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1.
Ciênc. rural (Online) ; 53(2): e20210679, 2023. tab, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1412061

Resumo

This research carried out a bibliometric analysis and literature review on the production of gelatin-based films for application as food packaging, addressing the main advances and limitations. The search for articles was performed in the Scopus database, and bibliometric data were obtained using the Bibliometrix tool (RStudio software). It was observed that a wide variety of compounds can be incorporated into gelatin films to overcome the limitations related to their high solubility and low mechanical properties, as well as to obtain active or smart functions. Among the most reported compounds were essential oils, pigments extracted from vegetables, and other antimicrobial agents. The most reported foods as an application matrix were meat (fish, chicken, and shrimp), milk, cheese, and minimally processed fruits. Even with promising trends, the biggest challenge for large-scale applications is to obtain easily degradable biopolymers with structural and functional stability similar to synthetic polymers. Thus, a greater focus on this theme in research may favor significant advances in the use of these packages and positively impact several of the Sustainable Development Goals, as recommended by the United Nations.


Este estudo objetivou realizar uma análise bibliométrica e revisão de literatura acerca da produção de filmes à base de gelatina para aplicação como embalagens alimentícias, abordando os principais avanços e limitações. A busca de artigos foi realizada na base de dados da Scopus e os dados bibliométricos obtidos pela ferramenta Bibliometrix (RStudio software). Verificou-se uma grande variedade de compostos que podem ser incorporados nos filmes de gelatina, a fim de superar suas limitações relacionadas à alta solubilidade e baixas propriedades mecânicas, bem como para obtenção de funções ativas ou inteligentes. Dentre os compostos mais reportados, têm-se: óleos essenciais, pigmentos extraídos de vegetais e outros agentes antimicrobianos. Os alimentos mais reportados como matriz de aplicação foram: carnes (peixe, frango e camarão), leite, queijo e frutas, minimamente processadas. Mesmo com tendências promissoras, o maior desafio no âmbito das aplicações reais em larga escala é a obtenção de biopolímeros facilmente degradáveis, com estabilidade estrutural e funcional similar aos polímeros sintéticos. Dessa forma, o maior enfoque dessa temática em pesquisas poderá favorecer avanços significativos para o uso dessas embalagens, impactando positivamente diversos dos Objetivos para o Desenvolvimento Sustentável, preconizados pela Organização das Nações Unidas.


Assuntos
Biopolímeros , Embalagem de Alimentos , Conservação dos Recursos Naturais , Plásticos Biodegradáveis , Gelatina
2.
Ciênc. rural (Online) ; 53(2): e20210679, 2023. tab, graf
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1384560

Resumo

ABSTRACT: This research carried out a bibliometric analysis and literature review on the production of gelatin-based films for application as food packaging, addressing the main advances and limitations. The search for articles was performed in the Scopus database, and bibliometric data were obtained using the Bibliometrix tool (RStudio software). It was observed that a wide variety of compounds can be incorporated into gelatin films to overcome the limitations related to their high solubility and low mechanical properties, as well as to obtain active or smart functions. Among the most reported compounds were essential oils, pigments extracted from vegetables, and other antimicrobial agents. The most reported foods as an application matrix were meat (fish, chicken, and shrimp), milk, cheese, and minimally processed fruits. Even with promising trends, the biggest challenge for large-scale applications is to obtain easily degradable biopolymers with structural and functional stability similar to synthetic polymers. Thus, a greater focus on this theme in research may favor significant advances in the use of these packages and positively impact several of the Sustainable Development Goals, as recommended by the United Nations.


RESUMO: Este estudo objetivou realizar uma análise bibliométrica e revisão de literatura acerca da produção de filmes à base de gelatina para aplicação como embalagens alimentícias, abordando os principais avanços e limitações. A busca de artigos foi realizada na base de dados da Scopus e os dados bibliométricos obtidos pela ferramenta Bibliometrix (RStudio software). Verificou-se uma grande variedade de compostos que podem ser incorporados nos filmes de gelatina, a fim de superar suas limitações relacionadas à alta solubilidade e baixas propriedades mecânicas, bem como para obtenção de funções ativas ou inteligentes. Dentre os compostos mais reportados, têm-se: óleos essenciais, pigmentos extraídos de vegetais e outros agentes antimicrobianos. Os alimentos mais reportados como matriz de aplicação foram: carnes (peixe, frango e camarão), leite, queijo e frutas, minimamente processadas. Mesmo com tendências promissoras, o maior desafio no âmbito das aplicações reais em larga escala é a obtenção de biopolímeros facilmente degradáveis, com estabilidade estrutural e funcional similar aos polímeros sintéticos. Dessa forma, o maior enfoque dessa temática em pesquisas poderá favorecer avanços significativos para o uso dessas embalagens, impactando positivamente diversos dos Objetivos para o Desenvolvimento Sustentável, preconizados pela Organização das Nações Unidas.

3.
Acta sci., Biol. sci ; 44: e58543, mar. 2022. tab, ilus, graf
Artigo em Inglês | VETINDEX | ID: biblio-1368012

Resumo

Microbial polysaccharides are of great biotechnological and commercial interest and have wide application in the food, cosmetic and medicine industries. Exopolysaccharide (EPS) production by the yeast Cryptococcus laurentii SD7, isolated from fresh water molluscs, was studied using agro-industrial byproducts as substrates in the submerged fermentation. The Central Composite Design (CCD) 23 was used to study the influence of pH, different concentrations on sugarcane molasses and corn steep liquor (CSL), for 48 hours. According to the results, the highest EPS production occurred at the initial pH 5 and at 8.4% concentration of sugarcane molasses, which were statistically significant variable at 10% (p < 0.1). The concentration of CSL had no influence in the studied range, thus, it can be used lowest concentration (0.3%). The time course of EPS production showed that while cell growth peaked within 48 hours, the highest EPS production (6.61 g L-1) occurred at 168 hours, with a productivity of about 0.04 g L-1 h-1. The pH of the medium remained approximately constant throughout the fermentation process. The yeast C. laurentii SD7 showed great potential for EPS production at a low cost and with sustainable substrates.(AU)


Assuntos
Melaço , Substratos para Tratamento Biológico , Zea mays , Cryptococcus , Polissacarídeos , Biopolímeros
4.
Acta sci., Biol. sci ; 44: e59982, mar. 2022. ilus, tab
Artigo em Inglês | VETINDEX | ID: biblio-1370239

