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1.
Parasit Vectors ; 14(1): 42, 2021 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-33430963

RESUMO

BACKGROUND: Novel malaria vector control approaches aim to combine tools for maximum protection. This study aimed to evaluate novel and re-evaluate existing putative repellent 'push' and attractive 'pull' components for manipulating the odour orientation of malaria vectors in the peri-domestic space. METHODS: Anopheles arabiensis outdoor human landing catches and trap comparisons were implemented in large semi-field systems to (i) test the efficacy of Citriodiol® or transfluthrin-treated fabric strips positioned in house eave gaps as push components for preventing bites; (ii) understand the efficacy of MB5-baited Suna-traps in attracting vectors in the presence of a human being; (iii) assess 2-butanone as a CO2 replacement for trapping; (iv) determine the protection provided by a full push-pull set up. The air concentrations of the chemical constituents of the push-pull set-up were quantified. RESULTS: Microencapsulated Citriodiol® eave strips did not provide outdoor protection against host-seeking An. arabiensis. Transfluthrin-treated strips reduced the odds of a mosquito landing on the human volunteer (OR 0.17; 95% CI 0.12-0.23). This impact was lower (OR 0.59; 95% CI 0.52-0.66) during the push-pull experiment, which was associated with low nighttime temperatures likely affecting the transfluthrin vaporisation. The MB5-baited Suna trap supplemented with CO2 attracted only a third of the released mosquitoes in the absence of a human being; however, with a human volunteer in the same system, the trap caught < 1% of all released mosquitoes. The volunteer consistently attracted over two-thirds of all mosquitoes released. This was the case in the absence ('pull' only) and in the presence of a spatial repellent ('push-pull'), indicating that in its current configuration the tested 'pull' does not provide a valuable addition to a spatial repellent. The chemical 2-butanone was ineffective in replacing CO2. Transfluthrin was detectable in the air space but with a strong linear reduction in concentrations over 5 m from release. The MB5 constituent chemicals were only irregularly detected, potentially suggesting insufficient release and concentration in the air for attraction. CONCLUSION: This step-by-step evaluation of the selected 'push' and 'pull' components led to a better understanding of their ability to affect host-seeking behaviours of the malaria vector An. arabiensis in the peri-domestic space and helps to gauge the impact such tools would have when used in the field for monitoring or control.


Assuntos
Comportamento Animal/efeitos dos fármacos , Repelentes de Insetos/normas , Malária/prevenção & controle , Controle de Mosquitos/métodos , Controle de Mosquitos/normas , Mosquitos Vetores/efeitos dos fármacos , Agricultura , Animais , Anopheles/efeitos dos fármacos , Anopheles/parasitologia , Ciclopropanos/farmacologia , Feminino , Fluorbenzenos/farmacologia , Habitação , Humanos , Mordeduras e Picadas de Insetos/prevenção & controle , Repelentes de Insetos/análise , Malária/transmissão , Mosquitos Vetores/parasitologia , Extratos Vegetais/farmacologia , Têxteis/análise
2.
Anal Chem ; 92(12): 8591-8598, 2020 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-32501709

RESUMO

The collection of solid particulates and liquids from surfaces by the use of cloth swipes is fairly ubiquitous. In such methods, there is a continuous concern regarding the ability to locate and quantitatively sample the analyte species from the material. In this effort, we demonstrate the initial coupling of an Advion Plate Express plate reader to a liquid sampling-atmospheric pressure glow discharge (LS-APGD) microplasma ionization source with an Orbitrap mass spectrometer to perform uranium isotopic analyses of solution residues on cotton swipes. The Plate Express employs a sampling probe head to engage and seal against the swipe surface. Subsequentially, the analyte residues are desorbed and transported within a 2% HNO3 electrolyte flow to the ionization source. Quantitative recoveries were observed following a single 30 s extraction step, with the absolute mass sampled per extraction being ∼100 ng. While the intrasample variability in the analytical responses for triplicate sampling of the same swipe yield ∼30% RSD, this lack of precision is offset by the ability to determine isotope ratios for enriched uranium specimens with a precision of better than 10% RSD. Pooled, intersample precision (n = 9) was found to be <5%RSD across the various sample compositions. Finally, 235U/238U determinations (ranging from 0.053 to 1.806) were accurate with errors of <10%, absolute. The 234U- and 236U-inclusive ratios were determined with similar accuracy in enriched samples. While the driving force for the effort is in the realm of nuclear nonproliferation efforts, the ubiquitous use of cloth swipes across many application areas could benefit from this convenient approach, including the use of versatile, reduced-format mass spectrometer systems.


