Physicochemical, Antioxidant, In Vitro Release, and Heat Sealing Properties of Fish Gelatin Films Incorporated with β-Cyclodextrin/Curcumin Complexes for Apple Juice Preservation

Enhancing the solubility and potency of tetrahydrocurcumin as an anti-cancer agent using a β-cyclodextrin inclusion complex approach

Curcuminoids originating from turmeric roots are renowned for their diverse pharmacological applications, particularly as a natural anticancer agent. Unfortunately, harnessing the full potential of curcumin derivatives in cancer therapy has been impeded by its inherent limitations, specifically instabilities owing to poor solubility, leading to low systemic bioavailability under normal physiological circumstances. To circumvent this, a novel organic-based drug delivery system employing physically adsorbed β-cyclodextrin (βCD) as an excipient was developed in this study. This resulted in improved aqueous dispersion coupled with anticancer enhancements of tetrahydrocurcumin (THC) at a molar ratio of 2:1. Encapsulation of this agent was confirmed by physicochemical characterisation using UV-vis spectroscopy, differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and both in vitro and in vivo approaches. Through the presence of an inclusion complex, a higher aqueous dispersion (65-fold) resulting in a higher drug content and an elevated release profile was achieved. Athymic nude (Nu/Nu) mice exposed to this treatment displayed improvements in tumour regression compared to stand-alone agents, consistent with in vitro cytotoxicity assays with an SI value > 10. The inclusion complex further enhanced apoptosis, as well as anti-migration and anti-invasion rates. Mechanistically, this formulation was consistent in terms of caspase 3 activation. Furthermore, the inclusion complex exhibited reduced systemic toxicity, including reduced inflammation in vital organs as examined by hematoxylin and eosin (H&E) staining. This study also revealed a notable sequential reduction in serum levels of tumour markers, including carcinoembryonic antigen (CEA) and mouse Cytochrome P450 1A2 (CYP1A2), correlating with a significant decrease in tumour bulk volume upon treatment commencement. These compelling findings highlight the potential of this formulation to empower insoluble or poorly soluble hydrophobic agents, thus offering promising prospects for their effective utilisation in colorectal cancer (CRC) chemotherapy.

Food applications of bioactive biomaterials based on gelatin and chitosan

Food packaging must guarantee the products' quality during the different operations including packing and maintenance throughout transportation and storage until to consumption. Thus, it should satisfy, both, food freshness and quality preservation and consumers health safety. Natural bio-sourced polymers have been explored as safe edible materials for several packaging applications, being interestingly carrier of bioactive substances, once added to improve films' properties. Gelatin and chitosan are among the most studied biomaterials for the preparation of edible packaging films due to their excellent characteristics including biodegradability, compatibility and film-forming property. These polymers could be used alone or in combination with other polymers to produce composite films with the desired physicochemical and mechanical properties. When incorporated with bioactive substances (natural extracts, polyphenolic compounds, essential oils), chitosan/gelatin-based films acquired various biological properties, including antioxidant and antimicrobial activities. The emerging bioactive composite films with excellent physical attributes represent excellent packaging alternative to preserve different types of foodstuffs (fruits, meat, fish, dairy products, …) and have shown great achievements. This chapter provides the main techniques used to prepare gelatin- and chitosan- based films, showing some examples of bioactive compounds incorporated into the films' matrix. Also, it illustrates the outstanding advantages given by these biomaterials for food preservation, when used as coating and wrapping agents.

A tear-free and edible dehydrated vegetables packaging film with enhanced mechanical and barrier properties from soluble soybean polysaccharide blending carboxylated nanocellulose

The aim of the study was to develop soybean polysaccharide (SSPS) -carboxylated nanocellulose (CNC) blending films with enhanced mechanical and barrier properties to be used as a tear-free and edible packaging materials. The films were formed by casting method, with CNC as the strengthening unit and glycerol as the plasticizer. The effect of CNC on structural and physical performances of the SSPS-CNC films were studied. SEM indicated that the film will stratify with excess CNC (10 %), but the film remains intact and compact. Incorporation of CNC into SSPS films did not change peak position in the XRD pattern significantly. Hydrogen bonds among SSPS, glycerol and CNC were indicated by the FTIR spectra. The compounding of CNC greatly lessened the light transmittance and hydrophilicity (CA increased from 55.42° to 70.67°), but perfected the barrier (WVP decreased from 3.595 × 10-10 to 2.593 × 10-10 g m-1 s-1 Pa-1) and mechanical properties (TS improved from 0.806 to 1.317 MPa). The results of packaging dehydrated vegetable indicated that the SSPS-8CNC film can effectively inhibit the packaged cabbage absorption water vapor. As a consequence, SSPS film perfected by CNC is hopeful to pack dehydrated vegetables in instant foods.

