Chitosan and gelatin based biodegradable packaging films with UV-light protection

Electrospun Gelatin Nanocontainers for Enhanced Biopharmaceutical Performance of Piroxicam: In Vivo and In Vitro Investigations

BACKGROUND

Piroxicam exhibits low oral bioavailability, due to its meager solubility in water. The intent of this study was to ameliorate the bioavailability of the drug by employing a solubility-enhancing encapsulation technique.

METHODS

Seven samples were formulated with piroxicam and gelatin using both solvent evaporation and electrospraying together. Evaluation of solubility and release rate in water and assessment of bioavailability in rats were carried out in comparison with piroxicam plain drug powder (PPDP). Other in vitro explorations were accomplished using powder X-ray diffraction analysis, differential scanning calorimetry, thermogravimetric analysis, scanning electron microscopy, and Fourier-transform infrared spectroscopy.

RESULTS

All piroxicam-loaded gelatinnanocontainers (PLGNs) enhanced solubility and release of the payload in water. In particular, a PLGN formulation consisting of piroxicam and gelatin at a 1:8 (w:w) ratio presented about 600-fold the drug solubility of that shown by PPDP. Moreover, 85.12%±10.96% of the payload was released from this formulation in 10 minutes which was significantly higher than that dissolved from PPDP in 10 minutes (11.81%±5.34%). Drug content, drug loading, and encapsulation efficiency of this formulation were 93.41%±0.56%, 10.45%±0.06%, and 66.74%±6.87%, respectively. The drug loaded in PLGNs existed in the amorphous state, as confirmed by X-ray diffraction and differential scanning-calorimetry analyses, and was more stable when analyzed by thermogravimetric analysis. Moreover, Fourier-transform infrared spectroscopy analysis suggested nonexistence of any piroxicam-gelatin interaction in the formulation. In the scanning electron-microscopy image, PLGNs appeared as round, smooth particles, with particle size of <1,000 nm. Amelioration in bioavailability of piroxicam with the aforementioned PLGN formulation was fourfold that of PPDP.

CONCLUSION

The PLGN formulation fabricated with piroxicam and gelatin at 1:8 (w:w) might be a promising system for enhanced biopharmaceutical performance of the drug.

Dexamethasone- loaded polymeric porous sponge as a direct pulp capping agent

This study aims to achieve the principles of tissue engineering using biopolymers to be applied in the field of vital endodontic treatment to stimulate stem cells and engineering and regeneration of dentin tissue. the polymer blend was loaded with the steroidal anti-inflammatory drug, dexamethasone, and the porous drug-loaded bio-sponge was produced by lyophilization. Bio-sponge, as a direct pulp capping agent, was histologically studied compared to calcium hydroxide Ca(OH)₂ in an animal experiment. The results indicated the effectiveness of the bio-sponge as a direct pulp capping agent where the dentin bridge was formed faster than Ca(OH)₂ treated samples. There was no inflammatory response in the pulp tissue throughout the follow-up period. The porous bio-sponge loaded with dexamethasone with a neutral pH resulted in enhancement of the odontoblast differentiation from stem cells, resulting in the formation of a renewed dentin bridge without the slightest inflammatory response in the pulp.

Conception of novel blue crab chitosan films crosslinked with different saccharides via the Maillard reaction with improved functional and biological properties

This work aimed to modify blue crab chitosan-based films through the Maillard reaction (MR) as a novel alternative to improve their functional and biological properties. To this end, different saccharides (glucose (aldohexose), fructose (ketohexose), xylose (aldopentose) and arabinose (aldopentose)), at different weight ratios 0.5, 1.0 and 2.0 % (g/100 g polymer), were studied, and films were heated at 90 °C for 24 h. Based on color changes and browning index measurements, the extent of MR was the highest with aldopentoses, whereas hexoses and particularly ketohexoses, exhibited a relative crosslinking rate. These findings were further reflected with an improvement in treated films mechanical properties and thermal degradation temperatures, and advantageously, barrier properties against UV light and water. In addition, the MR-modified Cs-based films antioxidant activity was interestingly enhanced with mainly aldopentoses. Consequently, MR crosslinked chitosan-based films are promising alternative for active and functional packaging able of food oxidation hindering, especially using aldopentoses.