Assuntos
Gossypium/química , Têxteis/análise , Urânio/análise , Pressão Atmosférica , Espectrometria de Massas
3.
Sci Rep ; 10(1): 4889, 2020 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-32273518

RESUMO

Neanderthals are often considered as less technologically advanced than modern humans. However, we typically only find faunal remains or stone tools at Paleolithic sites. Perishable materials, comprising the vast majority of material culture items, are typically missing. Individual twisted fibres on stone tools from the Abri du Maras led to the hypothesis of Neanderthal string production in the past, but conclusive evidence was lacking. Here we show direct evidence of fibre technology in the form of a 3-ply cord fragment made from inner bark fibres on a stone tool recovered in situ from the same site. Twisted fibres provide the basis for clothing, rope, bags, nets, mats, boats, etc. which, once discovered, would have become an indispensable part of daily life. Understanding and use of twisted fibres implies the use of complex multi-component technology as well as a mathematical understanding of pairs, sets, and numbers. Added to recent evidence of birch bark tar, art, and shell beads, the idea that Neanderthals were cognitively inferior to modern humans is becoming increasingly untenable.


Assuntos
Cognição , Fósseis , Homem de Neandertal/psicologia , Tecnologia/história , Têxteis/história , Animais , Arqueologia , Celulose/análise , França , História Antiga , Lignina/análise , Microscopia Eletrônica de Varredura , Solo/química , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Têxteis/análise
4.
Environ Health Perspect ; 127(11): 117004, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31774309

RESUMO

BACKGROUND: Newborns in neonatal intensive care units (NICUs) are in contact with a variety of medical products whose production might include synthetic chemicals with hormonal activity. OBJECTIVES: Our aim was to assess the content of bisphenol A (BPA) and parabens (PBs) and the hormone-like activities of a subset of medical products commonly used in NICUs in prolonged intimate contact with NICU newborns. METHODS: Fifty-two NICU items were analyzed, determining the concentrations of BPA and PBs [methyl- (MeP), ethyl- (EtP), propyl- (PrP), and butylparaben (BuP)] and using the E-Screen and PALM-luciferase assays to measure the in vitro (anti-)estrogenic and (anti-)androgenic activity, respectively, of the extracts. Items found to have elevated BPA/PB content or hormone-like activities were further extracted using leaching methodologies. RESULTS: BPA was found in three-fifths and PBs in four-fifths of tested NICU items, and ∼25% and ∼10% of extracts evidenced estrogenic and anti-androgenic activity, respectively. The highest BPA content was found in the three-way stopcock (>7.000 ng/g), followed by patterned transparent film dressing, gastro-duodenal feeding tubes, sterile gloves, single-lumen umbilical catheters, and intravenous (IV) infusion extension sets (concentrations ranged from 100 to 700 ng/g BPA). A total PB concentration (∑PBs) >100 ng/g was observed in several items, including light therapy protection glasses, patterned transparent film dressing, winged IV catheters, IV infusion extension sets, and textile tape. The highest estrogenic activity [>450 pM estradiol equivalent (E2eq)] was found in small dummy nipples, three-way stopcocks, and patterned transparent film dressing and the highest anti-androgenic activity [>5 mM procymidone equivalent units per gram (Proceq/g)] in small dummy nipples and three-way stopcocks. DISCUSSION: According to these findings, neonates might be exposed to multiple sources of BPA and PBs in NICUs via inhalation, dermal, oral, and IV/parenteral routes. There is a need to address the future health implications for these extremely vulnerable patients and to adopt precautionary preventive measures as a matter of urgency. https://doi.org/10.1289/EHP5564.


