New Active Packaging Based on Biopolymeric Mixture Added with Bacteriocin as Active Compound.

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.

Developments of biobased plasticizers for compostable polymers in the green packaging applications: A review.

The demand for biobased materials for various end-uses in the bioplastic industry is substantially growing due to increasing awareness of health and environmental concerns, along with the toxicity of synthetic plasticizers such as phthalates. This fact has stimulated new regulations requiring the replacement of synthetic conventional plasticizers, particularly for packaging applications. Biobased plasticizers have recently been considered as essential additives, which may be used during the processing of compostable polymers to enormously boost biobased packaging applications. The development and utilization of biobased plasticizers derived from epoxidized soybean oil, castor oil, cardanol, citrate, and isosorbide have been broadly investigated. The synthesis of biobased plasticizers derived from renewable feedstocks and their impact on packaging material performance have been emphasized. Moreover, the effect of biobased plasticizer concentration, interaction, and compatibility on the polymer properties has been examined. Recent developments have resulted in the replacement of synthetic plasticizers by biobased counterparts. Particularly, this has been the case for some biodegradable thermoplastics-based packaging applications.

Synthesis of a Novel Chitosan/Basil Oil Blend and Development of Novel Low Density Poly Ethylene/Chitosan/Basil Oil Active Packaging Films Following a Melt-Extrusion Process for Enhancing Chicken Breast Fillets Shelf-Life.

An innovative process for the adsorption of the hydrophobic Basil-Oil (BO) into the hydrophilic food byproduct chitosan (CS) and the development of an advanced low-density polyethylene/chitosan/basil-oil (LDPE/CS_BO) active packaging film was investigated in this work. The idea of this study was the use of the BO as both a bioactive agent and a compatibilizer. The CS was modified to a CS_BO hydrophobic blend via a green evaporation/adsorption process. This blend was incorporated directly in the LDPE to produce films with advanced properties. All the obtained composite films exhibited improved packaging properties. The film with 10% CS_BO content exhibited the best packaging properties, i.e., 33.0% higher tensile stress, 31.0% higher water barrier, 54.3% higher oxygen barrier, and 12.3% higher antioxidant activity values compared to the corresponding values of the LDPE films. The lipid oxidation values of chicken breast fillets which were packaged under vacuum using this film were measured after seven and after fourteen days of storage. These values were found to be lower by around 41% and 45%, respectively, compared with the corresponding lipid oxidation values of pure LDPE film.

Liposomal Encapsulation of Carvacrol to Obtain Active Poly (Vinyl Alcohol) Films.

Lecithins of different origins and compositions were used for the liposomal encapsulation of carvacrol within the framework of the development of active films for food packaging. Liposomes were incorporated into aqueous polymeric solutions from fully (F) and partially (P) hydrolysed Poly (vinyl alcohol) (PVA) to obtain the films by casting. The particle size distribution and ζ-potential of the liposomal suspensions, as well as their stability over time, were evaluated. Liposomal stability during film formation was analysed through the carvacrol retention in the dried film and the film microstructure. Subtle variations in the size distributions of liposomes from different lecithins were observed. However, the absolute values of the ζ-potential were higher (-52, -57 mV) for soy lecithin (SL) liposomes, followed by those of soy lecithin enriched with phosphatidylcholine (SL-PC) (-43, -50 mV) and sunflower lecithin (SFL) (-33, -38 mV). No significant changes in the liposomal properties were observed during the study period. Lyotropic mesomorphism of lipid associations and carvacrol leakage occurred to differing extents during the film drying step, depending on the membrane lipid composition and surface charge. Liposomes obtained with SL-PC were the most effective at maintaining the stability of carvacrol emulsion during film formation, which led to the greatest carvacrol retention in the films, whereas SFL gave rise to the least stable system and the highest carvacrol losses. P-PVA was less sensitive to the emulsion destabilisation due to its greater bonding capacity with carvacrol. Therefore, P-PVA with carvacrol-loaded SL-PC liposomes has great potential to produce active films for food packaging applications.

