). cycloart-23-en-3β, 25-diol; (5). cycloart-23, 25(26)-dien-3β-ol; and (6). cycloart-24-en-3β-ol by spectroscopic (MS, 1D and 2D NMR) data analysis. Cycloartane derivatives are widely distributed in terrestrial plants, but only few were ob-tained in the alga. All these compounds that have been isolated from terrestrial plants, were found in the marine alga for the first time.
基金Supported by General and Major Projects of the National Natural Science Foundation of China(Nos.31070185,31093440)the Science and Technology Project of Guangdong Province(Nos.2011B031100010,2012A020200007)+3 种基金the Talent Introduction Projects of Guangdong Province Universities and Collegesthe Team Project of Natural Science Foundation of Guangdong Province(No.S2011030005257)the Grant of the Key Laboratory of Integrated Marine Monitoring and Applied Technologies for Harmful Algal Blooms,SOA(MATHAB)(No.MATHAB20100301)the Science and Technology Project of Shantou City,China(No.2011-162)
文摘The marine green alga Chaetomorpha valida fouls aquaculture ponds along the coastal cities of Dalian and Rongcheng, China. Unialgal cultures were observed under a microscope to determine the developmental morphological characters of C. valida. Results reveal that gametophytic filaments often produce lateral branches under laboratory culture conditions, suggesting an atypical heteromorphic life cycle of C. valida between unbranched sporophytes and branched gametophytes, which differs from typical isomorphic alternation of Chaetomorpha species. The shape of the basal attachment cell, an important taxonomic character within the genus, was found variable depending on environmental conditions. The 18S rDNA and 28S rDNA regions were used to explore the phylogenetic affinity of the taxa. Inferred trees from 18S rDNA sequences revealed a close relationship between C. valida and Chaetomorpha moniligera. These results would enrich information in general biology and morphological plasticity of C. valida and provided a basis for future identification of green tide forming algae.
基金Supported by High Technology Research and Development Program of China (863 Program) (No.2007AA09Z410 and 2007AA091604),NSFC of China (No.30530080)the Key Innovative Program,Chinese Academy of Sciences (No.KZCX2-YW-209).