Development of curcumin-containing polyvinyl alcohol/chitosan active/intelligent films for preservation and monitoring of Schizothorax prenanti fillets freshness

Active/intelligent films for the preservation and monitoring of Schizothorax prenanti fillets freshness were prepared by combining curcumin (CUR) with polyvinyl alcohol/chitosan (PVA/CS) matrix. SEM images showed that the CUR with a maximum content of 1.5 % (w/w) was evenly distributed in the composite matrix. The addition of CUR did not affect the chemical structure of PVA/CS matrix, as confirmed by FTIR investigation. When 1.5 % (w/w) CUR was added, the water vapor barrier property, tensile strength and antioxidant activity of the composite film were the best, which were 5.38 ± 0.25 × 10-11 g/m·s·Pa, 62.05 ± 1.68 MPa and 85.50 ± 3.63 %, respectively. Water solubility of PVA/CS/CUR-1.5 % film was reduced by approximately 27 % compared to PVA/CS film. After adding CUR, the antibacterial properties of the composite film increased significantly. Although the addition of CUR reduced the biodegradability of PVA/CS film, the PVA/CS/CUR-1.5 % film degraded >60 % within 5 weeks. By measuring pH, weight loss, total volatile base‑nitrogen (TVB-N), thiobarbituric acid reactive substances (TBARS), and total viable counts (TVC), the preservation effect of the composite films on the fish freshness was evaluated. The fish shelf life treated by PVA/CS/CUR-1.5 % film expanded from 3-6 days to 12-15 days at 4 °C. In addition, when PVA/CS/CUR-1.5 % film was used to monitor the fish freshness, it exhibited clear color fluctuations, from yellow to orange and to red, corresponding to first-grade freshness, second-grade freshness, and rottenness of the fish, respectively. As a result, the films can be successfully used for Schizothorax prenanti fillets preservation and deterioration monitoring.

The mechanism, biopolymers and active compounds for the production of nanoparticles by anti-solvent precipitation: A review

The anti-solvent precipitation method has been investigated to produce biopolymeric nanoparticles in recent years. Biopolymeric nanoparticles have better water solubility and stability when compared with unmodified biopolymers. This review article focuses on the analysis of the state of the art available in the last ten years about the production mechanism and biopolymer type, as well as the used of these nanomaterials to encapsulate biological compounds, and the potential applications of biopolymeric nanoparticles in food sector. The revised literature revealed the importance to understand the anti-solvent precipitation mechanism since biopolymer and solvent types, as well as anti-solvent and surfactants used, can alter the biopolymeric nanoparticles properties. In general, these nanoparticles have been produced using polysaccharides and proteins as biopolymers, especially starch, chitosan and zein. Finally, it was identified that those biopolymers produced by anti-solvent precipitation were used to stabilize essential oils, plant extracts, pigments, and nutraceutical compounds, promoting their application in functional foods.

A review of curcumin in food preservation: Delivery system and photosensitization

As a natural polyphenol, curcumin has been used as an alternative to synthetic preservatives in food preservation. Different from previous reviews that mainly focus on the pH-responsive discoloration of curcumin to detect changes in food quality in real time, this paper focuses on the perspective of the delivery system and photosensitization of curcumin for food preservation. The delivery system is an effective means to overcome the challenges of curcumin like instability, hydrophobicity, and low bioavailability. Curcumin as a photosensitizer can effectively sterilize to preserve food. The practical fresh-keeping effects of the delivery system and photosensitization of curcumin on foods (fruits/vegetables, animal-derived food, and grain) were summarized comprehensively, including shelf-life extension, maintenance of physicochemical properties, nutritional quality, and sensory. Future research should focus on the development of novel curcumin-loaded materials used for food preservation, and most importantly, the biosafety and accumulation toxicity associated with these materials should be explored.

Combining Blue Light and Yellow Curcumin to Obtain a "Green" Tool for Berry Preservation against Bacterial Contamination: A Preliminary Investigation

Background: According to recent studies, tens of millions of tons of fruit are wasted each year in Europe in primary production and home/service consumption. Among fruits, berries are most critical because they have a shorter shelf life and a softer, more delicate, and often edible skin. Curcumin is a natural polyphenolic compound extracted from the spice turmeric (Curcuma longa L.) which exhibits antioxidant, photophysical, and antimicrobial properties that can be further enhanced by photodynamic inactivation of pathogens when irradiated with blue or ultraviolet light. Materials and methods: Multiple experiments were performed in which berry samples were sprayed with a complex of β-cyclodextrin containing 0.5 or 1 mg/mL of curcumin. Photodynamic inactivation was induced by irradiation with blue LED light. Antimicrobial effectiveness was assessed with microbiological assays. The expected effects of oxidation, curcumin solution deterioration, and alteration of the volatile compounds were investigated as well. Results: The treatment with photoactivated curcumin solutions reduced the bacterial load (3.1 vs. 2.5 colony forming units/mL (UFC/ml) in the control and treated groups; p-value = 0.01), without altering the fruit organoleptic and antioxidant properties. Conclusions: The explored method is a promising approach to extend berries' shelf life in an easy and green way. However, further investigations of the preservation and general properties of treated berries are still needed.

