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1.
Environ Pollut ; 364(Pt 1): 125205, 2025 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-39542166

RESUMO

Trifluralin, Chlorpyrifos, and Procymidone migration performance from polyethylene (PE) and biodegradable (Mater-Bi: M-B) mulching films was examined. Desorption of pesticides from PE and M-B was studied using soil-plastic microcosms, considering temperature, soil humidity, and mulching film type as experimental variables. Trifluralin and Chlorpyrifos desorption was higher for PE than for M-B under all experimental conditions. In both cases, as the temperature increased from 25 °C to 40 °C, pesticide migration also increased, whereas as the soil humidity raised from 30% to 60%, pesticide desorption decreased. In the case of Procymidone, migration from PE and M-B at 25 °C was similar under both soil moisture conditions. Migration percentages were similar for both mulch films at 40 °C and 30% soil humidity. However, at higher soil moisture (60%), migration from M-B was greater than from PE. A linear relationship was observed between the percentage of migration and the vapor pressure of the pesticides. In all cases, migration increased with higher vapor pressure, indicating a possible migration mechanism in the vapor phase. Pesticide migration increased at high temperatures (40 °C). The effect of soil humidity in reducing pesticide migration was more significant at lower levels (30%). In addition, the mesoplastic sorption of pesticides in soil columns was studied using PE and M-B films. While the recoveries for Trifluralin, Chlorpyrifos, and Procymidone in the PE films were 0.05% ± 0.01%, 0.13% ± 0.03%, and non-detectable, the recoveries for M-B were: 0.49% ± 0.07%, 0.31% ± 0.09%, and 0.17% ± 0.10%, respectively, indicating that M-B was a better adsorbent than PE in all cases. This behavior should be considered in combination with the lower migration percentages observed for this type of mulching film in the microcosm experiments. These results could indicate a potential carrier effect of pesticide on biomesoplastic in the environment.


Assuntos
Clorpirifos , Praguicidas , Polietileno , Poluentes do Solo , Praguicidas/química , Polietileno/química , Poluentes do Solo/química , Clorpirifos/química , Adsorção , Solo/química , Trifluralina/química , Plásticos Biodegradáveis/química , Temperatura , Compostos Bicíclicos com Pontes
2.
Arch Microbiol ; 206(12): 457, 2024 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-39499332

RESUMO

Plastics offer versatility, durability and low production costs, but they also pose environmental and health risks due to improper disposal, accumulation in water bodies, low recycling rates and temporal action that causes physicochemical changes in plastics and the release of toxic products to animal health and nature. Some microorganisms may play crucial roles in improving plastic waste management in the future. Cunningamella echinulata has been identified as a promising candidate that remains viable for long periods and produces a cutinase that is capable of degrading plastic. Other recent approaches involving the use of microorganisms are discussed in this review. However, there does not seem to be a single science that is efficient or most appropriate for solving the problem of plastic pollution on the planet at present. Regulations, especially the implementation of different laws that address the entire plastic cycle in different countries, such as Brazil, the USA, China and the European Union, play important roles in the management of this waste and can contribute to reducing this problem. In the context of the transversality of the information compiled here, the current limitations are discussed, and an effective plan is proposed to reduce plastic pollution. Although it is challenging, it involves implementing legislation, promoting sustainable alternatives, improving collection and recycling systems, encouraging reuse, supporting research and technological innovation, promoting corporate responsibility, collaborating globally, raising public awareness, optimizing waste management and, above all, continuously monitoring the progress of actions based on measurable metrics.


Assuntos
Biodegradação Ambiental , Plásticos , Reciclagem , Gerenciamento de Resíduos , Plásticos/metabolismo , Gerenciamento de Resíduos/métodos , Política Ambiental/legislação & jurisprudência , Brasil , Hidrolases de Éster Carboxílico/metabolismo , Plásticos Biodegradáveis/metabolismo , Poluição Ambiental/prevenção & controle , Bactérias/metabolismo
3.
Sci Total Environ ; 955: 176763, 2024 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-39393684

