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1.
Animals (Basel) ; 12(22)2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36428333

RESUMO

The aim of the research was to evaluate lactose content and rheological, physical, chemical, and organoleptic parameters during the storage of fermented beverages made from sheep's milk. The research was carried out on natural, probiotic, and Greek-type yogurts, as well as kefir. The products were made using the thermostat method from the milk of 42 East Frisian sheep in the middle lactation period, in duplicate. Lactose contents, active and titratable acidity, color by the L*a*b*C*h* system, and rheological parameters (hardness, consistency, consistency, and viscosity) were tested, and organoleptic assessments were carried out on the first, seventh, fourteenth, and twenty-first days of storing the drinks at 4 °C. Of all drinks, the highest reduction in lactose after 21 days of storage was found to occur in kefir (52% reduction) and, among the yogurts, in the Greek yogurt (41% reduction). The product with the lowest lactose content, regardless of the storage period, was kefir. This indicates that kefir is more suitable than yogurt for people with partial lactose intolerance. Effects of both inoculation type and beverage storage time were shown to exist for all parameters. It was also found that kefirs suffered deterioration in most rheological parameters and, in general organoleptic evaluation in the final period of storage. Based on our analysis, the optimal storage time for natural yogurts and sheep's milk kefirs at 4 °C was 21 and 14 days, respectively.

2.
Molecules ; 27(16)2022 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-36014366

RESUMO

The aim of this work was to study the possibility of using medicinal plants in combination with salt-containing raw materials from the Aral Sea region for cosmetic purposes. The chemical and mineralogical compositions of salts occurring in this region were studied for pharmacological and cosmetic purposes. The salt-containing raw materials were studied by X-ray diffraction (XRD), thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). The microflora of saline-containing raw materials and flora of the Zhaksy-Klych lake were studied. Fifty-six plant species were identified, of which 25% belong to the Asteraceae family, 32% were Poaceae, 22% were Amaranthaceae, and 21% were Tamaricaceae. Using the solid-phase microextraction (SPME) method and comprehensive two-dimensional gas chromatography−mass spectrometry, the composition of volatile compounds in such plant species as Artemisia alba L., Achilleamillifolium L., Eleagus commutate Bernh. Ex Rydb., Psoraleadrupacea Bunge, Artemisia cipa O. Vegd., Thymus vulgaris L., Morus alba L., Salvia pratensis L., Glycyrhizaglabra L., Tanacetum vulgare L., Polygonumaviculare L., Alhagipseudoalhagi Gagnebin and Peganumharmala L., chosen on the basis of their herbal components for future cosmetic products, was determined. In total, 187 different volatile compounds were found in the endemic plant species Glycyrrhizaglabra L., of which the following were dominant: 1,7-octadiene-3-, 2,6-dimethyl- with a peak area of 4.71%; caryophyllenes; bicyclo[7.2.0]4,11,11-trimethyl-8-methylene-, [1R-(1R*,4E,9S*)]­3.70%; bicyclo[2.2.1] heptane-2-1,7,7-trimethyl-,(1S)­3.46%; cyclohexanone, 5-methyl-2-(1-methylethyledene)-; 2-isopropyledene-5­2.97%; menthol; cyclohexanol, 5-methyl-2-(1-methylethyl)-; p-menthane-3-ol; menthol alcohol; and 2-isopropyl-5­2.08%. The remaining compounds were detected in amounts of less than 2.0%. Tests of seven cosmetic compositions developed on the basis of plant extracts and salt-containing raw materials revealed that three samples had a moisturizing effect. Launching the production of cosmetic products in the Aral region will not only reduce social tensions but also significantly improve the environmental situation in the region.