Assuntos
Compostos Benzidrílicos/análise , Exposição Ambiental/análise , Unidades de Terapia Intensiva Neonatal , Parabenos/análise , Fenóis/análise , Suplementos Nutricionais/análise , Equipamentos e Provisões , Humanos , Recém-Nascido , Pomadas/análise , Têxteis/análise
5.
J Control Release ; 285: 81-95, 2018 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-30008373

RESUMO

The use of fragrances is often essential to create an elegant, welcoming, or exhilarating environment. Through encapsulation, the release and delivery of fragrances are customized in many consumer products. For such purposes, cost-effective techniques have been developed and employed with the use of various polymers and porous organic materials to efficiently impart fragrances to foods and various other consumer products. After entrapment or uptake/storage of fragrant molecules within a polymeric complex, the properties can be investigated by automated thermal desorption (ATD) analysis. For efficient delivery, fragrances are adsorbed (or entrapped) in some media (e.g., fabric or paper). The release of such entrapped fragrances usually is achieved by spraying. Fragrances can be also loaded in a media by purging aroma gases or by adding fragrance essence directly into a liquid medium. Porous materials, such as zeolites, have been traditionally used for air purification as well as in cosmetics and similar applications. Similarly, other polymeric porous complexes have also been used in fragrance delivery as a templating agent for aromatherapy textiles. Such polymeric materials offer an advantage in terms of development of new hybrid blends via homogenous mixing of two or more matrices. Such blends may possess different desirable physical properties as encapsulants. This review article is aimed at presenting an overview of polymers and their complexes as the main media of fragrance encapsulation. This study also discusses the expansion and future application of porous materials as host matrices for fragrances.


Assuntos
Portadores de Fármacos/química , Composição de Medicamentos/métodos , Excipientes/química , Perfumes/administração & dosagem , Polímeros/química , Animais , Aromaterapia , Materiais Biocompatíveis/química , Cápsulas/química , Cosméticos/administração & dosagem , Humanos , Odorantes/análise , Porosidade , Têxteis/análise
6.
Int J Biol Macromol ; 117: 25-29, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-29800672

RESUMO

Skin protection and control of its microbial pathogens are highly important demands; natural biological agents are the ideals for that. Collagen (Cg) was extracted and characterized from skin and scales of Nile tilapia fish (Oreochromis niloticus), chitosan (Cts) was extracted from shrimp shells and extract of oak (Quercus infectoria) galls (OGE) was prepared. The antimicrobial potentialities of extracted agents, Cts and OGE, were qualitatively proved against skin pathogens, Staphylococcus aureus and Candida albicans, including both antibiotic sensitive and resistant strains, neither Cg nor negative control exhibited antimicrobial actions toward examined strain. The entire agents were loaded onto cotton fabrics and evaluated for antimicrobial actions and durability. Loaded textiles with the combined extracts' composite were the most effectual followed by individual treatments with OGE and Cts, respectively. Treated textiles upheld most of their antimicrobial activity after 2 laundering cycles toward all microbial pathogens. This invention could be consequently applied for production of skin protectant and hygienic fabrics.


Assuntos
Anti-Infecciosos , Quitosana , Colágeno , Proteínas de Peixes , Extratos Vegetais , Quercus/química , Têxteis , Animais , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Quitosana/química , Colágeno/química , Desinfetantes/química , Desinfetantes/farmacologia , Proteínas de Peixes/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Pele/microbiologia , Espectroscopia de Infravermelho com Transformada de Fourier , Têxteis/análise
7.
Nat Prod Res ; 32(3): 308-315, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28748727

RESUMO

This study analysed the use of sophora flower bud extract for dyeing and the resulting colour character and fastness of dyed silk fabric. The pigment composition on the silk fabric and recycling of this extract were also studied. The results indicated that the dyed silk fabric possessed good washing, rubbing and perspiration fastness, and the pigment composition on the silk fabric was mainly rutin and quercetin. The average recovery rate of the dye was 55.00%. These results demonstrate that the sophora flower bud extract is an effective natural dye.