RESUMO

Evaluating compostability is increasingly essential for proving commercial bio-based cutlery or packaging since these materials must biodegrade under controlled conditions quickly. Utensils for eating represent Mexico's most popular consumer single-use materials, and Mexican regulations based on biodegradation or compostability are still vague and lack scientific evaluations. This study analyzed three bio-based polymeric materials (bags, dishes, and forks) from commercial brands following Mexican regulations and using various analytical techniques to verify their biodegradability and compostability. First, weight loss measurements, stress-strain tests, and topographic imaging were applied for preliminary observations at the macro scale up to 90 days of compostability. Besides, spectroscopy, microscopy, and thermal techniques indicate changes and behavior of the bio-based materials depending on the composition. The results suggest that bags exhibited the highest decomposition rate (80 %) compared to dishes and forks. Similarly, mechanical resistance indicates a reduction of 62 % for bags, 30 % for dishes, and almost none for forks. Texture image analysis revealed that the complexity and roughness of the materials increased over time, correlating with the physical changes observed. These results indicate minimal surface topography changes and higher stiffness for dishes and forks, indicating low biodegradability. SEM images supported these findings, showing surface degradation in bags and dishes but not in forks. FTIR and XRD analyses confirmed the presence of polyamide (bags) and polypropylene (dishes and forks). These results reduce biodegradation and differ from the claims made by manufacturers. The thermal analysis found similar results, indicating that the materials' thermal stability decreased after degradation, which is related to lower biodegradability and compostability. Overall, the study concluded only bags meet the criteria for compostability in national regulations. However, dishes and forks made of petroleum-derived polymers have higher resistance to natural and microbial degradation.


Assuntos
Plásticos Biodegradáveis , Biodegradação Ambiental , Compostagem , México , Plásticos
4.
Sci Total Environ ; 949: 174876, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39067601

RESUMO

Plastics derived from fossil fuels are used ubiquitously owing to their exceptional physicochemical characteristics. However, the extensive and short-term use of plastics has caused environmental challenges. The biotechnological plastic conversion can help address the challenges related to plastic pollution, offering sustainable alternatives that can operate using bioeconomic concepts and promote socioeconomic benefits. In this context, using soil from a plastic-contaminated landfill, two consortia were established (ConsPlastic-A and -B) displaying versatility in developing and consuming polyethylene or polyethylene terephthalate as the carbon source of nutrition. The ConsPlastic-A and -B metagenomic sequencing, taxonomic profiling, and the reconstruction of 79 draft bacterial genomes significantly expanded the knowledge of plastic-degrading microorganisms and enzymes, disclosing novel taxonomic groups associated with polymer degradation. The microbial consortium was utilized to obtain a novel Pseudomonas putida strain (BR4), presenting a striking metabolic arsenal for aromatic compound degradation and assimilation, confirmed by genomic analyses. The BR4 displays the inherent capacity to degrade polyethylene terephthalate (PET) and produce polyhydroxybutyrate (PHB) containing hydroxyvalerate (HV) units that contribute to enhanced copolymer properties, such as increased flexibility and resistance to breakage, compared with pure PHB. Therefore, BR4 is a promising strain for developing a bioconsolidated plastic depolymerization and upcycling process. Collectively, our study provides insights that may extend beyond the artificial ecosystems established during our experiments and supports future strategies for effectively decomposing and valorizing plastic waste. Furthermore, the functional genomic analysis described herein serves as a valuable guide for elucidating the genetic potential of microbial communities and microorganisms in plastic deconstruction and upcycling.


Assuntos
Biodegradação Ambiental , Microbiota , Plásticos , Plásticos/metabolismo , Microbiologia do Solo , Polietilenotereftalatos/metabolismo , Poluentes do Solo/metabolismo , Polímeros/metabolismo , Bactérias/metabolismo , Bactérias/genética , Plásticos Biodegradáveis/metabolismo , Consórcios Microbianos , Pseudomonas putida/metabolismo , Pseudomonas putida/genética
5.
Sci Total Environ ; 944: 173735, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-38857803