Effect of the incorporation of lignin microparticles on the properties of the thermoplastic starch/pectin blend obtained by extrusion.

The present study aimed to produce thermoplastic starch films with different concentrations of thermoplastic pectin and the addition of 4% lignin microparticles as a reinforcing and active agent. The pectin improved the modulus of elasticity, and decreased the elongation at break. In addition, it improved the UV light protection to 100% at 320 nm and 95.9% at 400 nm. The incorporation of lignin microparticles improved the thermal stability of the blends made with 25% and 50% thermoplastic pectin when compared to the pectin-free blends. The blend with 25% thermoplastic pectin led to an increase of 75.8% and 34% in elongation at break and deformation of the films, respectively. This blend also improved the UV light protection to 100% due to its dark brown color. Regarding the permeability properties, the films with 25% and 50% thermoplastic pectin showed lower oxygen permeability (48% and 65%) and an increase in the antioxidant activities from 2.7% to 71.08% and 4.1% to 79.28%, respectively. Thus, the polymer blend with 25% thermoplastic pectin with the incorporation of lignin microparticles proved to be a good alternative for use in foods sensitive to the effects of oxygen and UV light.

Amylose/cellulose nanofiber composites for all-natural, fully biodegradable and flexible bioplastics.

Thermoplastic, polysaccharide-based plastics are environmentally friendly. However, typical shortcomings include lack of water resistance and poor mechanical properties. Nanocomposite manufacturing using pure, highly linear, polysaccharides can overcome such limitations. Cast nanocomposites were fabricated with plant engineered pure amylose (AM), produced in bulk quantity in transgenic barley grain, and cellulose nanofibers (CNF), extracted from agrowaste sugar beet pulp. Morphology, crystallinity, chemical heterogeneity, mechanics, dynamic mechanical, gas and water permeability, and contact angle of the films were investigated. Blending CNF into the AM matrix significantly enhanced the crystallinity, mechanical properties and permeability, whereas glycerol increased elongation at break, mainly by plasticizing the AM. There was significant phase separation between AM and CNF. Dynamic plasticizing and anti-plasticizing effects of both CNF and glycerol were demonstrated by NMR demonstrating high molecular order, but also non-crystalline, and evenly distributed 20 nm-sized glycerol domains. This study demonstrates a new lead in functional polysaccharide-based bioplastic systems.

Properties of hydric and biodegradability of cassava starch-based bioplastics reinforced with thermally modified kaolin.

In this study, hydric and biodegradability properties of cassava starch-based bioplastics reinforced with crude kaolin or treated kaolinitic clay at 700 °C called metakaolin were investigated using water adsorption and microbiological tests. Non-reinforced bioplastics (BP) and those containing 5 wt.% crude kaolin (BPKB) or metakaolin (BPMKB) were manufactured using the casting/evaporation method. Results obtained showed a decrease in the solubility and in the water diffusion and permeability of clay-reinforced bioplastics with respect to the ones without reinforcement. This improvement of the hydric properties has been attributed to the reduction in the free volumes existing between the starch macromolecules due to their interactions with clay platelets. These interactions might favor a more homogeneous and compact microstructure. The biodegradability of the clay reinforced bioplastics was significantly improved due to the bacterial proliferation. The thermal treatment of kaolinitic clay further improved the hydric and biodegradability properties of starch-based bioplastics.

Liquefaction of starch using solid-acid catalysts derived from spent coffee for the production of plasticized poly (vinyl alcohol) films.

This paper reports a strategy for preparing polyether polyols from corn starch, with (i) a mixture of polyethylene glycol 400 and glycerin (7:3, w/w) as the liquefying solvent and (ii) a spent-coffee-derived solid-acid catalyst (SC-SAC) (1:10, w/w, SC-SAC/starch) at 433 K for 1.5 h, under which conditions the liquefaction yield exceeded 99 %. The SC-SAC was prepared via hydrothermal carbonization at 453 K for 12 h, followed by sulfonation with H2SO4 at 343 K for 10 h. The liquefied starch product (SLP) was then used to plasticize poly(vinyl alcohol) (PVA) films with various mixing ratios. The optimal 0.4 SLP/PVA blend film exhibited good mechanical properties (tensile strength 38.07 MPa, elongation at break 1199 %), good transparency, and excellent flexibility. The results highlight the possibility of using SLP/PVA films in the development of degradable packaging materials.

