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1.
São Paulo; s.n; s.n; 2021. 123 p. tab, graf, ilus.
Thesis in Portuguese | LILACS | ID: biblio-1380006

ABSTRACT

Diante das exigências crescentes das agências regulatórias do mundo todo quanto à redução/eliminação de ácidos graxos trans nos alimentos industrializados, bem como da conscientização do consumidor sobre a relação entre alimentação e saúde, o desenvolvimento de alternativas mais saudáveis aos óleos parcialmente hidrogenados e a outras fontes lipídicas com alto grau de saturaçã o se faz necessário. O oleogel, um sistema composto por um óleo preso em uma rede tridimensional formada por um agente estruturante, se apresenta como uma solução promissora. Dentre os diversos agentes estruturantes, as ceras vegetais se destacam por sua excelente capacidade de gelificação de óleos. Contudo, apresentam uma desvantagem sob o aspecto sensorial, pois podem conferir cerosidade e sabor residual desagradável aos alimentos. Com o objetivo de viabilizar o uso das ceras como agentes estruturantes em oleogéis face ao seu excelente desempenho tecnológico, este projeto propõe o estudo e a aplicação de oleogéis à base de óleo de soja (SBO) estruturado com ceras de farelo de arroz (RBW) a 2 e 4 % (m/m) ou carnaúba (CBW) a 3 e 6% (m/m), isoladamente. As matérias-primas foram caracterizadas e o comportamento de gelificação de cada cera foi avaliado por análises de textura por penetração de cone, estabilidade à perda de óleo por centrifugação, energia coesiva por parâmetro de solubilidade de Hansen (HSP) e comportamento de cristalização e fusão por calorimetria exploratória diferencial (DSC). Os resultados mostraram que ambas as ceras são capazes de formar oleogéis estruturalmente estáveis, contudo, o oleogel com 2% de RBW apresentou maior firmeza a 20 °C (190,4 gf/cm2) do que o oleogel com 6% de CBW a 5 °C (186,1 gf/cm2). Ao final de 5 dias, a capacidade de retenção de óleo do oleogel preparado com RBW foi de 100% às concentrações de 2 e 4% (m/m), contra 61 e 99,3% do oleogel elaborado com CBW às concentrações de 3 e 6% (m/m), respectivamente. Esses resultados podem ser explicados pela diferença entre as energias coesivas, ou seja, do grau de interação molecular entre o solvente e o soluto de cada oleogel. De acordo com os resultados de distância, que prevê se o gel formado será forte, fraco ou se não haverá formação de gel, o soluto CBW apresentou menor interação com o óleo (3,3 MPa1/2) do que o soluto RBW (3,7 MPa1/2). Os oleogéis foram aplicados como ingredientes em diferentes formulações de cream cheese, que foram analisados quanto a diferentes parâmetros de textura e esses resultados foram comparados a uma referência comercial. Nenhuma das amostras produzidas obteve resultados de textura estatisticamente iguais aos do cream cheese comercial (CC), o que pode ser explicado pelas diferenças de formulação e processamento dos produtos. Face aos resultados para textura e estabilidade à perda de óleo dos oleogéis de RBW, este agente estruturante apresenta ria maior potencial de aplicação, porém o oleogel CBW6 obteve alta capacidade de retenção de óleo (99,3%) e quando aplicado na formulação de cream cheese (CCBW6) apresentou resultados de firmeza e espalhabilidade mais próximos da amostra de referência, feita com gordura do leite (CMF)


