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1.
J Environ Manage ; 360: 121210, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38781878

RESUMO

The food industry requires new production models that include more environmentally friendly waste management practices, considering that the environmental loads of solid waste and wastewater associated with this sector cause damage to the receiving ecosystems. The approach considered in this study focuses on the design and environmental assessment of an enzymatic process for the valorization of ferulic acid present in the effluent of a corn tortilla plant. The ferulic acid can be immobilized on chitosan so that the ferulic acid grafted chitosan can be used as a bioactive film with enhanced antioxidant properties with potential applications in the biotechnology sector. Its real projection approach requires the evaluation of its environmental and economic performance, trying to identify its benefits and potential in the value chain, using the Techno-Economic Analysis (TEA) as a phase for the conceptual design of the process and the Life Cycle Assessment (LCA) methodology for the environmental evaluation. It should be noted that the TEA indicators are promising, since the values of the financial indicators obtained are representative of the economic profitability, which makes the ferulic acid valorization a viable process. In terms of the environmental impact of the process, the buffer dose and the chitosan production process are identified as the main critical points. This double benefit in environmental and economic terms shows that the valorization of ferulic acid for chitosan functionalization is a promising alternative to improve the sustainability performance of corn processing.


Assuntos
Quitosana , Ácidos Cumáricos , Zea mays , Quitosana/química , Ácidos Cumáricos/química , Polímeros/química , Gerenciamento de Resíduos/métodos
2.
Molecules ; 24(8)2019 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-30999714

RESUMO

10,16-dihydroxyhexadecanoic acid obtained from agroresidual tomato waste, was oxidized to produce 7-oxohexadecanedioic acid in good yield (>70%) and purified without oxidation side products in one step. Polycondensation with 1,8-octanediol, yielded the polyester (poly(ω-carboxyl PA-co-OD)) with Mw = 2155.15 and Mn = 1637.27. The best enzymatic reaction conditions to get the polyester were using lipase CAL-B (%-by-wt relative to monomer) in toluene as a solvent for 1 h at 60 °C. The poly(ω-carboxyl PA-co-OD) was characterized by 1H- and 13C-NMR, mass spectrometry (MALDI-TOF) and the polyester film formed with a Langmuir-Blodgett Trough was analyzed by means of spectroscopic ellipsometry and atomic force microscopy.


Assuntos
Lipase/química , Ácidos Palmíticos/química , Poliésteres , Solanum lycopersicum/química , Enzimas Imobilizadas , Proteínas Fúngicas , Poliésteres/síntese química , Poliésteres/química
3.
Dis Aquat Organ ; 113(2): 103-11, 2015 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-25751853

RESUMO

Anisakid nematodes have been identified in a wide variety of fish and marine mammal species. In Brazil, Anisakis physeteris, A. insignis, A. typica, A. nascetti, and those of the A. simplex complex have been reported infecting fishes and cetaceans. In this study, specimens collected from a dwarf sperm whale Kogia sima (Owen, 1866) stranded on the northeastern coast of Brazil were identified through morphological and genetic analyses as A. paggiae. Anisakids were examined through differential interference contrast light and scanning electron microscopy (SEM). Morphological and morphometric analysis revealed that these specimens belonged to Anisakis sp. clade II and more specifically to A. paggiae, exhibiting a violin-shaped ventriculus and 3 denticulate caudal plates, which are taxonomic characters considered unique to this species. Genetic analysis based on the mtDNA cox2 gene confirmed our identification of A. paggiae. Phylogenetic trees using both maximum likelihood and neighbor-joining methods revealed a strongly supported monophyletic clade (bootstrap support = 100%) with all available A. paggiae sequences. Integrative taxonomic analysis allowed the identification of A. paggiae for the first time in Brazilian waters, providing new data about their geographical distribution. Moreover, here we present the first SEM images of this species.


Assuntos
Anisakis/genética , Anisakis/ultraestrutura , Infecções por Nematoides/veterinária , Baleias/parasitologia , Animais , Oceano Atlântico , Sequência de Bases , Brasil , DNA de Helmintos/genética , Infecções por Nematoides/epidemiologia , Infecções por Nematoides/parasitologia , Filogenia
4.
Mem Inst Oswaldo Cruz ; 107(2): 186-93, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22415256

RESUMO

Taking into account the difficulties of taxonomic identification of larval anisakid nematodes based on morphological characters, genetic analyses were performed, together with those usually applied, in order to identify anisakid larvae found in the flounder Paralichthys isosceles from the littoral of the state of Rio de Janeiro, Brazil. The analysis of 1,820 larvae revealed a new species, similar to Hysterothylacium MD, Hysterothylacium 2, Hysterothylacium KB and Hysterothylacium sp regarding the absence of the larval tooth, an excretory pore situated below the nerve ring level, and slender lateral alae. Moreover, the new species differs from Hysterothylacium fortalezae and Hysterothylacium reliquens with regard to the number and size of spines present on the tail end and from Hysterothylacium patagonicus by the absence of interlabia. The maximum parsimony and neighbour joining tree topologies based on the 18S ribosomal DNA gene, complete internal transcribed spacer region and cytochrome oxidase 2 (COII) gene demonstrated that the Brazilian larvae belong to Raphidascarididae and represent a unique genetic entity, confirmed as a new Hysterothylacium species. Furthermore, the new species presents COII genetic signatures and shares polymorphisms with Raphidascarididae members. This is the first description of a new anisakid species from Brazil through the integration of morphological and molecular taxonomy data.


