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1.
Sensors (Basel) ; 19(10)2019 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-31108970

RESUMO

Patients with paralysis, spinal cord injury, or amputated limbs could benefit from using brain-machine interface technology for communication and neurorehabilitation. In this study, a 32-channel three-dimensional (3D) multielectrode probe array was developed for the neural interface system of a brain-machine interface to monitor neural activity. A novel microassembly technique involving lead transfer was used to prevent misalignment in the bonding plane during the orthogonal assembly of the 3D multielectrode probe array. Standard microassembly and biopackaging processes were utilized to implement the proposed lead transfer technique. The maximum profile of the integrated 3D neural device was set to 0.50 mm above the pia mater to reduce trauma to brain cells. Benchtop tests characterized the electrical impedance of the neural device. A characterization test revealed that the impedance of the 3D multielectrode probe array was on average approximately 0.55 MΩ at a frequency of 1 KHz. Moreover, in vitro cytotoxicity tests verified the biocompatibility of the device. Subsequently, 3D multielectrode probe arrays were implanted in rats and exhibited the capability to record local field potentials and spike signals.


Assuntos
Técnicas Biossensoriais , Encéfalo/fisiopatologia , Sistemas Microeletromecânicos/métodos , Neurônios/patologia , Potenciais de Ação/fisiologia , Animais , Interfaces Cérebro-Computador , Impedância Elétrica , Eletrodos Implantados , Eletroencefalografia , Humanos , Microeletrodos , Neurônios/fisiologia , Ratos , Traumatismos da Medula Espinal/diagnóstico , Traumatismos da Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/reabilitação
2.
Int J Biol Macromol ; 264(Pt 1): 130433, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38408577

RESUMO

Bacterial cellulose (BC, biocellulose) is a natural polymer of microbiological origin that meets the criteria of a biomaterial for food packaging. The aim of the research was to obtain biocellulose and test its chemical as well as physical characterization as a potential packaging for Dutch-type cheeses. Four variants of biocellulose-based material were obtained: not grinded and grinded variants obtained from YPM medium (YPM-BCNG and YPM-BCG, respectively) and not grinded and grinded variants from acid whey (AW) (AW-BCNG and AW-BCG, respectively). It was demonstrated that AW-BCNG exhibited the highest thermostability and the highest degradation temperature (348 °C). YPM-BCG and YPM-BCNG demonstrated higher sorption properties (approx. 40 %) compared to AW-BCG and AW-BCNG (approx. 15 %). Cheese packaged in biocellulose (except for YPM-BCNG) did not differ in water, fat, or protein content compared to the control cheese. All of the biocellulose packaging variants provided the cheeses with protection against unfavourable microflora. It was demonstrated that cheeses packaged in biocellulose were characterized by lower hardness, fracturability, gumminess, and chewiness than the control cheese sample. The results obtained indicate that BC may be a suitable packaging material for ripening cheeses, which shows a positive impact on selected product features.


Assuntos
Queijo , Queijo/análise , Vacina BCG , Embalagem de Alimentos/métodos , Ácidos , Proteínas do Soro do Leite , Manipulação de Alimentos/métodos
3.
Sci Total Environ ; 886: 163922, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37164094

RESUMO

Global growth impacts on the increased use and demand for natural resources, requiring solutions for the high volume of industrial waste and by-products generated from the most diverse commercial areas, mainly the food sector. Among the main residues with a large volume generated, those from fruit processing, grain cleaning in processing units, vegetables, and discards from the animal production industry stood out. Approximately 1.3 billion all food produced worldwide is lost or wasted per year being fruits, vegetables, roots, and tubers responsible for about half of the total amount. Many of these by-products have interesting nutrients in their composition such as fibers, proteins, and bioactive compounds. An interesting example is the sugarcane bagasse. Fibrous residue, derived from sugarcane extraction, the bagasse represents about 30-34 % of the total sugarcane mass. This is one of the most abundant cellulosic residues and contains approximately 39 % of cellulose, 28 % of hemicellulose, and 18 % of lignin. Therefore, as well as the bagasse, several residues from agroindustrial can be considered promising alternative substrates, being valuable sources for the development of high-value-added products, such as biopolymers, bioenergy, and chemical products. In addition, the reuse of agroindustrial wastes may be considered an attractive option for reducing the environmental impact caused by their generation. In the case of biopolymers, the energy savings of bio-based polymers is around 20-50 GJ/t of polymer. In this review, we have selected two commercially promising approaches to the application and use of agroindustrial residues, aiming their use for biodegradable packaging and microbial polysaccharides bio-production, improving overall sustainability and economic aspects of the scientific research, technology and modern industry.