Study on physicochemical properties, antioxidant and antimicrobial activity of okara soluble dietary fiber/sodium carboxymethyl cellulose/thyme essential oil active edible composite films incorporated with pectin.

Active edible films based on okara soluble dietary fiber (SDF), pectin, sodium carboxymethyl cellulose (CMCNa) and thyme essential oil (TEO) were successfully prepared. We aimed to exploit biodegradable edible films and realize the full utilization of waste resources. The effects of different amounts of pectin on the properties and structural characterization of the composite film with or without TEO were studied using a solution casting evaporation method. In general, the addition of TEO can improve the properties of the composite membrane. Pectin was homogeneously distributed within the films and exhibited good interaction with the polymer matrix. The addition of pectin led to significantly higher mechanical and optical properties of the composite film, compared with SDF/CMC-Na composite film. The tensile strength reached 21.419 ± 2.22 MPa, and the minimum transparency reduced to 88.9% ± 0.42%, with increasing pectin. Notably, the water resistance and oil resistance were enhanced. The composite films also possessed satisfactory antioxidant activity, with a DPPH-free radical scavenging rate of 46.33% ± 0.72%, while antibacterial activity against E. coli and S. aureus bacteria was not obvious. Antioxidant and antibacterial SDF/pectin/CMC-Na composite films with enhanced mechanical, optical and barrier properties are excellent candidates for active edible packaging.

Improved antioxidant activity of a starch and gelatin-based biodegradable coating containing Tetradenia riparia extract.

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.

Application of Nanoemulsions (W/O) of Extract of Opuntia oligacantha C.F. Först and Orange Oil in Gelatine Films.

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.

A novel glucomannan incorporated functionalized carbon nanotube films: Synthesis, characterization and antimicrobial activity.

A novel nanocomposite film was developed by incorporating functionalized carbon nanotube (PCNT) and gallic acid (GA) into carboxymethyl konjac glucomannan (CKGM) and gelatin (GL) matrix. The influences of the PCNT content on the structural, morphological, mechanical, barrier, thermal and antimicrobial properties of CKGM/GL nanocomposite film were discussed. The structure of PCNT@CKGM/GL nanocomposite film was characterized by FT-IR, SEM, and AFM. The crystal structure and thermal ability of the film were generated by XRD and TGA-DTG. The analyses of FT-IR revealed that the amide linkage and strong hydrogen bonding were formed between CKGM, GL, and PCNT. Moreover, the characterization of mechanical properties, moisture barrier, and antimicrobial activities indicated the benefits of adding PCNT into CKGM/GL films. The results suggested that the PCNT@CKGM/GL films exhibited antimicrobial activity against Staphylococcus aureus and Escherichia coli. Therefore, such antimicrobial nanocomposite films have the potential of maintaining the quality and prolong the shelf life of food products.

Bioplastic (poly-3-hydroxybutyrate) production by the marine bacterium Pseudodonghicola xiamenensis through date syrup valorization and structural assessment of the biopolymer.

Biobased degradable plastics have received significant attention owing to their potential application as a green alternative to synthetic plastics. A dye-based procedure was used to screen poly-3-hydroxybutyrate (PHB)-producing marine bacteria isolated from the Red Sea, Saudi Arabia. Among the 56 bacterial isolates, Pseudodonghicola xiamenensis, identified using 16S rRNA gene analyses, accumulated the highest amount of PHB. The highest PHB production by P. xiamenensis was achieved after 96 h of incubation at pH 7.5 and 35 °C in the presence of 4% NaCl, and peptone was the preferred nitrogen source. The use of date syrup at 4% (w/v) resulted in a PHB concentration of 15.54 g/L and a PHB yield of 38.85% of the date syrup, with a productivity rate of 0.162 g/L/h, which could substantially improve the production cost. Structural assessment of the bioplastic by Fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy revealed the presence of methyl, hydroxyl, methine, methylene, and ester carbonyl groups in the extracted polymer. The derivative products of butanoic acid estimated by gas chromatography-mass spectrometry [butanoic acid, 2-amino-4-(methylseleno), hexanoic acid, 4-methyl-, methyl ester, and hexanedioic acid, monomethyl ester] confirmed the structure of PHB. The present results are the first report on the production of a bioplastic by P. xiamenensis, suggesting that Red Sea habitats are a potential biological reservoir for novel bioplastic-producing bacteria.