Characterization of whey protein-based films incorporated with natamycin and nanoemulsion of α-tocopherol

Food packaging materials are commonly derived from petroleum that increases global contamination; this raises the interest to evaluate raw material from renewable sources such as whey protein for the development of packaging materials, especially to produce active films. This research aimed to evaluate whey protein-based film properties when natamycin, nanoemulsioned α-tocopherol, or both were added. An oil-in-water (O/W) nanoemulsion of antioxidant (α-tocopherol) was prepared by microfluidization technique. Four films were prepared with different levels of natamycin and nanoemulsified α-tocopherol and were characterized in terms of physicochemical, mechanical, optical-properties, water vapor barrier, FTIR, microstructure, antioxidant and antimicrobial activity. The natamycin, nanoemulsified α-tocopherol, or both did not modify the moisture content of the films. Moreover lead to a significant reduction of tensile strength and elastic modulus, while presenting growth in the elongation at break. Film opacity, the total color difference, the UV-Vis light barrier, and the water vapor permeability values increased when compounds were incorporated into the film. The microstructure studies showed uniformly distributed porosity throughout the films. The addition of nanoemulsioned α-tocopherol into whey protein-based films provoked antioxidant activity and the addition of natamycin produced films with effectivity against C. albicans, P. chrysogenum, and S. cerevisiae, allowing develop a material appropriate for use as active food packaging.

Biodegradability assessment of starch/glycerol foam and poly(butylene adipate-co-terephthalate)/starch film by respirometric tests

Abstract The objectives of this work were to determine the biodegradability of starch/glycerol foam and of poly(butylene-adipate-co-terephthalate) (PBAT)/starch film using respirometric methods and also to compare these results with conventional polymers – expanded polystyrene and low-density polyethylene. A matured organic compost was utilized as inoculum and sucrose was used as positive reference material. Biodegradation efficiencies (BE) after 47 days were: 35% for sucrose; 34% for starch/glycerol; and 38% for PBAT/starch. Starch/glycerol and PBAT/starch presented BE statistically equal to sucrose, whilst both the conventional packaging used were not degraded (p> 0.05). Infrared spectroscopy and thermogravimetric analyses showed that the microbiota rather degraded the starch over the PBAT in the PBAT/starch blend, and also that some starch remained intact in the internal polymeric matrix. This study verified that starch/glycerol foam and PBAT/starch film are highly biodegradable materials and may then be used to enhance the biodegradability of some products such as disposable trays and supermarket bags.

Chitosan–Starch Films Modified with Natural Extracts to Remove Heavy Oil from Water

Chitosan films were used to remove heavy oil from connate water, deionized water, and seawater. In this research, chitosan–starch films were modified with natural extracts from cranberry, blueberry, beetroot, pomegranate, oregano, pitaya, and grape. These biodegradable, low-cost, eco-friendly materials show an important oil sorption capacity from different water conditions. It was observed that the sorption capacity has a clear correlation with the extract type, quantity, and water pH. In order to understand the physical and chemical properties of the films, they were analyzed according to their apparent density, water content, solubility, and swelling degree by scanning electron microscopy (SEM), thermogravimetric analysis (TGA), gas chromatography–mass spectroscopy (GC–MS), and the determination of surface area using the Brunauer Emmett Teller (BET) method. The results indicate that chitosan–starch films modified with natural extracts can be successfully applied for environmental issues such as oil spill remedy.

UV-shielding alginate films crosslinked with Fe3+ containing EDTA

In this study, we fabricated a soft, transparent UV-shielding film (Alg-Fe³⁺-EDTA) by crosslinking sodium alginate with a ferric ion solution containing EDTA. The obtained films were characterized via SEM, ATR-FTIR, XRD, TG and DTG; the results indicated that the synergistic gelation of ferric alginate and alginic acid existed in Alg-Fe³⁺-EDTA film. The Alg-Fe³⁺-EDTA film performance to be optimized under the following conditions: 1.6% Fe³⁺, 0.8% EDTA, and crosslinking duration of 12 min. The Alg-Fe³⁺-EDTA film had high visible light transmittance, the UV-C (200-280 nm) and UV-B (280-315 nm) shielding rates were 100%, and the UV-A (315-400 nm) shielding rate was 98.37%; the UPF reached 50+; additionally, the tensile strength and elongation-at-break were 56.85 MPa and 10.45%, respectively, and still have ultraviolet shielding effect under water environments or after strong light irradiation. This work provides an efficient method to improve the optical and mechanical ability of ferric alginate films.

