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1.
Int J Life Cycle Assess ; 28(3): 221-233, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36686846

RESUMO

Purpose: There is an increasing interest in the use of non-nutritive sweeteners to replace added sugar in food and beverage products for reasons of improving consumer health. Much work has been done to understand safety of sweeteners, but very little on sustainability. To address that gap, this study presents the results of a life cycle assessment (LCA) of production of rebaudioside A 60%, 95% pure (RA60) steviol glycoside mix from Stevia rebaudiana leaf grown in Europe. Methods: An attributional cradle-to-factory-gate life cycle assessment was conducted on growing of stevia leaves and extraction of steviol glycosides in Europe. Primary data were used from a case study supply chain. Results are reported in impact categories from the ReCiPe 2016 (H) method, with focus given to global warming potential, freshwater eutrophication, water consumption, and land use. Impacts are expressed both in terms of production mass and sweetness equivalence, a common metric for understanding high intensity sweetener potency. Sweetness equivalence of RA60 is typically 200 to 300 times that of sugar. Comparison of environmental impact is made to sugar (sucrose) produced from both cane and beets. The research is part of the EU project SWEET (sweeteners and sweetness enhancers: impact on health, obesity, safety, and sustainability). Results and discussion: Global warming potential for production of RA60 was found to be 20.25 kgCO2-eq/kgRA60 on a mass basis and 0.081 kgCO2-eq/kgSE on a sweetness equivalence basis. Field production of stevia leaves was found to be the main source of impact for most impact categories, and for all four focus categories. Extraction of the RA60 was the main source of impact for the others. Leaf processing and seedling propagation were minor contributors to life cycle impact. Removal of international transport from the supply chain reduced global warming potential by 18.8%. Compared with sugar on a sweetness equivalence basis, RA60 has approximately 5.7% to 10.2% the impact for global warming potential, 5.6% to 7.2% the impact for land use, and is lower across most other impact categories. Conclusion: This is the first LCA of steviol glycoside mix RA60 produced from leaf in Europe. The results indicate that RA60 can be used to reduce environmental impact of providing a sweet taste by replacing sugar across all impact categories. However, it is important to note that specific formulations in which RA60 is used will have a bearing on the final environmental impact of any food or beverage products. For solid foods, this requires further research. Supplementary Information: The online version contains supplementary material available at 10.1007/s11367-022-02127-9.

2.
Molecules ; 26(19)2021 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-34641549

RESUMO

In a cultural heritage context, fatty acids are usually found as breakdown products of lipid-containing organic remains in archaeological findings, binders in aged oil paintings, and additives in modern art-related materials. They may further interact with the ionic environment transforming into metal soaps, a process that has been recognized as a threat in aged paintings but has received less attention in archaeological objects. The investigation of the above related categories of materials with infrared spectroscopy can provide an overall picture of the organic components' identity and demonstrate their condition and prehistory. The capability of investigating and distinguishing fatty acids and their metal soaps through their rich infrared features, such as the acidic carbonyl, the carboxylate shifts, the variable splits of alkyl chain stretching, bending, twisting, wagging, and rocking vibrations, as well as the hydroxyl peak envelopes and acid dimer bands, allows for their direct detailed characterization. This paper reviews the infrared spectra of selected saturated fatty monoacids and diacids, and their corresponding sodium, calcium, and zinc salts and, supported by newly recorded data, highlights the significance of their spectroscopic features.

3.
Appl Spectrosc ; 72(10): 1511-1527, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29747520

RESUMO

The question for discriminating iron gall inks is addressed by correlating their infrared (IR) spectra in liquid and dried states with the materials used in their formulations and considering their possible interactions. A series of laboratory inks were prepared according to historic recipes, mainly found in 19th-century documents, and were accordingly studied using Fourier transform infrared (FT-IR) spectroscopy. All ink formulations were based on Aleppo galls, ferrous sulfate, and gum arabic at variable proportions, with various added components, such as alum, vinegar, glycerol, sugar, silver nitrate, cloves, and white wine. Ingredients of the corresponding inks were recognized by means of their IR fingerprints in both their liquid and dried states, respectively. Although a few inks of distinct formulations showed discernible differences in their spectra, the majority showed quite similar absorptions. Principal component analysis and discriminant analysis were employed to successfully discriminate inks, based on their IR peaks. Spectra recorded in the liquid state, despite their broad absorption features, led to satisfactory discrimination of certain types of inks as most of their ingredients are reflected in their IR peaks. Spectra from dried inks contained similar information, which equally worked in a sufficient discriminatory way. Key IR peaks in the recorded spectra of inks made with the addition of special ingredients, such as vinegar, wine, alum, glycerol, and sugar, as well as those prepared with specific tannin-enhancing procedures, such as gall boiling, were located and used in the discrimination basis.