Dialysis Preparation of Smart Redox and Acidity Dual Responsive Tea Polyphenol Functionalized Calcium Phosphate Nanospheres as Anticancer Drug Carriers.

Large-scale preparation of biocompatible drug delivery systems with targeted recognition and controlled release properties has always been attractive. However, this strategy has been constrained by a lot of design challenges, such as complicated steps and premature drug release. Herein, in this paper, we address these problems by a facile in situ mineralization method, which synthesizes biodegradable tea polyphenol coated monodisperse calcium phosphate nanospheres using for targeted and controlled delivery of doxorubicin. Dialysis diffusion method was used to control ion release to form mineralized nanospheres. The polyphenol coatings and calcium phosphate used in this work could be biodegraded by intracellular glutathione and acidic microenvironment, respectively, resulting the release of encapsulated drug. According to confocal fluorescence microscopy, and cytotoxicity experiments, the prepared tea polyphenol functionalized, doxorubicin loaded calcium phosphate nanospheres were confirmed to have highly efficient internalization and obvious cell killing effect on target tumor cells, but not normal cells. Our results suggest that these tea polyphenols functionalized calcium phosphate nanospheres are promising vehicles for controlled release of an anticancer drug in cancer therapy.

Physicochemical, thermal, mechanical, optical, and barrier characterization of chia (Salvia hispanica L.) mucilage-protein concentrate biodegradable films.

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.

Development and characterization of sodium alginate based active edible films incorporated with essential oils of some medicinal plants.

The aim of this study was to develop sodium alginate based active films incorporated with essential oils (EO) of R. officinalis L, A. herba alba Asso, O. basilicum L and M. pulegium L. the films were characterized in terms of bioactive properties including thickness, moisture content, water vapor and oxygen permeability, release test, mechanical, molecular, biodegradability and thermal properties. The results showed that the active films had a strong antibacterial effect against the six pathogenic bacteria with the inhibition zone between18.5 and 38.67 mm. furthermore, the antioxidant capacity of the films ranged from 4.57% to 23.09%. According to results of release test, physical, molecular, mechanical, biodegradability, thermal and barrier properties, the EOs were uniformly dispersed in the polymer matrix and improved slightly thermal (Tm) and barrier properties, while decreased tensile strength and it was obtained that this film is biodegradable in the soil. In conclusion, it could be said that sodium alginate based edible films incorporated with EO have a potential to be used food packaging applications.

Development of biodegradable sustained-release damnacanthal nanocapsules for potential application in in-vitro breast cancer studies.

The "noni" species of Morinda citrifolia L., is using in traditional medicine in the tropical country for over 2000 years. Noni fruit has come from the Morinda citrifolia tree which is called Rubiaceae, and it is from the coffee family. It is a perennial herb whose ripe fruit has a robust butyric acid smell and flavor. Recently scientists have proven that this fruit has antioxidant and antibiotic properties in vitro. An anthraquinone, damnacanthal, is one of the constituents of Morinda citrifolia. It has been demonstrated to have anti-cancer properties. Damnacanthal has low water solubility and low bioavailability. Formulating of damnacanthal into the biodegradable nanocapsule drug delivery system may increase its bioavailability. Various formulations of damnacanthal would be developed to enable the selection of a dosage form that could offer the provision of the anti-cancer bioactive substance with suitable sustained- or controlled release properties. The efficiency of extraction of damnacanthal will be compared using both conventional and traditional method. Both the damnacanthal and an anthraquinone active compounds extracted from noni roots, are currently being studied in the context of anti-cancer study. Soon, the medical values, bioactivities and nutritional of this fruit can be assessed, especially its anti-cancer activity, this fruit extract could play an outstanding economic role in Malaysia and other tropical countries.

