Impacts of restoration of an uncontrolled phosphogypsum dumpsite on the seasonal distribution of abiotic variables, phytoplankton, copepods, and ciliates in a man-made solar saltern

The restoration of an uncontrolled phosphogypsum landfill was investigated for its effects on the seasonal distribution of phytoplankton, ciliates, and copepods. Sampling was carried out monthly from September 2007 to August 2008 at four ponds of increasing salinity (A1, 41 psu; A5, 46 psu; A16, 67 psu; and C31, 77 psu) in the Sfax solar saltern (southeastern Tunisia). Physicochemical and biological analyses were carried out using standard methods. Results showed drastic reduction of phosphate input and greater diversity of phytoplankton, ciliates, and copepods than before restoration. Pennate diatoms and new ciliates, considered bio-indicators of less-stressed marine ecosystems, proliferated in the A1 pond for the first time after restoration. Copepods appeared to feed on a wide range of prey. Economically, removal of the 1.7 million m³ of phosphate improved the quality of the site’s salt production, enabling the salt company to receive the quality ISO 9001 accreditation.     

Seasonal variation of some heavy metal pollution with environmental and microbiological parameters in sub-basin of Kocabas Stream (Biga, Canakkale, Turkey) by ICP-AES

Waste water pollution in industrial areas is one of the most important environmental problems. Heavy metal pollution, especially chromium species in waste water sources from tannery affects our lives. Kocabas Stream is located in south-west Marmara region and Biga town is positioned in the sub basin on the stream. This water source functions as the water for irrigation in agriculture, drinking water for animals and for human use. Thus, this study is of great importance. Waste water pollution can affect all ecosystems and human health by directly or indirectly as in food chain. The concentration of heavy metals (Pb, Cd, Cu, Zn and Cr) were pre-analysed by ICP-AES method in water samples taken from sub-basin of Kocabas stream. In the results of these analyses, concentrations of the metals except chromium were founded at the limit value. But the total concentration of the Cr was found at high levels of between 0.0082 +/- 0.0001 and 5.7231 +/- 0.0921 mg l(-1) over the limit value (0.05 mg l(-1); WHO, EPA, TSE 266 and inland water quality classification) at sampling points very close to tannery factories. Also physicochemical and microbiological parameters of Kocabas Stream were determined. The effects of the experimental results on environment were investigated.     

Effect of pH on Anti-Rotavirus Activity by Comestible Juices and Proanthocyanidins in a Cell-Free Assay System

Cranberry (Vaccinium macrocarpon) and grape (Vitis labrusca) juices, and these species?? secondary plant metabolites [i.e., proanthocyanidins (PACs)] possess antiviral activity. An understanding of the mechanism(s) responsible for these juices and their polyphenolic constituents?? direct effect on enteric virus integrity, however, remains poorly defined. Using the rotavirus (RTV) as a model enteric virus system, the direct effect of manufacturer-supplied and commercially purchased juices [Ocean Spray Pure Cranberry 100?% Unsweetened Juice (CJ), Welch??s 100?% Grape Juice (GJ), 100?% Concord (PG) and 100?% Niagara juices (NG)] and these species?? cranberry (C-PACs) and grape PACs (G-PACs) was investigated. Loss of viral capsid integrity in cell-free suspension by juices and their PACs, and as a factor of pH, was identified by an antigen (RTV) capture enzyme-linked immunosorbent assay. At native and an artificially increased suspension at or near pH 7, loss of viral infectivity occurred after 5?min, in the order CJ?>?NG?=?GJ?>?PG, and PG?>?GJ?=?NG?=?CJ, respectively. Antiviral activity of CJ was inversely related to pH. Grape, but not cranberry PACs, displayed a comparatively greater anti-RTV activity at a suspension pH of 6.7. Anti-RTV activity of C-PACs was regained upon reduction of RTV-cranberry PAC suspensions to pH 4. An alteration or modification of Type A PAC (of V. macrocarpon) structural integrity at or near physiologic pH is suggested to have impacted on this molecule??s antivirus activity. Type B PACs (of V. labrusca) were refractive to alternations of pH. Significantly, findings from pure system RTV?CPAC testing paralleled and in turn, supported those RTV-juice antiviral studies. Electron microscopy showed an enshroudment by PACs of RTV particles, suggesting a blockage of viral antigenic binding determinants. The implications of our work are significant, especially in the interpretation of PAC (and PAC-containing food)?CRTV interactions in the differing [pH] conditions of the gastrointestinal tract.     

Evaluation of physical, chemical and microbiological properties of lake Uluabat, Turkey