Assuntos
Artemisia , Plantas Medicinais , Cromatografia Gasosa-Espectrometria de Massas/métodos , Mentol , Extratos Vegetais/química , Plantas Medicinais/química
3.
Molecules ; 27(14)2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-35889521

RESUMO

Food, particularly milk and cheese, may be a reservoir of multi-drug resistant Staphylococcus aureus strains, which can be considered an important issue in terms of food safety. Furthermore, foods of animal origin can be a cause of staphylococcal food poisoning via the production of heat-stable enterotoxins (SE). For this reason, we investigated the prevalence of and characterized Staphylococcus aureus strains isolated from milk and fresh soft cheese obtained from farms located in Wielkopolskie and Zachodniopomorskie Provinces in Poland. Overall, 92% of S. aureus isolates were positive for at least one of the 18 enterotoxin genes identified, and 26% of the strains harbored 5 to 8 enterotoxin genes. Moreover, the S. aureus strains contained genes conferring resistance to antibiotics that are critically important in both human and veterinary medicine, i.e., ß-lactams (mecA), aminoglycosides (aac(6')/aph(2″), aph(3')-IIIa, ant(4')-Ia) and MLSB (erm(A), msr(A), lun(A)). The antimicrobial susceptibility of S. aureus to 16 antibiotics representing 11 different categories showed that 74% of the strains were resistant to at least 1 antibiotic. Moreover, 28% of the strains showed multidrug resistance; in particular, two methicillin-resistant S. aureus strains (MRSA) exhibited significant antibiotic resistance. In summary, our results show that dairy products are contaminated by S. aureus strains carrying genes encoding a variety of enterotoxins as well genes conferring resistance to antibiotics. Both MRSA strains and MSSA isolates showing multidrug resistance were present in foods of animal origin.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Animais , Antibacterianos/farmacologia , Enterotoxinas/genética , Humanos , Staphylococcus aureus Resistente à Meticilina/genética , Testes de Sensibilidade Microbiana , Leite , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/genética
4.
J Hazard Mater ; 439: 129588, 2022 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-35850070

RESUMO

In this study, seven different materials were analyzed and includes coffee grounds (CG), two types of cellulose (CGC and CC), two types of modified cellulose (CT and CTCD), and cross-linked ß-cyclodextrin (CD-1 and CD-2) were tested as adsorbents for the removal of dyes from the wastewater. The composition, morphology, and presence of functional groups in the obtained sorption materials were characterized by elemental analysis, SEM, TG/DTA, and FTIR spectroscopy. The sorption processes of the model contaminant, crystal violet (CV), were studied by kinetics and equilibrium models. The results showed, that using CTCD, the dye was adsorbed rapidly in 1 min and the slowest adsorption occurred in 20 min by CG. The time evolution was adjusted using a two-model, pseudo second-order model (CG and CGC) and pseudo first-order model in the rest adsorbents. According to the Langmuir and Sips isotherm models, the maximum adsorption capacities were very high in each case ranging from 1092.24 to 1220.40 mg g-1. Moreover, the adsorption capacity of the near-natural materials remained even higher after five regeneration cycles. The regeneration is almost waste-free and the materials used can be decomposed during composting. In addition, almost complete removal of cationic dyes was observed during the treatment of real wastewater samples.


Assuntos
Poluentes Químicos da Água , beta-Ciclodextrinas , Adsorção , Cátions , Celulose/química , Café , Corantes/química , Concentração de Íons de Hidrogênio , Cinética , Desenvolvimento Sustentável , Águas Residuárias/química , Poluentes Químicos da Água/química
5.
Molecules ; 27(12)2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35744937

RESUMO

Nowadays, algae are becoming more and more popular as a food group rich in nutrients, cosmetic raw materials full of antioxidants or valuable dietary supplements. They are of interest for the industry because they are found almost all over the world, in all climatic zones, both in fresh and salt waters. The aim of this study was to take a broad look at green algae (Chlorophyta) and to show how large the variability of the content of active compounds may depend on the species and the place and time of sample collection. Particular attention was paid to compounds with antioxidant activity, whose simplified profiles were created on the basis of complementary, semi-quantitative methods. Additionally, time-yield extraction optimizations were performed. Three different specimens of Ulva lactuca were compared: from the coastal zone of the Baltic Sea, from the open Baltic Sea area around Bornholm and Ulva spiralis (Ulva lactuca polymorph) from the Atlantic Ocean. The studied algae of the Cladophora genera were three different species of freshwater algae from various habitats: a lake (Cladophora glomerata), a river (Cladophora rivularis) and aquarium farming (Cladophora aegagropila, syn. Aegagropila linnaei). The content of antioxidants and the extraction efficiency varied significantly depending on the species.