4.
Pharmacogenomics J ; 14(6): 523-5, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24889923

RESUMO

Psoriasis affects 2-3% of the population, causing significant morbidity and financial burden. Immunosuppressive drugs such as cyclosporine are first line systemic therapies for moderate-to-severe forms. However, patients exhibit heterogeneity in their response to therapy, possibly due to genetic factors. The aim of the present study was to assess the ABCB1 T-129C, G1199A, C1236T, G2677T and C3435T single-nucleotide polymorphisms (SNPs) as candidate predictive markers of response to cyclosporine treatment in 84 psoriasis patients. 62% of the patients were defined as responders and 38% as nonresponders. All SNPs complied with Hardy-Weinberg equilibrium. SNP and haplotype analyses were performed to access responsiveness to treatment. Association analysis revealed statistically significant association of SNP 3435 T with negative response (P=0.0075), a result that was further validated in haplotype analysis. This study is the first in the field of the pharmacogenetics of cyclosporine in psoriasis whose results merit further exploitation in larger independent cohorts.


Assuntos
Ciclosporina/uso terapêutico , Polimorfismo de Nucleotídeo Único/genética , Psoríase/tratamento farmacológico , Psoríase/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Adulto , Feminino , Grécia , Humanos , Masculino , Psoríase/metabolismo
5.
Appl Spectrosc ; 66(5): 580-90, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22524964

RESUMO

An ethylene-methacrylic acid copolymer, formulated by BASF as a waterborne suspension of its alkylammonium salt and used, among other applications, in art conservation as a temporary protective coating was characterized using Fourier transform infrared (FT-IR) spectroscopy aided by modulated differential scanning calorimetry (MDSC) and ellipsometry. The thermal conversion of thin copolymer films from the freshly applied state, where carboxylic acid and carboxylate ion functional groups co-exist, to a purely acidic working state was spectroscopically followed. Transmission mid-infrared data of the working state showed a 1 : 12 ratio of methacrylic acid towards ethylene units. The glass transition temperature (T(g)) in the same state was found at 45 °C. Copolymer films spin-coated on mechanically polished bronze and iron coupons were characterized with transflection infrared spectroscopy and compared to corresponding transmission mid-infrared spectra of copolymer films spin-coated on silicon wafers. In the case of bronze coupons, evidence for interaction of the carboxylate ion with the copper substrate was obtained. The chemical structure and the thermal behavior of the coating, as well as some implications on its protective capability towards iron and copper alloys, is discussed as this material has received considerable attention in the field of metal conservation and coatings.

6.
Bull Entomol Res ; 102(3): 325-32, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22112675

RESUMO

A dual cytogenetic and molecular analysis was performed in four species of Cyclocepala (Coleoptera: Scarabaeidae: Dynastinae) from Lesser Antilles (Martinique, Dominica and Guadeloupe). Two species/sub-species, C. mafaffa grandis and C. insulicola, are endemic to Guadeloupe. They have their own non-polymorphic karyotype and a fairly homogeneous haplotype of the COI gene. C. melanocephala rubiginosa has a distinct karyotype. Its COI haplotype is homogeneous in Guadeloupe and heterogeneous in Martinique. Finally, C. tridentata has highly different karyotypes and haplotypes in the three islands. In Martinique, its karyotype, composed of metacentrics, is monomorphic while its haplotype is fairly heterogeneous. Both are close to those of other Cyclocephala and Dynastinae species, thus fairly ancestral. In Guadeloupe, its karyotype is highly polymorphic, with many acrocentrics, and its haplotype fairly homogeneous. Both are highly derived. In Dominica, both the karyotype and the haplotype represent intermediate stages between those of Martinique and Guadeloupe. We conclude that several independent colonization episodes have occurred, which excludes that C. insulicola is a vicariant form of C. tridentata in Guadeloupe. Both chromosome and COI gene polymorphisms clearly indicate a recent colonization with a northward direction for C. tridentata.