Resumo

The use of fungi to obtain chitin and chitosan has advantages such as handling, extraction, and production control, thus allowing to generate high quality chitosan. This study aimed to isolate and identify strains of Cunninghamella spp., and assess the production of biomass, chitin, and chitosan. We determined the macroscopic and microscopic phenotypic aspects of the superiors, mycelial growth rate index, consumption of glucose and nitrogen, as well as the pH variation, and the production of biomass, chitin, and chitosan. After assessing the mycelial growth speed index, considered fast, we found that the UFT-Ce08 and UFT-Ce09 isolates showed a higher growth speed. Therefore, we assessed the sporulation of the isolates, and all of them reached the concentration of 106spores mL-1in the period of 96 hours. The YPD was considered ideal for biomass production because it promotes an efficient consumption and synthesis of organic compounds by microorganisms. The assessment of the biomass production and the chitin and chitosan yield of nine isolates and the reference strain showed that the UFT-Ce08 isolate had the highest amount of biomass, the UFT-Ce11 isolate had the highest chitin yield, and despite having the second smallest biomass, the UFT-Ce09 isolate had thehighest chitosan yield. Seven isolates showed higher chitosan yield than the reference strain. Therefore, chitosan production from this fungus can be further optimized to improve yield on a large-scale production. Chitosan production from this fungus can be further optimized to improve yield in large-scale production.(AU)


Assuntos
Biotecnologia , Quitina , Cunninghamella/isolamento & purificação , Quitosana , Biomassa
5.
Arq. Ciênc. Vet. Zool. UNIPAR (Online) ; 25(2): e6378, jul-dez. 2022.
Artigo em Português | LILACS, VETINDEX | ID: biblio-1399609

Resumo

Os resíduos provenientes da aquicultura são derivados da ração e da excreção dos peixes e podem estar sedimentados, suspensos ou dissolvidos, ocasionando elevados valores de DBO, DQO, nitrogênio e fósforo. A produção de camarões no Brasil tem gerado elevadas quantidades de resíduos sólidos, tendo em vista que os exoesqueletos dos camarões correspondem a cerca de 40% do seu peso total, resultando num forte impacto ambiental. Diversas pesquisas envolvendo a quitina estão sendo desenvolvidas na área de tratamento de água, devido principalmente a sua capacidade de formar filme, sendo utilizada em sistemas filtrantes. Este polissacarídeo também pode ser utilizado como agente floculante no tratamento de efluentes, como adsorvente na clarificação de óleos, e principalmente na produção de quitosana. Atualmente a quitosana possui aplicações multidimensionais, desde áreas como a nutrição humana, biotecnologia, ciência dos materiais, indústria farmacêutica, agricultura, terapia genética e proteção ambiental. A quitosana é muito eficiente na remoção de poluentes em diferentes concentrações. Apresenta alta capacidade e grande velocidade de adsorção, boa eficiência e seletividade tanto em soluções que possuem altas ou baixas concentrações. O uso da biotecnologia, através do processo de adsorção utilizando adsorventes naturais e baratos, como a quitina e quitosana, minimiza os impactos ambientais da aquicultura tanto em relação aos provocados pelo lançamento de efluentes no meio ambiente quanto aos causados pelo descarte inadequado dos resíduos do processamento de camarões.(AU)


Aquaculture residues are derived from fish feed and excretion and may be sedimented, suspended or dissolved, resulting in high BOD, COD, nitrogen and phosphorus values. Shrimp production in Brazil has generated high amounts of solid waste, since shrimp exoskeletons account for about 40% of their total weight, resulting in a strong environmental impact. Several researches involving chitin are being developed in the area of water treatment, mainly due to its ability to form film, being used in filter systems. This polysaccharide can also be used as a flocculating agent in the treatment of effluents, as an adsorbent in the clarification of oils, and especially in the production of chitosan. Currently, chitosan has multidimensional applications, from areas such as human nutrition, biotechnology, materials science, pharmaceutical industry, agriculture, gene therapy and environmental protection. Chitosan is very efficient in the removal of pollutants at different concentrations. It presents high capacity and high adsorption velocity, good efficiency and selectivity both in solutions that have high or low concentrations. The use of biotechnology, through the adsorption process using natural and cheap adsorbents such as chitin and chitosan, minimizes the environmental impacts of aquaculture both in relation to those caused by the release of effluents into the environment and those caused by the inappropriate disposal of processing residues of shrimps.(AU)


Los residuos procedentes de la acuicultura se derivan de la ración y de la excreción de los peces y pueden estar sedimentados, suspendidos o disueltos, ocasionando elevados valores de DBO, DQO, nitrógeno y fósforo. La producción de camarones en Brasil ha generado grandes cantidades de residuos sólidos, teniendo en cuenta que los exoesqueletos de los camarones corresponden a cerca del 40% de su peso total, resultando en un fuerte impacto ambiental. Varias investigaciones involucrando la quitina se están desarrollando en el área de tratamiento de agua, debido principalmente a su capacidad de formar película, siendo utilizada en sistemas filtrantes. Este polisacárido también puede ser utilizado como agente floculante en el tratamiento de efluentes, como adsorbente en la clarificación de aceites, y principalmente en la producción de quitosana. Actualmente la quitosana posee aplicaciones multidimensionales, desde áreas como la nutrición humana, biotecnología, ciencia de los materiales, industria farmacéutica, agricultura, terapia genética y protección ambiental. La quitosana es muy eficiente en la eliminación de contaminantes en diferentes concentraciones. Presenta alta capacidad y gran velocidad de adsorción, buena eficiencia y selectividad tanto en soluciones que poseen altas o bajas concentraciones. El uso de la biotecnología, a través del proceso de adsorción utilizando adsorbentes naturales y baratos, como la quitina y quitosana, minimiza los impactos ambientales de la acuicultura tanto en relación a los provocados por el lanzamiento de efluentes en el medio ambiente en cuanto a los causados por el descarte inadecuado de los residuos del procesamiento de camarones.(AU)


Assuntos
Quitina/administração & dosagem , Adsorção/efeitos dos fármacos , Quitosana/administração & dosagem , Águas Residuárias/química , Biopolímeros/análise , Aquicultura , Eutrofização/fisiologia , Amônia/química
6.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1461033

Resumo

Microbial polysaccharides are of great biotechnological and commercial interest and have wide application in the food, cosmetic and medicine industries. Exopolysaccharide (EPS) production by the yeast Cryptococcus laurentii SD7, isolated from fresh water molluscs, was studied using agro-industrial byproducts as substrates in the submerged fermentation. The Central Composite Design (CCD) 23 was used to study the influence of pH, different concentrations on sugarcane molasses and corn steep liquor (CSL), for 48 hours. According to the results, the highest EPS production occurred at the initial pH 5 and at 8.4% concentration of sugarcane molasses, which were statistically significant variable at 10% (p < 0.1). The concentration of CSL had no influence in the studied range, thus, it can be used lowest concentration (0.3%). The time course of EPS production showed that while cell growth peaked within 48 hours, the highest EPS production (6.61 g L-1) occurred at 168 hours, with a productivity of about 0.04 g L-1 h-1. The pH of the medium remained approximately constant throughout the fermentation process. The yeast C. laurentii SD7 showed great potential for EPS production at a low cost and with sustainable substrates.