RESUMO

Environmental concerns about microplastics (MPs) have motivated research of their sources, occurrence, and fate in aquatic and soil ecosystems. To mitigate the environmental impact of MPs, biodegradable plastics are designed to naturally decompose, thus reducing the amount of environmental plastic contamination. However, the environmental fate of biodegradable plastics and the products of their incomplete biodegradation, especially micro-biodegradable plastics (MBPs), remains largely unexplored. This comprehensive review aims to assess the risks of unintended consequences associated with the introduction of biodegradable plastics into the environment, namely, whether the incomplete mineralization of biodegradable plastics could enhance the risk of MBPs formation and thus, exacerbate the problem of their environmental dispersion, representing a potentially additional environmental hazard due to their presumed ecotoxicity. Initial evidence points towards the potential for incomplete mineralization of biodegradable plastics under both controlled and uncontrolled conditions. Rapid degradation of PLA in thermophilic industrial composting contrasts with the degradation below 50 % of other biodegradables, suggesting MBPs released into the environment through compost. Moreover, degradation rates of <60 % in anaerobic digestion for polymers other than PLA and PHAs suggest a heightened risk of MBPs in digestate, risking their spread into soil and water. This could increase MBPs and adsorbed pollutants' mobilization. The exact behavior and impacts of additive leachates from faster-degrading plastics remain largely unknown. Thus, assessing the environmental fate and impacts of MBPs-laden by-products like compost or digestate is crucial. Moreover, the ecotoxicological consequences of shifting from conventional plastics to biodegradable ones are highly uncertain, as there is insufficient evidence to claim that MBPs have a milder effect on ecosystem health. Indeed, literature shows that the impact may be worse depending on the exposed species, polymer type, and the ecosystem complexity.


Assuntos
Plásticos Biodegradáveis , Biodegradação Ambiental , Microplásticos , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Poluentes do Solo/análise , Plásticos
6.
J Mol Graph Model ; 126: 108674, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37984192

RESUMO

Petroleum-based plastics dominate everyday life, necessitating the exploration of natural polymers as alternatives. Starch, abundant and biodegradable, is a promising raw material. However, understanding the molecular mechanisms underlying starch plasticization has proven challenging. To address this, we employ molecular dynamics simulations, focusing on amylose as a model. Our comprehensive evaluation revealed that chain size affects solubility, temperature influenced diffusivity and elastic properties, and oleic acid expressed potential as an alternative plasticizer. Furthermore, blending glycerol or oleic acid with water suggested the enhancement amylose's elasticity. These findings contribute to the design of sustainable and improved biodegradable plastics.


Assuntos
Plásticos Biodegradáveis , Amido , Amilose , Ácido Oleico , Glicerol , Simulação de Dinâmica Molecular , Plásticos
7.
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
8.
J Environ Manage ; 322: 116074, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36049309

RESUMO

Among global efforts facing plastic pollution, their gradual replacement with alternative materials has gained strength during the last decade. We identified five stakeholders and their respective key participation in the chain of bio-based, biodegradable and compostable plastics (BBCP), which have contributed to several flaws on governance of these materials. The widespread unfamiliarity of the consumers about biodegradability concepts has been leading to misguided purchase decisions and disposal practices, along with possible littering behavior. Simultaneously, the adoption of greenwashing practices by stores and manufacturers contribute to disseminating misguided decisions on plastic consumption. Such issues are further aggravated by the lack of certification standards concerning the impact of littering, including the assessment of persistency and toxicity, also covering those made with biodegradable plastics.". Moreover, even though such alternative polymers were originally conceived as a strategy to minimize plastics pollution, the almost inexistence of specific regulatory frameworks in different political scales may convert them in a relevant part of the problem. Therefore, the governance systems and management strategies need to incorporate BBCP as potentially hazardous waste as they do for conventional plastics.


Assuntos
Plásticos Biodegradáveis , Biodegradação Ambiental , Resíduos Perigosos , Plásticos , Polímeros
9.
Biomed Pharmacother ; 145: 112464, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34864313

RESUMO

IR780 is a near-infrared fluorescent dye, which can be applied as a photosensitizer in photodynamic (PDT) and photothermal (PTT) therapies and as a biodistribution tracer in imaging techniques. We investigated the growth and migration inhibition and mechanism of death of breast tumor cells, MCF-7 and MDA-MB-231, exposed to polymeric nanocapsules (NC) comprising IR780 covalently linked to the biodegradable polymer PLA (IR-PLA) and IR780 physically encapsulated (IR780-NC) in vitro. Both types of NC had mean diameters around 120 nm and zeta potentials around -40 mV. IR-PLA-NC was less cytotoxic than IR780 NC to a non-tumorigenic mammary epithelial cell line, MCF-10A, which is an important aspect of selectivity. Free-IR780 was more cytotoxic than IR-PLA-NC for MCF-7 and MDA-MB-231 cells after illumination with a 808 nm laser. IR-PLA NC was effective to inhibit colony formation (50%) and migration (30-40%) for both cancer cell lines. MDA-MB-231 cells were less sensitive to all IR780 formulations compared to MCF-7 cells. Cell uptake was higher with IR-PLA-NC than with IR780-NC and free-IR780 in both cancer cell lines (p < 0.05). NC uptake was higher in MCF-7 than in MDA-MB-231 cells. IR-PLA-NC induced a higher percentage of apoptosis upon illumination in MDA-MB-231 than in MCF-7 cells. The necrosis mechanism of death predominated in treatments with free-IR780 and with encapsulated IR780 NC, suggestive of damages at the plasma membrane. IR780 conjugated with PLA increased the apoptotic pathway and demonstrated potential as a multifunctional theranostic agent for breast cancer treatment with increased cellular uptake, photodynamic activity and more reliable tracking in cell-image studies.


