38 research outputs found
Seasonal Changes in Chemical Profile and Antioxidant Activity of Padina pavonica Extracts and Their Application in the Development of Bioactive Chitosan/PLA Bilayer Film
Seaweeds are a potentially sustainable source of natural antioxidants that can be used in
the food industry and possibly for the development of new sustainable packaging materials with the
ability to extend the shelf-life of foods and reduce oxidation. With this in mind, the seasonal variations
in the chemical composition and antioxidant activity of brown seaweed (Padina pavonica) extracts were
investigated. The highest total phenolic content (TPC) and antioxidant activity (measured by ferric
reducing/antioxidant power (FRAP), 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging,
and oxygen radical absorbance capacity (ORAC)) were found for P. pavonica June extract. The
TPC of 26.69 1.86 mg gallic acid equivalent/g, FRAP of 352.82 15.41 mole Trolox equivalent
(TE)/L, DPPH of 52.51 2.81% inhibition, and ORAC of 76.45 1.47 mole TE/L were detected.
Therefore, this extract was chosen for the development of bioactive PLA bilayer film, along with
chitosan. Primary or quaternary chitosan was used as the first layer on polylactic acid (PLA) films.
A suspension of chitosan particles with entrapped P. pavonica extract was used as the second layer.
X-ray photoelectron spectroscopy confirmed the presence of layers on the material surface. The
highest recorded antioxidant activity of the newly developed films was 63.82% inhibition. The
developed functional films exhibited antifogging and antioxidant properties, showing the potential
for application in the food industry.PRIMA program under project BioProMedFood 1467European Commissio
Chitosan-tripolyphosphate nanoparticles designed to encapsulate polyphenolic compounds for biomedical and pharmaceutical applications - A Review
Plant-based polyphenols are natural compounds, present in fruits and vegetables. During recent years, polyphenols have gained special attention due to their nutraceutical and pharmacological activities for the prevention and treatment of human diseases. Nevertheless, their photosensitivity and low bioavailability, rapid metabolism and short biological half-life represent the major limitations for their use, which could be overcome by polyphenols encapsulation (flavonoids and non-flavonoids) into chitosan (CS)-tripolyphosphate (TPP) based nanoparticles (NP). In this review, we particularly focused on the ionic gelation method for the NP design. This contribution exhaustively discusses and compares results of scientific reports published in the last decade referring to ionic gelation applied for the protection, controlled and site-directed delivery of polyphenols. As a consequence, CS-TPP NP would constitute true platforms to transport polyphenols, or a combination of them, to be used for the designing of a new generation of drugs or nutraceuticals.Fil: Di Santo, Mariana Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; ArgentinaFil: D' Antoni, Cecilia Luciana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Domínguez Rubio, Ana Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Alaimo, Agustina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Perez, Oscar Edgardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; Argentin
Kraft Lignin/Tannin as a Potential Accelerator of Antioxidant and Antibacterial Properties in an Active Thermoplastic Polyester-Based Multifunctional Material
This research focuses on key priorities in the field of sustainable plastic composites that will lead to a reduction in CO2 pollution and support the EU\u27s goal of becoming carbon neutral by 2050. The main challenge is to develop high-performance polyphenol-reinforced thermoplastic composites, where the use of natural fillers replaces the usual chemical additives with non-toxic ones, not only to improve the final performance but also to increase the desired multifunctionalities (structural, antioxidant, and antibacterial). Therefore, poly (lactic acid) (PLA) composites based on Kraft lignin (KL) and tannin (TANN) were investigated. Two series of PLA composites, PLA-KL and PLA-TANN, which contained natural fillers (0.5%, 1.0%, and 2.5% (w/w)) were prepared by hot melt extrusion. The effects of KL and TANN on the PLA matrices were investigated, especially the surface physicochemical properties, mechanical properties, and antioxidant/antimicrobial activity. The surface physicochemical properties were evaluated by measuring the contact angle (CA), roughness, zeta potential, and nanoindentation. The results of the water contact angle showed that neither KL nor TANN caused a significant change in the wettability, but only a slight increase in the hydrophilicity of the PLA composites. The filler loading, the size of the particles with their available functional groups on the surfaces of the PLA composites, and the interaction between the filler and the PLA polymer depend on the roughness and zeta potential behavior of the PLA-KL and PLA-TANN composites and ultimately improve the surface mechanical properties. The antioxidant properties of the PLA-KL and PLA-TANN composites were determined using the DPPH (2, 2\u27-diphenyl-1-picrylhydrazyl) test. The results show an efficient antioxidant behavior of all PLA-KL and PLA-TANN composites, which increases with the filler content. Finally, the KL- and PLA-based TANN have shown resistance to the Gram-negative bacteria, E. coli, but without a correlation trend between polyphenol filler content and structure