Microbial polysaccharides are of great biotechnological and commercial interest and have wide application in the food, cosmetic and medicine industries. Exopolysaccharide (EPS) production by the yeast Cryptococcus laurentii SD7, isolated from fresh water molluscs, was studied using agro-industrial byproducts as substrates in the submerged fermentation. The Central Composite Design (CCD) 23 was used to study the influence of pH, different concentrations on sugarcane molasses and corn steep liquor (CSL), for 48 hours. According to the results, the highest EPS production occurred at the initial pH 5 and at 8.4% concentration of sugarcane molasses, which were statistically significant variable at 10% (p < 0.1). The concentration of CSL had no influence in the studied range, thus, it can be used lowest concentration (0.3%). The time course of EPS production showed that while cell growth peaked within 48 hours, the highest EPS production (6.61 g L-1) occurred at 168 hours, with a productivity of about 0.04 g L-1 h-1. The pH of the medium remained approximately constant throughout the fermentation process. The yeast C. laurentii SD7 showed great potential for EPS production at a low cost and with sustainable substrates.

7.
Acta sci., Biol. sci ; 41: e43661, 20190000. ilus, tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1460864

Resumo

Biodiesel production has been increasing yearly in Brazil. A large amount of glycerin is generated in this process and needs a correct destination. One possible use of this glycerin in crude form is in biotechnological processes. Xanthan gum is a commercial gum used primarily in the pharmaceutical and food industries as thickener, emulsifier and stabilizer. It is synthetized by species of the bacterium Xanthomonas generally from glucose. However, current research shows that species of this bacterium have the capacity to grow and synthesize the gum using glycerin from biodiesel. The aim of this study was to produce xanthan gum using glycerin from biodiesel production in medium with different nitrogen content, named complex and simple media. The kinetics of fermentation in simple medium showed a twofold increase in gum production (3.16 kg.m-3) compared to the one in complex medium (1.46 kg.m-3) after 120 hours. The gum generated in this study showed chemical and rheological characteristics of xanthan gum. Glucose supplementation did not show an increase in xanthan production but did increase the consistency index and the behavioral index of solutions of this gum.


Assuntos
Biocombustíveis/análise , Biotecnologia , Glicerol , Xanthomonas , Glucose
8.
Acta Sci. Biol. Sci. ; 41: e43661, 2019. ilus, tab, graf
Artigo em Inglês | VETINDEX | ID: vti-763458

Resumo

Biodiesel production has been increasing yearly in Brazil. A large amount of glycerin is generated in this process and needs a correct destination. One possible use of this glycerin in crude form is in biotechnological processes. Xanthan gum is a commercial gum used primarily in the pharmaceutical and food industries as thickener, emulsifier and stabilizer. It is synthetized by species of the bacterium Xanthomonas generally from glucose. However, current research shows that species of this bacterium have the capacity to grow and synthesize the gum using glycerin from biodiesel. The aim of this study was to produce xanthan gum using glycerin from biodiesel production in medium with different nitrogen content, named complex and simple media. The kinetics of fermentation in simple medium showed a twofold increase in gum production (3.16 kg.m-3) compared to the one in complex medium (1.46 kg.m-3) after 120 hours. The gum generated in this study showed chemical and rheological characteristics of xanthan gum. Glucose supplementation did not show an increase in xanthan production but did increase the consistency index and the behavioral index of solutions of this gum.(AU)


Assuntos
Xanthomonas , Biocombustíveis/análise , Glicerol , Biotecnologia , Glucose
9.
J. venom. anim. toxins incl. trop. dis ; 25: e20190027, 2019. tab, graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1040382

Resumo

Bone tissue repair remains a challenge in tissue engineering. Currently, new materials are being applied and often integrated with live cells and biological scaffolds. The fibrin biopolymer (FBP) proposed in this study has hemostatic, sealant, adhesive, scaffolding and drug-delivery properties. The regenerative potential of an association of FBP, biphasic calcium phosphate (BCP) and mesenchymal stem cells (MSCs) was evaluated in defects of rat femurs. Methods: Adult male Wistar rats were submitted to a 5-mm defect in the femur. This was filled with the following materials and/or associations: BPC; FBP and BCP; FBP and MSCs; and BCP, FBP and MSCs. Bone defect without filling was defined as the control group. Thirty and sixty days after the procedure, animals were euthanatized and subjected to computed tomography, scanning electron microscopy and qualitative and quantitative histological analysis. Results: It was shown that FBP is a suitable scaffold for bone defects due to the formation of a stable clot that facilitates the handling and optimizes the surgical procedures, allowing also cell adhesion and proliferation. The association between the materials was biocompatible. Progressive deposition of bone matrix was higher in the group treated with FBP and MSCs. Differentiation of mesenchymal stem cells into osteogenic lineage was not necessary to stimulate bone formation. Conclusions: FBP proved to be an excellent scaffold candidate for bone repair therapies due to application ease and biocompatibility with synthetic calcium-based materials. The satisfactory results obtained by the association of FBP with MSCs may provide a more effective and less costly new approach for bone tissue engineering.(AU)


Assuntos
Animais , Ratos , Biopolímeros , Matriz Óssea , Fibrina , Células-Tronco Mesenquimais , Produtos Biológicos
10.
J. Venom. Anim. Toxins incl. Trop. Dis. ; 25: e.20190027, Nov. 4, 2019. ilus, tab, graf
Artigo em Inglês | VETINDEX | ID: vti-24651

Resumo

Background:Bone tissue repair remains a challenge in tissue engineering. Currently, new materials are being applied and often integrated with live cells and biological scaffolds. The fibrin biopolymer (FBP) proposed in this study has hemostatic, sealant, adhesive, scaffolding and drug-delivery properties. The regenerative potential of an association of FBP, biphasic calcium phosphate (BCP) and mesenchymal stem cells (MSCs) was evaluated in defects of rat femurs.Methods:Adult male Wistar rats were submitted to a 5-mm defect in the femur. This was filled with the following materials and/or associations: BPC; FBP and BCP; FBP and MSCs; and BCP, FBP and MSCs. Bone defect without filling was defined as the control group. Thirty and sixty days after the procedure, animals were euthanatized and subjected to computed tomography, scanning electron microscopy and qualitative and quantitative histological analysis.Results:It was shown that FBP is a suitable scaffold for bone defects due to the formation of a stable clot that facilitates the handling and optimizes the surgical procedures, allowing also cell adhesion and proliferation. The association between the materials was biocompatible. Progressive deposition of bone matrix was higher in the group treated with FBP and MSCs. Differentiation of mesenchymal stem cells into osteogenic lineage was not necessary to stimulate bone formation.Conclusions:FBP proved to be an excellent scaffold candidate for bone repair therapies due to application ease and biocompatibility with synthetic calcium-based materials. The satisfactory results obtained by the association of FBP with MSCs may provide a more effective and less costly new approach for bone tissue engineering.(AU)