Development and Characterization of an Edible Zein/Shellac Composite Film Loaded with Curcumin

The development of functional edible films is promising for the food industry, and improving the water barrier of edible films has been a research challenge in recent years. In this study, curcumin (Cur) was added to zein (Z) and shellac (S) to prepare an edible composite film with a strong water barrier and antioxidant properties. The addition of curcumin significantly reduced the water vapor permeability (WVP), water solubility (WS), and elongation at break (EB), and it clearly improved the tensile strength (TS), water contact angle (WCA), and optical properties of the composite film. The ZS-Cur films were characterized by SEM, FT-IR, XRD, DSC, and TGA; the results indicated that hydrogen bonds were formed among the curcumin, zein, and shellac, which changed the microstructure and improved the thermal stability of the film. A test of curcumin release behavior showed controlled release of curcumin from the film matrix. ZS-Cur films displayed remarkable pH responsiveness, strong antioxidant properties, and inhibitory effects on E. coli. Therefore, the insoluble active food packaging prepared in this study provides a new strategy for the development of functional edible films and also provides a possibility for the application of edible films to extend the shelf life of fresh food.

Fish gelatin films incorporated with cinnamaldehyde and its sulfobutyl ether-β-cyclodextrin inclusion complex and their application in fish preservation

For food preservation, the packaging film needs to have higher antibacterial activity in initial phase and keep longer activity. In this study, cinnamaldehyde (CA) and its sulfobutyl ether-β-cyclodextrin inclusion complex (CA/S) were used to fabricate fish gelatin antibacterial composite films. The addition enhanced the elongation at break and light barrier property of the films. Film forming solution incorporated with CA and CA/S presented the most excellent inhibition ratio against Pseudomonas aeruginosa, which was 98.43 ± 1.11% in initial period and still 82.97 ± 4.55% at 72 h. Further, the packaging solution of gelatin combined CA and CA/S effectively inhibited the growth of microorganisms during preservation of grass carp slices. Especially, the total volatile salt-based nitrogen (TVB-N) did not exceed 10 mg/100 g at the end of storage, indicating that the active coating could obviously extend the shelf life of fish muscle. This work provided a promising food packaging system with antimicrobial and environmentally friendly.

Development and characterization of chitosan/bacterial cellulose/pullulan bilayer film with sustained release curcumin

A natural biopolymer bilayer film based on chitosan and bacterial cellulose with a protective layer of pullulan was developed by a two-step solution casting method. Curcumin was incorporated as an active antioxidant and antibacterial agent into the inner layer. The films with different curcumin concentrations were systematically characterized. Fourier transform infrared spectroscopy and X-ray diffraction analyses showed high compatibility between curcumin and the polysaccharide matrix through intermolecular interactions, which was verified by enhanced mechanical and barrier properties. The curcumin incorporation improved the thermal stability by >35.4 %, along with lower visible and ultraviolet light transmittance (< 8.6 %) and water solubility (< 25.1 %). The film had both antibacterial and antioxidant properties, and the sustained release of curcumin was largest (> 58.8 %) in the fatty food simulant lasting for over 155 h. The results suggested that the film containing 0.2 % curcumin had ideal physical and functional properties, suggesting its potential as a novel packaging material for the preservation of high-fat food.

Preparation of zein/chitosan/eugenol/curcumin active films for blueberry preservation

This study aimed to develop zein/chitosan-based films formulated with curcumin and eugenol to improve the quality of postharvest blueberries. First, the film-forming solutions were characterized (rheological property and water distribution), and the mechanical, structural properties and bioactivity of active films fabricated by casting were evaluated. Further, the active film was coated with blueberry stored at 4 °C, and physicochemical properties (weight loss, hardness, microbial counts, and appearance changes) were measured. The film-forming solutions exhibited non-Newtonian behavior. The incorporation of curcumin and eugenol improved the tensile strength and elongation at the break of films, reaching 17.86 MPa and 92.80 %, respectively. The antioxidant capacity was enhanced, and DPPH and ABTS radical scavenging rates were up to 90.60 ± 0.06 % and 86.34 ± 0.39 %, respectively. Meanwhile, the prepared active films possessed good anti-UV and sensitive pH-response color-shifting ability. Compared to the uncoated blueberry, blueberry coated with zein/chitosan/curcumin/eugenol showed lower weight loss and higher hardness, indicating that the prepared active films played a vital role in delaying the deterioration of blueberry and extending its shelf life. Overall, the zein-chitosan incorporated with curcumin and eugenol films could be a promising candidate to prolong the shelf life of food products due to their excellent bioactive capacity.

