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Water-soluble Fraction (water-soluble + fraction)
Selected AbstractsAlteration of normal cellular profiles in the scleractinian coral (Pocillopora damicornis) following laboratory exposure to fuel oilENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 12 2006Luc Rougée Abstract Petroleum contamination from oil spills is a continuing threat to our ocean's fragile ecosystems. Herein, we explored the effects of the water-soluble fraction of crude oil on a stony coral, Pocillopora damicornis (Linneaeus 1758). We developed methods for exposing corals to various concentrations of crude oil and for assessing the potential molecular responses of the corals. Corals were exposed to water-accommodated fraction solutions, and appropriate cellular biomarkers were quantified. When compared to the "healthy" control specimens, exposed corals exhibited shifts in biomarker concentrations that were indicative of a shift from homeostasis. Significant changes were seen in cytochrome P450 1-class, cytochrome P450 2-class, glutathione- S -transferase-pi, and cnidarian multixenobiotic resistance protein-1 biomarkers, which are involved the cellular response to, and manipulation and excretion of, toxic compounds, including polycyclic aromatic hydrocarbons. A shift in biomarkers necessary for porphyrin production (e.g., protoporphyrinogen oxidase IX and ferrochelatase) and porphyrin destruction (e.g., heme oxygenase-1 and invertebrate neuroglobin homologue) illustrates only one of the cellular protective mechanisms. The response to oxidative stress was evaluated through measurements of copper/zinc superoxide dismutase-1 and DNA glycosylase MutY homologue-1 concentrations. Likewise, changes in heat shock protein 70 and small heat shock proteins indicated an adjustment in the cellular production of proteins. Finally, the results of this laboratory study were nearly identical to what we observed previously among corals of a different species, Porites lobata, exposed to an oil spill in the field after the grounding of the Merchant Vessel Kyowa Violet. [source] A test of the community conditioning hypothesis: Persistence of effects in model ecological structures dosed with the jet fuel jp-8ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 2 2000Wayne G. Landis Abstract The foundation of the community conditioning hypothesis, the persistence of effects, was tested in a series of microcosm experiments. Experiments were conducted with the water-soluble fraction of the turbine fuel JP-8 using the standard protocols for the standardized aquatic microcosm (SAM). A repeat trial was conducted using the SAM protocol but with a 126-d test period, twice the standard duration. The results were examined using a variety of conventional univariate, multivariate, and graphical techniques. The principal conclusions were as follows. Effects are persistent in these model ecological systems long after the degradation of the toxicant. Patterns of impacts are detectable at concentrations 15 times lower than an experimentally derived single-species EC50. The replicate experiments are not replicable in the specific, but the broad pattern of the disruption of algal- herbivore dynamics followed by more subtle effects are consistently repeated. The durability of the indirect effects and therefore the information about historical events appears to be a consistent feature of these microcosm systems. The identity of the treatment groups persists. The critical features of the community conditioning hypothesis,persistence of information within ecologicalsystems and the reappearance of patterns and therefore the nonequilibrium dynamics,are again confirmed. The implications of these findings for environmental toxicology, monitoring, and ecological risk assessment are discussed. [source] Influence of Cultivation System on Bioactive Molecules Synthesis in Strawberries: Spin-off on Antioxidant and Antiproliferative ActivityJOURNAL OF FOOD SCIENCE, Issue 1 2010L. D'Evoli ABSTRACT:, Strawberries (Fragaria ananassa,L., cv. favette) were studied to investigate the influence of cultivation practices (biodynamic, conventional) on the synthesis of bioactive molecules (ascorbic acid, ellagic acid, anthocyanins, flavonols) and to evaluate their antioxidant activity. Additionally, the,in vitro,bioactivity, in terms of antioxidant and antiproliferative activity, of the same strawberry samples in human colon carcinoma (Caco-2) cells was also studied. Compared to conventional strawberries, biodynamic fruits had a significantly higher content of ascorbic acid (P,< 0.01), pelargonidin-3-glucoside (P,< 0.05), cyanidin-3-glucoside (P,< 0.01), ellagic acid (P,< 0.01), quercetin, and kaempferol (both,P,< 0.01). Antioxidant activity of biodynamic strawberry crude extract was significantly higher than that of the conventional one (P,< 0.05); in addition, while the antioxidant activity of water-soluble fraction was very similar in both biodynamic and conventional strawberries, that of water-insoluble fraction of biodynamic fruits was significantly higher (P,< 0.05). The same crude extract of biodynamic strawberry samples effectively corresponded to an increase of bioactivity, in terms of both cellular antioxidant activity and antiproliferative activity, in Caco-2 cells differentiated to normal intestinal epithelia and in undifferentiated Caco-2, respectively. Further studies are needed to confirm whether the practice of biodynamic agriculture is likely to increase the bioactivity of other varieties of fruits and vegetables. [source] Influence of the Coagulant Level on Early Proteolysis in Ovine Cheese-like Systems Made with Sterilized Milk and Cynara cardunculusJOURNAL OF FOOD SCIENCE, Issue 7 2004S.V. Silva ABSTRACT: The effect of coagulant level on the quality and quantity of protein breakdown during the first 24 h of ripening of cheese-like systems, manufactured with sterilized ovine milk using crude aqueous extracts of Cynara cardunculus as coagulant, was experimentally assessed. Urea-polyacrylamide gel electrophoresis was