Assuntos
Animais , Ratos , Biopolímeros/uso terapêutico , Regeneração Óssea , Adesivo Tecidual de Fibrina/uso terapêutico , Células-Tronco
11.
Tese em Português | VETTESES | ID: vtt-220495

Resumo

Estímulos à pesquisa de novos materiais impulsionam o setor das ciências biomédicas na procura de compostos aplicados à medicina regenerativa. A gelatina apresenta boas propriedades em processos cicatriciais além de ser biocompatível com a maioria das estruturas celulares sendo possível sua aplicação em diversas especialidades médicas. Assim como a gelatina, filmes poliméricos obtidos a partir deste precursor apresentam boas propriedades mecânicas e biocompatibilidade, ampliando a sua gama de aplicações. Este trabalho tem como objetivo aplicar um biomaterial de gelatina extraído das escamas de tilápia do Nilo (Oreochromis niloticus), e avaliar a atuação in vitro pela porcentagem de degranulação de neutrófilos de cães, comparando os resultados com grupos de amostras de neutrófilos estimulados pela N-formil-metionil-leucil-fenilalanina (fMLP). Para execução desse estudo foram coletadas amostras de sangue de cães clinicamente hígidos e divididas em oito grupos, sendo um controle negativo (fMLP sem a presença de polímero); três condições com a adição de polímero de gelatina de massas diferentes, e outras três condições com adição do polímero de gelatina com fMLP. Para avaliar o estresse oxidativo dos neutrófilos gerado pelo polímero foi utilizado o método de redução do corante tetrazólio nitroazul (NBT) e a sua quantificação deu-se pela técnica de espectrofotometria na região do ultravioleta e do visível (UV/VIS). Os resultados mostraram que na maioria das condições apresentadas a diferentes concentrações de polímero de gelatina avaliado não produziram estresse oxidativo demonstrando assim baixo potencial de citotoxicidade.


Incentives for the search for new materials drive the biomedical sciences sector to search for compounds applied to regenerative medicine. Gelatin has good properties in healing process as well as being biocompatible with most cell structures, making it possible to be applied in several medical specialties. Like gelatin, the polymeric films obtained from this precursor present good mechanical properties and biocompatibility, expanding its range of applications. This project aims to apply a gelatins biomaterial extracted from Nile tilapia (Oreochromis niloticus) scales and evaluate in vitro performance by the percentage of neutrophil degranulation in dogs comparing the results with samples groups neutrophils stimulated by N-Formylmethionineleucyl-phenylalanine (fMLP). To qualify this study, blood samples were collected from dogs and divided into eight groups, being a negative control (fMLP - without the presence of polymer); three conditions with the addition of gelatin polymer of different masses, and three other conditions with the addition of gelatin polymer with fMLP. To evaluate the neutrophils oxidative stress generated by the polymer, the method of reduction of the nitro-blue tetrazolium (NBT) dye will be used and its quantification will be done using the spectrophotometry method in the ultraviolet and visible (UV / Vis) region. The results showed that in most of the conditions presented to different concentrations of gelatin polymer evaluated, they did not produce oxidative stress, thus demonstrating low potential for cytotoxicity

12.
Tese em Português | VETTESES | ID: vtt-222000

Resumo

O parasitismo por nematoides gastrintestinais (NGI) é uma grave ameaça a ovinocaprinocultura e com o aparecimento e disseminação da resistência anti-helmíntica (RA), novas alternativas de controle são necessárias. O óleo essencial de Eucalyptus staigeriana (OEEs) apresenta atividade anti-helmíntica, e o desenvolvimento de formulações visando o seu encapsulamento usando matriz de alginato de sódio (ALG) pode ser vantajoso para aumentar sua estabilidade e eficácia. Objetivando-se desenvolver emulsões de ALG e OEEs para o controle de NGI de pequenos ruminantes, a metodologia foi realizada em três fases. Na fase 1, cujo objetivo foi caracterizar uma população de Haemonchus contortus, nomeada Caucaia, quanto à RA, realizou-se a comparação entre testes fenotípicos de eclosão de ovos (TEO), desenvolvimento larvar (TDL) e redução de ovos nas fezes (TRCOF) e genotípico por qPCR para benzimidazois (BZs) e levamisol (LEV). Houve concordância entre TEO, TRCOF e qPCR para BZs, e entre TDL e qPCR para LEV. A população Caucaia foi considerada resistente a BZs, lactonas macrocíclicas, LEV e suspeita para monepantel. Na fase 2, objetivou-se desenvolver emulsões de ALG e OEEs, caracterizá-las e avaliar seus efeitos in vitro sobre eclosão de ovos e desenvolvimento larvar de H. contortus. Quatro emulsões foram preparadas com proporções variadas de Tween 80, OEEs e ALG 4%, caracterizadas físico-quimicamente e avaliadas no TEO e TDL. As emulsões foram estáveis, com tamanho de partícula predominantemente nanométrico e potencial zeta negativo. As emulsões foram mais efetivas que o OEEs no TEO, com concentração efetiva 50% (CE50) de 0,088 a 0,150 mg/mL para as emulsões e 0,308 mg/mL para OEEs. No TDL, emulsões e OEEs foram semelhantes, com CE50 variando de 3,91 a 4,60 mg/mL para emulsões e 4,17 mg/mL para OEEs. Portanto, emulsões de ALG e OEEs foram produzidas com sucesso, sendo a emulsão 2 (E2), com menor razão Tween 80/OEEs e ALG/OEEs, considerada a melhor e com potencial para o controle alternativo de H. contortus. Na fase 3, objetivou-se avaliar E2 in vitro contra H. contortus adultos, sua toxicidade aguda e atividade in vivo contra NGI. Foram realizados os testes de motilidade do adulto (TMA), avaliação por microscopia eletrônica de varredura (MEV) e confocal de varredura a laser (MCVL). A dose letal 50% (DL50) de E2 foi verificada e o TRCOF foi realizado contra NGI da população Caucaia. No TMA, OEEs e E2 inibiram a motilidade de H. contortus e nas concentrações de 0,4 e 0,6 mg/mL, E2 foi mais efetiva que o OEEs. As imagens de MEV e de MCVL demonstraram alterações estruturais, principalmente, enrugamento de cutícula. A DL50 estimada da emulsão foi superior a 2.000 mg/kg. No TRCOF, a eficácia do OEEs e de E2 foram similares, com 54,2% de redução no opg pós-tratamento. Portanto, E2 demonstrou efeito promissor contra H. contortus adultos in vitro, segurança toxicológica e atividade contra NGI in vivo. Dessa forma, foi possível produzir e caracterizar, de forma bem-sucedida, emulsões de ALG e OEEs, que demonstraram estabilidade e atividade anti-helmíntica contra NGI de pequenos ruminantes, com potencial para aplicação em futuros esquemas de tratamento alternativo.