Edible films/coatings containing bioactive ingredients with micro/nano encapsulation: A comprehensive review of their fabrications, formulas, multifunctionality and applications in food packaging

Due to the consumer's pursuit of safe, nontoxic and nutritious foods, edible and/or biodegradable materials have stood out in food packaging and preservation. In this context, the preparation and application of micro/nano encapsulated active ingredients (M/N-E-BAIs) represent a step toward reinforcing the properties of sustainable and controllable food packaging, particularly for the successful incorporation of new substances and functionalities into traditional edible films/coatings. This review, from the preparation of M/N-E-BAIs, the fabrication of edible film/coating containing M/N-E-BAIs to their characterization of multifunction and the application in food, makes a systematic summary and in-depth discussion. Food-grade polymers can encapsulate bioactive ingredients (BAIs) by chemical, physicochemical and mechanical methods, thereby forming M/N-E-BAIs with suitable sustained-release and unique biological activities. Furthermore, M/N-E-BAIs is incorporated into biopolymer substrates by solvent casting, 3D printing or electrostatic spinning to obtain novel edible films/coatings. This advanced packaging material exhibits superior physicochemical and functional properties over traditional food films/coatings. Besides, their applications in foods as active and intelligent packaging can improve food quality, prolong shelf life and monitor food corruption. Even so, there are still many challenges and limitations in formulation, preparation and application of this new packaging technology that need to be addressed in the future.

Active Packaging Films Made by Complex Coacervation of Tragacanth Gum and Gelatin Loaded with Curcumin; Characterization and Antioxidant Activity

The development of biopolymer-based green packaging films has gained remarkable attention in recent years. In this study, curcumin active films were prepared using different proportions of gelatin (GE) and a soluble fraction of tragacanth gum (SFTG) (1GE:1SFTG and 2GE:1SFTG) by complex coacervation. The various ratios of used biopolymers did not significantly impact the mechanical properties, thickness, and WVP of final films. However, biopolymers' ratio impacted the moisture content, water solubility, swelling ratio, and release rate. Blending curcumin with biopolymers caused a reduction in tensile strength (from 1.74 MPa to 0.62 MPa for film containing 1GE:1SFTG and from 1.77 MPa to 0.17 MPa for film containing 2GE:1SFTG) and proliferation in elongation at break (from 81.48% to 122.00% for film containing 1GE:1SFTG and from 98.87% to 109.58% MPa for film containing 2GE:1SFTG). Moisture content and water solubility of films experienced a decrease after the addition of curcumin. Antioxidant activity of curcumin-loaded films was almost five times higher than neat film samples. Furthermore, the interreaction between the carboxylic group of SFTG and amide I of GE formed an amide linkage and was proven by FTIR analysis. TGA showed a drop in the thermal stability of film samples compared to the main ingredients. In general, the complex coacervate of SFTG and GE has the advantage of developing eco-friendly and low-cost packaging film in the food industry, especially for the protection of fatty foods.

Development of antioxidant active packaging films with slow release properties incorporated with tea polyphenols-loaded porous starch microcapsules

Slow release active packaging films can realize the sustained release of active agents and prolong the shelf life of food. For this aim, a novel slow release active polyvinyl alcohol (PVA) film was developed by using solution casting method. With porous starch loaded with tea polyphenols (PSTP) as core material and maltodextrin (MD) as wall material, PSTP@MD microcapsules were prepared using freeze drying method and used as slow release carrier of tea polyphenols (TP) in the active films. The interactions between PSTP@MD microcapsules and PVA molecular chains were physical interactions. In addition, the relative crystallinity of the slow release active films was reduced to 23.74 %. The addition of PSTP@MD microcapsules can enhance the ductility of active films and reduce the water content and swelling degree of active films by 46.74 % and 54.38 %, respectively. Moreover, the thermal stability, water vapor and ultraviolet barrier properties of active films were promoted. The transparency and antioxidant activity of active films was high, and the radical scavenging activity of active films was 58 %. The encapsulation of TP with PSTP@MD microcapsules can realize the slow release of TP. The slow release active films had antioxidant activity and sustained release properties, which could be used as an active packaging film to extend the shelf life of food.