Preparation and Characterization of Chitosan-Based Ternary Blend Edible Films with Efficient Antimicrobial Activities for Food Packaging Applications

To improve the mechanical and antibacterial properties of chitosan (CS) films, a ternary blend edible film was prepared by incorporating CS, gelatin (GE), and natural cinnamon essential oil (CEo). Scanning electron microscopy (SEM), Atomic force microscopy (AFM), Fourier transform infrared spectroscopy, and X-ray diffraction were performed to evaluate the films. The mechanical properties, light transmission, thermal stability, hydrophilicity, and antibacterial activity of the films were also determined. The results confirmed all of the films exhibited excellent UV protection with low transparency at 600 nm. Compared with the CS films, the ternary composite film (CSGEo film, containing CS, GE, and CEo) had a higher elongation at break but a lower tensile strength. SEM images revealed that all films had smooth surfaces, although some obvious differences between CS and CSGEo films were observed by AFM. Additionally, the incorporation of GE and CEo to the films enhanced their thermal stability and contact angle, but decreased their crystallinity and wettability. The antimicrobial activity results showed that CSGEo films had excellent antimicrobial activity against Escherichia coli and Staphylococcus aureus, for which the antibacterial rate exceeded 98%. The minimum inhibitory concentrations of the CSGEo solution against E. coli and S. aureus were both 52.06 µg/mL, and the minimal bactericidal concentrations were 104.12 and 52.06 µg/mL, respectively. These results suggest that CSGEo films possess good mechanical and antibacterial properties, and therefore, their application in the food packaging industry is promising. PRACTICAL APPLICATION: The main raw materials of the edible films developed in this study are aquatic by-products, so the films are edible and biodegradable. The addition of gelatin and CEo improved the UV barrier and thermal properties but decreased the crystallinity and hydrophilicity of the films, making them suitable for use as packaging materials. CEo-incorporated films exhibited excellent mechanical properties and antibacterial activity and can, therefore, be used in the food packaging industry.

Synthesis, characterization and application of gelatin-carboxymethyl cellulose blend films for preservation of cherry tomatoes and grapes

In the present study, gelatin-carboxymethyl cellulose blend film was synthesized, characterized and applied for the first time to preserve cherry tomatoes (Solanum lycopersicum var. cerasiforme) and grapes (Vitis vinifera). Gelatin (Gel) film forming solution was incorporated with carboxymethyl cellulose (CMC) at three volume per volume (Gel:CMC) ratios, namely 75:25, 50:50 and 25:75. CMC treatment has improved the transparency, tensile strength (TS), elongation at break (EAB), water vapor permeability and oxygen permeability of gelatin films. A pronounced effect was obtained for 25Gel:75CMC film. The TS and EAB values were increased from 25.98 MPa and 2.34% (100Gel:0CMC) to 37.54 MPa and 4.41% (25Gel:75CMC), respectively. A significant improvement in antimicrobial property of gelatin films against two food pathogens, namely Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) was obtained in the presence of CMC. The effectiveness of gelatin-CMC blend films to extend the shelf life of agricultural products was evaluated in a 14-day preservation study. The gelatin-CMC films were successfully controlled the weight loss and browning index of the fruits up to 50.41% and 31.34%, respectively. Overall, gelatin-CMC film is an environmental friendly film for food preservation.

Composite Films with UV-Barrier Properties Based on Bacterial Cellulose Combined with Chitosan and Poly(vinyl alcohol): Study of Puncture and Water Interaction Properties

The present study describes the preparation and characterization of composite films from bacterial cellulose produced by Komagataeibacter xylinus combined with poly(vinyl alcohol) and chitosan. The unique bacterial cellulose structure provides an expanded surface area with high porosity, easing the combination with other soluble polymers by dipping. This blending method effectively reinforces the bacterial cellulose structure. Toughness, puncture strength, water solubility, and swelling degree were measured to assess the effect of poly(vinyl alcohol) and chitosan on the analyzed properties. The morphology and optical and thermal properties were evaluated by scanning electron microscopy, UV-vis spectral analysis, thermogravimetry, and differential scanning calorimetry, respectively. Results showed that the films have good UV-barrier properties and high thermal stability. Toughness values ranged from 0.26 to 7.18 MJ/m³, burst strength ranged from 58.88 to 3234.62 g, and distance to burst ranged from 0.39 to 3.24 mm. Poly(vinyl alcohol) affected the water solubility and increased the swelling degree.