Assuntos
Evolução Biológica , Besouros/genética , Animais , Cromossomos , Fluxo Gênico , Masculino , Análise de Sequência de DNA , Índias Ocidentais
7.
Bull Entomol Res ; 101(3): 345-52, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21208509

RESUMO

In cockchafers of the genus Melolontha, there is a marked intraspecific polymorphism for morphological characters, making some specimens of one species resemble another. A cytogenetic and molecular (mitochondrial COI gene sequence) study of typical and atypical forms of M. melolontha and M. hippocastani, captured at the same period and area, was performed. Karyotypes and haplotypes clearly characterize each taxon, placing atypical specimens in one or the other species unambiguously. This formally discards the role of hybridization in phenotypic resemblance, as usually proposed. Karyotypes and haplotypes were compared to those of M. pectoralis and Phyllophaga pleei, a more distantly related Melolonthinae, and some Dynastinae species, to reconstruct their ancestral karyotype. The karyotype of M. melolontha is the most derivative and that of P. pleei the most conserved among the Melolonthinae studied, which fits with the phylogeny established by COI gene analysis. Both karyotypes and COI haplotypes demonstrate the proximity of M. pectoralis and M. melolontha. The karyotype of M. melolontha is polymorphic, without relationship with morphological variations. Finally, the existence of similar morphological variations in different Melolontha species and chromosomal polymorphism in M. melolontha is discussed in relation with a network (reticulated) mode of speciation.


Assuntos
Evolução Biológica , Cromossomos/genética , Besouros/anatomia & histologia , Besouros/genética , Variação Genética , Fenótipo , Animais , Sequência de Bases , Primers do DNA/genética , DNA Mitocondrial/genética , França , Haplótipos/genética , Cariotipagem , Funções Verossimilhança , Modelos Genéticos , Dados de Sequência Molecular , Análise de Sequência de DNA , Especificidade da Espécie
8.
Mol Ecol ; 18(22): 4631-49, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19845856

RESUMO

The major histocompatability complex (MHC) is a multigene family of receptors that bind and present antigenic peptides to T-cells. Genes of the MHC are characterized by an outstanding genetic polymorphism, which is considered to be maintained by positive selection. Sites involved in peptide binding form binding pockets (P) that are collectively termed the peptide-binding region (PBR). In this study, we examined the level of MHC genetic diversity within and among natural populations of brown hare (Lepus europaeus) from Europe and Anatolia choosing for analysis of the second exon of the DQA locus, one of the most polymorphic class II loci. We aimed at an integrated population genetic analysis of L. europeaus by (i) correlating MHC polymorphism to genetic variability and phylogenetic status estimated previously from maternally (mtDNA) and biparentally (allozymes, microsatellites) inherited loci; and (ii) comparing full-length exon amino acid polymorphism with functional polymorphism in the PBR and the binding pockets P1, P6 and P9. A substantial level of DQA exon 2 polymorphism was detected with two completely different set of alleles between the Anatolian and European populations. However, the phylogeny of full-length exon 2 Leeu-DQA alleles did not show a strong phylogeographic signal. The presence of balancing selection was supported by a statistically significant excess of nonsynonymous substitutions over synonymous in the PBR and a trans-species pattern of evolution detected after phylogenetic reconstruction. The differentiating patterns detected between genetic and functional polymorphism, i.e. the number and the distribution of pocket variants within and among populations, indicated a hierarchical action of selection pressures.


Assuntos
Genes MHC da Classe II , Genética Populacional , Lebres/genética , Polimorfismo Conformacional de Fita Simples , Alelos , Sequência de Aminoácidos , Animais , Sequência de Bases , DNA Mitocondrial/genética , Europa (Continente) , Evolução Molecular , Éxons , Frequência do Gene , Geografia , Repetições de Microssatélites , Dados de Sequência Molecular , Filogenia , Seleção Genética , Alinhamento de Sequência , Análise de Sequência de DNA
9.
Appl Spectrosc ; 61(10): 1045-51, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17958953

RESUMO

The depth-profiles of accelerated aged triterpenoid dammar and mastic varnishes, which had been uncovered by optimized KrF excimer laser ablation (248 nm, 25 ns), were examined by ultraviolet-visible (UV/VIS) spectrophotometry and attenuated total reflection (ATR) Fourier transform infrared (FT-IR) spectroscopy. The results reflect both the optical properties at the bulk (UV/VIS) and the surface (ATR/FT-IR) and establish the presence of degradation gradients across the depth of the degraded natural resin films. It is demonstrated that the UV part of the ambient radiation is absorbed by the deteriorated surface and that the optical densities of the aged varnish decrease as a function of depth. The absorbed UV wavelengths at the surface and the depth-wise reduction of light intensity result in a depth-dependent decrease in carbonyl absorbance and an increase in C-H bending vibration modes of methylene species pointing to structural modification in the triterpenoid mixture across depth.