Cellulose nanocrystals-starch nanocomposites produced by extrusion: Structure and behavior in physiological conditions.

Different amounts of cellulose nanocrystals (CNCs) were added to glycerol-plasticized thermoplastic starch (TPS) to obtain bio-based nanocomposites. First, nanocomposites are prepared by extrusion and their structure is studied at different scales using WAXS (Wide Angle X-ray Scattering) and solid-state NMR (Nuclear Magnetic Resonance) for local/crystalline organization, AF4 (Asymmetrical Flow Field-Flow Fractionation) for molecular weight and chain length, and SEM (Scanning Electron Microscopy) for the morphology at a larger scale. Then, relevant mechanical properties and behavior in physiological conditions (swelling, enzymatic degradation) are characterized. The results show that the incorporation of cellulose nanocrystals up to 2.5 wt% causes a mechanical reinforcement as determined by DMTA (Dynamic Mechanical Thermal Analysis) and reduces the swelling and the enzymatic degradation of the materials compared to reference TPS. This could be linked to the formation of starch-cellulose hydrogen and hydroxyl bonds. Conversely, above 5 wt% CNC content nanocrystals seem to aggregate which in turn worsens the behavior in physiological conditions.

Subcutaneous vaccination using injectable biodegradable hydrogels for long-term immune response.

Prolonged vaccine release enables gradual immunostimulation, providing long-term immunity. Herein, Vitamin E-PEG-Vitamin E triblock 'ABA' hydrogel, which is formed through physical cross-linking of flower-shaped micelles and can reside in vivo for >17 weeks, was employed for delivery of cancer preventive vaccines to provide sustained anticancer immunity. Mice vaccinated with hydrogel formulations produced a significantly higher quantity of antibodies compared to solution formulations. OVA was used to study EG.7-OVA tumor rejection in vaccinated mice. Among all formulations, OVA-loaded hydrogel containing aluminum-based adjuvant had the best therapeutic outcome, and only 2/10 mice developed solid tumors with significantly smaller tumor size. Moreover, no adverse effect on liver and kidney was detected with the hydrogel formulation. In a lymphoma metastasis mouse model, vaccination with the OVA-loaded hydrogel and adjuvant resulted in increased survival (66.7%) compared to other formulations (12.5-50%) over 100 days. This hydrogel is a promising formulation for sustained delivery of vaccines.

Electrospun PCL nanofibers blended with Wattakaka volubilis active phytochemicals for bone and cartilage tissue engineering.

In the present study, the polycaprolactone (PCL) nanofibers were investigated as a carrier to deliver phytochemicals for bone and cartilage tissue engineering. The PCL nanofibers was blended with phytochemicals hexadecanoic acid, octadecanoic acid and N,N-diisopropyl (2,2,3,3,3-pentafluoropropyl) amine isolated from a medicinal plant, Wattakaka volubilis. The scaffolds were characterized using scanning electron microscope (SEM) and Fourier transform infrared (FTIR) spectroscopy. The average diameter of control and phytochemical loaded nanofiber was 208 ±â€¯9.6 nm and 316 ±â€¯7.0 nm respectively. Biodegradation rate of nanofibers, impact of nanofiber on meniscus and osteoblast cell growth was analyzed using 3-(4,5-dimethyl thiazolyl-2)-2,5-diphenyl tetrazolium bromide (MTT) assay, DNA content and extra cellular matrix secretion. Hoechst stain and SEM images were used to visualize and monitor the cell growth on PCL scaffold. The phytochemicals incorporated PCL nanofibers enhanced the growth and proliferation of primary human meniscus and osteoblast like cells and hence may be suitable scaffold for bone and cartilage tissue engineering applications.