Assuntos
Anisakis/anatomia & histologia , Anisakis/genética , Linguado/parasitologia , Animais , Anisakis/classificação , Anisakis/ultraestrutura , Brasil , Tipagem Molecular/métodos
5.
Vet Parasitol ; 283: 109164, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32544763

RESUMO

Mammomonogamus spp. are parasites with curious characteristics, such as the "Y" shape that results from male and female maintaining the permanent copulation position and the controversial presence or absence of spicules. These nematodes are hematophagous and cause damage to the upper respiratory tracts of cattle, sheep, goats, deer, wild yaks, and orangutans. Human infection is rare and most cases until now have been in the Caribbean Islands or in Brazil, and mainly in farmworkers but recently there have been reports affecting tourists. In the present work, the parasites were recovered from the laryngopharynx and larynx region of Bubalus bubalis on the island of Marajó, Pará, Brazil. Different microscopy methodologies were applied (bright field, fluorescence, and scanning electron microscopy) to explore the ultrastructural details of the anterior end, genital structures and the host tissue damage caused by the nematodes. The well-developed mouth is an important structure in the identification of these nematodes and used by the parasite to adhere to the host's tissue. Different methodologies in microscopy and molecular biology contributed to a detailed morphological description and showed the phenotypic position of Mammomonogamus laryngeus. Light and scanning electron microscopy (SEM) showed details of the papillae, amphids, festoons, ribs, and teeth. Fluorescence microscopy enabled a detailed characterization of different structures, such as the bursal rays and SEM enabled the visualization of the specialized features of the cuticle surface in the male and female. Histopathological analyses, cryofracture and environmental SEM experiments of the infected tissues were carried out in order to investigate the lesions resultant from the parasitism. In addition, the parasite couples were submitted to cryofracture and these results revealed details of the reproductive structures of both sexes, including the male spicule.


Assuntos
Búfalos , Metastrongyloidea/fisiologia , Infecções por Strongylida/veterinária , Animais , Brasil/epidemiologia , Feminino , Hipofaringe/parasitologia , Laringe/parasitologia , Masculino , Prevalência , Infecções por Strongylida/epidemiologia , Infecções por Strongylida/parasitologia , Infecções por Strongylida/patologia
6.
J Neurosci Methods ; 158(1): 64-74, 2006 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-16797719

RESUMO

In sections of paraformaldehyde fixed brain tissue, stained using immunohistochemical methods, the distribution of staining within the sections is not uniform. Whilst stained cells are seen at the top and bottom surfaces, the central thicknesses of the sections contain little or no immunoreactivity. This presents a major problem for quantification, as each section contains a population of cells that is not visualized by the staining method. Following extensive investigation of this phenomenon, we report that the failure of full thickness, immunohistochemical staining is not a failure of the immunohistochemical methodology per se, nor is it related directly to the thickness of the sections used. Rather, the problem lies in the chemistry of the tissue itself, and originates during fixation of the tissues using paraformaldehyde-based perfusion methods, which render the cell membranes impermeable to one or more components of the staining protocol. We show that this impermeability is affected by addition of membrane-disrupting agents to the fixative, and by a reduction of exposure to paraformaldehyde during fixation. The present investigation contributes to the development of new fixation protocols, optimised for use in both immunohistochemical methods and morphometric analyses.


Assuntos
Fixadores/farmacologia , Formaldeído/farmacologia , Imuno-Histoquímica , Neurônios/efeitos dos fármacos , Polímeros/farmacologia , Fixação de Tecidos/métodos , Adenoviridae/fisiologia , Animais , Encéfalo/citologia , Encéfalo/efeitos dos fármacos , Fosfoproteína 32 Regulada por cAMP e Dopamina/metabolismo , Feminino , Vetores Genéticos/fisiologia , Microscopia Imunoeletrônica/métodos , Neurônios/metabolismo , Neurônios/ultraestrutura , Ratos , Ratos Sprague-Dawley , Inclusão do Tecido/métodos
7.
Recent Pat Biotechnol ; 3(2): 88-102, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19519565

RESUMO

Peroxidases are hemoenzymes with a wide range of applications, from fine chemical synthesis to environmental biocatalysis. These outstanding biocatalysts are able to catalyze reactions such as heteroatom oxidation (N- and S-oxidation), epoxidation, hydroxylation, and the oxidation of alcohols and indole, often giving high yields and enantiomeric excess values. This makes these biocatalysts very useful for application to several biotechnological processes. In this paper, recent advances and patents surrounding the use of peroxidases are reviewed, covering different aspects related to the applications of peroxidases and the modifications carried out to improve their functionality as biocatalysts.


