Encapsulation of gallic acid/cyclodextrin inclusion complex in electrospun polylactic acid nanofibers: Release behavior and antioxidant activity of gallic acid

Effect of different solvents on bioactive phenolics and antioxidant, antimicrobial, and α-glucosidase inhibition activities of Barringtonia acutangula Gaertn. flower extracts

Barringtonia acutangula Gaertn. is a well-known vegetable and medicinal plant. This study assessed solvents' effect on phytochemical contents and bioactivities of flower extracts. High-polar extracts (ethanol, aqueous) demonstrated much higher phenolic contents (132.21, 240.83 mg gallic acid equivalent per gram of extract, respectively) than non-/medium-polar extracts, with more impressive flavonoid/saponin contents. Aqueous extract was highlighted for antioxidant activity and α-glucosidase inhibition (IC50 = 35.01, 5.63 μg/mL, respectively) on which HPLC analysis revealed gallic acid (1), pyrogallol (2), ilexsaponin A1 (3) as major compounds for 1.83, 1.26, 0.15%, respectively. Phenolics 1 and 2 displayed strong α-glucosidase inhibition (IC50 6.6 - 18.7 μM), consolidated by molecular docking studies and molecular dynamics simulations, based on their stable complexes with α-glucosidase protein (MAL32) via H-bonds of hydroxy phenol moieties, which was more effective in 2. The study suggested the potency of B. acutangula flower water extract and its phenolics, displaying the need for in-depth investigation.

Advanced flame-retardant biocomposites: Polylactic acid reinforced with green gallic acid‑iron‑phosphorus coated flax fibers

This study introduces a sustainable approach for enhancing the fire retardancy and smoke suppression of poly(lactic acid) (PLA) composites, contributing to addressing one of the major challenges in biocomposites that limits their application in various engineering fields, as automotive and construction sectors. Flax fibers (FF) were surface functionalized with a novel organic-inorganic hybrid flame retardant (FR), offering a sustainable bioinspired approach that mitigates potential mechanical properties impairment and FR leaching, which can cause environmental concerns and reduced composite durability. The process involves a three-step coating procedure. First, the flax fibers (FF) are pretreated with ozone to promote carboxylic group formation (FF-O3); subsequently, gallic acid (GA) units are covalently immobilized on the fiber surface (FF-GA); finally, the hybrid FR iron phenylphosphonate is complexed with the phenolic groups of GA units (FF-GA-FeP). Fourier transform infrared (FT-IR) analysis of FF-GA-FeP confirmed the presence of specific absorptions associated with the deposited FR coating. Scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDS) revealed changes in fiber morphology and confirmed the incorporation of iron and phosphorus. Solid-state nuclear magnetic resonance (SSNMR) spectroscopy and X-ray WAXS microscopy revealed that fibers' crystallinity was not significantly affected by derivatization. Microwave plasma atomic emission spectroscopy (MP-AES) detected a precise 0.1 wt% iron loading. Using FF-GA-FeP as reinforcement in PLA-based composites (PLA/FF-FeP) resulted in enhanced thermal stability and flame retardancy of the composites, with minimal coating application, as revealed by thermogravimetric analysis (TGA) and cone calorimetry tests (CCT). A decrease in peak of heat release rate (pHRR), total smoke release (TSR), specific extinction area (SEA), and Fire Propagating Index (FPI) of 5, 87, 68, and 9.5 %, respectively, was achieved for PLA/FF-FeP, compared to untreated flax fiber reinforced PLA (PLA/FF). Furthermore, preliminary tensile tests indicate minor changes in tensile strength and a slight increase in stiffness of the PLA/FF-FeP compared to PLA/FF. Hence, in the biocomposite, the immobilization of a minimal amount of iron phenylphosphonate directly on the flax fiber surface proved to be an effective strategy for smoke suppression while preserving the mechanical integrity of the composite.

Protecting anthocyanins of postharvest blueberries through konjac glucomannan/low-acyl gellan gum coatings contained thymol microcapsule during low-temperature storage

In order to protect the anthocyanins in blueberries during low-temperature storage, TMs/KGM/LAG (TKL) coatings were developed by composite thymol/β-cyclodextrin (β-CD) microcapsules (TMs), konjac glucomannan (KGM), and low acyl gellan gum (LAG). The results showed that the TMs prolonged the release of thymol for at least 30 d. The TKL was effective in maintaining the color of blueberry skin by regulating the activities of key enzymes for anthocyanin synthesis and degradation. Among the different treatment groups, TKL60 (thymol concentration of 60 mg/L) was the most effective in protecting anthocyanin. At 42 d of storage, the TKL60 group showed the highest anthocyanin levels of malvidin-3-O-galactoside (718.38 μg/g), delphinidin-3-O-galactoside (343.75 μg/g) and cyanidin-3-O-galactoside (40.67 μg/g). In addition, TKL60 treatment still showed good maintain the qualities of blueberries (weight loss, decay, hardness and TSS). Thus, this study provides a new approach to protect anthocyanin in blueberries after harvest during low-temperature storage.