Assuntos
Corantes/química , Extratos Vegetais/química , Seda/química , Sophora/química , Têxteis , Precipitação Química , Cromatografia Líquida de Alta Pressão , Corantes/análise , Flores/química , Espectroscopia de Ressonância Magnética , Extratos Vegetais/análise , Quercetina/análise , Rutina/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Têxteis/análise
8.
J Microencapsul ; 34(8): 722-731, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29105520

RESUMO

Anal fissure is common and painful disease of anorectum. In this study, microparticles containing nifedipine and lidocaine HCl were prepared by spray drying and applied to bio-degradable and bio-stable tampons. Characterization of microparticles was determined by visual analyses, mass yield, particle size measurement, encapsulation efficiency, drug loading and in vitro drug release. Mass yield was between 5.5 and 45.9%. The particle size was between 15.1 and 26.8 µm. Encapsulation efficiency were 96.142 ± 5.931 and 85.571 ± 3.301; drug loading were 65.261 ± 3.914% and 37.844 ± 4.339% of L2 and N1, respectively. Well-separated, mainly spherical microparticles with suitable properties were obtained. Optimum microparticles were applied to tampons. Physical properties and visual characteristics of tampons were investigated before and after binder application. In vitro drug release from tampons were also examined. According to the results, textile-based carrier systems loaded microparticles containing nifedipine and lidocaine HCl will be an effective and promising alternative for current anal fissure treatment.


Assuntos
Anestésicos Locais/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Fissura Anal/tratamento farmacológico , Lidocaína/administração & dosagem , Nifedipino/administração & dosagem , Tampões Cirúrgicos , Vasodilatadores/administração & dosagem , Alginatos/química , Anestésicos Locais/farmacocinética , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Humanos , Lidocaína/farmacocinética , Nifedipino/farmacocinética , Têxteis/análise , Vasodilatadores/farmacocinética
9.
J Chromatogr A ; 1487: 36-46, 2017 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-28131591

RESUMO

Madder (Rubia tinctorum L.) has been widely used as a red dye throughout history. Acid-sensitive colorants present in madder, such as glycosides (lucidin primeveroside, ruberythric acid, galiosin) and sensitive aglycons (lucidin), are degraded in the textile back extraction process; in previous literature these sensitive molecules are either absent or present in only low concentrations due to the use of acid in typical textile back extraction processes. Anthraquinone aglycons alizarin and purpurin are usually identified in analysis following harsh back extraction methods, such those using solvent mixtures with concentrated hydrochloric acid at high temperatures. Use of softer extraction techniques potentially allows for dye components present in madder to be extracted without degradation, which can potentially provide more information about the original dye profile, which varies significantly between madder varieties, species and dyeing technique. Herein, a softer extraction method involving aqueous glucose solution was developed and compared to other back extraction techniques on wool dyed with root extract from different varieties of Rubia tinctorum. Efficiencies of the extraction methods were analysed by HPLC coupled with diode array detection. Acidic literature methods were evaluated and they generally caused hydrolysis and degradation of the dye components, with alizarin, lucidin, and purpurin being the main compounds extracted. In contrast, extraction in aqueous glucose solution provides a highly effective method for extraction of madder dyed wool and is shown to efficiently extract lucidin primeveroside and ruberythric acid without causing hydrolysis and also extract aglycons that are present due to hydrolysis during processing of the plant material. Glucose solution is a favourable extraction medium due to its ability to form extensive hydrogen bonding with glycosides present in madder, and displace them from the fibre. This new glucose method offers an efficient process that preserves these sensitive molecules and is a step-change in analysis of madder dyed textiles as it can provide further information about historical dye preparation and dyeing processes that current methods cannot. The method also efficiently extracts glycosides in artificially aged samples, making it applicable for museum textile artefacts.