Assuntos
Clorófitas , Alga Marinha , Ulva , Antioxidantes , Clorófitas/química , Ecossistema , Alga Marinha/química , Ulva/química , Água
6.
Sci Rep ; 11(1): 23883, 2021 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-34903798

RESUMO

Damask rose is a well-established, abundant source of phytochemicals, as well as economically important essential oil-however, its cultivation is demanding and costly. In this paper, extracts from four raw plant materials-Salvia officinalis, Sambucus nigra, Matricaria chamomilla, Calendula officinalis, known to be rich in phenolic compounds, but also far easier to cultivate-were directly compared to those obtained from Rosa × damascena Mill. By combining diverse extraction methodologies (in a Soxhlet apparatus, ultrawave-assisted and microwave-assisted, using supercritical CO2) and complementary in vitro assays (radical scavenging, iron reducing, Folin-Ciocalteau and Al3+ complexation), it was possible to conveniently approximate and compare the phytochemical portfolios of those diverse plants. By factoring in the crop yields of different species, economically important conclusions can be reached-with pot marigold (C. officinalis) seemingly the most viable substitute for damask rose as a source of phenolics. Fatty acid and microelement analyses were also performed, to further enrich the chemical profiles of plant extracts. The paper also aims to collate and redesign multiple colorimetric assays frequently used while studying plant extracts in vitro, but criticized for their lack of correlation to in vivo activity. We show that they remain a viable tool for direct comparison of extraction methodologies, while highlighting their shortcomings.

7.
Food Chem ; 358: 129827, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33933977

RESUMO

Surface active agents derived from the non-toxic sweetener sucralose and fatty acids of different chain length were synthesized. Obtained compounds were characterized chemically and with regard to their properties as emulsifying agents, antimicrobial preservatives and fat-soluble sweeteners. Results show that sucralose-fatty acid esters are possible multi-purpose additives, compatible with both cosmetic and edible emulsions, as well as purely oil-based, waterless formulations. Their relative effectiveness in those applications varies, and is highly dependent on the fatty acid chain length, with hydrophobic/hydrophilic character strongly impacting both emulsifying and antimicrobial properties. While the structural differences between sucrose and sucralose proved to be enough to push all of the newly synthesized compounds out of the detergent/solubilizer category of surfactants, the retention of the substrate's high sweetness is an indication that non-bitter compounds with washing capabilities are possible to obtain.


Assuntos
Sacarose/análogos & derivados , Tensoativos/química , Tensoativos/farmacologia , Edulcorantes/química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Caprilatos/química , Emulsificantes/química , Emulsões , Ésteres/química , Ácidos Graxos/química , Interações Hidrofóbicas e Hidrofílicas , Testes de Sensibilidade Microbiana , Solubilidade , Relação Estrutura-Atividade , Sacarose/química , Tensoativos/síntese química , Edulcorantes/síntese química , Paladar
8.
Materials (Basel) ; 13(14)2020 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-32664284