Assuntos
Neoplasias da Mama , Indóis/farmacologia , Nanocápsulas/química , Fotoquimioterapia/métodos , Polietilenoglicóis/farmacologia , Apoptose/efeitos dos fármacos , Plásticos Biodegradáveis/farmacologia , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Corantes Fluorescentes/farmacologia , Humanos , Células MCF-7 , Fármacos Fotossensibilizantes/farmacologia , Medicina de Precisão/métodos , Distribuição Tecidual
10.
Cienc. tecnol. salud ; 9(2): 189-198, 2022. il 27
Artigo em Espanhol | LILACS, DIGIUSAC, LIGCSA | ID: biblio-1415975

RESUMO

La contaminación por plásticos petroquímicos es una grave amenaza para el medio ambiente que requiere im-plementar alternativas como los bioplásticos para lograr un desarrollo sostenible. Los polihidroxialcanoatos (PHA) son polímeros utilizados para la producción de plásticos biodegradables y que han llamado la atención como sustitutos de los plásticos de base fósil. Sin embargo, el costo de producción de los PHA constituye una barrera para su producción industrial a gran escala. Las de bacterias de hábitats salinos son microorganismos prometedores para la síntesis de PHA debido a sus características tales como altos requisitos de salinidad que previenen la contaminación microbiana, la alta presión osmótica intracelular que permite una fácil lisis celular para purificar los PHA y la capacidad para usar un amplio espectro de sustratos. La presente investigación planteó determinar las cepas nativas de bacterias halófilas y halotolerantes de la Laguna de Ayarza capaces de producir PHA, establecer la capacidad que tienen de utilizar residuos agrícolas para la producción de PHA y determinar su eficiencia. Esto se logró a través de la inoculación de las cepas productoras de PHA en medios de fermentación con pulpa de café, cáscaras de plátanos y salvado de trigo lo que permitió determinar las cepas más eficientes. Se encontró que las bacterias productoras de PHA pertenecen a las especies: Alcaligenes faecalis, Bacillus idriensis, Bacillus megaterium, Exiguobacterium acetylicum, E. aurantiacum, Pseudomonas cuatrocienegasensis y Sta-phylococcus capitis y que las cepas AP21-14, AP21-10 y AP21-03 mostraron los mejores resultados que podrían ser prometedores para la producción a nivel industrial.


Pollution by petrochemical plastics is a serious threat to the environment that requires the implementation of al-ternatives such as bioplastics to achieve sustainable development. Polyhydroxyalkanoates (PHAs) are polymers used for the production of biodegradable plastics and have drawn attention as substitutes for fossil-based plastics. However, the cost of producing PHAs constitutes a barrier to their large-scale industrial production. Bacteria from saline environments bacteria are promising microorganisms for PHA synthesis due to their characteristics such as high salinity requirements that prevent microbial contamination, high intracellular osmotic pressure that allows easy cell lysis to purify PHAs, and the ability to use a broad spectrum of substrates. This research project aimed to determine the native strains of halophilic and halotolerant bacteria from Laguna de Ayarza capable of producing PHA, establish their ability to use agricultural residues for the production of PHA, and determine their efficiency. This was achieved through the inoculation of the PHA-producing strains in fermentation media with coffee pulp, banana peels and wheat bran, which allowed determining the most efficient strains. It was found that the PHA-producing bacteria belong to the species: Alcaligenes faecalis, Bacillus idriensis, Bacillus mega-terium, Exiguobacterium acetylicum, E. aurantiacum, Pseudomonas cuatrocienegasensis and Staphylococcus capitis and that the strains AP21-14, AP21-10 and AP21-03 showed the best results that could be promising for production at an industrial level.