Assuntos
Celulose , Saccharum , Saccharum/metabolismo , Polissacarídeos/metabolismo , Lignina/metabolismo , Biopolímeros , Polímeros
4.
Int J Biol Macromol ; 213: 1-10, 2022 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-35594940

RESUMO

Using the solution casting method, a novel biodegradable thermoplastic arrowroot (Maranta arundinacea) starch (TPAS) films containing arrowroot fiber (AF) at different concentrations (0, 2, 4, 6, 8, and 10 wt%) were developed and characterized in terms of thermal, antibacterial activity, water vapor permeability (WVP), biodegradability, and light transmittance properties. The TPAS/AF-10 biocomposite film revealed a higher degradation temperature (313.02 °C) than other biocomposite films, indicating better thermal stability. Furthermore, increasing AF concentration led to a significant (p < 0.05) reduction in the linear burning rate and WVP of the biocomposite films from 248.9 to 115.2 mm/min and 8.18 × 10-10 ×g. s-1.m-1. Pa-1 to 5.20 × 10-10 ×g. s-1.m-1. Pa-1, respectively. The addition of fibers in the surface structure had a significant impact on remarkable drop in opacity (91.1 to 74.1%). In addition, the incorporation of AF and control film showed an insignificant effect against three pathogenic bacteria, including Staphylococcus aureus (ATCC 43300), Escherichia coli (ATCC 25922), and Bacillus subtilis (B29). The soil burial findings demonstrated that the weight loss of TPAS/AF biocomposite films was significantly higher than TPAS film. Overall, the reinforcement of arrowroot fiber with TPAS film improved the properties of biocomposites for environmentally friendly food packaging applications.


Assuntos
Anti-Infecciosos , Marantaceae , Antibacterianos/química , Antibacterianos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Fibras na Dieta , Grão Comestível , Embalagem de Alimentos , Marantaceae/química , Amido/química , Vapor
5.
Int J Biol Macromol ; 194: 32-41, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34863831

RESUMO

Banana (Musa acuminata) pseudostem cellulose was extracted and acetylated (CA) to prepare membranes with potential use as bio-packages. The CA membrane was embedded by Butia seed (CA-BS) or Butia pulp (CA-BP) extracts obtained from Butia catarinenses (Butia). The produced CA, CA-BS, and CA-BP membranes were evaluated for their physical-chemical, mechanical, thermal, and antibacterial properties. The process for obtaining the cellulose yielded a material with about 92.17% cellulose (DS = 2.85). The purity, cellulose degree acetylation, and the incorporation of Butia extracts into the membranes were confirmed by FTIR. The CA-BS and CA-BP membranes showed a smaller contact angle and higher swelling ratio than the CA membrane. Furthermore, Butia seed or pulp extracts reduced the elastic modulus and deformation at break compared to the CA membrane. The DSC analysis suggested the compatibility between sections and the CA matrix, whereas the TGA analysis confirmed the thermal stability of the membranes. Moreover, less than 1% of the Butia seed and pulp extracts were put into a food simulant media from the membrane. Finally, the CA-BS and CA-BP membranes could inhibit the growth of Staphylococcus aureus and Escherichia coli on their surface, confirming the potential use of these membranes as bio-packaging for food preservation.


Assuntos
Celulose/análogos & derivados , Musa/química , Extratos Vegetais/química , Caules de Planta/química , Antibacterianos/química , Antibacterianos/farmacologia , Celulose/química , Fenômenos Químicos , Fenômenos Mecânicos , Membranas Artificiais , Embalagem de Produtos , Análise Espectral
6.
Food Chem ; 371: 131134, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34656920

RESUMO

Widespread use of traditional packaging constitutes a serious ecological problem leading to a shift to biodegradable and compostable materials. The aim of this work is to study the ability of a new biopackaging (BP), based on biodegradable and compostable material, to preserve the quality of organic chicken meat for 14 days in comparison with a polyethylene terephthalate (PET) material. Results showed that the indices of Biogenic Amines (BAs) and the 18 monitored Volatile Organic Compounds (VOCs) have a similar trend in both packaged meats. For example, the total BAs concentration in meat increased from 390 to 961 mg Kg-1 in BP and from 393 to 800 mg Kg-1 in PET, as well as the microbiological counts. The new biopackaging (BP) showed similar properties of non-biodegradable material (PET) to preserve the shelf life of organic chicken meat and it could be used instead of plastic materials to promote a circular economy.


Assuntos
Embalagem de Alimentos , Conservação de Alimentos , Animais , Galinhas , Microbiologia de Alimentos , Carne/análise
7.
Polymers (Basel) ; 14(16)2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-36015489