Assuntos
Técnicas de Química Analítica/métodos , Corantes/análise , Glucose/química , Rubia/química , Animais , Antraquinonas/análise , Técnicas de Química Analítica/normas , Cromatografia Líquida de Alta Pressão , Corantes/química , Glicosídeos/química , Hidrólise , Extratos Vegetais/análise , Raízes de Plantas/química , Têxteis/análise
10.
Anal Sci ; 31(12): 1317-23, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26656824

RESUMO

The identification of ancient silk is of great importance in both archaeology and academia. In the present work, a specific antibody having the characteristics of low cost, easy operation and extensive applicability was developed directly through immunizing rabbits with complete antigen (silk fibroin, SF). Then, antibody-based immunoassays, i.e. enzyme-linked immunosorbent assay (ELISA) and immuno-fluorescence microscopy (IFM), were established and conducted in tandem to identify the corresponding protein in ancient silks. The anti-SF antibody exhibits high sensitivity and specificity for the identification of modern and ancient silks. The detection limit of the ELISA method is about 0.1 ng/mL, and no cross-reactions with other possible interference antigens have been noted. IFM makes it possible to localize target proteins in archaeological samples, and also ensure the reliability of the ELISA results. Based on these advantages, immunological techniques have the potential to become powerful analytical tools at archaeological sites and conservation science laboratories.


Assuntos
Arqueologia/métodos , Ensaio de Imunoadsorção Enzimática/métodos , Fibroínas/análise , Microscopia de Fluorescência/métodos , Têxteis/análise , Têxteis/história , Anticorpos/imunologia , Arqueologia/instrumentação , China , Fibroínas/imunologia , História Antiga , Sensibilidade e Especificidade
11.
Anal Bioanal Chem ; 407(13): 3861-7, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25804731

RESUMO

We report the preparation of a specific fibroin antibody and its use for the identification of unearthed ancient silk relics. Based on the 12-amino-acid repeat sequence "GAGAGSGAGAGS", which is found in fibroin of the silkworm Bombyx mori, a specific antibody against fibroin was prepared in rabbits through peptide synthesis and carrier-protein coupling. This antibody was highly specific for fibroin found in silk. Using this antibody we have successfully identified four silk samples from different time periods. Our results reveal, for the first time, a method capable of detecting silk from a few milligrams of archaeological fabric that has been buried for thousands of years, confirming that the ancient practice of wearing silk products while praying for rebirth dated back to at least 400 BCE. This method also complements current approaches in silk detection, especially for the characterization of poorly preserved silks, promoting the investigation of silk origins and of ancient clothing cultures.


Assuntos
Arqueologia/métodos , Ensaio de Imunoadsorção Enzimática/métodos , Fibroínas/química , Fibroínas/história , Têxteis/análise , Têxteis/história , Sequência de Aminoácidos , Sequência de Bases , China , Fibroínas/genética , História Antiga , Dados de Sequência Molecular , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
12.
Sci Rep ; 3: 2686, 2013 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-24135914

RESUMO

Nowadays most plant textiles used for clothing and household are made of cotton and viscose. Before the 19th century however, plant textiles were mainly made from locally available raw materials, in Scandinavia these were: nettle, hemp and flax. It is generally believed that in Viking and early Middle Ages Scandinavia hemp was used only for coarse textiles (i.e. rope and sailcloth). Here we present an investigation of 10 Scandinavian plant fibre textiles from the Viking and Early Middle Ages, believed to be locally produced. Up till now they were all believed to be made of flax. We show that 4 textiles, including two pieces of the famous Överhogdal Viking wall-hanging are in fact made with hemp (in three cases hemp and flax are mixed). This indicates that hemp was important, not only for coarse but also for fine textile production in Viking and Early Middle Ages in Scandinavia.