Lake Uluabat, known for its scenic beauty and richness of aquatic life, is situated in Marmara Region, Bursa (Turkey). On account of its importance, lake Uluabat was designated by the Ministry of Environment as a Ramsar site in 1998. Physical, chemical and microbiological parameters of the aquatic ecosystem in lake Uluabat were measured monthly at five stations from February 2003 to January 2004. The results showed that lake Uluabat can be classified as Class I with respect to temperature (16.36 +/- 7.47 degrees C), nitrate nitrogen (0.63 +/- 0.50 mgl(-1)), sodium (9.64 +/- 2.78 mgl(-1)), chloride (20.45 +/- 4.59 mgl(-1)), sulphate (54.80 +/- 29.97 mgl(-1)); as Class II with respect to dissolved oxygen (7.62 +/- 1.99 mgl(-1)), ammonium nitrogen (0.52 +/- 0.49 mgl(-1)), chemical oxygen demand (35.74 +/- 10.66 mgl(-1)), total coliform (2027 MPN100 ml(-1) (average value)); as Class III with respect to pH (8.69 +/- 0.16) and as Class IV with respect to total nitrogen (84.94 +/- 66.13 mgl(-1)), total phosphorus (1.11 +/- 3.01 mgl(-1)), biochemical oxygen demand (21.21 +/- 6.60 mgl(-1)) according to TWPCR (Turkey Water Pollution Control Regulation). The nutrient content of lake waterapparently indicated that lake had an eutrophic characteristic. Phosphorus was determined as a limiting factor in lake. The measured hardness values (140.94 +/- 14.61 CaCO3 mgl(-1)) indicated that lake water was classified as soft/hard during the study period. Eutrophic characteristic of the lake and contaminant accumulation in water will probably affect the future use of the lake. Therefore, pollution parameters must be regularly monitored and evaluated according to aquatic living and local regulations.     

Effects of pyrene on mussels in different experimental conditions

The toxicity of the polyaromatic hydrocarbon pyrene to Mytilus edulis and Mytilus galloprovincialis was investigated in experiments conducted in the United Kingdom for M. edulis and in Turkey for M. galloprovincialis. Experimental conditions of temperature and salinity were chosen to be appropriate to the ambient conditions in which the mussels typically live. The effect of different feeding regimes on pyrene bioaccumulation and toxicity was also investigated. Feeding rate and neutral red retention biomarker techniques were used for toxicity assessment. An experiment with M. edulis demonstrated that mussels exposed to pyrene accumulated increasing amounts of this compound throughout a 15-day exposure period and that accumulation increased in relation to exposure concentration and with increasing concentration of unicellular algal food material. However, in these experiments, which were protected from UV light, there was no clear relationship between pyrene concentration in tissues and feeding rate. A clear concentration-response relationship was observed between tissue concentration and neutral red retention for days 1 and 7 of the experiment, but this relationship was lost by day 15, with evidence of the cells recovering. A similar experiment was conducted with M. galloprovincialis at a single (high) pyrene concentration in darkness. The feeding rate of the exposed mussels was always lower than the feeding rate of the control mussels, although the difference was insignificant at 7-day exposure. A decreasing trend in health status of the mussels was indicated by the neutral red retention assay results after 7 and 15 days of exposure to pyrene. In a third experiment (with M. galloprovincialis), an illuminated algal chemostat system containing pyrene was inserted in the exposure system as the food source for the mussels. Both biomarker results showed conclusively that toxic effects correlated with pyrene bioaccumulation, though there was no clear evidence for light-enhanced toxicity. These experiments showed that experimental conditions such as salinity, temperature and feeding regime and perhaps the species of mussel used may influence whether pyrene is perceived as being a toxic molecule.     

Hepatic effects of yttrium oxide nanoflowers: in vitro risk evaluation

Yttrium oxide nanoflowers were prepared by a hydrothermal technique, and X-ray diffraction and scanning electron microscopy were used to determine their structures. The cytotoxic and genotoxic potentials of aqueous dispersions of the nanoflowers to cultured primary rat hepatocytes were examined at concentrations up to 500 mg L^?1 for 72 h. Cell viability was determined by monitoring the reduction of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, release of lactate dehydrogenase, and uptake of neutral red. Genotoxicity was assessed by the liver micronucleus assay. Exposure to Y₂O₃ nanoflowers at concentrations lower than 100 mg L^?1 did not lead to any cytotoxicity or genotoxicity. At higher concentrations (200, 400, and 500 mg L^?1), cell viability decreased and induction of micronuclei increased (400 and 500 mg L^?1).     

Export quality,economic growth,and renewable-nonrenewable energy use: non-linear evidence through regime shifts

Environmental Science and Pollution Research - Since export has a key role in economic growth in terms of national production quantity, export quality can be considered another important factor...     

Conception of an environmental friendly O/W cosmetic emulsion from microalgae

The development of eco-friendly cosmetic such as those from microalgae for skin regeneration and collagen synthesis has gained a great interest worldwide. Accordingly, the potential of microalgae biomass as source of anti-aging cosmetic cream with high antioxidant activity has been investigated. Stabilities and sensory characteristics of cosmetic creams supplemented with Spirulina, Tetraselmis sp. and Dunaliella sp. at 0.5, 1.5 and 2.5%, respectively, revealed a conservation of physico-chemical and preliminary stability properties of formulations. To analyze physico-chemical and textural parameters, accelerated stability study was evaluated under two thermal conditions (25 and 40 °C) during 90 days. Results showed that pH values of all formulations were within the limits of normal skin pH range under storage time at 25 and 40 °C. During this period, the colored creams showed a significant changes of a* and b* indices, reflecting the instability of microalgae colors. Microalgae modified the textural characteristics of emulsions. The Tetraselmis sp. containing-cream had the lowest (P < 0.05)?values of hardness, springiness, and cohesiveness. The 0.5% Spirulina containing-cream had the best stable consistency and adhesiveness under time and temperature variations. It exhibited the best properties to be used for skin care products. Thanks to their high content in bioactive macromolecules, microalgae considerably improved the antioxidant activity of the new formulated skin creams.

     

Insights into the Viscoelastic Peculiarities of Cyanobacterial Extracellular Polymeric Substance (EPS)

Journal of Polymers and the Environment - Extracellular polymeric substances (EPSs) can be defined as renewable, high molecular weight polymeric materials produced by bacteria and microorganisms....