Parasitism by gastrointestinal nematodes (GIN) is a serious threat to sheep and goat farming and due to emergence and spread of anthelmintic resistance (AR), new control alternatives are required. The essential oil of Eucalyptus staigeriana (EsEO) has anthelmintic activity, so the development of formulations aimed at its encapsulation using sodium alginate matrix (ALG) can be advantageous to increase its stability and effectiveness. Aiming to develop emulsions of ALG and EsEO to control GIN in small ruminants, the methodology was developed in three phases. In phase 1, whose objective was to characterize a population of Haemonchus contortus, named Caucaia, regarding AR, a comparison was made between phenotypic tests of egg hatch (EHT), larval development (LDT) and fecal egg reduction (FECRT) and genotypic by qPCR for benzimidazoles (BZs) and levamisole (LEV). There was agreement between EHT, FECRT and qPCR for BZs, and between LDT and qPCR for LEV. The Caucaia population was considered resistant to BZs, macrocyclic lactones, LEV and suspected for monepantel. In phase 2, the aim was to develop emulsions of ALG and EsEO, characterize them and evaluate their in vitro effects on egg hatching and larval development of H. contortus. Four emulsions were prepared by varying proportions between Tween 80, EsEO and 4% ALG, physicochemically characterized and evaluated on EHT and LDT. The emulsions were stable, with predominantly nanometric particle size and negative zeta potential. The emulsions were more effective than EsEO in EHT, with effective concentration 50% (EC50) ranging from 0.088 to 0.150 mg/mL for the emulsions and 0.308 mg/mL for EsEO. In LDT, emulsions and EsEO were similar, with EC50 ranging from 3.91 to 4.60 mg/mL for emulsions and 4.17 mg/mL for EsEO. Therefore, ALG and EsEO emulsions were successfully produced, and emulsion 2 (E2), with low levels of the ratio between Tween 80/EsEO and ALG/EsEO was considered the best and with potential for alternative control of H. contortus. In phase 3, the aim was to evaluate E2 in vitro against adult H. contortus, its acute toxicity and in vivo activity against GIN. Adult worm motility test (AWMT) was performed, evaluation by scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM). The lethal dose 50% (LD50) of E2 was assessed and FECRT was performed against the Caucaia population GIN. In AWMT, EsEO and E2 inhibited the motility of H. contortus and at concentrations 0.4 and 0.6 mg/mL, E2 was more effective than EsEO. SEM and CLSM images showed structural changes, mainly cuticle wrinkling. The LD50 of the emulsion was estimated to be greater 2,000 mg/kg. In FECRT, the efficacy of EsEO and E2 were similar, with a 54.2% reduction in epg post-treatment. Therefore, E2 showed promising effect against adult H. contortus in vitro, toxicological safety and activity against GIN in vivo. In this way, it was possible to successfully produce and characterize emulsions of ALG and EsEO, which demonstrated stability and anthelmintic activity gainst GIN of small ruminants, with potential for application in future alternative treatment schemes.

13.
Tese em Português | VETTESES | ID: vtt-218749

Resumo

Propôs-se com este trabalho avaliar a adição do Líquido da Castanha de Caju técnico (LCCt) e da Quitosana como aditivos naturais para bovinos confinados rebendo dieta de milho grão inteiro. Foram utilizados cinco (5) novilhos mestiços canulados no rúmen com peso médio de 350 kg, distribuídos aleatoriamente em delineamento em quadrado latino 5x5 e mantidos em baias individuais, recebendo uma dieta constituida de 85% de milho grão inteiro e 15% de pellet proteico-mineral-vitaminico. As dietas experimentais foram acrescidas de monensina (25 mg/Kg de MS); quitosana (375 mg/Kg de MS); LCCt(500mg/kg de MS); quitosana + LCCt (375mg + 500mg/kg de MS); além da dieta controle. Os animais alimentados com a associação de LCCt+QUI apresentaram menor consumo de MS (6.60 Kg/dia) e PB (0.872 Kg/dia) e maior coeficiente de digestibilidade em comparação ao tratamento com monensina. A inclusão de LCCt+QUI na dieta levou a uma redução na concentração molar de acetato e uma maior produção de propionato. Não houve efeito para a inclusão dos aditivos, na síntese de nitrogênio, proteína microbiana e nas concentrações de ureia e creatinina no sangue e na urina. A associação dos aditivos LCCt+QUI promoveu redução no consumo de nitrogênio e balanço de nitrogênio em relação ao tratamento com monensina. A associação entre quitosana e líquido da castanha de caju, apresentou os melhores resultados em dietas de milho grão inteiro, podendo substituir a monensina.


The aimed of this work was to evaluate the addition of technical Cashew Nut Liquid (CNLt) and Chitosan as natural additives for confined cattle fed whole grain corn diet. Five (5) rumen-cannulated crossbred steers with an average weight of 350 kg were used, randomly distributed in a 5x5 Latin square design and kept in individual pens, receiving a diet consisting of 85% whole grain corn and 15% protein mineral-vitamin pellet. The xperimental diets were added with monensin (25 mg/kg of DM); chitosan (375 mg/kg MS); CNLt (500mg/kg MS); chitosan + CNLt (375mg + 500mg/kg of MS); in addition to the control diet. The animals fed with the association of CNLt+CHI had lower consumption of DM (6.60 Kg/day) and CP (0.872 Kg/day) and higher coefficient of digestibility compared to the treatment with monensin. The inclusion of CNLt+CHI in the diet led to a reduction in the molar concentration of acetate and a greater production of propionate. There was no effect for the inclusion of additives, on the synthesis of nitrogen, microbial protein and on the concentrations of urea and creatinine in blood and urine. The association of CNLt+CHI additives promoted a reduction in nitrogen consumption and nitrogen balance in relation to the treatment with monensin. The association between technical cashew nut liquid and chitosan showed the best results in whole grain maize diets, being able to replace monensin.