RESUMO

In this study, the classical Stöber silica synthesis protocol was used to test the limits of simplification in the preparation and size determination of nanoparticles. The scope of three-ingredient, one-pot synthesis was established in conditions of regular 96% and 99.8% ethanol as solvent, with aqueous ammonia as the only source of base and water. Particles with diameters in the 15-400 nm range can be reliably obtained with this straightforward approach, and the direct relationship between the size and the product of concentrations of water and ammonia is evidenced. Furthermore, the idea of a linear approximation for Mie scattering in particular conditions is discussed, using experimental data and theoretical calculations. A simple, fast method for particle size determination utilizing a UV-Vis spectrophotometer-an easily accessible instrument-is explained, and shows a level of error (<0.5 SD) that can be acceptable for less rigorous laboratory use of nanoparticles or serve as a quick means for testing the influence of minor alterations to known synthetic protocols. This work aims to show that nanoparticle synthesis can (and should) become a regular occurrence, even in non-specialized labs, facilitating research into their new applications and inspiring outside-the-box solutions, while discussing the drawbacks of a more relaxed synthetic regimen.

9.
Animals (Basel) ; 10(3)2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32192036

RESUMO

The aim of the study was to evaluate the effect of Spirulina platensis, formulation containing microalgal extract, post-extraction residue, and formulation without algal extract (containing only emulsifier) on the content of FAs in the eggs of laying hens. The experiment was conducted on 90 laying hens (ISA Brown) as a completely randomized design. Hens were assigned to five experimental groups (six replicates). The FAs content in eggs was determined after 30, 60, 90, and 120 days of the experiment. There were no statistically significant differences in FA profiles after 30 days of the experiment. It was shown that after 60, 90, and 120 days of the experiment, the investigated additives had a significant impact on the content of such acids as: dodecanoic acid (C12:0), C15:0, nonadecanoic acid (C19:0), myristoleic acid (C14:1 n-5), α-linolenic acid (ALA, C18:3 n-3), DPA, C20:2 n-6, and decosahexaenoic acid (DHA C22:6 n-6). There were also significant differences in total PUFA n-3, PUFA n-6, and n-6/n-3 ratio in eggs. The obtained results suggest that the use of algae extract and emulsifier in laying hens nutrition has the greatest impact on the FA profile in the eggs.

10.
Sci Rep ; 10(1): 646, 2020 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-31959807

RESUMO

In a more synthetical approach to the study of ion-specific phenomena, four dipodal bis(guanidinium) siloxanes have been synthesized starting from glycine, ß-alanine, γ-aminobutanoic acid, L-proline and 1,3-bis(3-aminopropyl)tetramethyldisiloxane. Together with their non-amide progenitor they were comparatively studied in regards to their interactions with nine different anions: sulphate, chromate, molybdate, benzoate, chloride, azide, nitrite, nitrate and thiocyanate. Their aqueous solubilities, form, 1H NMR and FT-IR spectra were examined while searching for anion-specific interactions falling in- or outside of the Hofmeister series. We show that although the "chao-" and "kosmotropic" ions affect the properties of solutions in a predictable way, more selective cation-anion pairing is responsible for phase separation and crystallinity. As a prominent example, crystal structure of one of the benzoate salts was successfully obtained and reveals a synergy of hydrophobic packing, ionic and hydrogen bonding. Immobilized but still flexible siloxane bridges give rise to crystals described by P 42/n space group and neatly segregated into hydro- and lipophilic sections.


Assuntos
Aminoácidos/química , Guanidina/síntese química , Íons/química , Silanos/síntese química , Ânions/química , Ácido Butírico/química , Cristalização , Glicina/química , Guanidina/química , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Prolina/química , Silanos/química , Solubilidade , Soluções , Relação Estrutura-Atividade , Água , beta-Alanina/química
11.
J Appl Phycol ; 30(1): 591-603, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29576688