Furcellaran/gelatin hydrolysate/rosemary extract composite films as active and intelligent packaging materials

The study investigated the active and intelligent properties of films based on furcellaran (FUR), gelatin hydrolysate (GELH) and rosemary extract (from fresh leaves (FRE) and dry leaves (DRE)). Rosemary extracts were blended with FUR/GELH film forming solution at different three concentrations (5, 10, 20%). Analyzing the ζ-potential dependences of complexation polysaccharide-protein hydrolysate, we selected optimal ratio for the film formation. The introduction of rosemary extracts into FUR/GELH films increased thickness, water content and tensile strength. The UV barrier properties of tested films improved with the addition of rosemary extracts into FUR/GELH matrix. The antioxidant activity (DPPH and FRAP) did not improved with the addition of FRE but significantly increased with the addition of DRE, reaching 88% of DPPH inhibition and 207 of μmol Trolox/g of dried film of FRAP value. The color changes in different pH were observed, however, the fish spoilage test showed that those films are not suitable as intelligent films for monitoring freshness of this type of food product. Among all films tested, FUR/GELH film with 20% DRE exhibited the best performance. The obtained results suggested that FUR/GELH films with 20% DRE could be used as a promising active food packing material.

Preparation and Properties of Sodium Carboxymethyl Cellulose/Sodium Alginate/Chitosan Composite Film

A sodium alginate/chitosan solution was prepared by dissolving sodium alginate, chitosan, and glycerol in an acetic acid solution. This solution was then combined with a sodium carboxymethyl cellulose solution and the mixture was cast onto a glass plate and dried at a constant temperature of 60 °C. Then, a carboxymethyl cellulose/sodium alginate/chitosan composite film was obtained by immersing the film in a solution of a cross-linking agent, CaCl2, and air-drying the resulting material. First, the most advantageous contents of the three precursors in the casting solution were determined by a completely random design test method. Thereafter, a comprehensive orthogonal experimental design was applied to select the optimal mass ratio of the three precursors. The composite film obtained with sodium alginate, sodium carboxymethyl cellulose, and chitosan contents of 1.5%, 0.5%, and 1.5%, respectively, in the casting solution displayed excellent tensile strength, water vapor transmission rate, and elongation after fracture. Moreover, the presence of chitosan successfully inhibited the growth and reproduction of microorganisms. The composite film exhibited antibacterial rates of 95.7% ± 5.4% and 93.4% ± 4.7% against Escherichia coli and Staphylococcus aureus, respectively. Therefore, the composite film is promising for antibacterial food packaging applications.

Film-forming ability of collagen hydrolysate extracted from leather solid wastes with chitosan

Discharges of huge quantities of leather solid wastes by leather industries and the increased use of synthetic packaging films have raised serious concerns on account of their environmental impacts. The paper focuses on the development and characterization of potential environmentally friendly composite films using collagen hydrolysate (CH) extracted from leather solid wastes and chitosan (C) to assess the feasibility of producing polymeric materials suitable for applications in packaging and wrapping purposes. Solid collagen-based protein hydrolysate was extracted from chromium-tanned leather wastes and analyzed to determine its chemical properties. With the goal of improving the physico-chemical performance of CH, three types of composite films (CH75/C25, CH50/C50, CH25/C75) were prepared with increasing concentrations of C, and some of their physical and functional properties were characterized. The results indicated that the addition of C caused increase (p < 0.05) in the thickness, tensile strength (TS), elasticity modulus (EM), and water vapor permeability (WVP), leading to stronger films as compared with CH film, but significantly (p < 0.05) decreased the elongation at break (EAB) and solubility of films (p < 0.05). The light barrier measurements present low values of transparency at 600 nm of the CH/C films, indicating that the films are very transparent and they have excellent barrier properties against UV light. The structural properties investigated by FTIR and DSC showed total miscibility between both polymers. Scanning electron micrographs revealed that CH/C composite films showed a compact homogeneous structure. These results demonstrate the potential application of CH/C composite films in packaging industry.

Chitosan-Starch Films with Natural Extracts: Physical, Chemical, Morphological and Thermal Properties

The aim of this study is to analyze the properties of a series of polysaccharide composite films, such as apparent density, color, the presence of functional groups, morphology, and thermal stability, as well as the correlation between them and their antimicrobial and optical properties. Natural antioxidants such as anthocyanins (from cranberry; blueberry and pomegranate); betalains (from beetroot and pitaya); resveratrol (from grape); and thymol and carvacrol (from oregano) were added to the films. Few changes in the position and intensity of the FTIR spectra bands were observed despite the low content of extract added to the films. Due to this fact, the antioxidants were extracted and identified by spectroscopic analysis; and they were also quantified using the Folin-Denis method and a gallic acid calibration curve, which confirmed the presence of natural antioxidants in the films. According to the SEM analysis, the presence of natural antioxidants has no influence on the film morphology because the stretch marks and white points that were observed were related to starch presence. On the other hand, the TGA analysis showed that the type of extract influences the total weight loss. The overall interpretation of the results suggests that the use of natural antioxidants as additives for chitosan-starch film preparation has a prominent impact on most of the critical properties that are decisive in making them suitable for food-packing applications.