Given the growing demands of regulatory agencies around the world regarding the reduction/elimination of trans fatty acids in processed foods, as well as consumer awareness about the relationship between food and health, the development of healthier alternatives to partially hydrogenated oils and others lipid sources with a high degree of saturation are necessary. Oleogel, a system composed of an oil trapped in a three-dimensional network formed by a structuring agent, presents itself as a promising solution. Among the various structuring agents, vegetable waxes stand out for their excellent oil gelling capacity. However, they have a sensory disadvantage, as they can give waxy and unpleasant aftertaste to foods. Aiming at enabling the use of waxes as structuring agents in oleogels in view of their excellent technological performance, this study proposes the evaluation and application of oleogels based on soybean oil (SBO) structured with rice bran wax (RBW) at 2 and 4% (m/m) or carnauba (CBW) at 3 and 6% (m/m). The raw materials were characterized and the gelling behavior of each wax was evaluated by analysis of texture by cone penetration, stability to oil loss by centrifugation, cohesive energy by Hansen solubility parameter (HSP) and crystallization and melting behavior. by differential scanning calorimetry (DSC). The results showed that both waxes are able to form structurally stable oleogels, however, oleogel with 2% RBW showed greater firmness at 20 °C (190.4 gf/cm2) than oleogel with 6% CBW at 5° C (186.1 gf/cm2). At the end of 5 days, the oil retention capacity of oleogel prepared with RBW was 100% at concentrations of 2 and 4% (m/m), against 61 and 99.3% of oleogel prepared with CBW at concentrations of 3 and 6% (m/m), respectively. These results can be explained by the difference between the cohesive energies, that is, the degree of molecular interaction between the solvent and the solute of each oleogel. According to the distance results, which predicts if the formed gel will be strong, weak or if there will be no gel formation, the CBW solute showed less interaction with the oil (3.3 MPa1/2) than the RBW solute (3 ,7 MPa1/2). Oleogels were applied as ingredients in different cream cheese formulations, which were analyzed for different texture parameters and these results were compared to a commercial reference. None of the samples produced had texture results statistically equal to those of commercial cream cheese (CC), which can be explained by the differences in formulation and processing of the products. Given the results for texture and oil binding capacity of RBW oleogels, this structuring agent would present greater application potential, but CBW6 oleogel obtained high oil biding capacity (99.3%) and when applied in cream cheese formulation (CCBW6) showed firmness and spreadability results closer to the reference sample, made with milk fat (CMF)


Subject(s)
Chemistry, Pharmaceutical , Industrialized Foods , Food/adverse effects , Vegetables , Waxes/pharmacology , Soybean Oil/classification , Calorimetry/methods , Calorimetry, Differential Scanning/methods
2.
J. oral res. (Impresa) ; 7(9): 426-431, ene. 2, 2018. ilus, tab
Article in English | LILACS | ID: biblio-1121162

ABSTRACT

Introduction: Ostene is a new synthetic bone hemostatic wax-like inert and biocompatible material that dissolves within two days after application. bone wax is a well- known topical hemostatic agent, easy to use, and its application is very simple. wound healing is a complex biological process; bone is a dynamic tissue that is continuously resorbed, renewed, and remodeled. materials and methods: twenty domestic rabbits were divided into four groups (day 1, day 3, day 7, and day 14). each rabbit was anaesthetized and three holes were drilled in the mandible: one was filled with Ostene, another with bone wax, and the other was left unfilled as control. sites of intervention were assessed by histopathology. results and Discussion: Ostene and bone wax showed osteoinductive property in bone healing with no inflammatory reaction. our study revealed new bone formation within 14 days in Ostene group. after histopathological analysis and scoring was finished, analysis by SPSS 14 software showed a significant difference between the use of Ostene and bone wax. conclusion: Ostene showed superiority over bone wax in bone healing, and it can be used in the same way as bone wax with no interference with bone healing and osteogenesis. Ostene has no side effects following application.