14.
Braz. J. Microbiol. ; 46(2): 407-413, Apr.-Jun. 2015. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-481399

Resumo

The objective of this study was to evaluate the exopolysaccharide (EPS) production by Rhizobium leguminosarum cultivated in wastewater generated by oil companies (WWOC1 and WWOC2) and fish processing industry (WWFP). The results obtained in Erlenmeyer flasks indicated that the rhizobial strain grew well in industrial wastewater. Generally, wastewater composition affected the growth and the EPS production. WWFP allowed good bacterial growth similar to that obtained with the standard medium (YMB). During growth, various quantities of EPS were produced and yields varied depending on the media. Growing in YMB, EPS production did not exceed 9.7 g/L obtained after 72 h of growth. In wastewater, the maximum EPS value reached 11.1 g/L obtained with the fish processing wastewater, after 72 h of growth. The use of a mixture of the oil company wastewater (WWOC2) and the fish processing wastewater (WWFP) as culture medium affected not only the rhizobial strain growth, but also EPS production. The highest EPS (42.4 g/L, after 96 h of culture) was obtained using a ratio of WWFP and WWOC2 of 50:50 (v:v). Therefore, this work shows the ability of Rhizobium leguminosarum, growing in industrial wastewater as new economic medium, to produce EPS. This biopolymer could be applied in enormous biotechnological areas.(AU)


Assuntos
Polissacarídeos Bacterianos/metabolismo , Rhizobium leguminosarum/crescimento & desenvolvimento , Águas Residuárias/microbiologia , Indústria Alimentícia , Resíduos Industriais , Indústria de Petróleo e Gás
15.
Tese em Português | VETTESES | ID: vtt-212301

Resumo

A pesquisa propôs avaliar a adição do Líquido da Castanha de Caju (LCC) e Quitosana como aditivos naturais para bovinos suplementados a pasto. Foram utilizados cinco (5) novilhos mestiços canulados no rúmen com peso médio de 300 kg, distribuídos aleatoriamente em delineamento em quadrado latino 5x5 e mantidos em piquetes individuais de Urochloa brizantha, suplementados na proporção de 0,4% do peso corporal com um suplemento contendo proteína bruta. As dietas experimentais fornecidas foram: 1) Suplementação mineral (Controle); 2) Suplementação proteica; 3) Suplementação proteica com adição de quitosana na dosagem de 900mg/Kg de MS; 4) Suplementação proteica com adição de LCC, na dosagem de 600mg/kg de MS; e 5) Suplementação proteica, com adição de quitosana mais LCC (900mg + 600mg/ kg de MS). Os animais suplementados com LCCt apresentaram menor consumo de pasto, MS e PB em relação aos animais que receberam apenas suplementação. Os novilhos suplementados com LCCt*QUIT apresentaram maior consumo de suplemento (P = 0,004) e proporcionou maior consumo de PB (1,015 kg/dia). A inclusão de quitosana na dieta levou a uma redução (P<0,05) na concentração molar de acetato e uma maior produção de propionato (P<0,03). Os animais que receberam LCCt em sua dieta apresentaram maiores valores sobre síntese de nitrogênio e proteína microbiana (P = 0,004). A associação dos aditivos nas dosagens de 900mg + 600mg/kg promoveu maior consumo de nitrogênio (P = 0,126) e balanço de nitrogênio (P = 0,201). O líquido da castanha de caju mostrou-se eficiente sobre a digestibilidade e síntese de proteína microbiana dos animais. A associação dos aditivos promoveu maior consumo de suplemento e balanço de nitrogênio. A inclusão de quitosana na dieta le


The research proposed to evaluate the addition of Cashew Nut Liquid (LCC) and Chitosan as natural additives for pasture supplemented cattle. Five (5) rumen cannulated crossbred steers with an average weight of 300 kg were randomly distributed in a 5x5 Latin square design and kept in individual paddocks of Urochloa brizantha, supplemented with 0.4% of body weight with a supplement containing crude protein. The experimental diets provided were: 1) Mineral supplementation (Control); 2) protein supplementation; 3) Protein supplementation with addition of chitosan in the dosage of 900mg / kg DM; 4) Protein supplementation with the addition of LCC, at a dosage of 600mg / kg DM; and 5) Protein supplementation with the addition of chitosan plus LCC (900mg + 600mg / kg DM). The animals supplemented with CCT presented lower consumption of pasture, DM and CP compared to animals that received only supplementation. The steers supplemented with CCT * QUIT presented higher supplement intake (P = 0.004) and higher CP intake (1.015 kg / day). Inclusion of chitosan in the diet led to a reduction (P <0.05) in the acetate molar concentration and a higher propionate production (P <0.03). The animals that received CCT in their diet had higher values on nitrogen synthesis and microbial protein (P = 0.004). The association of additives at dosages of 900mg + 600mg / kg promoted higher nitrogen consumption (P = 0.126) and nitrogen balance (P = 0.201). The cashew nut liquid was efficient on the digestibility and synthesis of microbial protein of the animals. The association of additives promoted higher supplement intake and nitrogen balance. Inclusion of chitosan in the diet led to a reduction in molar acetate concentration and a higher production of propionate.

16.
Ci. Rural ; 43(7)2013.
Artigo em Português | VETINDEX | ID: vti-708388

Resumo

The aim of this research was to evaluate the process of bone regeneration in rabbits by the use of hydroxyapatite and chitosan only and associated with bone marrow. Twenty male and female rabbits, New Zealand breed and weighing in average 3.0±0.4kg were used. Animals were randomly divided according with two experimental moments, being 10 animals euthanized 30 days after surgery, and 10 euthanized 60 days after surgery. Four implants that constituted the groups were used. Materials were introduced into the proximal (MP) and distal metaphysis (MD) of each femur, so that chitosan was introduced into the MP and hydroxyapatite into the MD of the left limb, and in the right limb bone marrow was added beyond the implants. At the comparative descriptive histological evaluation, it was found that the QUI and QUIMO groups in both periods stimulated more pronounced reactions and accelerated bone repair. In morphometric analysis, QUI and QUIMO groups differed statistically from the other, has been shown greater bone formation (P 0.05).


O objetivo do presente trabalho foi avaliar o processo de regeneração óssea em coelhos através da utilização da hidroxiapatita e da quitosana isoladas e associadas à medula óssea. Foram utilizados 20 coelhos adultos, de ambos os sexos, da raça Nova Zelândia e pesando em média 3,0±0,4kg. Os animais foram divididos ao acaso de acordo com dois momentos experimentais, sendo que 10 animais foram submetidos à eutanásia 30 dias após a cirurgia, e 10, 60 dias após a cirurgia. Foram utilizados quatro implantes que constituíram os grupos. Os materiais foram introduzidos em defeitos criados cirurgicamente na metáfise proximal (MP) e distal (MD) de cada fêmur, de modo que a quitosana foi introduzida na MP e a hidroxiapatita na MD do membro esquerdo e, no membro direito, além dos implantes, foi adicionada medula óssea. Na avaliação histológica descritiva comparativa, constatou-se que os grupos QUI e QUIMO, em ambos os momentos estudados, estimularam reações mais acentuadas e aceleraram o reparo ósseo. Na análise morfométrica, os grupos QUI e QUIMO diferiram estatisticamente dos outros grupos, tendo sido observada maior formação óssea (P 0,05).