RESUMO

The biologically active compounds (fatty acids, pigments, phenolics, and flavonoid content) were studied in supercritical fluid extracts from the biomass of marine (Ulva clathrata, Cladophora glomerata, Polysiphonia fucoides, and their multi-species mixture) and freshwater (C. glomerata) macroalgae. Different extraction techniques were used in order to compare differences in the biologically active compound composition of the macroalgal extracts. The results indicated that the saturated and unsaturated fatty acids ranged from C9:0 to C22:0. The analysis of differences in the composition of unsaturated to saturated fatty acids in extracts showed that palmitic acid (C16:0) and oleic acid (C18:1, n-9) reached the highest value not only in marine monospecies and multi-species biomass but also in the freshwater macroalga C. glomerata. When comparing the similarity between the concentration of fatty acids and the ratio of the concentration of unsaturated fatty acids to saturated in macroalgal extracts, we found small but not statistically significant variations in values between years (up to 10%). This is acceptable for applications as a stable raw material for industrial purposes. Significantly higher values of fatty acids, carotenoids, and chlorophylls were obtained in the case of SC-CO2 extraction. The active ingredients of polyphenols, possessing antioxidant activity ranged from approximately 2-4%. Moreover, flavonoids represented less than 10% of the total content of polyphenolic compounds. The extraction efficiency of polyphenols was higher from a mixture of marine algae for the ultrasound-assisted extraction compared to freshwater. All these findings show that marine and freshwater macroalgae, as a raw material, have the optimal biologically active compounds composition for cosmetics.

12.
Water Res ; 135: 66-74, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29454923

RESUMO

Polyphenols are chemicals that primarily inhibit the growth of various autotrophic organisms. The presence of these metabolites greatly boosts the ecological dominance of eg. Cladophora, which creates large surface mats. The main goal of our work was to quantify the phenol and polyphenols (allelopathic substances) secreted by the macroalgae as a result of exposure to biotic stress caused by competition. The research was carried out on the Cladophora glomerata biomass collected from two freshwater ecosystems located in Wielkopolska Region (Poland, Fig. 1): Oporzynskie Lake (N52° 55', E 17° 9') and Nielba River (N52˚48', E 17° 12'). Seasonal variability (May-October 2015) in the properties of C. glomerata mats in the river and lake ecosystem was also analyzed in relation to the physicochemical parameters of water. In addition, the content of pigments in the analyzed biomass was determined during the appearance of algae mats in water reservoirs. Biomass extraction was performed to determine the phenolic and carotenoid contents (chlorophyll and carotenoids) by using two extraction methods: microwave-assisted extraction (MAE) and supercritical fluid extraction (SFE). After isolation of the phenols from the thalli (mats) and the habitat, they were analyzed using the Folin-Ciocalteu method with some modifications, while the pigment content (chlorophyll and carotenoids) was evaluated by the spectrophotometric method Liechtenthaler (1987) with some variations. Analysis of the content of these components in algae extracts indicates that the tendency of changes in their contents was similar or the same. Growth and decrease of phenolic content (Cladophora T MAE and Cladophora T SFE) and pigments (MAE chlorophyll, SFE and MAE carotenoids) at the same time were independent of the insulation method used. The mats formed by C. glomerata on the surface of Lake Oporzynskie were more stable and larger surface area than those on the Nielba River, which could explain differences in polyphenol concentrations in these two aquatic ecosystems. The results suggest a reduction in the secretion of phenolic compounds with an aging population of algae.


Assuntos
Carotenoides/análise , Clorofila/análise , Clorófitas/química , Fenóis/análise , Biomassa , Fracionamento Químico/métodos , Ecossistema , Lagos/química , Micro-Ondas , Polônia , Polifenóis/análise , Estações do Ano , Alga Marinha/química
13.
Acta Pol Pharm ; 74(2): 633-641, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29624269

