6 research outputs found
Composition and in vitro antimicrobial activity of pink pepper fruit essential oils / Composição e atividade antimicrobiana in vitro de óleos essenciais de frutos de pimenta-rosa
The fruit of Aroeira, popularly called pink pepper, has aroused researchers interest due to the effects of the different constituents present in its essential oil. In Espírito Santo, the largest producer and exporter in the world since 2012, most pink pepper production is spontaneous and of great importance to rural producers. The aim of this work was to identify the chemical constituents and evaluate the antibacterial action of essential oils extracted from ripe pink pepper fruits (PPEO) obtained from six rural properties located in São Mateus-ES, coded as P5, P6, P7, P8, P9 and P10. Through chromatographic analysis (CG/MS), 13 compounds were detected, 10 monoterpenes and 3 sesquiterpenes, of which limonene (31.28%), delta3carene (28.71%) and alpha-pinene (15.01%) were the majority. In the agar diffusion test, the PPEO from the six farms showed inhibition against S. aureus, especially for the P6, P7, P8 and P10 oils, which did not differ significantly from the antibiotic Ampicillin used as a control. However, the essential oils tested were ineffective against E. coli. In the Minimum Inhibitory Concentration (MIC) test, the bacteria most sensitive to all oils was S. aureus, presenting the lowest values and, in contrast, P. aeruginosa showed greater resistance to their action. The PPEO that showed the greatest effect compared to the others against all bacteria was P7
Antioxidant and antimicrobial activities of the first hop (Humulus lupulus L.) cultivars produced in Brazil.
Hop (Humulus lupulus L.) is a plant that has shown great versatility as a raw material in food and pharmaceutical industries. Essential for beer production, it is associated with flavor, aroma and antioxidant and antimicrobial properties of the beverage,O lúpulo (Humulus lupulus L.) é uma planta que tem demonstrado grande versatilidade como matéria-prima em indústrias alimentícias e farmacêuticas. Imprescindível na produção da cerveja, está associado a características de sabor, aroma e propriedades antioFundação Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES
Biodegradation of Polymers: Stages, Measurement, Standards and Prospects
Nowadays, sustainable and biodegradable bioplastics are gaining significant attention due to resource depletion and plastic pollution. An increasing number of environmentally friendly plastics are being introduced to the market with the aim of addressing these concerns. However, many final products still contain additives or mix non-biodegradable polymers to ensure minimum performance, which often undermines their ecological footprint. Moreover, there is a lack of knowledge about all stages of biodegradation and their accuracy in classifying products as biodegradable. Therefore, this review provides an overview of biodegradable polymers, elucidating the steps and mechanisms of polymer biodegradation. We also caution readers about the growing marketing practice of “greenwashing” where companies or organizations adopt green marketing strategies to label products with more environmental benefits than they have. Furthermore, we present the main standards for evaluating biodegradation, tools, and tests capable of measuring the biodegradation process. Finally, we suggest strategies and perspectives involving concepts of recycling and the circularity of polymers to make them more environmentally friendly and sustainable. After all, “throwing away” plastics should not be an option because there is no outside when there is only one planet
Ionic Strength of Methylcellulose-Based Films: An Alternative for Modulating Mechanical Performance and Hydrophobicity for Potential Food Packaging Application
The growing environmental concern with the inappropriate disposal of conventional plastics has driven the development of eco-friendly food packaging. However, the intrinsic characteristics of polymers of a renewable origin, e.g., poor mechanical properties, continue to render their practical application difficult. For this, the present work studied the influence of ionic strength (IS) from 0 to 500 mM to modulate the physicochemical properties of methylcellulose (MC). Moreover, for protection against biological risks, Nisin-Z was incorporated into MC’s polymeric matrices, providing an active function. The incorporation of salts (LiCl and MgCl2) promoted an increase in the equilibrium moisture content in the polymer matrix, which in turn acted as a plasticizing agent. In this way, films with a hydrophobic surface (98°), high true strain (85%), and low stiffness (1.6 mPa) can be manufactured by addition of salts, modulating the IS to 500 mM. Furthermore, films with an IS of 500 mM, established with LiCl, catalyzed antibacterial activity against E. coli, conferring synergism and extending protection against biological hazards. Therefore, we demonstrated that the IS control of MC dispersion presents a new alternative to achieve films with the synergism of antibacterial activity against Gram-negative bacteria in addition to flexibility, elasticity, and hydrophobicity required in various applications in food packaging
Ionic Strength of Methylcellulose-Based Films: An Alternative for Modulating Mechanical Performance and Hydrophobicity for Potential Food Packaging Application
The growing environmental concern with the inappropriate disposal of conventional plastics has driven the development of eco-friendly food packaging. However, the intrinsic characteristics of polymers of a renewable origin, e.g., poor mechanical properties, continue to render their practical application difficult. For this, the present work studied the influence of ionic strength (IS) from 0 to 500 mM to modulate the physicochemical properties of methylcellulose (MC). Moreover, for protection against biological risks, Nisin-Z was incorporated into MC’s polymeric matrices, providing an active function. The incorporation of salts (LiCl and MgCl2) promoted an increase in the equilibrium moisture content in the polymer matrix, which in turn acted as a plasticizing agent. In this way, films with a hydrophobic surface (98°), high true strain (85%), and low stiffness (1.6 mPa) can be manufactured by addition of salts, modulating the IS to 500 mM. Furthermore, films with an IS of 500 mM, established with LiCl, catalyzed antibacterial activity against E. coli, conferring synergism and extending protection against biological hazards. Therefore, we demonstrated that the IS control of MC dispersion presents a new alternative to achieve films with the synergism of antibacterial activity against Gram-negative bacteria in addition to flexibility, elasticity, and hydrophobicity required in various applications in food packaging
Development and Investigation of Zein and Cellulose Acetate Polymer Blends Incorporated with Garlic Essential Oil and β-Cyclodextrin for Potential Food Packaging Application
The obtainment of new materials with distinct properties by mixing two or more polymers is a potential strategy in sustainable packaging research. In the present work, a blend of cellulose acetate (CA) and zein (60:40 wt/wt CA:zein) was manufactured by adding glycerol or tributyrin as plasticizers (30% wt/wt), and garlic essential oil (GEO), complexed (IC) or not with β-cyclodextrin (βCD), to produce active packaging. Blends plasticized with tributyrin exhibited a more homogeneous surface than those containing glycerol, which showed major defects. The blends underperformed compared with the CA films regarding mechanical properties and water vapor permeability. The presence of IC also impaired the films’ performance. However, the blends were more flexible than zein brittle films. The films added with GEO presented in vitro activity against Listeria innocua and Staphylococcus aureus. The IC addition into films, however, did not ensure antibacterial action, albeit that IC, when tested alone, showed activity against both bacteria. These findings suggest that the mixture of CA and plasticizers could increase the range of application of zein as a sustainable packaging component, while essential oils act as a natural bioactive to produce active packaging