Functional Coatings for Food Packaging Applications
The food packaging industry is experiencing one of the most relevant revolutions associated with the transition from fossil-based polymers to new materials of renewable origin. However, high production costs, low performance, and ethical issues still hinder the market penetration of bioplastics. Recently, coating technology was proposed as an additional strategy for achieving a more rational use of the materials used within the food packaging sector. According to the packaging optimization concept, the use of multifunctional thin layers would enable the replacement of multi-layer and heavy structures, thus reducing the upstream amount of packaging materials while maintaining (or even improving) the functional properties of the final package to pursue the goal of overall shelf life extension. Concurrently, the increasing requirements among consumers for convenience, smaller package sizes, and for minimally processed, fresh, and healthy foods have necessitated the design of highly sophisticated and engineered coatings. To this end, new chemical pathways, new raw materials (e.g., biopolymers), and non-conventional deposition technologies have been used. Nanotechnology, in particular, paved the way for the development of new architectures and never-before-seen patterns that eventually yielded nanostructured and nanocomposite coatings with outstanding performance. This book covers the most recent advances in the coating technology applied to the food packaging sector, with special emphasis on active coatings and barrier coatings intended for the shelf life extension of perishable foods
Development of antioxidant/antimicrobial active packaging for food preservation
Changes in consumer demand, industrial production trends (such as fresh, tasty, and convenient food products), retailing practices (such as transregional and transnational long-distance sales of food), and customer lifestyles (such as a fast-paced lifestyle resulting in less time spent shopping for fresh food at the market and cooking) are the main forces driving the evolution of novel and innovative packaging techniques that maintain and monitor food safety and quality, extend shelf-life, and reduce the environmental impact of food packaging. For this purpose, the aim of the PhD project was to develop biopolymer-based active packaging to extend the shelf-life of perishable foods. Three film forming technologies were investigated: casting, rod coater coating, and extrusion.
The results of the first part of the work, related to the production of active film by casting technology, showed that among tested biopolymers, blends based on chitosan and sodium caseinate and whey protein, gelatin and inulin were good substrates for dispersing rosemary essential oil and lactic acid bacteria producing bacteriocin, respectively. On the contrary, the only biopolymer able to properly include an antioxidant polyphenol, the gallic acid, selected on the base of the antioxidant capacity, was the sodium caseinate. The addition of the active compound allowed to improve the functional properties (antioxidant or antimicrobial) of the film, without significantly affecting its physical properties. In addition, in the case of lactic acid bacteria, an improvement in the mechanical properties of the films were also observed. The active film based on chitosan, sodium caseinate and rosemary essential oil were also applied to meat burgers and it showed promising results in terms of shelf-life extension, due to reduction of lipid oxidation. The second part of the work was aimed to develop active films by using the rod coater technology. Thus, the active biopolymer solution investigated in the first part of the work were also used as a coating for commercial packaging films. Results showed the biopolymer solution can be properly used as coating on PLA or PBS films with no need to modify the film surface, thanks to its hydrophilic nature. The realized films were used to make packages for two food matrices (hazelnut-based creams and grated Grana Padano cheese) and the results showed that although there are some protective effects on oxidation kinetics, the amount of active substance conveyed using this active film technique is very low and many layers would have to be made to obtain significant results. However, the technology proved to be very flexible and with possible strengths to be explored further.