Assuntos
Cannabis/química , Têxteis/análise , Cannabis/anatomia & histologia , Vestuário/história , História Antiga , Humanos , Países Escandinavos e Nórdicos
13.
Anal Bioanal Chem ; 394(3): 871-82, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19352635

RESUMO

Young fustic (Cotinus coggygria Scop.; Anacardiaceae) has been used as a dyestuff since antiquity. Phytochemical investigation of the methanol extract of the heartwood has led to the isolation and structure elucidation by nuclear magnetic resonance and mass spectrometry (MS) of 3',4',6-trihydroxyaurone (sulfuretin) and 3',4',7-trihydroxyflavonol (fisetin) as well as 3',4',7-trihydroxyflavanol (fustin), 3',4',5,7-tetrahydroxyflavonol (quercetin), 3',4',5,7-tetrahydroxyflavanol (taxifolin), 4',7-dihydroxyflavanol, 3',4',7-trihydroxyflavanone (butin), 4',7-dihydroxyflavanone (liquiritigenin), trans-2',3,4,4'-tetrahydroxychalcone (butein), 4',5,7-trihydroxyflavanone and trans-2',4,4'-trihydroxychalcone (isoliquiritigenin). The isolated compounds were used as reference materials for the development of a high-performance liquid chromatography-diode array detector-MS method, which was then applied to analyse (1) fresh silk samples dyed with young fustic, (2) dyed silk subjected to artificially accelerated light ageing and (3) historical silk micro-samples, extracted from ecclesiastical post-Byzantine garments (fifteenth to eighteenth century), which belong to monasteries of Mount Athos. Sulfuretin and fisetin, which are usually used as markers for the identification of the yellow dye and, for the first time, some of the aforementioned flavonoid components of young fustic were identified in the historical extracts. Furthermore, preliminary experiments suggested that although the amounts of the dye components decrease with light ageing, the relative ratio of fisetin and sulfuretin, after a first step of ageing, seems to be almost unaffected by such degradation processes raised by light. The effect of the latter on the morphology of the dyed silk fibres is briefly investigated by scanning electron microscopy.


Assuntos
Anacardiaceae/química , Corantes/análise , Extratos Vegetais/análise , Têxteis/análise , Corantes/história , História do Século XV , História do Século XVI , História do Século XVII , História do Século XVIII , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Microscopia Eletrônica de Varredura , Extratos Vegetais/história , Reprodutibilidade dos Testes , Têxteis/história , Fatores de Tempo
14.
J Chromatogr A ; 1216(9): 1395-402, 2009 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-19168183

RESUMO

The natural dyes, and dye sources, in two seventeenth century Arraiolos carpets from the National Museum of Machado de Castro were analysed by high-performance liquid chromatography with UV-vis diode array detection (HPLC-DAD) and HPLC-mass spectrometry (LC-MS). Weld (Reseda luteola L.), indigo and spurge flax (Daphne gnidium L.) were found to be the dye sources, in agreement with original dyeing recipes collected during the nineteenth century. In order to fully characterize the plant sources, LC-MS conditions were optimized with plant extracts and the chromatographic separation and mass detection were enhanced. Extraction of the dyes, in the Arraiolos carpet samples, was performed using mild conditions that avoid glycoside decomposition. For the blues a dimethylformamide solution proved to be efficient for indigotin recovery. For all the other colours, an improved mild extraction method (with oxalic acid, methanol, acetone and water) was used, enabling to obtain the full dye source fingerprint, namely the flavonoid glycosides in the yellow dyes.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Corantes/análise , Daphne/química , Espectrometria de Massas/métodos , Resedaceae/química , Cromatografia Líquida/métodos , Corantes/história , Flavonoides/análise , Pisos e Cobertura de Pisos/história , Glicosídeos/análise , História do Século XVII , Extratos Vegetais/análise , Têxteis/análise , Têxteis/história
15.
J Agric Food Chem ; 56(19): 9127-32, 2008 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-18778029