Subject(s)
Animals , Rabbits , Waxes/pharmacology , Wound Healing/drug effects , Hemostatics/administration & dosage , Hemostatics/pharmacology , Osteogenesis , Cancellous Bone
3.
Acta cir. bras ; 26(4): 274-278, July-Aug. 2011. ilus
Article in English | LILACS | ID: lil-594346

ABSTRACT

PURPOSE: To quantify the amount of bone formation in the calvarial region of Wistar rats after craniotomy using bone wax as a haemostatic agent. METHODS: Surgery to produce bilateral, symmetric, full-thickness cranial defects (area: 18 mm²) was performed in eight animals. The right side of the cranium remained open and the edges of the left side osseous defect was covered with bone wax. Calvaria were imaged immediately after surgery and 12 weeks postoperatively by computerized tomography. The areas of the bone defects were measured in three-dimensional images using Magics 13.0 (Materialise-Belgic, software CAD). RESULTS: The average amount of bone formation on the left and right side respectively was 4.85 mm² and 8.16 mm². Statistically significant differences between the amount of bone formation on the left and right sides were seen. CONCLUSIONS: Bone wax significantly diminishes the rate of bone formation in calvarial defects in a rat model.


OBJETIVO: Quantificar a formação óssea da região da calvaria de ratos Wistar submetidos à craniotomia com a utilização de cera de osso como agente hemostático. MÉTODOS: Cirurgia para realizar um defeito ósseo craniano bilateral, simétrico (área: 18 mm²) e com espessura total foi realizado em oito animais. O lado direito do crânio permaneceu aberto e as extremidades do defeito ósseo do lado esquerdo foram recobertas com cera de osso. O crânio foi submetido à avaliação radiológica imediatamente após a cirurgia e 12 semanas após a cirurgia com a utilização de tomografia computadorizada. As áreas dos defeitos ósseos foram medidas através de imagens tridimensionais e utilizando o programa de computador Magics 13.0 (Materialise-Belgic, software CAD). RESULTADOS: A quantidade média de formação óssea no lado esquerdo e direito foi respectivamente de 4.85 mm² e 8.16 mm². Diferença estatisticamente significante foi observada entre o lado direito e esquerdo. CONCLUSÕES: A cera de osso diminuiu significativamente a formação óssea nos defeitos ósseos em modelo animal.


Subject(s)
Animals , Male , Rats , Hemostatics/pharmacology , Osteogenesis/drug effects , Palmitates/pharmacology , Skull/surgery , Waxes/pharmacology , Wound Healing/drug effects , Cephalometry , Disease Models, Animal , Inflammation/pathology , Osteogenesis/physiology , Photomicrography , Rats, Wistar , Skull/injuries , Skull , Time Factors , Tomography, X-Ray Computed , Wound Healing/physiology
4.
Mem. Inst. Oswaldo Cruz ; 102(6): 681-685, Sept. 2007. ilus, tab
Article in English | LILACS | ID: lil-463472

ABSTRACT

Antibacterial and antifungal properties of wax and hexane extracts of Citrus spp. peels were tested using bioautographic and microdilution techniques against three plant pathogenic fungi (Penicillium digitatum, Curvularia sp., and Colletotrichum sp.), two human pathogens (Trichophyton mentagrophytes and Microsporum canis), and two opportunistic bacteria (Escherichia coli and Staphylococcus aureus). Two polymethoxylated flavonoids and a coumarin derivative, were isolated and identified from peel extracts, which presented antimicrobial activity especially against M. canis and T. mentagrophytes: 4',5,6,7,8-pentamethoxyflavone (tangeritin) and 3',4',5,6,7,8-hexamethoxyflavone (nobiletin) from C. reticulata; and 6,7-dimethoxycoumarin (also known as escoparone, scoparone or scoparin) from C. limon.


Subject(s)
Anti-Bacterial Agents/pharmacology , Citrus/chemistry , Escherichia coli/drug effects , Hexanes/pharmacology , Mitosporic Fungi/drug effects , Staphylococcus aureus/drug effects , Waxes/pharmacology , Hexanes/chemistry , Hexanes/isolation & purification , Microbial Sensitivity Tests , Plant Extracts/pharmacology , Waxes/chemistry , Waxes/isolation & purification
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