Assuntos
Teste de Materiais/métodos , Pintura/análise , Espectrofotometria Ultravioleta/métodos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Triterpenos/química , Propriedades de Superfície , Triterpenos/análise
10.
Mol Ecol ; 13(6): 1377-90, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15140084

RESUMO

Analysis of the genetic structure of the Norway lobster (Nephrops norvegicus), a marine crustacean with high commercial value, was undertaken to gain information regarding the differentiation of Atlantic from Mediterranean populations of marine invertebrates. Restriction fragment length polymorphism analysis of two mitochondrial DNA segments, 3.6 kilobases in total, was performed. Twelve populations from the North Sea, Irish Sea, Portuguese coast and Aegean Sea were analysed. Low levels of differentiation were found among them (F(ST) = 0.018, P < 0.001) and there were no signs of an Atlantic-Mediterranean divide or of an isolation-by-distance scheme of differentiation. Possible reasons for these low levels of differentiation can be found in the recent expansion of N. norvegicus populations. This is supported by the mismatch distribution of pairwise haplotype differences, as well as by the high mean haplotype diversity (h = 0.93) combined with medium nucleotide diversity (pi = 0.0057) (in comparison to values for marine crustaceans or teleosts) found in this study. This combination of high levels of haplotype diversity with moderate to low levels of nucleotide diversity has also been frequently attributed to a recent time of divergence for various marine species. No evidence was found for a Mediterranean refugium during glaciation periods, separate from the Atlantic, as has been reported for some marine species. The Irish Sea population was the most differentiated as a result of reduced levels of diversity. Results are also discussed in the light of future management of N. norvegicus stocks.


Assuntos
DNA Mitocondrial/genética , Variação Genética , Genética Populacional , Nephropidae/genética , Filogenia , Análise de Variância , Animais , Oceano Atlântico , Análise por Conglomerados , Primers do DNA , Demografia , Geografia , Haplótipos/genética , Polimorfismo de Fragmento de Restrição , Dinâmica Populacional
11.
Bull Entomol Res ; 93(5): 447-53, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14641983

RESUMO

Random amplified polymorphic DNA (RAPD) analysis was applied to 120 individuals of Marchalina hellenica (Gennadius) representing six populations collected in northern, central and southern mainland Greece. One population was sampled on one species of fir tree and the others on two species of pine trees. Four random decamer primers were used to evaluate genetic variation among the populations examined. The results revealed intra- and interpopulation polymorphism both related to host type and region of origin. Phylogenetic analysis based on genetic distances estimated by the RAPD frequencies revealed an important genetic differentiation in samples collected on fir trees in southern Greece and to a lesser extent in samples from pine trees in central and northern Greece. Furthermore, considerable subdivision and restricted gene flow among the populations examined were observed. The results are discussed in relation to the biology and geographical distribution of M. hellenica in Greece.


Assuntos
Variação Genética , Hemípteros/genética , Árvores/parasitologia , Animais , Feminino , Genética Populacional , Grécia , Interações Hospedeiro-Parasita , Masculino , Polimorfismo Genético , Técnica de Amplificação ao Acaso de DNA Polimórfico/veterinária , Especificidade da Espécie
12.
Bull Entomol Res ; 93(6): 507-14, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14704097

RESUMO

The separation of the closely related predatory species Macrolophus melanotoma Costa (= M. caliginosus Wagner) and Macrolophus pygmaeus (Rambur) based exclusively on the different colour pattern of the first antennal segment (white central band in M. melanotoma and entirely black in M. pygmaeus) is rather precarious and their taxonomic status is still in doubt. In the present study their taxonomic status was evaluated by DNA confirmatory analysis and hybridization experiments between M. pygmaeus and a Macrolophus taxon, resembling M. melanotoma, with a first antennal segment entirely black or with a white central band collected from Dittrichia viscosa (L.) W. Greuter (Asteraceae) in southern Greece. Adult females from Dittrichia plants hybridized with males of M. pygmaeus and vice versa did not produce viable eggs. The Macrolophus species from Dittrichia irrespective of the first antennal segment coloration differed from M. pygmaeusin digestive patterns generated by AseI, XbaI, and MseI on 16S rRNA and in RAPD profiles produced by the primers OPA-18 and OPA-20. These results demonstrate that on Dittrichia plants there is a distinct dimorphic taxon, M. melanotoma, as it is the only species of the genus Macrolophus bearing a first antennal segment with a central white band. Given the limitation of the coloration pattern, the mtDNA genetic markers are the appropriate method for the identification of M. melanotomaand M. pygmaeus.