RESUMO

In the present study the phenolic composition of leaves, stalks, and textile fiber extracts from Urtica dioica L. is described. Taking into account the increasing demand for textile products made from natural fibers and the necessity to create sustainable "local" processing chains, an Italian project was funded to evaluate the cultivation of nettle fibers in the region of Tuscany. The leaves of two nettle samples, cultivated and wild (C and W), contain large amounts of chlorogenic and 2- O-caffeoylmalic acid, which represent 71.5 and 76.5% of total phenolics, respectively. Flavonoids are the main class in the stalks: 54.4% of total phenolics in C and 31.2% in W samples. Anthocyanins are second in quantitative importance and are present only in nettle stalks: 28.6% of total phenolics in C and 24.4% in W extracts. Characterization of phenolic compounds in nettle extracts is an important result with regard to the biological properties (antioxidant and antiradical) of these metabolites for their possible applications in various industrial activities, such as food/feed, cosmetics, phytomedicine, and textiles.


Assuntos
Cromatografia Líquida de Alta Pressão , Fenóis/análise , Folhas de Planta/química , Caules de Planta/química , Têxteis/análise , Urtica dioica/química , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem , Urtica dioica/crescimento & desenvolvimento
16.
Transgenic Res ; 17(1): 133-47, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17372706

RESUMO

Flax (Linum usitatissimum L.) is a raw material used for important industrial products. Linen has very high quality textile properties, such as its strength, water absorption, comfort and feel. However, it occupies less than 1% of the total textile market. The major reason for this is the long and difficult retting process by which linen fibres are obtained. In retting, bast fibre bundles are separated from the core, the epidermis and the cuticle. This is accomplished by the cleavage of pectins and hemicellulose in the flax cell wall, a process mainly carried out by plant pathogens like filamentous fungi. The remaining bast fibres are mainly composed of cellulose and lignin. The aim of this study was to generate plants that could be retted more efficiently. To accomplish this, we employed the novel approach of transgenic flax plant generation with increased polygalacturonase (PGI ) and rhamnogalacturonase (RHA) activities. The constitutive expression of Aspergillus aculeatus genes resulted in a significant reduction in the pectin content in tissue-cultured and field-grown plants. This pectin content reduction was accompanied by a significantly higher (more than 2-fold) retting efficiency of the transgenic plant fibres as measured by a modified Fried's test. No alteration in the lignin or cellulose content was observed in the transgenic plants relative to the control. This indicates that the over-expression of the two enzymes does not affect flax fibre composition. The growth rate and soluble sugar and starch contents were in the range of the control levels. It is interesting to note that the RHA and PGI plants showed higher resistance to Fusarium culmorum and F. oxysporum attack, which correlates with the increased phenolic acid level. In this report, we demonstrate for the first time that over-expression of the A. aculeatus genes results in flax plants more readily usable for fibre production. The biochemical parameters of the cell wall components indicated that the fibre quality remains similar to that of wild-type plants, which is an important pre-requisite for industrial applications.


Assuntos
Linho/enzimologia , Linho/genética , Poligalacturonase/genética , Têxteis/análise , Aspergillus/enzimologia , Aspergillus/genética , Sequência de Bases , Celulose/metabolismo , Primers do DNA/genética , Linho/microbiologia , Fusarium/patogenicidade , Expressão Gênica , Genes Fúngicos , Hidroxibenzoatos/metabolismo , Lignina/metabolismo , Pectinas/metabolismo , Plantas Geneticamente Modificadas
17.
Biotechnol Bioeng ; 87(4): 552-63, 2004 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-15286993