Bacterial nanocellulose-based nanopaper activated by β-cyclodextrin/ Salvia officinalis essential oil complexes for shelf life extension of shrimp

Active bacterial nanocellulose (BNC) nanopapers containing Salvia officinalis essential oil (SEO) in free form and encapsulated with β-cyclodextrin (βCD) were prepared, and their effect on the shelf life extension of shrimp was investigated. The GC-MS analysis of the SEO indicated the presence of various active compounds such as Thujone (21.53 %), Ledol (12.51 %) and Eucalyptol (11.28 %) in the essential oil composition. The cytotoxicity of the SEO and SEO-βCD complexes in the L929 cell line was quite low. FTIR analysis revealed new interactions in the nanopapers containing SEO-βCD complexes. Microscopic images showed that SEO-βCD complexation improved the surface morphology of the BNC nanopapers, whereas free SEO had a negative effect. X-ray diffraction patterns of the nanopapers showed higher crystallinity of the SEO-βCD containing nanopapers than that of the SEO-incorporated nanopapers. Moreover, the addition of the SEO-βCD complex improved the thermal properties of the BNC nanopaper. Water contact angle analysis showed higher hydrophobicity of the samples containing free SEO than that of the other samples. Both SEO-βCD and free SEO increased the elongation at break and decreased the tensile strength of the nanopaper. The prepared active films showed a greater antimicrobial effect on L. monocytogenes than on E. coli. The results showed a higher antioxidant capacity of the free SEO-containing nanopapers (58-78 %). The desirable effects of the active nanopapers on shrimp preservation were demonstrated by the results obtained for the microbial load, pH, and volatile nitrogen content of the product. The results demonstrate the potential of the prepared BNC active nanopapers for use in active antioxidant/antimicrobial food packaging.

Novel Hydrogel Adjuvant of Chinese Medicine External Preparations for Accelerated Healing of Deep Soft Tissue Injuries

Traditional Chinese medicine external prescriptions have displayed excellent clinical effects for treating deep soft tissue injuries. However, the effects cannot be fully utilized due to the limitations of their dosage forms and usage methods. It is still a challenge to develop a satisfactory adjuvant of traditional Chinese medicine external prescriptions. Herein, a hydrogel adjuvant was prepared based on gallic acid coupled ε-poly-l-lysine and partially oxidized hyaluronic acid. The resulting adjuvant shows great physicochemical properties, low hemolysis rate (still much less than 5% at 5 mg/mL), excellent antibacterial ability (about 95% at 2 mg/mL), strong antioxidant ability (1.687 ± 0.085 mmol FeSO4/(g hydrogel) at 1 mg/mL), as well as outstanding biocompatibility. A clinically used Chinese medicine external preparation was selected as an example to investigate the effectiveness of the adjuvant in treating deep soft tissue injuries. The results show that the prescription can be evenly dispersed in the adjuvant. Moreover, the introduction of the prescription has not significantly changed these advanced properties of the adjuvant. Importantly, the hydrogel adjuvant significantly improves the effectiveness of the prescription in treating deep soft tissue injuries. This work offers an alternative approach to the development of a new-type adjuvant of Chinese medicine external preparations and also provides a new strategy for the combination of traditional Chinese medicine and hydrogel to treat clinical diseases.

A review on bio-based polymer polylactic acid potential on sustainable food packaging

Poly(lactic acid) (PLA) stands as a compelling alternative to conventional plastic-based packaging, signifying a notable shift toward sustainable material utilization. This comprehensive analysis illuminates the manifold applications of PLA composites within the realm of the food industry, emphasizing its pivotal role in food packaging and preservation. Noteworthy attributes of PLA composites with phenolic active compounds (phenolic acid and aldehyde, terpenes, carotenoid, and so on) include robust antimicrobial and antioxidant properties, significantly enhancing its capability to bolster adherence to stringent food safety standards. The incorporation of microbial and synthetic biopolymers, polysaccharides, oligosaccharides, oils, proteins and peptides to PLA in packaging solutions arises from its inherent non-toxicity and outstanding mechanical as well as thermal resilience. Functioning as a proficient film producer, PLA constructs an ideal preservation environment by merging optical and permeability traits. Esteemed as a pioneer in environmentally mindful packaging, PLA diminishes ecological footprints owing to its innate biodegradability. Primarily, the adoption of PLA extends the shelf life of products and encourages an eco-centric approach, marking a significant stride toward the food industry's embrace of sustainable packaging methodologies.