Assuntos
DNA Mitocondrial/análise , Hemípteros/classificação , Controle Biológico de Vetores , Animais , Feminino , Hemípteros/anatomia & histologia , Hemípteros/genética , Masculino , Filogenia , Reprodução , Estações do Ano , Especificidade da Espécie
13.
In Vivo ; 15(1): 49-52, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11286129

RESUMO

Proteins that bind and protect nucleic acids from acid precipitation have been characterized from human and mouse plasma. In the present study, one protein from Mendole (Spicara maena) eggs was purified to homogeneity, by means of acetone fractionation and Sephadex G-100 gel filtration. The protein inhibited DNA replication, exerted by various DNA polymerases. Amino-acid sequence analysis in the amino terminus revealed a unique sequence. Its possible physiological role is discussed.


Assuntos
Replicação do DNA/efeitos dos fármacos , Proteínas de Ligação a DNA/isolamento & purificação , Proteínas de Ligação a DNA/farmacologia , Óvulo/química , Ácidos , Sequência de Aminoácidos , Animais , Fracionamento Celular , Precipitação Química , Proteínas de Ligação a DNA/química , Dados de Sequência Molecular , Ácidos Nucleicos/isolamento & purificação , Oncorhynchus mykiss , Perciformes
14.
Mar Biotechnol (NY) ; 3(3): 264-74, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-14961364

RESUMO

The genetic differentiation of striped red mullet (Mullus surmuletus) and red mullet (Mullus barbatus) was investigated in 6 Mediterranean populations of each species by means of restriction fragment length polymorphism analysis of mitochondrial DNA. Three segments amplified by polymerase chain reaction (control region, COI, and 12S-16S ribosomal RNA) were digested with 20 restriction endonucleases, revealing 71 haplotypes for M. surmuletus and 30 for M. barbatus. For the two species nucleotide diversity was equally distributed within and among populations, leading to N(ST) values of 0.545 and 0.500 for M. surmuletus and M. barbatus, respectively. However, intrapopulation and interpopulation genetic structuring appeared to be much higher for M. surmuletus than for M. barbatus (1.88% vs. 0.46% of mean intrapopulation nucleotide diversity; 1.94% vs. 0.47% of mean interpopulation nucleotide diversity; 0.055% vs. 0.002% of net interpopulation divergence). Furthermore, 81.69% of the haplotypes observed for M. surmuletus were unique, whereas 70.29% of M. barbatus individuals were grouped in 3 common haplotypes. Given that fishing pressure and population sizes are similar for both species, this differentiation could be attributed to differences in biological parameters and life histories between the two species, coupled with oceanographic conditions prevailing in the studied area.

15.
Heredity (Edinb) ; 83 (Pt 1): 30-8, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10447700

RESUMO

Allozyme analysis on 20 putative enzyme-coding loci and RAPD analysis on 154 markers, amplified by eight decamer random primers, were used to assess the genetic variation of striped red mullet, Mullus surmuletus L., collected from six locations in the Mediterranean Sea. Both methods were able to detect a high degree of genetic polymorphism. For both methods, estimates of variance of allele frequencies (FST), and chi2 analyses, revealed significant differences (P < 0.05) among samples. Nei's genetic distance (D) among samples was low (mean D=0.011 for allozymes; mean D=0.018 for RAPDs) with data from both approaches revealing the sample from France to be most distinct from the Greek samples. Nevertheless, although most of the genetic variation in allozymes was not correlated with geographical distance, a correlation between genetic affinities and geographical area was found with RAPDs. It seems therefore that the RAPD method showed a more pronounced effect of isolation-by-distance in comparison with allozymes, probably because of the different number of markers of the red mullet genome examined with each method. Overall, the RAPD technique can be introduced as a complementary tool in the population genetics of marine fishes, providing supplementary information in their genetic stock structure analysis.

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