RESUMO

Decolorization of textile dyes by a laccase from Trametes modesta immobilized on gamma-aluminum oxide pellets was studied. An enzyme reactor was equipped with various UV/Vis spectroscopic sensors allowing the continuous online monitoring of the decolorization reactions. Decolorization of the dye solutions was followed via an immersion transmission probe. Adsorption processes were observed using diffuse reflectance measurements of the solid carrier material. Generally, immobilization of the laccase does not seem to sterically affect dye decolorization. A range of commercial textile dyes was screened for decolorization and it was found that the application of this enzymatic remediation system is not limited to a certain structural group of dyes. Anthrachinonic dyes (Lanaset Blue 2R, Terasil Pink 2GLA), some azo dyes, Indigo Carmine, and the triphenylmethane dye Crystal Violet were efficiently decolorized. However, the laccase displayed pronounced substrate specificities when a range of structurally related model azodyes was subjected to the biotransformation. Azodyes containing hydroxy groups in ortho or para position relative to the azo bond were preferentially oxidized. The reactor performance was studied more closely using Indigo Carmine.


Assuntos
Óxido de Alumínio/química , Basidiomycota/enzimologia , Reatores Biológicos , Cor , Corantes/química , Lacase/química , Espectrofotometria Ultravioleta/métodos , Compostos Azo/química , Ativação Enzimática , Enzimas Imobilizadas/química , Cinética , Sistemas On-Line , Têxteis/análise , Purificação da Água/métodos
18.
J Forensic Sci ; 49(3): 469-76, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15171161

RESUMO

Pepper sprays are used in a variety of circumstances, including criminal activity, self-defense, and law enforcement. As such, the presence or absence of pepper sprays on evidentiary materials is often important when determining the facts of an incident. When no visible stains are present on evidentiary materials, ascertaining the presence or absence of pepper spray can be a challenge to the forensic analyst. A method, based on a chemical derivatization of capsaicinoids using a diazonium salt, has been developed for the visualization of colorless, ultraviolet (UV) activated fluorescent dye-free pepper sprays on textiles. Identification of both the capsaicinoids and their derivatives is confirmed via extraction of the derivatized capsaicinoids followed by liquid chromatography/mass spectrometry (LC/MS) analysis. LC/MS analysis is conducted using a YMC Basic column and elution of the compounds using a gradient of 10 mM ammonium formate, pH 4.2 and methanol at 0.35 mL/min. Full-scan MS data are collected for the full 6.5 min LC analysis. Although this method is qualitative in nature, visual detection of as little as 50 microL of a 0.2% pepper spray (equivalent to approximately 0.1 mg) on a variety of garments is possible, and more than adequate signal-to-noise is obtained for reconstructed ion chromatograms on LC/MS analysis at these levels.


Assuntos
Medicina Legal/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Extratos Vegetais/química , Aerossóis , Desinfetantes , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Lavanderia , Estrutura Molecular , Peso Molecular , Têxteis/análise
19.
Ann Bot ; 93(5): 603-7, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15037446

RESUMO

BACKGROUND AND AIMS: Fabrics used in pollination bags may exclude pollen carried by biotic vectors, but have varying degrees of permeability to wind-borne pollen. The permeability of bags to wind-borne pollen may have important consequences in studies of pollination and reproductive biology. The permeability of four fabrics commonly used in the construction of pollination bags was examined. METHODS: Deposition of wind-borne pollen on horizontally and vertically oriented microscope slides was assessed on slides enclosed in pollination bags, as well as on control slides. KEY RESULTS: It was found that the permeability of fabrics to wind-borne pollen, as measured by deposition on both horizontally and vertically oriented slides, decreased with pore size. However, deposition on horizontal slides was always greater than on vertical slides for a given fabric; this could manifest itself as differential success of pollination of flowers in bags-dependent on flower orientation. CONCLUSIONS: Obviously, bags with mesh size smaller than most pollen grains are impermeable to pollen. However, material for such bags is very expensive. In addition, it was also observed that bags with even moderately small pore size, such as pores (approx. 200 microm) in twisted fibre cotton muslin, offered highly significant barriers to passage of wind-borne pollen. Such bags are sufficiently effective in most large-sample-size reproductive biology studies.


Assuntos
Pólen/fisiologia , Têxteis/análise , Desenho de Equipamento , Permeabilidade , Vento
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