66 resultados para Cladophora.


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A description of the algal genus Cladophora from Vol 10 of the ”Freshwater Flora of Poland”. Illustrations are included.

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It was on July 1960 when 10 algal balls were acquired for exhibition at Suma Aquarium, Kobe. Permission to remove the specimens from the Lake Akan Reserve was given by the National Nature Reserve Committee. Algal balls, as a rule, lose their natural beauty when they are kept in an ordinary tank for a certain length of time. In an effort to retain the natural beauty it was decided to exhibit them in culture. This paper summarises the findings of this experiments with Cladophora sauteri. The author concludes that serious consideration has to be given as to the intensity of light, the sunlight, the water temperature and the nutrition for algal balls in culture in order to retain the natural beauty and shape.

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Chemical examination of the green alga Cladophora fascicularis resulted in the isolation and characterization of a new porphyrin derivative, porphyrinolactone (1), along with five known phaeophytins 2-6 and fourteen sterols and cycloartanes. The structure of 1 was determined on the basis of spectroscopic analyses and by comparison of its NMR data with those of known phaeophytins. Compounds 1-6 displayed moderate inhibition of tumor necrosis factor alpha (TNF-alpha) induced nuclear factor-kappa B (NF-kappa B) activation, while 2 and 4 displayed potential inhibitory activity toward proteasome chymotripsin-like activation. The primary structure-activity relationship was also discussed.

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Biosorption of Cr(VI) from aqueous solutions by nonliving green algae Cladophora albida was investigated in batch experiments. The influence of pH, algal dosage, initial Cr(VI) concentration, temperature and coexisting anions on removal efficiencies of C. albida was studied. Cr(VI) removal process was influenced significantly by the variation of pH, and the optimum pH was chosen at a range of 1.0-3.0. The optimum algal dosage 2 g/L was used in the experiment. The removal rate of Cr(VI) was relatively rapid in the first 60 min, but then the rate decreased gradually. Removal mechanism was studied by analyzing Cr(VI) and total Cr in the solution. Biosorption and bioreduction were involved in the Cr(VI) removal. Biosorption of Cr(VI) was the first step. followed by Cr(VI) bioreduction and Cr(III) biosorption on the algal biomass. Actual industrial wastewater was used to evaluate the practicality of the biomass C. albida. From a practical viewpoint, the abundant and economic biomass C. albida could be used for removal of Cr(VI) from wastewater by the reduction of toxic Cr(VI) to less toxic Cr(III). (C) 2008 Elsevier Ltd. All rights reserved.

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The adsorption and desorption of algae Cladophora fascicularis and their relation with initial Cd2+ concentration, initial pH, and co-existing ions were studied. Adsorption equilibrium and biosorption kinetics were established from batch experiments. The adsorption equilibrium was adequately described by the Langmuir isotherm, and biosorption kinetics was in pseudo-second order model. The experiment on co-existing ions showed that the biosorption capacity of biomass decreased with an increasing concentration of competing ions. Desorption experiments indicated that EDTA was efficient desorbent for recovery from Cd2+. With high capacities of metal biosorption and desorption, the biomass of Cladophora fascicularis is promising as a cost-effective biosorbent for the removal of Cd2+ from wastewater.

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Biosorption is an effective means of removal of heavy metals from wastewater. In this work the biosorption behavior of Cladophora fascicularis was investigated as a function of pH, amount of biosorbent, initial Cu2+ concentration, temperature, and co-existing ions. Adsorption equilibria were well described by Langmuir isotherm models. The enthalpy change for the biosorption process was found to be 6.86 kJ mol(-1) by use of the Langmuir constant b. The biosorption process was found to be rapid in the first 30 min. The presence of co-existing cations such as Na+, K+, Mg2+, and Ca2+ and anions such as chloride, nitrate, sulfate, and acetate did not significantly affect uptake of Cu2+ whereas EDTA substantially affected adsorption of the metal. When experiments were performed with different desorbents the results indicated that EDTA was an efficient desorbent for the recovery of Cu2+ from biomass. IR spectral analysis suggested amido or hydroxy, C=O, and C-O could combine strongly with Cu2+.