Assuntos
Humanos , Halomonas , Poli-Hidroxialcanoatos/análise , Plásticos Biodegradáveis/química , Pseudomonas/química , Bacillus megaterium/química , Laguna Costeira , Alcaligenes faecalis/química , Fermentação , Staphylococcus capitis , Exiguobacterium/química , Guatemala , Resíduos Industriais/efeitos adversos
11.
Int J Mol Sci ; 22(19)2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34638967

RESUMO

The objective of this work was to develop a chitosan/agar-agar bioplastic film incorporated with bacteriocin that presents active potential when used as food packaging. The formulation of the film solution was determined from an experimental design, through the optimization using the desirability function. After establishing the concentrations of the biopolymers and the plasticizer, the purified bacteriocin extract of Lactobacillus sakei was added, which acts as an antibacterial agent. The films were characterized through physical, chemical, mechanical, barrier, and microbiological analyses. The mechanical properties and water vapor permeability were not altered by the addition of the extract. The swelling property decreased with the addition of the extract and the solubility increased, however, the film remained intact when in contact with the food, thus allowing an efficient barrier. Visible light protection was improved by increased opacity and antibacterial capacity was effective. When used as Minas Frescal cream cheese packaging, it contributed to the increase of microbiological stability, showing a reduction of 2.62 log UFC/g, contributing a gradual release of the active compound into the food during the storage time. The film had an active capacity that could be used as a barrier to the food, allowing it to be safely packaged.


Assuntos
Antibacterianos/química , Bacteriocinas/química , Plásticos Biodegradáveis/química , Biopolímeros/química , Embalagem de Alimentos/métodos , Ágar/química , Materiais Biocompatíveis/química , Queijo/microbiologia , Quitosana/química , Temperatura Alta , Latilactobacillus sakei/química , Latilactobacillus sakei/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Permeabilidade , Extratos Vegetais/química , Plastificantes/química , Rodófitas/química , Solubilidade , Vapor
12.
J Hazard Mater ; 416: 125957, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492874

RESUMO

While the use of biodegradable polymers is recognized as a global strategy to minimize plastic pollution, the technical standards (TS) used to attest their biodegradability may not be in compliance with most environmental parameters observed aquatic ecosystems. Indeed, through a careful assessment of the TS currently in use, this study evidenced that these guidelines cover only a fraction of the biogeochemical parameters seen in nature and largely disregard those that occur in the deep-sea. Thus, these TS may not be able to ensure the degradation of such polymers in natural environments, where microbial activity, pH, temperature, salinity, UV radiation and pressure are highly variable. This raises environmental concern, since relevant parcel of plastic ends up in the oceans reaching deep zones. Therefore, there is an urgent need to revise these TS, which must consider the actual fate of most plastic debris and include assessments under the challenging conditions found at these types of environment, alongside microplastic formation and ecotoxicology effects. Moreover, the next generation of biodegradability tests must be designed to enable a cost-effective implementation and incorporate accurate analytical techniques to assess polymer transformation. Furthermore, certification should provide information on time scale and degradation rates and, preferably, be globally harmonized.


Assuntos
Plásticos Biodegradáveis , Poluentes Químicos da Água , Ecossistema , Ecotoxicologia , Monitoramento Ambiental , Poluição Ambiental , Oceanos e Mares , Plásticos , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
13.
Int J Biol Macromol ; 188: 628-638, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34389394

RESUMO

Thermoplastic starch (TPS) films filled with chitosan nanocapsules (CN) containing essential oils (EO) were prepared aiming active packaging. Two different EOs were studied: Ho wood (H) and Cinnamon (C). Besides, different capsules concentrations were investigated (1, 3, and 5 wt%), and the films were evaluated by chemical structure, thermal stability, crystallinity, water vapor permeability, antimicrobial assays, and potential application for strawberry packaging. The TPS/CN-Ho wood films showed a strong interaction between chitosan-starch, mainly for 3 and 5 wt%, confirmed by XRD. The FT-Raman spectra of TPS/CN-Cinnamon film indicated that Cinnamon EO quickly migrated to starch films, probably due to the new crystal structure, named C-type, affecting the film's water permeability. The addition of 1 and 3 wt% CN loaded with Ho wood or Cinnamon EO to the films decreased the water permeability. 3 wt% CN was the optimum concentration to inhibit the Escherichia coli or Bacillus subtillis growth on the films, confirming their biological activity. The films' preservation properties were evaluated using strawberries, and films with 1 or 3 wt% loaded-CN could extend the strawberries' shelf life without fungi contamination. The developed TPS films can be used as active food packaging or other films for biomedical or pharmaceutical applications.