Assuntos
Patentes como Assunto , Peroxidases/metabolismo , Biocatálise , Biopolímeros/metabolismo , Biotransformação , Peroxidase do Rábano Silvestre/metabolismo , Oxirredução , Peroxidases/química , Peroxidases/classificação , Estereoisomerismo
8.
Mem. Inst. Oswaldo Cruz ; 107(2): 186-193, Mar. 2012. ilus
Artigo em Inglês | LILACS | ID: lil-617063

RESUMO

Taking into account the difficulties of taxonomic identification of larval anisakid nematodes based on morphological characters, genetic analyses were performed, together with those usually applied, in order to identify anisakid larvae found in the flounder Paralichthys isosceles from the littoral of the state of Rio de Janeiro, Brazil. The analysis of 1,820 larvae revealed a new species, similar to Hysterothylacium MD, Hysterothylacium 2, Hysterothylacium KB and Hysterothylacium sp regarding the absence of the larval tooth, an excretory pore situated below the nerve ring level, and slender lateral alae. Moreover, the new species differs from Hysterothylacium fortalezae and Hysterothylacium reliquens with regard to the number and size of spines present on the tail end and from Hysterothylacium patagonicus by the absence of interlabia. The maximum parsimony and neighbour joining tree topologies based on the 18S ribosomal DNA gene, complete internal transcribed spacer region and cytochrome oxidase 2 (COII) gene demonstrated that the Brazilian larvae belong to Raphidascarididae and represent a unique genetic entity, confirmed as a new Hysterothylacium species. Furthermore, the new species presents COII genetic signatures and shares polymorphisms with Raphidascarididae members. This is the first description of a new anisakid species from Brazil through the integration of morphological and molecular taxonomy data.


Assuntos
Animais , Anisakis/anatomia & histologia , Anisakis/genética , Linguado/parasitologia , Anisakis/classificação , Anisakis/ultraestrutura , Brasil , Tipagem Molecular/métodos
9.
J Biol Chem ; 281(6): 3513-20, 2006 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-16293614

RESUMO

Protein-tyrosine kinases and Rho GTPases regulate many cellular processes, including the reorganization and dynamics of the actin cytoskeleton. The Wiskott-Aldrich syndrome protein (WASP) and its homolog neuronal WASP (N-WASP) are effectors of the Rho GTPase Cdc42 and provide a direct link between activated membrane receptors and the actin cytoskeleton. WASP and N-WASP are also regulated by a large number of other activators, including protein-tyrosine kinases, phosphoinositides, and Src homology 3-containing adaptor proteins, and can therefore serve as signal integrators inside cells. Here we show that Cdc42 and the Src family kinase Lck cooperate at two levels to enhance WASP activation. First, autoinhibition in N-WASP decreases the efficiency (kcat/Km) of phosphorylation and dephosphorylation of the GTPase binding domain by 30- and 40-fold, respectively, and this effect is largely reversed by Cdc42. Second, Cdc42 and the Src homology 3-Src homology 2 module of Lck cooperatively stimulate the activity of phosphorylated WASP, with coupling energy of approximately 2.4 kcal/mol between the two activators. These combined effects provide mechanisms for high specificity in WASP activation by coincident GTPase and kinase signals.


Assuntos
GTP Fosfo-Hidrolases/metabolismo , Neurônios/metabolismo , Proteínas Tirosina Quinases/metabolismo , Proteína Neuronal da Síndrome de Wiskott-Aldrich/metabolismo , Proteína da Síndrome de Wiskott-Aldrich/metabolismo , Actinas/química , Actinas/metabolismo , Animais , Bovinos , Citoesqueleto/metabolismo , Ativação Enzimática , GTP Fosfo-Hidrolases/química , Humanos , Cinética , Proteína Tirosina Quinase p56(lck) Linfócito-Específica/metabolismo , Modelos Biológicos , Óxido Nítrico Sintase Tipo I/metabolismo , Fosforilação , Polímeros/química , Ligação Proteica , Conformação Proteica , Estrutura Terciária de Proteína , Proteína da Síndrome de Wiskott-Aldrich/química , Família de Proteínas da Síndrome de Wiskott-Aldrich/metabolismo , Proteína Neuronal da Síndrome de Wiskott-Aldrich/química , Proteína cdc42 de Ligação ao GTP/química , Proteína cdc42 de Ligação ao GTP/metabolismo , Domínios de Homologia de src
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