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Biosorption is an effective method to remove heavy metals from wastewater. In this work, adsorption features of Cladophora fascicularis were investigated as a function of time, initial pH, initial Pb(II) concentrations, temperature and co-existing ions. Kinetics and equilibria were obtained from batch experiments. The biosorption kinetics followed the pseudo-second order model. Adsorption equilibria were well described by the Langmuir and Freundlich isotherm models. The maximum adsorption capacity was 198.5 mg/g at 298 K and pH 5.0. The adsorption processes were endothermic and the biosorption heat was 29.6 kJ/mol. Desorption experiments indicated that 0.01 mol/L Na(2)EDTA was an efficient desorbent for the recovery of Pb(II) from biomass. IR spectrum analysis suggested amido or hydroxy, C=O and C-O could combine intensively with Pb(II). (C) 2006 Elsevier B.V. All rights reserved.

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Biosorption of Cu2+ and Pb2+ by Cladophora fascicularis was investigated as a function of initial pH, initial heavy metal concentrations, temperature and other co-existing ions. Adsorption equilibriums were well described by Langmuir and Freundlich isotherm models. The maximum adsorption capacities were 1.61 mmol/ g for Cu2+ and 0.96 mmol/ g for Pb2+ at 298K and pH 5.0. The adsorption processes were endothermic and biosorption heats calculated by the Langmuir constant b were 39.0 and 29.6 kJ/ mol for Cu2+ and Pb2+, respectively. The biosorption kinetics followed the pseudo- second order model. No significant effect on the uptake of Cu2+ and Pb2+ by co-existing cations and anions was observed, except EDTA. Desorption experiments indicated that Na(2)EDTA was an efficient desorbent for the recovery of Cu2+ and Pb2+ from biomass. The results showed that Cladophora fascicularis was an effective and economical biosorbent material for the removal and recovery of heavy metal ions from wastewater.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Excessive Cladophora growth in the Great Lakes has led to beach fouling and the temporary closure of nuclear power plants and has been associated with avian botulism and the persistence of human pathogens. As the growth-limiting nutrient for Cladophora, phosphorus is the appropriate target for management efforts. Dreissenids (zebra and quagga mussels) have the ability to capture particulate phase phosphorus (otherwise unavailable to Cladophora) and release it in a soluble, available form. The significance of this potential nutrient source is, in part, influenced by the interplay between phosphorus flux from the mussel bed and turbulent mixing in establishing the phosphorus levels to which Cladophora is exposed. It is hypothesized that under quiescent conditions phosphorus will accumulate near the sediment-water interface, setting up vertical phosphorus gradients and favorable conditions for resource delivery to Cladophora. These gradients would be eliminated under conditions of wind mixing, reducing the significance of the dreissenid-mediated nutrient contribution. Soluble reactive phosphorus (SRP) levels were monitored over dreissenid beds (densities on the order of 350•m-2 and 3000∙m-2) at a site 8 m deep in Lake Michigan. Monitoring was based on the deployment of Modified Hesslein Samplers which collected samples for SRP analysis over a distance of 34 cm above the bottom in 2.5 cm intervals. Deployment intervals were established to capture a wind regime (calm, windy) that persisted for an interval consistent with the sampler equilibration time of 7 hours. Results indicate that increased mussel density leads to an increased concentration boundary layer; increased wind speed leads to entrainment of the concentration boundary layer; and increased duration of quiescent periods leads to an increased concentration boundary layer. This concentration boundary layer is of ecological significance and forms in the region inhabited by Cladophora

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"EPA-600/3-76-044."