Assuntos
Plásticos Biodegradáveis/farmacologia , Quitosana/química , Armazenamento de Alimentos , Nanocápsulas/química , Plásticos Biodegradáveis/química , Quitosana/síntese química , Cinnamomum zeylanicum/química , Escherichia coli/efeitos dos fármacos , Frutas/normas , Testes de Sensibilidade Microbiana , Óleos Voláteis/síntese química , Óleos Voláteis/química , Amido/química
14.
Food Funct ; 12(14): 6549-6557, 2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34096962

RESUMO

The purpose of this study was to encapsulate carvacrol into liposomes in order to promote its application in active food packaging. Response surface methodology was used to evaluate the effect of the concentration of the liposomal components on its characteristics. The optimum formulation for the preparation of liposomes with the highest encapsulation efficiency (59.0 ± 1.99%) was found to be 3000 µg mL-1 of cholesterol and 4000 µg mL-1 of carvacrol. Carvacrol reduced the polydispersity index and increased the zeta potential and the thermal stability of liposomes. Fourier-transform infrared spectroscopy indicated that the interaction of carvacrol with liposomes occurred probably through hydrogen-bonding. The incorporation into liposomes maintained the antibacterial effect of carvacrol, but when in the film, carvacrol liposomes were not effective against the microorganisms tested. Liposomes may offer a viable option for stabilizing carvacrol, however, more studies are necessary to enable its application in food packaging.


Assuntos
Antibacterianos/química , Cimenos/química , Embalagem de Alimentos/métodos , Lipossomos/química , Álcool de Polivinil/química , Antibacterianos/farmacologia , Plásticos Biodegradáveis/química , Cimenos/farmacologia , Escherichia coli/efeitos dos fármacos , Lipossomos/farmacologia , Testes de Sensibilidade Microbiana/métodos , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Staphylococcus aureus/efeitos dos fármacos
15.
Carbohydr Polym ; 251: 117009, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33142575

RESUMO

Starch is an excellent alternative to produce packaging materials, however, due to its high hydrophilicity, it is necessary to mix it with other polymers. Chitosan (CTS) is a polymer extracted from shrimp shells and crabs, which can be used to make biodegradable materials. The principal component of biodegradable was corn starch and chitosan, the copolymer pluronic F127 was incorporated in several concentrations and its effect on the water vapor barrier, morphological, thermal, and mechanical properties of the films was evaluated, because its incorporation in the formulation of biodegradable materials could increase its hydrophobicity. The surface of starch-chitosan composite films obtained was more homogeneous and smoother with the increase in the content of pluronic F127. The %S and WVP of the starch-chitosan films decreased from 42 to 3%, and 21 × 10-11 to 3 × 10-14 g. m-1s-1 Pa-1, respectively, with the incorporation of pluronic from 3%, which makes these materials a good alternative for product packaging.


Assuntos
Plásticos Biodegradáveis/química , Quitosana/química , Embalagem de Alimentos , Poloxâmero/química , Amido/química , Interações Hidrofóbicas e Hidrofílicas , Permeabilidade , Solubilidade , Vapor , Resistência à Tração , Água/química
16.
J Interv Cardiol ; 2020: 6340716, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33380923