Integrating diverse plant bioactive ingredients with cyclodextrins to fabricate functional films for food application: a critical review

The popularity of plant bioactive ingredients has become increasingly apparent in the food industry. However, these plant bioactive ingredients have many deficiencies, including low water solubility, poor stability, and unacceptable odor. Cyclodextrins (CDs), as cyclic molecules, have been extensively studied as superb vehicles of plant bioactive ingredients. These CD inclusion compounds could be added into various film matrices to fabricate bioactive food packaging materials. Therefore, in the present review, we summarized the extraction methods of plant bioactive ingredients, the addition of these CD inclusion compounds into thin-film materials, and their applications in food packaging. Furthermore, the release model and mechanism of active film materials based on various plant bioactive ingredients with CDs were highlighted. Finally, the current challenges and new opportunities based on these film materials have been discussed.

Flavor, antimicrobial activity and physical properties of gelatin film incorporated with of ginger essential oil

Adding essential oil into the gelatin-based film can enhance the antibacterial activity of the film, but excessive amounts of addition will bring the film an unpleasant flavor and reduce its mechanical performance. Hence, we prepared functional gelatin-based films by incorporating low content of ginger essential oil (GEO). The flavor of GEO was not detected from the films containing less than 1% GEO. The antimicrobial activity of films was found to be proportional to GEO content. As GEO content increased from 0 to 1%, the value of water vapor permeability (WVP) and elongation at break (EAB) increased, whereas the value of tensile strength (TS) of film decreased. The Attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy analysis revealed the vibration of gelatin film was affected by adding low content of essential oil. Surface morphologies demonstrated oil droplets and a discontinuous structure, and cross-section morphologies proved the formation of a loose structure as GEO was incorporated in the film through SEM. Sensory evaluation revealed that composite films incorporated with 0.5% GEO exhibited the best performance. The resulting films can be used as antimicrobial packaging materials with good physical properties and sensory performance.

Development of fish gelatin-chitooligosaccharide conjugates through the Maillard reaction for the encapsulation of curcumin

The poor water solubility, bioavailability and stability of bioactive compounds have become the bottleneck restricting their wide application, thus developing a functional carrier to realize the efficient encapsulation and activity improvement of active hydrophobic substances has become a research hotspot. In this work, a functional glycosylated fish gelatin (called FG-COS conjugates) carrier based on fish gelatin (FG) and chitooligosaccharide (COS) via Maillard reaction was developed. The functional carrier exhibited good antioxidant activity and high encapsulation of curcumin (Cur). Enhanced antioxidant effect of Cur loaded in FG-COS conjugates (called FG–COS–Cur nanoparticles) was achieved, showing remarkable UV protection on Cur and enhanced intracellular antioxidant activity of FG–COS–Cur nanoparticles. Remarkably, FG–COS–Cur nanoparticles increased the cell viability of H₂O₂-induced oxidative damage Caco-2 cells, drastically reduced the levels of reactive oxygen species (ROS) and lactate dehydrogenase (LDH), and significantly increased intracellular antioxidant enzyme activities, which all exhibited a dose-response relationship. These findings suggested that the FG-COS conjugates with intrinsic antioxidant activity could effectively encapsulate Cur and improved bioavailability for hydrophobic active molecules in functional food field.

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Functional carrier (FG-COS conjugates) based on glycosylation FG with COS was developed.

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FG-COS conjugates exhibited good antioxidant activity and excellent loading capacity of Cur.

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FG-COS conjugates showed remarkable UV protection on Cur.

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FG–COS–Cur nanoparticles displayed a positive effect on the antioxidant of Cur.

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FG–COS–Cur nanoparticles significantly attenuated oxidative stress damage in Caco-2 cell.

Curcumin and its uses in active and smart food packaging applications - a comprehensive review

Active and intelligent food packaging is an innovative technology to prevent food contamination and ensure food quality and safety. Active packaging protects the food from microbial contamination, while smart or intelligent packaging enables monitoring the freshness of the food or quality change in real-time. Curcumin, one of the most well-known natural colorants, has received a lot of attention for its excellent functional properties and ability to change color with changes in pH. Curcumin, the golden component of turmeric, a spice widely used in food since ancient times, is a cost-effective and abundant biomaterial with various biological properties such as antioxidant, antibacterial, antiviral, antitumor, and anti-inflammatory. Recently, active packaging or intelligent packaging systems have been actively developed using the functional properties of curcumin. In this review, we briefly reviewed curcumin's basic biological functions and discussed comprehensive and recent progress in using curcumin in various polymer-based active and smart food packaging applications.