performed on both water-soluble and water-insoluble cheese extracts to monitor the casein degradation pattern; the ripening extension index and the ripening depth index were thus calculated. Peptides from the water-soluble fraction were isolated by reverse-phase, high-performance liquid chromatography and partially sequenced by Edman degradation. Higher residual coagulant levels in curdled milk led to earlier breakdown of caseins, as expected. The primary cleavage sites were Phe105-Met106 in k-casein, Phe23-Val24 in ,s1 -casein, and Leu127-Thr128, Ser142-Trp143, Leu165-Ser166, and Leu190-Tyr191 in ,-casein. [source] Preparation and functional properties of extracts from bee breadMOLECULAR NUTRITION & FOOD RESEARCH (FORMERLY NAHRUNG/FOOD), Issue 3 2004Takeshi Nagai Abstract Three extracts, namely hot-water fraction (HWF), water-soluble fraction (WSF), and ethanol-soluble fraction (ESF), were prepared from fresh bee bread imported from Lithuania. The protein and total phenolic contents of these samples were very high. Among them, WSF at 100% concentration showed the highest antioxidative ability and scavenging ability. On the other hand, ESF at 10% concentration possessed the highest ability against 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydroxyl radicals. Bee bread will apply more and more as health food and medicine due to its functional properties such as antioxidative ability and scavenging activities of reactive oxygen species. [source] Immunomodulatory effect of extracts of Hibiscus sabdariffa L. (Family Malvaceae) in a mouse modelPHYTOTHERAPY RESEARCH, Issue 5 2008Titilayo O. Fakeye Abstract The immunomodulatory activity of water and alcohol extracts (including its fractions) of the dried calyx of the plant was evaluated in mice. The ability of the extracts to inhibit or enhance the production of two cytokines, namely tumor necrosis factor-alpha (TNF- ,) and interleukin-10 (IL-10), respectively, implicated as proinflammatory and antiinflammatory interleukins were also evaluated. The extracts at doses of 50 mg/kg were found to possess higher immunostimulatory activities in comparison with levamisole (positive control), with significant effects when compared with the vehicle-treated group (p < 0.01). Increased activity was observed with increase in doses of the 50% ethanol and absolute ethanol extracts. The insoluble fraction exhibited a significant dose-dependent immunostimulatory activity (p < 0.05), while the residual water-soluble fraction exhibited activity at 100 mg/kg body weight. The production of tumor necrosis factor-alpha (TNF- ,), was low in all the extract groups tested, while the production of interleukin 10 (IL-10) was high compared with the control. The production of IL-10 was high in 300 mg/kg aqueous extract. The insoluble fraction exhibited a profound dose-dependent immunostimulatory activity higher than the positive control at 100 mg/kg. This study established the immunoenhancing properties of the extracts of this plant confirming that the immunomodulatory activity is cell mediated and humoral. The insoluble fraction could find use as an immunostimulatory agent in humans. Copyright © 2008 John Wiley & Sons, Ltd. [source] Estrogenic effect of leachates and soil extracts from lysimeters spiked with sewage sludge and reference endocrine disruptersENVIRONMENTAL TOXICOLOGY, Issue 2 2002Halim Dizer Abstract Several experiments were conducted to evaluate the behavior and performance of some potential endocrine disrupters (ECDs). Two in vitro screening assays, one based on MCF7-cell proliferation (E-screen test) and the other on estrogenic receptor activity [enzyme-linked receptor assay (ELRA)], were used for the tests, which were done in lysimeters 80 cm in diameter with depths of 30 cm (shallow) or 90 cm (deep). A sandy soil was used to fill in all lysimeters, which were spiked on the surface with either: (a) a sewage sludge (SS) at a dose equivalent to 20 tons ha,1; (b) a mixture of reference ECDs, comprising 17,- and 17,-estradiol (E2), nonylphenol, octylphenol, and bisphenol A at doses 100 times higher than the maximum concentrations respectively found in the applied SS; or (c) a mixture of ECDs and SS. After percolation of the lysimeters with rain and/or artificial water, five leachates were sampled from each lysimeter during a period of 210 days. Immediately after the lysimeter percolation experiments, four and six soil fractions were dissected from, respectively, the 30-cm and 90-cm lysimeters and extracted by water. Both the leachate and soil extract samples were analyzed for their estrogenicity using the assays indicated above. The E-screen assay was highly sensitive only for some leachate and extract samples but gave no response for most leachates and soil extracts. The results of the ELRA assay suggests a significantly higher estrogenicity of leachate samples from shallow lysimeters compared with that of leachates from deep lysimeters. In contrast, the estrogenic effect measured for soil extracts of shallow lysimeters was lower than that measured for soil extracts of deep lysimeters. The results of the E-screen assay suggests the occurrence of a fast mobilization of applied ECDs and a moderate retardation effect of native ECDs contained in applied SS in the sandy soil used in the lysimeters. In lysimeters spiked with a mixture of SS and ECDs, the washing-out effect of ECDs in the first leachate fraction decreased, but the distribution of ECDs in the lysimeters increased. The relatively high estrogenic impact measured for soil water extracts suggests that the ECDs were mostly associated with water-soluble fractions of organic matter and/or water-suspended fractions of the mineral soil matrix. The application of SS to agricultural and forest fields may determine the immobilization of ECDs in soil or their movement to surface and/or groundwater. Therefore, an endocrine risk of exposure exists for the water and soil organisms. © 2002 Wiley Periodicals, Inc. Environ Toxicol 17: 105,112, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/tox.10038 [source] | ||||||||||