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Nuisance growths of Cladophora have been associated with eutrophication. A review of the literature, however, reveals a scarcity of relevant experimental growth studies. Sampling experimental streams reveals that the addition of sewage effluent to good quality water alters the flora from that dominated by Potamogetan crispus to one dominated by CLadophora. Spatial and temporal differences in biomass of taxa present are discussed in the context of accompanying physicochemical data. In laboratory batch culture, growth of unialgal C. glomerata was accompanied by elevation of medium pH - considered largely responsible for the poor growth in such culture. However, appropriate experimental conditions and indices of growth were selected and the effects of various herbicides assessed. Diquat and terbutryne were shown to possess algicidal activity towards Cladophora. A closed continuous culture apparatus was developed: growth proceeded through lag, logarithmic and linear phases. Inoculum size and medium flow rate had significant effects on growth, and were standardized. In continuous culture, specific growth rate increased linearly with increased duration of light per day, up to 24 hours, and increased light intensity, up to 6000 lux - the highest intensity tested. Comparison of field and laboratory results suggests that ammonia toxicity is attributable to the undissociated form. In the laboratory, 185 µg/1 undissociated ammoniacal nitrogen reduced specific growth rate to 50% of that at 10 µg/1 undissociated ammcniacal nitrogen. 0.077-1.057 mg/1 NO2-N had no significant effect on growth. 7.2-15.2 mg/1 NO3-N had no significant effect on specific growth rate. Neither was any nitrate/phosphate interaction significant. At 4.9 mg/1 PO4-1, specific growth rate was only 48% of that at 1.9 g/1 P04-P. The critical medium PO4-P concentration was <0.1 mg/i. Specific growth rate was reduced to 50% of that in natural water by 0.036 mgCu/l, 0.070 mgzn/1 and 1.03 mgPb/l. Metal uptake was evaluated.

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Species of Pithophora occasionally appear in Europe and are associated mostly with the tropical, higher water plants, cultivated in numerous botanical gardens. In June 1973 pale green, branched threads were discovered in the pond of the Wroclaw Botanical Garden, amongst filaments of Spirogyra crassa (Kutz.) Czurda emend. and Cladophora glomerata (L.) Kutz. floating on the water surface. They were maintained for several weeks in crude cultures and produced numerous, dark akinetes tightly packed with reserve material. This collected material was found to be a member of the family Pithophora, Wittr. Further examinations identified the material as Pithophora oedogonia. The findings point out that it is probable, that species of Pithophora Wittr. can become acclimatized in Europe, primarily in ponds of botanical gardens, where consequently they are able to tangle easily with higher tropical plants.

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Mats (biomasses) of macroalgae, i.e. Ulva spp., Enteromorpha spp., Graciolaria spp., and Cladophora spp., have increased markedly over the past 50 years, and they cover much larger areas than they once did in many estuaries of the world. The increases are due to large inputs of pollutants, mainly nitrates. During the warm months, the mats lie loosely on shallow sand and mud flats mostly along shorelines. Ulva lactuca overwinters as buds attached to shells and stones, and in the spring it grows as thalli (leaf fronds). Mats eventually form that are several thalli thick. Few macroinvertebrates grow on the upper surfaces of their thalli due to toxins they produce, and few can survive beneath them. The fish, crabs, and wading birds that once used the flats to feed on the macroinvertebrates are denied these feeding grounds. The mats also grow over and kill mollusks and eelgrass, Zostera marina. An experiment was undertaken which showed that two removals of U. lactuca in a summer from a shallow flat in an estuarine cove maintained the bottom almost free of it.

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Twelve commonly occurring coenocytic and siphonaceous species of marine benthic algae, i.e., Bryopsis pennatta Lamouroux, Caulerpa chemnitzia (Esper) Lamouroux, Ca. faridii Nizamuddin, Ca. manorensis Nizamuddin, Ca. racemosa (Forsskal) J. Agardh, Ca. taxifolia. (Vahl) C. Agardh, Chaetomorpha antennina (Bory de Saint-Vincent) Kutzing, Cladophora uncinella Harvey, Codium decorticatum (Woodward) Howe, Co. flabellatum Nizamuddin, Co. iyengarii Borgesen, and Valoniopsis pachynema (Martens) Borgesen, belonging to four different orders of the class Bryopsidophyceae, division Chlorophyta, were collected from the intertidal region of different coastal areas near Karachi (Pakistan) and investigated taxonomically. Codium decorticatum is a new report from this region and Co. decorticatum, Co. flabellatum and Co. iyengarii are described for the first time from the coast of Pakistan.