RESUMO

Marine algae are widely used as cosmetics raw materials. Likewise, freshwater alga Cladophora glomerata may be a good source of fatty acids and others bioactive agents. The aims of this study was to find out if the addition of the extract from the freshwater C. glonerata affects the stability of prepared cosmetic emulsions and to investigate in vivo effects of the extract in cosmetic formulations on hydration and elasticity of human skin. Extract from the freshwater C. glonierata was obtained using supercritical fluid extraction (SFE). Two forms of O/W emulsions were prepared: placebo and emulsion containing 0.5% of Cladophora SFE extract. The stability of obtained emulsions was investigated by using Turbiscan Lab Expert. Emulsions were applied by .volunteers daily. Corneometer was used to evaluate skin hydration and cutometer to examine skin elasticity. Measurements were conducted at reference point (week 0) and after 1st, 2nd, 3rd and 4th week of application. The addition of Cladophora extract insignificantly affected stability of the emulsion. The extract from C. glomerata in the emulsion influenced the improvement of both skin hydration and its elasticity. Thus, freshwater C. glonierata extract prepared via SFE method may be considered as an effective cosmetic raw material used as a moisturizing and firming agent.


Assuntos
Extratos Celulares/administração & dosagem , Extratos Celulares/química , Alga Marinha/química , Creme para a Pele/administração & dosagem , Creme para a Pele/química , Pele/efeitos dos fármacos , Administração Cutânea , Adulto , Água Corporal/metabolismo , Extratos Celulares/isolamento & purificação , Cromatografia com Fluido Supercrítico , Estabilidade de Medicamentos , Elasticidade , Emulsões , Humanos , Óleos/química , Pele/metabolismo , Fatores de Tempo , Água/química , Adulto Jovem
14.
PLoS One ; 10(12): e0145680, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26714187

RESUMO

Five novel disiloxane compounds comprising guanidinium and pyridinium moieties were obtained with high yields and purity. The verified synthetic pathways were then applied for modification of pre-functionalized silica gel, producing materials with the analogous organic side-chains. These halide-containing compounds and materials were then compared as to their ion-exchange properties: two disiloxanes proved to be effective in leaching different anions (nitrate, benzoate and ascorbate) from solid to organic phase, and pyridinium-functionalized silica gels showed selectivity towards perchlorate ion, removing it from methanolic solutions with preference to other singly charged anions. The results presented demonstrate that both compounds and materials containing silicon-carbon bonds can be produced using the same methodology, but offer strikingly different application opportunities. Comparison of their properties provides additional insight into the binding mode of different anions and hints at how the transition from a flexible siloxane bridge to immobilization on solid surface influences anion-binding selectivity. Additionally, one of the siloxane dipodands was found to form a crystalline and poorly soluble nitrate salt (1.316 g/L, water), although it was miscible with a wide range of solvents as a hydrochloride. A possible explanation is given with the help of semi-empirical calculations. A simple, time- and cost-efficient automated potentiometric titration methodology was used as a viable analytical tool for studying ion-exchange processes for both compounds and materials, in addition to standard NMR, FT-IR and ESI-MS methods.


Assuntos
Guanidina/química , Piridinas/química , Silanos/química , Sílica Gel/química , Troca Iônica , Modelos Moleculares , Conformação Molecular , Nitratos/química
15.
J Sci Food Agric ; 95(11): 2279-86, 2015 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-25298151

RESUMO

BACKGROUND: Mares' milk is becoming increasingly popular in Western Europe. This study was thus aimed at investigating the impact of stage of lactation and season on chemical composition, somatic cell count and some physicochemical parameters of mares' colostrum and milk, and at developing a method for the determination of vitamin C (ascorbic acid) in mares' milk and to determine its content in fresh and stored milk. RESULTS: The analysis conducted showed an effect of the stage of lactation on contents of selected chemical components and physicochemical parameters of mares' milk. In successive lactation periods levels of fat, cholesterol, energy value, citric acid and titratable acidity decreased, whereas levels of lactose and vitamin C, as well as the freezing point, increased. Analysis showed that milk produced in autumn (September, October, November) had a higher freezing point and lower concentrations of total solids, protein, fat, cholesterol, citric acid and energy value in comparison to milk produced in summer (June, July, August). Mares' milk was characterised by low somatic cell count throughout lactation. In terms of vitamin C stability the most advantageous method of milk storage was 6-month storage of lyophilised milk. CONCLUSION: In general, the results confirmed that mares' milk is a raw material with a unique chemical composition different from that produced by other farm animals.