17.
Artigo em Português | LILACS-Express | VETINDEX | ID: biblio-1479453

Resumo

The aim of this research was to evaluate the process of bone regeneration in rabbits by the use of hydroxyapatite and chitosan only and associated with bone marrow. Twenty male and female rabbits, New Zealand breed and weighing in average 3.0±0.4kg were used. Animals were randomly divided according with two experimental moments, being 10 animals euthanized 30 days after surgery, and 10 euthanized 60 days after surgery. Four implants that constituted the groups were used. Materials were introduced into the proximal (MP) and distal metaphysis (MD) of each femur, so that chitosan was introduced into the MP and hydroxyapatite into the MD of the left limb, and in the right limb bone marrow was added beyond the implants. At the comparative descriptive histological evaluation, it was found that the QUI and QUIMO groups in both periods stimulated more pronounced reactions and accelerated bone repair. In morphometric analysis, QUI and QUIMO groups differed statistically from the other, has been shown greater bone formation (P 0.05).


O objetivo do presente trabalho foi avaliar o processo de regeneração óssea em coelhos através da utilização da hidroxiapatita e da quitosana isoladas e associadas à medula óssea. Foram utilizados 20 coelhos adultos, de ambos os sexos, da raça Nova Zelândia e pesando em média 3,0±0,4kg. Os animais foram divididos ao acaso de acordo com dois momentos experimentais, sendo que 10 animais foram submetidos à eutanásia 30 dias após a cirurgia, e 10, 60 dias após a cirurgia. Foram utilizados quatro implantes que constituíram os grupos. Os materiais foram introduzidos em defeitos criados cirurgicamente na metáfise proximal (MP) e distal (MD) de cada fêmur, de modo que a quitosana foi introduzida na MP e a hidroxiapatita na MD do membro esquerdo e, no membro direito, além dos implantes, foi adicionada medula óssea. Na avaliação histológica descritiva comparativa, constatou-se que os grupos QUI e QUIMO, em ambos os momentos estudados, estimularam reações mais acentuadas e aceleraram o reparo ósseo. Na análise morfométrica, os grupos QUI e QUIMO diferiram estatisticamente dos outros grupos, tendo sido observada maior formação óssea (P 0,05).

18.
Braz. j. microbiol ; 44(2): 539-549, 2013.
Artigo em Inglês | VETINDEX | ID: vti-961

Resumo

The present study aimed at developing a strategy to improve the volumetric production of PHAs by Pseudomonas fluorescens S48 using waste frying oil (WFO) as the sole carbon source. For this purpose, several cultivations were set up to steadily improve nutrients supply to attain high cell density and high biopolymer productivity. The production of PHAs was examined in a 14 L bioreactor as one-stage batch, two-stage batch, and high-cell-density fed-batch cultures. The highest value of polymer content in one-stage bioreactor was obtained after 60 h (33.7%). Whereas, the two-stage batch culture increased the polymer content to 50.1% after 54 h. High-cell-density (0.64 g/L) at continuous feeding rate 0.55 mL/l/h of WFO recorded the highest polymer content after 54 h (55.34%). Semi-scale application (10 L working volume) increased the polymer content in one-stage batch, two-stage batch and high cell density fed-batch cultures by about 12.3%, 5.8% and 11.3%, respectively, as compared with that obtained in 2 L fermentation culture. Six different methods for biopolymer extraction were done to investigate their efficiency for optimum polymer recovery. The maximum efficiency of solvent recovery of PHA was attained by chloroform-hypochlorite dispersion extraction. Gas chromatography (GC) analysis of biopolymer produced by Pseudomonas fluorescens S48 indicated that it solely composed of 3-hydrobutyric acid (98.7%). A bioplastic film was prepared from the obtained PHB. The isolate studied shares the same identical sequence, which is nearly the complete 16S rRNA gene. The identity of this sequence to the closest pseudomonads strains is about 98-99%. It was probably closely related to support another meaningful parsiomony analysis and construction of a phylogenetic tree. The isolate is so close to Egyptian strain named EG 639838.(AU)


Assuntos
Pseudomonas fluorescens , Biopolímeros , Poli-Hidroxialcanoatos , Técnicas de Genotipagem , Reatores Biológicos
19.
Tese em Português | VETTESES | ID: vtt-216128

Resumo

As novas tendencias do mercado consumidor levaram o setor alimenticio a concentrar esforcos no desenvolvimento de filmes e revestimentos comestiveis a base de polimeros naturais em substituicao as embalagens plasticas convencionais. Os filmes e revestimentos comestiveis de quitosana e oleos essenciais podem ser uma excelente alternativa para manter a qualidade e frescor do camarao durante armazenamento. O presente estudo teve por objetivo avaliar as propriedades fisicas e mecanicas de filmes a base de quitosana e oleos essenciais (tangerina, limao, cravo, louro, manjericao, hortela), as potencialidades antimicrobianas dos revestimentos dos mesmos componentes dos filmes, alem de avaliar a eficacia de revestimentos de quitosana e oleos essenciais de limao e tangerina em camarao (Litopenaeus vannamei) congelado atraves de analises quimicas, fisico-quimicas e microbiologicas. Os filmes foram caracterizados quanto a solubilidade, permeabilidade ao vapor de agua (PVA), cor, opacidade, resistencia a tracao, elongacao na ruptura e modulo de elasticidade e apresentaram diferencas significativas (p<0,05) entre os tratamentos. A atividade antimicrobiana dos revestimentos foi testada frente a quatro cepas padroes de bacterias e todos os revestimentos apresentaram acao antimicrobiana. Foram realizadas analises de composicao quimica, pH, bases volateis totais (BVT), trimetilamina (TMA), substancias reativas ao acido tiobarbiturico (TBARS), e microbiologicas (contagem total de mesofilas e psicrotroficas, Vibrio spp e Staphylococus congulase positiva e coliformes termotolerantes) em amostras de camarao submetidas a cinco tratamentos: controle (C), glaciamento (G), revestimento de quitosana (Q), revestimento de quitosana + oleo essencial de tangerina (QT) e revestimento de quitosana + oleo essencial de limao (QL) durante 180 dias de armazenamento. Os valores de pH, TBARS, BVT e TMA das amostras de camarao apresentaram diferencas significativas (p>0,05) entre os tratamentos. As amostras revestidas (Q, QT e QL) apresentaram as menores contagens de bacterias mesofilas e psicrotroficas e os valores para coliformes termotolerantes, Staphylococcus coagulase positiva e Vibrio spp apresentaram-se dentro da legislacao vigente durante o periodo de armazenamento. Os filmes e revestimentos comestiveis a base de quitosana e oleos essenciais apresentaram excelentes propriedades fisicas e antimicrobianas e podem ser utilizados de forma promissora para manter a qualidade de camarao congelado devido a sua natureza nao toxica, biodegradavel e atividade antimicrobiana.