RESUMO

Petrochemical plastic wastes generate serious environmental problems because they are resistant to natural decomposition. The aim of this study was to develop a biodegradable active thermoplastic film composed of polyvinyl alcohol (PVA), corn starch (ST), glycerol, and the active compounds from watermelon rind extract (WMRE), or PVA/ST/WMRE, using the casting technique. The film was examined for its mechanical, antioxidant, and functional properties against selected foodborne pathogens. The results showed that the addition of 10% v/v of watermelon rind extract to the film formulation significantly increased the tensile strength from 19.44 ± 0.84 MPa to 33.67 ± 4.38 MPa and slightly increased the percent elongation at break (% EAB) from 35.04 ± 0.96% to 35.16 ± 1.08%. The antioxidant property of PVA/ST/WMRE film was analyzed based on the DPPH scavenging activity assay, which significantly increased from 29.21 ± 0.24% to 63.37 ± 4.27%. The minimum inhibitory concentration (MIC) of watermelon rind extract was analyzed for the growth inhibition of Bacillus cereus ATCC 11778, Escherichia coli ATCC 8739, and Salmonella enterica subsp. enterica serovar Typhimurium ATCC 13311, with 10% (v/v) found as an optimal concentration against B. cereus. Wrapping fresh-cut purple cabbage with PVA/ST/WMRE film significantly reduced the microbial load after 3 days of storage, in comparison to commercial packaging (PET) and thermoplastic control film. Consumer testing of the packaging film indicated that user acceptance of the product was favorable. Therefore, we suggest that this newly developed film can be used as a biodegradable food packaging item that will lead to enhanced food safety, food quality, prolonged shelf life, and consumer acceptance for further food applications.

8.
J Food Sci ; 86(9): 3778-3797, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34337757

RESUMO

Bananas (Musaceae) are one of the world's most common fruit crops and the oldest medicinal plants that are used to treat a variety of infections. There has been recent interest in elucidating the efficiency of the naturally active ingredients, particularly the antimicrobials, in this plant. This review begins with a short background of the banana plant and its cultivars as well as a brief description of its parts. Different experimental tests of the antimicrobial effects and the responsible bioactive compounds of the banana part extracts are then elaborated. A variety of recent and evolving applications of banana parts in the development of functional bakery, dairy, beverage, and meat products as a wheat substitute, fiber/prebiotic source, fat/sucrose substitute, and natural antioxidant are also discussed. Finally, the recent challenges and opportunities presented by different banana parts in creating bio-packaging materials and bactericidal nanoparticles are addressed. This plant contains a variety of antimicrobial substances, including dopamine, gentisic acid, ferulic acid, lupeol, and 3-carene. However, few studies have been conducted on its use as a bio-preservative in food products; it should also be seen as a natural source of both antimicrobial and antioxidant agents. It offers a potentially simple eco-friendly alternative to antibacterial and fungicidal agents rather than chemicals. Low cost, reliable methods for purifying these compounds from banana waste could be useful for food storage and creating more value-added bio-packaging products for perishable food goods.


Assuntos
Anti-Infecciosos , Embalagem de Alimentos , Musa , Extratos Vegetais , Anti-Infecciosos/farmacologia , Embalagem de Alimentos/métodos , Embalagem de Alimentos/tendências , Musa/química , Extratos Vegetais/farmacologia , Plantas Medicinais/química
9.
Polymers (Basel) ; 13(16)2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34451212

RESUMO

The side effects and potential impacts on human health by traditional chemical additives as food preservatives (i.e., potassium and sodium salts) are the reasons why novel policies are encouraged by worldwide public health institutes. More natural alternatives with high antimicrobial efficacy to extend shelf life without impairing the cheese physicochemical and sensory quality are encouraged. This study is a comprehensive review of emerging preservative cheese methods, including natural antimicrobials (e.g., vegetable, animal, and protist kingdom origins) as a preservative to reduce microbial cheese contamination and to extend shelf life by several efforts such as manufacturing ingredients, the active ingredient for coating/packaging, and the combination of packaging materials or processing technologies. Essential oils (EO) or plant extracts rich in phenolic and terpenes, combined with packaging conditions and non-thermal methods, generally showed a robust microbial inhibition and prolonged shelf life. However, it impaired the cheese sensory quality. Alternatives including EO, polysaccharides, polypeptides, and enzymes as active ingredients/nano-antimicrobials for an edible film of coating/nano-bio packaging showed a potent and broad-spectrum antimicrobial action during shelf life, preserving cheese quality parameters such as pH, texture, color, and flavor. Future opportunities were identified in order to investigate the toxicological effects of the discussed natural antimicrobials' potential as cheese preservatives.

10.
Foods ; 9(10)2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33036319

RESUMO

An active packaging based on pure cellulose coupled with cellulose acetate coated with layered double hydroxide (LDH), hosting 4-hydroxybenzoate (listed in EC-Directive 10/2011) as an antimicrobial agent, was formulated and realized. The release of 4-hydroxybenzoate ionically bonded to the LDH layers was much slower than the molecule freely dispersed into the coating. The capability of the active packaging to inhibit Pseudomonas, Escherichia coli, Salmonella and Lactic Bacteria was evaluated, as well as the global migration with three different food simulant (i.e., acetic acid at 3% (v/v), ethanol at 50% (v/v) and vegetable oil) that demonstrated, in compliance with the migration limits of the EU regulation, the suitability of the prepared packaging to be employed as food contact material. Ready to east cooked tomato pasta was packaged into the active trays and in uncoated, as control, up to 30 days at 4 °C. Organoleptic characteristics, mold evolution, total mesophilic aerobic counts (TBC), Enterobacteriaceae, Lactic Bacteria and Pseudomonas, and in colony forming unit per gram (CFU/g), showed a significant activity of 4-hydroxybenzoate in increasing the shelf life of the pasta ready to eat.

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