RESUMO

AIMS: The goal of this study was to evaluate the performance of the InspironTM coronary stent (Scitech Medical™, Goiás, Brazil). The InspironTM sirolimus-eluting stent uses an ultrathin L-605 cobalt-chromium alloy with a 75 µm strut thickness platform coated with an abluminal biodegradable polymer. The polymer is eliminated from the body through the tricarboxylic acid cycle in 6-9 months, releasing 80% of the drug within 30 days after its deployment. METHODS: It was a prospective, single-center registry. To represent clinical practice, all patients undergoing percutaneous coronary intervention were included in this registry. There were no exclusion criteria. Clinical follow-ups were performed at twelve months. The endpoints were the occurrence of all-cause death, definite stent thrombosis, and new revascularization. RESULTS: Between November 2017 and May 2019, 790 patients were included (1067 lesions). The mean age was 60.42 ± 14.94 years, and 74.7% presented with acute coronary syndrome. Diabetes mellitus was present in 43.9% of patients, and previous myocardial infarction and previous percutaneous coronary intervention were present in 17.9% and 11.3%, respectively. Angiographic success was achieved in 99.1%. The incidence of all-cause death was 11.5% (6.2% in-hospital and 5.3% in the follow-up) and definitive stent thrombosis was 0.2%. New revascularization was performed in only 5.8% (target lesion revascularization: 2.2%; progression of disease in another lesion: 3.6%). Based on the multivariate regression analysis, only chronic renal failure was an independent predictor of adverse events (OR: 3.3; 95% CI: 1.22-8.92). CONCLUSION: The result of this single-center registry demonstrates the safety and excellent performance of the InspironTM stent in daily clinical practice with a low rate of adverse cardiac events.


Assuntos
Síndrome Coronariana Aguda , Plásticos Biodegradáveis/farmacologia , Ligas de Cromo/farmacologia , Stents Farmacológicos/efeitos adversos , Intervenção Coronária Percutânea , Sirolimo/farmacologia , Síndrome Coronariana Aguda/mortalidade , Síndrome Coronariana Aguda/cirurgia , Brasil/epidemiologia , Materiais Revestidos Biocompatíveis/farmacologia , Reestenose Coronária/epidemiologia , Reestenose Coronária/etiologia , Reestenose Coronária/cirurgia , Feminino , Humanos , Imunossupressores/farmacologia , Masculino , Pessoa de Meia-Idade , Avaliação de Processos e Resultados em Cuidados de Saúde , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/instrumentação , Intervenção Coronária Percutânea/métodos , Estudos Prospectivos , Desenho de Prótese , Sistema de Registros/estatística & dados numéricos , Reoperação/estatística & dados numéricos
17.
Int J Biol Macromol ; 165(Pt A): 1038-1046, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32987083

RESUMO

The incorporation of plant-based extracts into polymer-based coatings is an efficient alternative to increase the shelf-life of stored fruit and to decrease or even prevent bacterial growth. Considering strawberries, it is also important to preserve their high antioxidant activity. Hence, this work evaluated the efficiency of a coating based on native cassava starch (NCS), gelatin, and sorbitol, containing different concentrations of Tetradenia riparia extract, in delaying the ripening process of strawberries stored under refrigerated conditions, and in preventing bacterial growth and antioxidant activity losses. Both concentrations of extract (500 or 1000 µg mL-1) increased the thickness, opacity, and water vapor transmission rate (WVTR) of the films when compared to the film without extract, but decreased the solubility. Even though the film without extract was expected to create a more efficient barrier to the coated fruits, the films containing the extract led to similar results of soluble solids (SS), titratable acidity (TA), and vitamin C. Nevertheless, the extract incorporation improved the control over bacterial growth, and preserved the high antioxidant activity of the strawberries within ten days of storage.


Assuntos
Antioxidantes/química , Plásticos Biodegradáveis/química , Microbiologia de Alimentos , Lamiaceae/química , Embalagem de Alimentos , Conservação de Alimentos , Armazenamento de Alimentos , Fragaria , Frutas/química , Gelatina/química , Humanos , Extratos Vegetais/química , Amido/química
18.
Molecules ; 25(15)2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-32751910

RESUMO

Over the past decade, consumers have demanded natural, completely biodegradable active packaging serving as food containers. Bioactive plant compounds can be added to biopolymer-based films to improve their functionality, as they not only act as barriers against oxidation, microbiological, and physical damage, they also offer functionality to the food they contain. A water-in-oil (W/O) nanoemulsion was produced by applying ultrasound to xoconostle extract and orange oil, and was incorporated into gelatine films in different proportions 1:0 (control), 1:0.10, 1:0.25, 1:0.50, 1:0.75, and 1:1 (gelatine:nanoemulsion). The nanoemulsions had an average size of 118.80 ± 5.50 nm with a Z-potential of -69.9 ± 9.93 mV. The presence of bioactive compounds such as phenols, flavonoids, and betalains in the films was evaluated. The 1:1 treatment showed the highest presence of bioactive compounds, 41.31 ± 3.71 mg of gallic acid equivalent per 100 g (GAE)/100g for phenols, 28.03 ± 3.25 mg of quercetin equivalent per 100 g (EQ)/100g flavonoids and 0.014 mg/g betalains. Radical inhibition reached 72.13% for 2,20-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS), and 82.23% for 1,1-diphenyl-2-picrylhydrazyl (DPPH). The color of the films was influenced by the incorporation of nanoemulsions, showing that it was significantly different (p < 0.05) to the control. Mechanical properties, such as tensile strength, Young's modulus, and percentage elongation, were affected by the incorporation of nanoemulsified bioactive compounds into gelatine films. The obtained films presented changes in strength and flexibility. These characteristics could be favorable as packaging material.