Assuntos
Ácido Ascórbico/metabolismo , Armazenamento de Alimentos , Cavalos , Lactação/metabolismo , Leite/metabolismo , Valor Nutritivo , Estações do Ano , Animais , Contagem de Células , Colostro/metabolismo , Dieta , Europa (Continente) , Feminino , Liofilização , Congelamento , Humanos , Lactose/metabolismo , Gravidez , Vitaminas/metabolismo
16.
Ecotoxicology ; 22(3): 558-73, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23400796

RESUMO

The possibility of using freshwater Ulva (Chlorophyta) as a bioaccumulator of metals (Co, Cr, Cu, Mn and Zn) in lake and river water was examined weekly in the summer of 2010 in three types of samples: the water, the sediment and the thalli of Ulva. Samples of freshwater Ulva were collected from two aqueous ecosystems lie 250 km away from the basin of the Baltic Sea and 53 km from each other. A flow lake located in the centre of the big city was the first water reservoir (ten sites) and second, the suburban river (six sites). The mean metal concentrations in the Ulva tissue from the river and the lake decreased in the following order: Mn > Zn > Cr > Cu > Co and Mn > Cr > Zn > Cu > Co, respectively. Moreover, a negative and statistically significant correlation between Mn concentrations in the Ulva thalli and the river water was observed. Additionally, numerous correlations were noted between the different concentrations of metals within the Ulva thalli, in the water and in the sediment. The great concentrations of Mn and Zn and the smallest of Co were found in thalli of Ulva, irrespective of the type of the ecosystem from which samples of algal thalli originated. Freshwater Ulva populations examined in this study were clearly characterized a dozen or so times by the higher Mn and Cr accumulation than taxa from that genera coming from sea ecosystems. The calculated bioconcentration factor confirm the high potential for freshwater Ulva to be a bioaccumulator of trace metals in freshwater ecosystems.


Assuntos
Água Doce/química , Metais Pesados/metabolismo , Ulva/metabolismo , Poluentes Químicos da Água/metabolismo , Cromo/metabolismo , Cobalto/metabolismo , Cobre/metabolismo , Ecossistema , Monitoramento Ambiental , Sedimentos Geológicos/química , Lagos/química , Manganês/metabolismo , Rios/química , Estações do Ano , Zinco/metabolismo
17.
Chemosphere ; 89(9): 1066-76, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22726424

RESUMO

We analyzed the ability of freshwater taxa of the genus Ulva (Ulvaceae, Chlorophyta) to serve as bioindicators of metal in lakes and rivers. Changes in heavy metal (Ni, Cd and Pb) and alkaline earth metal (Ca and Mg) concentrations in freshwater Ulva thalli were investigated during the period from June to August 2010. The study was conducted in two ecosystems in Western Poland, the Malta lake (10 sites) and the Nielba river (six sites). Three components were collected for each sample, including water, sediment and Ulva thalli. The average concentrations of metals in the water sample and in the macroalgae decreased in the following order: Ca>Mg>Ni>Pb>Cd. The sediment revealed a slightly altered order: Ca>Mg>Pb>Ni>Cd. Ca and Mg were found at the highest concentrations in thalli due to the presence of carbonate on its surface. Among the examined heavy metals in thalli, Ni was in the highest concentration, and Cd found in the lowest concentration. There were statistically significant correlations between the levels of metals in macroalgae, water and sediment. Freshwater populations of Ulva exhibited a greater efficiency to bioaccumulate nickel as compared to species derived from marine ecosystems.


Assuntos
Monitoramento Ambiental/métodos , Metais Alcalinoterrosos/metabolismo , Metais Pesados/metabolismo , Ulva/metabolismo , Poluentes Químicos da Água/metabolismo , Água Doce
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