Novel active starch films incorporating tea polyphenols-loaded porous starch as food packaging materials

A novel active food packaging film was developed by casting a corn starch/tea polyphenol (TP)-loaded porous starch (PS, obtained by enzymatic hydrolysis) film forming solution, with the latter helping to regulate the slow release of TP. Results showed that PS had a favorable TP adsorption capacity, and the casted films had a homogeneous distribution of the formulation components. Likewise, the active films had good mechanical properties, UV barrier properties, thermal stability, and excellent antioxidant properties. The slow release of TP from the films was sustained, which is a desired characteristic for extending the protection afforded by the active film to the food under consideration.

Release of Cinnamaldehyde and Thymol from PLA/Tilapia Fish Gelatin-Sodium Alginate Bilayer Films to Liquid and Solid Food Simulants, and Japanese Sea Bass: A Comparative Study

This study aimed to develop an active biodegradable bilayer film and to investigate the release behaviors of active compounds into different food matrices. Cinnamaldehyde (CI) or thymol (Ty) was encapsulated in β-cyclodextrin (β-CD) to prepare the active β-CD inclusion complex (β-CD-CI/β-CD-Ty). The tilapia fish gelatin-sodium alginate composite (FGSA) containing β-CD-CI or β-CD-Ty was coated on the surface of PLA film to obtain the active bilayer film. Different food simulants including liquid food simulants (water, 3% acetic acid, 10% ethanol, and 95% ethanol), solid dry food simulant (modified polyphenylene oxide (Tenax TA)), and the real food (Japanese sea bass) were selected to investigate the release behaviors of bilayer films into different food matrixes. The results showed that the prepared β-CD inclusion complexes distributed evenly in the cross-linking structure of FGSA and improved the thickness and water contact angle of the bilayer films. Active compounds possessed the lowest release rates in Tenax TA, compared to the release to liquid simulants and sea bass. CI and Ty sustained the release to the sea bass matrix with a similar behavior to the release to 95% ethanol. The bilayer film containing β-CD-Ty exhibited stronger active antibacterial and antioxidant activities, probably due to the higher release efficiency of Ty in test mediums.

Preparation and Characterization of Chitosan Films Containing Lychee (Litchi chinensis Sonn.) Pericarp Powder and Their Application as Active Food Packaging

In this study, lychee (Litchi chinensis Sonn.) pericarp powder was added to chitosan (CHS) matrix to develop active packaging films, and their structure, physicochemical, antibacterial, antioxidant, and functional properties were investigated. FT-IR results showed that intermolecular hydrogen bonds were formed between CHS and polyphenols in lychee pericarp powder (LPP), and the intermolecular interaction interfered with the assembly of CHS into semi-crystal structure, which reduced the crystallinity of CHS film. Incorporation of LPP significantly reduced water vapor permeability, water solubility, swelling degree, and elongation at break of CHS film (p < 0.05). However, UV-visible light barrier, tensile strength, and antibacterial and antioxidant properties of CHS films were increased by LPP incorporation. CHS-LPP film remarkably lowered the weight loss, firmness, titratable acidity, and total soluble solids of fresh-cut apple after five days storage. CHS-LPP film packaging effectively inhibited the browning of fresh-cut apple and the reduction of polyphenol content in apple juice caused by polyphenol oxidase (PPO)-mediated oxidation during storage. Therefore, CHS-LPP films have great potential as food packaging material to ensure the quality and extend the shelf life of food products.

Native Cyclodextrins and Their Derivatives as Potential Additives for Food Packaging: A Review

Cyclodextrins (CDs) have been used by the pharmaceutical and food industries since the 1970s. Their cavities allow the accommodation of several hydrophobic molecules, leading to the formation of inclusion complexes (ICs) increasing the guest molecules’ stability, allowing their controlled release, enhancing their water solubility and biodisponibility. Due to these, CDs and their ICs have been proposed to be used as potential allies in food packaging, especially in active packaging. In this review, we present the many ways in which the CDs can be applied in food packaging, being incorporated into the polymer matrix or as a constituent of sachets and/or pads aiming for food preservation, as well as the diverse polymer matrices investigated. The different types of CDs, natives and derivatives, and the several types of compounds that can be used as guest molecules are also discussed.