Assuntos
Plásticos Biodegradáveis/química , Embalagem de Alimentos , Gelatina/química , Nanoestruturas/química , Opuntia/química , Extratos Vegetais/química , Óleos de Plantas/química , Antioxidantes/análise , Antioxidantes/química , Betalaínas/análise , Betalaínas/química , Cor , Emulsões/síntese química , Emulsões/química , Flavonoides/análise , Flavonoides/química , Gelatina/síntese química , Fenóis/análise , Fenóis/química
19.
Nat Commun ; 11(1): 3668, 2020 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-32699271

RESUMO

Restoration is becoming a vital tool to counteract coastal ecosystem degradation. Modifying transplant designs of habitat-forming organisms from dispersed to clumped can amplify coastal restoration yields as it generates self-facilitation from emergent traits, i.e. traits not expressed by individuals or small clones, but that emerge in clumped individuals or large clones. Here, we advance restoration science by mimicking key emergent traits that locally suppress physical stress using biodegradable establishment structures. Experiments across (sub)tropical and temperate seagrass and salt marsh systems demonstrate greatly enhanced yields when individuals are transplanted within structures mimicking emergent traits that suppress waves or sediment mobility. Specifically, belowground mimics of dense root mats most facilitate seagrasses via sediment stabilization, while mimics of aboveground plant structures most facilitate marsh grasses by reducing stem movement. Mimicking key emergent traits may allow upscaling of restoration in many ecosystems that depend on self-facilitation for persistence, by constraining biological material requirements and implementation costs.


Assuntos
Adaptação Fisiológica , Recuperação e Remediação Ambiental/métodos , Hydrocharitaceae/fisiologia , Áreas Alagadas , Zosteraceae/fisiologia , Plásticos Biodegradáveis , Biomimética/métodos , Ecologia/métodos , Recuperação e Remediação Ambiental/instrumentação , Florida , Países Baixos , Água do Mar , Suécia , Clima Tropical , Índias Ocidentais
20.
J Food Sci ; 85(4): 892-902, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32144764

RESUMO

In this study, the effect of chia mucilage (CM) and protein concentrate (CPC) contents on the physicochemical, thermal, mechanical, and optical characteristics of developed films was evaluated. Films were prepared dissolving CM:CPC mixtures (1% w/v) in seven ratios (0:1, 1:4, 1:2, 1:1, 2:1, 4:1, 1:0). Microstructure of treatments with higher CM revealed the formation of polysaccharide granules. A semicrystalline behavior was manifested in 1:0, which decreased as CPC content in the formulations increased. Contact angle values obtained for 1:1 and 2:1 were the highest (61.24° and 62.44°), evidencing less affinity to water than other films. TGA analysis suggest that films showed thermal stability at less than 225 °C. Melting temperatures above 85 °C were found for all films in the evaluated range (50 °C to 200 °C) of DSC analysis. Higher CM concentrations in films increased the force required to break them (13.5 MPa) and their elongation capacity (5.20%). As the CM ratio in formulations was increased, the color difference was lower (ΔE = 27.45), water vapor permeability was higher (10.9 × 10-11  g/m·s·Pa), but transparency was statistically the same for all treatments (6.62 to 7.26). After analyzing all films properties, 2:1 formulation corresponding to 25:75% w/v mixtures of CM:CPC would be the best option for use in food packaging.


Assuntos
Embalagem de Alimentos/instrumentação , Extratos Vegetais/química , Mucilagem Vegetal/química , Proteínas de Plantas/química , Salvia/química , Plásticos Biodegradáveis/química , Fenômenos Biomecânicos , Temperatura Alta , Permeabilidade , Sementes/química , Vapor/análise
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