The third possibility studied for the development of active films was to include the active substance in the production phase of the packaging film. As a case study, a matrix based on Poly (3-hydroxybutyrate-co-3-hydroxyvalerate (PHBV) was investigated, in which gallic acid enriched with a chemical base, previously selected for its antioxidant and oxygen-absorbing properties, was added during the dry mixing phase. The results of release tests in food simulants and the antioxidant activity of the film confirmed that the films can be successfully applied to fatty food products to extend their shelf-life. However, the addition of the active substance has a negative effect on the structure of PHBV-based films, increasing their porosity and reducing their oxygen barrier properties. Mathematical modelling approach was used to design the active packaging by quantifying the oxygen scavenger capacity and the kinetic of adsorption of the active compound. The model was used to predict the changes of oxygen in a packaging headspace once the active compound was included in the material. Some limitations of the model were highlighted due to the film structure modification induced by the active compound which negatively affected the gas transport diffusivity. Thus, production technology must be optimized to properly apply the active film as food packaging
GREEN BIOSYNTHESIS OF ZnO NANOPARTICLES USING AGRO-WASTE AND THEIR ANTIBACTERIAL AND ANTIOXIDANT ACTIVITY
Metal oxide nanomaterials have gained a lot of attention during last decades due to their potential applications in wastewater treatment, energy storage, sensors, food packaging, etc. To date, these materials have been synthesized by different chemical and physical techniques. However many of them employ environmentally unfriendly solvents and toxic chemical compounds. To tackle this problem, use of renewable biomass such as plants and fungi as reducing or stabilizing agents in green synthesis has been considered as more sustainable option compared to toxic chemical compounds. These biological substances also behave as capping agent, which control the size and the shape of the nanoparticles. In this work, ZnO nanoparticles (NPs) have been prepared via simple, low cost and ecofriendly method using citrus fruit peel and extracts, Agaricus bisporus powder and extract as biological reducing agents. Zinc nitrate and zinc acetate were used as source of zinc ions. Structural and optical properties were investigated by X-ray diffraction analysis (XRD), Zeta potential, Fourier Transform Infrared (FTIR) spectroscopy, UV-visible (UV-vis) spectroscopy and Photoluminescence spectroscopy (PL). Morphological features were characterized by Field Emission Scanning Electron microscopy (FESEM) and High Resolution Transmission Electron Microscopy (HRTEM). Antibacterial and antioxidant activity was tested and evaluated
Chapter 34 - Biocompatibility of nanocellulose: Emerging biomedical applications
Nanocellulose already proved to be a highly relevant material for biomedical
applications, ensued by its outstanding mechanical properties and, more importantly, its biocompatibility. Nevertheless, despite their previous intensive
research, a notable number of emerging applications are still being developed.
Interestingly, this drive is not solely based on the nanocellulose features, but also
heavily dependent on sustainability. The three core nanocelluloses encompass
cellulose nanocrystals (CNCs), cellulose nanofibrils (CNFs), and bacterial nanocellulose (BNC). All these different types of nanocellulose display highly interesting biomedical properties per se, after modification and when used in
composite formulations. Novel applications that use nanocellulose includewell-known areas, namely, wound dressings, implants, indwelling medical
devices, scaffolds, and novel printed scaffolds. Their cytotoxicity and biocompatibility using recent methodologies are thoroughly analyzed to reinforce their
near future applicability. By analyzing the pristine core nanocellulose, none
display cytotoxicity. However, CNF has the highest potential to fail long-term
biocompatibility since it tends to trigger inflammation. On the other hand, neverdried BNC displays a remarkable biocompatibility. Despite this, all nanocelluloses clearly represent a flag bearer of future superior biomaterials, being
elite materials in the urgent replacement of our petrochemical dependence
Advances in Hydrogels
Hydrogels are a class of soft materials with crosslinked network structures. They show good biocompatibility, biodegradability, hydrophilicity, and mechanical properties similar to those of tissue, so they have a wide range of applications. In recent years, a variety of multifunctional hydrogels with excellent performance have been developed, greatly expanding the depth and breadth of their applications. This book is the reprint of the Special Issue “Advances in Hydrogels”, which focused on the recent advances regarding hydrogels, aiming to provide reference for researchers in related fields. This book included one editorial, thirteen original research articles, and three valuable reviews from thirteen different countries including Canada, China, Thailand, Mexico, India, Saudi Arabia, Chile, Germany, the Czech Republic, Colombia, Romania, Israel, and the USA