Characterization and antioxidant properties of chitosan film incorporated with modified silica nanoparticles as an active food packaging

In this study, two modified silica nanoparticles (SiO₂-GA NPs) were successfully obtained by covalently grafting gallic acid onto silica nanoparticles. The mean particle diameters of their were 112.7 ± 0.55 nm (1-SiO₂-GA NPs) and 408.7 ± 3.20 nm (4-SiO₂-GA NPs), respectively. Novel antioxidant active packaging composite films were prepared by incorporation of 1-SiO₂-GA NPs or 4-SiO₂-GA NPs into chitosan. The structure analysis of the composite films showed that intermolecular hydrogen bonds were formed between the two modified silica nanoparticles and chitosan. Compared with the chitosan film, the mechanical properties, water vapor barrier property and UV light barrier ability of the composite films were significantly improved. Moreover, the incorporated of the two modified silica nanoparticles significantly increased antioxidant activity of the composite films. This study indicates that composite films incorporated with modified silica nanoparticles, especially the incorporation of 1-SiO₂-GA NPs can be used as novel antioxidant food packaging composite films.

Cellulose Nanocrystals Reinforced Zein/Catechin/β-Cyclodextrin Inclusion Complex Nanoparticles Nanocomposite Film for Active Food Packaging

In this study, following the green, environmentally friendly and sustainable development strategy, cellulose nanocrystals (CNCs) were prepared through a solvent-free esterification reaction between microcrystalline cellulose and maleic anhydride, combined with subsequent ultrasonic treatment, and maleic-anhydride-modified CNC-reinforced zein/catechin/β-cyclodextrin inclusion complex nanoparticles nanocomposite films were prepared by a facile solution casting. The amount of CNCs in the film matrix was 0–8 wt%, and their effect on structural, physicochemical and functional properties of the resulting films were investigated. SEM images showed that the addition of CNCs made the microstructure of the film more smooth and uniform. The intermolecular hydrogen bonds between CNCs and film matrix were supported by FT-IR. XRD analysis also confirmed the appearance of a crystalline peak due to the existence of CNCs inside the films. The incorporation of CNCs significantly reduced water vapor permeability, water solubility and the swelling degree of the nanocomposite film, and also significantly increased tensile strength and elongation at break from 12.66 to 37.82 MPa and 4.5% to 5.2% (p < 0.05). Moreover, nanocomposite film packaging with CNCs can effectively inhibit the oxidation of soybean oil.

Development and characterization of zein edible films incorporated with catechin/β-cyclodextrin inclusion complex nanoparticles

Zein films incorporated with catechin/β-cyclodextrin inclusion complex nanoparticles (CINPs) were developed, and the structure, physicochemical, antioxidant and release properties of the films were characterized. FT-IR results indicated that intermolecular hydrogen bonds were formed between the CINPs and zein. XRD analysis showed that the addition of CINPs did not change the crystal structure of zein film. SEM images observed that the addition of NPs made zein film surface more smooth and dense. Since the nanoparticles occupy the pores of the film matrix, the swelling degree and water vapor barrier property were improved. CINPs addition significantly increased tensile strength, from 2.28 to 12.49 MPa, and increased elongation at break, from 1.52 % to 4.5 % (p < 0.05). The nanocomposite film still maintains strong antioxidant activity after storage. The release behavior of catechin from zein film was controlled. Therefore, zein composites can be used as a potential antioxidant food packaging film-forming material.

Cyclodextrin Monomers and Polymers for Drug Activity Enhancement

Cyclodextrins (CDs) and cyclodextrin (CD)-based polymers are well-known complexing agents. One of their distinctive features is to increase the quantity of a drug in a solution or improve its delivery. However, in certain instances, the activity of the solutions is increased not only due to the increase of the drug dose but also due to the drug complexation. Based on numerous studies reviewed, the drug appeared more active in a complex form. This review aims to summarize the performance of CDs and CD-based polymers as activity enhancers. Accordingly, the review is divided into two parts, i.e., the effect of CDs as active drugs and as enhancers in antimicrobials, antivirals, cardiovascular diseases, cancer, neuroprotective agents, and antioxidants.

Development of active packaging films based on chitosan and nano-encapsulated luteolin

Luteolin is a flavone with potent antioxidant and antimicrobial activities. In this study, luteolin was encapsulated in oil-in-water nanoemulsions that were emulsified by glycerol monooleate and Tween 20. Results showed 68 mg luteolin-loaded nanoemulsions had the highest stability (zeta potential of -39.8 mV) and encapsulation efficiency (89.52%). Then, active packaging films were developed by incorporating free or nano-encapsulated luteolin into chitosan-based matrix. The microstructure, physical and functional properties of CS film containing free luteolin (CS-LL) or nano-encapsulated luteolin (CS-LLNEs) were compared. Different from CS film, CS-LL and CS-LLNEs films had compact inner microstructure and strengthened intermolecular interactions. Moreover, CS-LLNEs film was more homogenous and compact than CS-LL film. As a result, CS-LLNEs film presented higher water vapor and oxygen barrier abilities and mechanical properties in comparison with CS-LL film. In addition, CS-LLNEs film showed slower release rate of luteolin in 95% ethanol (fatty food stimulant) as compared with CS-LL film. The controlled release of luteolin from film matrix could guarantee CS-LLNEs film to exert antioxidant activity up to 10 days. Our results suggest CS-LLNEs film can be developed as an emerging active packaging material that has potential applications in food industry.