New consumer market trends have led the food industry to focus on the development of natural polymer-based edible films and coatings instead of conventional plastic packaging. Thus the films and edible coatings of chitosan and essential oils can be an excellent alternative to maintain the quality and freshness of the shrimp during storage.The objective of this study was to evaluate the physical and properties of chitosan and essential oils (clove, Peppermint, lemon, laurel, basil and tangerine), the antimicrobial potential of coatings of the same components of the films, and to evaluate the efficacy of chitosan coatings and essential oils in shrimp (Litopenaeus vannamei) frozen through chemical, physicochemical and microbiological analyzes. The films were characterized in terms of solubility, water vapor permeability (WVP), color, opacity, tensile strength, elongation at break and elastic modulus and presented significant differences (p<0.05) between the treatments. The antimicrobial activity of the coatings was tested against four standard strains of bacteria and all the coatings presented antimicrobial action. Analyzes of chemical composition, pH, total volatile bases (TVB), trimethylamine (TMA), thiobarbituric acid reactive substances (TBARS), and microbiological (total mesophilic and psychrotrophic counts), Vibrio spp. and Staphylococus congulase positive and thermotolerant coliforms in shrimp samples submitted to five treatments: control (C), glazing (G), chitosan coating (Q), chitosan coating + tangerine essential oil (QT) and chitosan coating + lemon essential oil (QL) during 180 days of storage. The pH, TBARS, TVB and TMA values of the shrimp samples presented significant differences (p<0.05) Coated samples (Q, QT and QL) showed the counts lowest of mesophilic and psychrotrophic bacteria. Vibrio spp. in all the treatments presented counts under the current legislation. For thermotolerant coliforms and Staphylococcus coagulase positive the C and G treatments presented values above the legislation. Films and edible coatings of chitosan and essential oils have good physical and antimicrobial properties and can be used to maintain the quality of frozen shrimp because of their non-toxic, biodegradable nature and antimicrobial activity.

20.
Tese em Português | VETTESES | ID: vtt-207941

Resumo

O uso indiscriminado dos plásticos tem gerado graves problemas ambientais de acúmulo de material na natureza, poluição das águas, além de ser proveniente do petróleo, um recurso não renovável. Isso tem causado preocupação e, portanto, os cientistas e indústrias vêm buscando alternativas ao uso desses materiais, como por exemplo o emprego de materiais naturais e/ou biodegradáveis e o aproveitamento de subprodutos desperdiçados. O amido é um polímero natural que tem aspectos que o tornam promissor, como sua biodegradabilidade, baixo custo e disponibilidade. Para prolongar a vida útil dos alimentos, investigou-se o amido como matéria prima para a produção de filmes biodegradáveis e revestimentos comestíveis ativos. Além de atuar como barreira a gases e como proteção mecânica, as embalagens também podem carrear substâncias ativas como antioxidantes, antimicrobianos, entre outros. Foi estudado o efeito da incorporação de (0,3; 0,5 e 1,0) g de a-tocoferol/100 g de dispersão filmogênica nas propriedades morfológicas, mecânicas, ópticas, de superfície, de barreira ao vapor dágua e à luz UV/Visível e antioxidantes dos filmes de amido de semente de jaca. A adição de a-tocoferol aumentou a resistência à tração e o módulo de elasticidade nos filmes com até 0,5% de atocoferol. Também aumentou a barreira ao vapor dágua, possivelmente devido à natureza hidrofóbica do a-tocoferol e ao efeito de tortuosidade causado por ele na matriz polimérica, embora a solubilidade em água não tenha diferido significativamente entre os filmes. O a-tocoferol proporcionou aumento na barreira contra a luz UV, especialmente nos comprimentos de onda entre (200 e 310) nm. A opacidade e o parâmetro de cor b* aumentaram significativamente, o que significa que a incorporação de a-tocoferol tornou os filmes mais opacos e amarelados. A hidrofobicidade da superfície aumentou significativamente (p < 0,05) com adição de a-tocoferol, principalmente no filme com 0,5% de atocoferol. A capacidade antioxidante aumentou significativamente com adição de até 0,5% de a-tocoferol. O filme controle (sem a-tocoferol) não apresentou capacidade antioxidante. Concluiu-se que o material de amido de semente de jaca incorporado de a-tocoferol tem potencial para ser usado como revestimento ativo para alimentos com alto teor de gordura. Entre as formulações produzidas, a de 0,5% de a-tocoferol foi a melhor, porque apresentou atividade antioxidante tão boa quanto o filme 1,0% de a-tocoferol e propriedades mais interessantes, como a microestrutural, mecânica, óptica e de superfície.


Indiscriminate use of plastics has been generating environmental problems, like accumulation of materials, water pollution, as well as depleting a non-renewable resource (crude oil). This has been causing concern, therefore scientists and industries are seeking alternatives for these materials, for example, the employment of natural and/or biodegradable materials and the reuse of wasted byproducts. Starch is a natural polymer with many promising aspects, like its biodegradability, low cost and availability. Aiming at prolonging shelf-life of food products, starch has been investigated as a feedstock for development of edible active films and coatings. Besides acting as a barrier against gases and as mechanical protection, packages also may carry active substances (antioxidants, antimicrobials, etc.). The effects of the incorporation of (0.3; 0.5 and 1.0) g a-tocopherol/100 g filmogenic dispersion on the morphological, mechanical, optical, surface, water vapor permeability, barrier to UV/Visible light and antioxidant properties of jackfruit seed starch films were studied. Addition of a-tocopherol increased the tensile strength and the elastic modulus up to 0.5%. It also increased the water vapor barrier, possibly due to a-tocopherols hydrophobic nature and because it caused a tortuosity effect in the polymer matrix, although the film solubility was not significantly affected. a-tocopherol nimproved the UV light barrier, especially in the wavelengths between (200 and 310) nm. The opacity and the color parameter b* increased significantly, which means that films with a-tocopherol became more opaque and yellowish. Surface hydrophobicity increased with the incorporation of a-tocopherol, especially for the 0.5% a-tocopherol film. The antioxidant activity increased significantly up to 0.5% a-tocopherol. The film without a-tocopherol presented no antioxidant capacity. Therefore, jackfruit seed starch films incorporated with a-tocopherol have potential to be used as edible active coatings for high fat content foods. Between the formulations produced, the one with 0.5% of a-tocopherol was the best, because it presented an antioxidant activity similar to the film with 1.0% of atocopherol and superior characteristics, like microstructural, mechanical, optical and surface properties.

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