Progresses in Food Packaging, Food Quality, and Safety-Controlled-Release Antioxidant and/or Antimicrobial Packaging

Food packaging is designed to protect foods, to provide required information about the food, and to make food handling convenient for distribution to consumers. Packaging has a crucial role in the process of food quality, safety, and shelf-life extension. Possible interactions between food and packaging are important in what is concerning food quality and safety. This review tries to offer a picture of the most important types of active packaging emphasizing the controlled/target release antimicrobial and/or antioxidant packaging including system design, different methods of polymer matrix modification, and processing. The testing methods for the appreciation of the performance of active food packaging, as well as mechanisms and kinetics implied in active compounds release, are summarized. During the last years, many fast advancements in packaging technology appeared, including intelligent or smart packaging (IOSP), (i.e., time-temperature indicators (TTIs), gas indicators, radiofrequency identification (RFID), and others). Legislation is also discussed.

Smart edible films based on mucilage of lallemantia iberica seed incorporated with curcumin for freshness monitoring

The objective of the present work was first to develop a smart packaging system based on Lallemantia iberica seed gum (LISG)/curcumin and, subsequently, investigate its physicochemical characteristics and biological activity. Finally, the response of LISG/curcumin films against pH change and the spoilage of shrimp were tested. The barrier properties and mechanical performance of the films improved as the curcumin concentration increased. FT-IR analysis revealed the formation of physical interaction between LISG and curcumin. LISG/curcumin films showed a continuous and steady release of curcumin. The incorporation of curcumin into LISG matrix imparts antioxidant and antibacterial/mold activity to the films. A strong positive correlation was observed between total volatile base nitrogen (TVBN) content of shrimp and a* (redness) during storage time (Pearson correlation = 0.975). Eventually, LISG/curcumin film could be a promising smart packaging system capable of detecting food spoilage.

Effects of Emulsifier Type and Post-Treatment on Stability, Curcumin Protection, and Sterilization Ability of Nanoemulsions

Curcumin has a high inhibitory effect on many potential diseases caused by bacteria and fungi. However, its degradability and low water solubility limit its application. Loading curcumin with an emulsion delivery system can overcome these problems. Five different types of emulsifiers were used to prepare the curcumin-loaded nanoemulsions, namely, Tween 80 (T80), Span 80 (S80), sodium dodecyl sulfate (SDS), soybean protein isolate (SPI), and lecithin (LEC). The effects of emulsifier types and post-treatment methods on emulsion stability and curcumin-load efficiency were studied. In addition, photodynamic inactivation was used to test the antibacterial effect of nanoemulsions on Escherichia coli under blue light excitation. The five types of emulsifiers could form uniform emulsions with good storage stability and with antibacterial capacity on Escherichia coli. Among them, the T80 and LEC emulsions had good stability, coating effect, and sterilization performance under heating or room temperature. Both curcumin-loaded bactericidal emulsions had the potential for large-scale applications. A nanoemulsions delivery system could effectively improve the dispersion and chemical stability of curcumin in water. An emulsion loaded with antibacterial photosensitizer represents a new idea for the storage and preservation of food commodities.

Conversional fluorescent kiwi peel phenolic extracts: Sensing of Hg2+ and Cu2+, imaging of HeLa cells and their antioxidant activity

The valorization, resource generation and the functional characteristic exploration of domestic waste still face enormous challenges. Kiwi peels, a common kind of fruit waste, contain a large amount of phenolic substances, including polyphenols, flavonoids, etc., which can be explored and reused in food and biomedical fields. By ultrasonic assisted extraction technology, we obtained conversional fluorescence kiwi peel phenolic extracts (PE) which possessed gradient magenta fluorescence relying on the content of ethanol in the solution, as well as strong antioxidant activity. Besides, metal ions sensing assay revealed that PE can specifically sense Hg²⁺ and Cu²⁺ (LOD: 1.16 and 0.17 μM, respectively) accompanied with a fluorescence conversion from magenta fluorescence to blue. Moreover, employing the prepared PE as fluorescent probes, imaging of HeLa cells can be easily achieved with satisfactory resolution. Additionally, PE was incorporated into the gelatin matrix, successfully fabricating a green, edible degradable film with excellent antioxidant activity.