Graphical abstract

Facile and Bioinspired Approach from Gallic Acid for the Synthesis of Biobased Flame Retardant Coatings of Basalt Fibers

A sustainable, bioinspired approach to functionalize basalt fibers with an innovative gallic acid (GA)-iron phenyl phosphonate complex (BF-GA-FeP), for the purpose of improving the flame retardancy in composite materials, is developed. BFs were at first pretreated with O3, obtaining surface free hydroxyl groups that allowed the subsequent covalent immobilization of biosourced GA units on the fiber through ester linkages. Phenolic -OH groups of the GA units were then exploited for the complexation of iron phenyl phosphonate, resulting in the target-complex-coated BF fiber (BF-GA-FeP). Microwave plasma atomic emission spectroscopy and scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy analyses of BF-GA-FeP highlighted an increase in iron content, modification of fiber morphology, and occurrence of phosphorus, respectively. BFs, modified with a low amount of the developed complex, were used to reinforce a poly(lactic acid) (PLA) matrix in the production of a biocomposite (PLA/BF-FeP). PLA/BF-FeP showed a higher thermal stability than neat PLA and PLA reinforced with untreated BFs (PLA/BF), as confirmed by thermogravimetric analysis. The cone calorimeter test highlighted several advantages for PLA/BF-FeP, including a prolonged time to ignition, a reduced time to flame out, an 8% decrease in the peak heat release rate, and a 15% reduced fire propagating index compared to PLA/BF.

Transmucosal Delivery of Peptides and Proteins Through Nanofibers: Current Status and Emerging Developments

Advancements in recombinant DNA technology have made proteins and peptides available for diagnostic and therapeutic applications, but their effectiveness when taken orally leads to poor patient compliance, requiring clinical administration. Among the alternative routes, transmucosal delivery has the advantage of being noninvasive and bypassing hepato-gastrointestinal clearance. Various mucosal routes-buccal, nasal, pulmonary, rectal, and vaginal-have been explored for delivering these macromolecules. Nanofibers, due to their unique properties like high surface-area-to-volume ratio, mechanical strength, and improved encapsulation efficiency, serve as promising carriers for proteins and peptides. These nanofibers can be tailored for quick dissolution, controlled release, enhanced encapsulation, targeted delivery, and improved bioavailability, offering superior pharmaceutical and pharmacokinetic performance compared to conventional methods. This leads to reduced dosages, fewer side effects, and enhanced patient compliance. Hence, nanofibers hold tremendous potential for protein/peptide delivery, especially through mucosal routes. This review focuses on the therapeutic application of proteins and peptides, challenges faced in their conventional delivery, techniques for fabricating different types of nanofibers and, various nanofiber-based dosage forms, and factors influencing nanofiber generation. Insights pertaining to the precise selection of materials used for fabricating nanofibers and regulatory aspects have been covered. Case studies wherein the use of specific protein/peptide-loaded nanofibers and delivered via oral/vaginal/nasal mucosa for diagnostic/therapeutic use and related preclinical and clinical studies conducted have been included in this review.

Dietary gallic acid as an antioxidant: A review of its food industry applications, health benefits, bioavailability, nano-delivery systems, and drug interactions

Gallic acid (GA), a dietary phenolic acid with potent antioxidant activity, is widely distributed in edible plants. GA has been applied in the food industry as an antimicrobial agent, food fresh-keeping agent, oil stabilizer, active food wrap material, and food processing stabilizer. GA is a potential dietary supplement due to its health benefits on various functional disorders associated with oxidative stress, including renal, neurological, hepatic, pulmonary, reproductive, and cardiovascular diseases. GA is rapidly absorbed and metabolized after oral administration, resulting in low bioavailability, which is susceptible to various factors, such as intestinal microbiota, transporters, and metabolism of galloyl derivatives. GA exhibits a tendency to distribute primarily to the kidney, liver, heart, and brain. A total of 37 metabolites of GA has been identified, and decarboxylation and dihydroxylation in phase I metabolism and sulfation, glucuronidation, and methylation in phase Ⅱ metabolism are considered the main in vivo biotransformation pathways of GA. Different types of nanocarriers, such as polymeric nanoparticles, dendrimers, and nanodots, have been successfully developed to enhance the health-promoting function of GA by increasing bioavailability. GA may induce drug interactions with conventional drugs, such as hydroxyurea, linagliptin, and diltiazem, due to its inhibitory effects on metabolic enzymes, including cytochrome P450 3A4 and 2D6, and transporters, including P-glycoprotein, breast cancer resistance protein, and organic anion-transporting polypeptide 1B3. In conclusion, in-depth studies of GA on food industry applications, health benefits, bioavailability, nano-delivery systems, and drug interactions have laid the foundation for its comprehensive application as a food additive and dietary supplement.

Effects of alkaline pH and gallic acid enrichment on the physicochemical properties of sesame protein and common vetch starch-based composite films

In this study, sesame (Sesamum indicum L.) meal protein and common vetch (Vicia sativa L.) starch were extracted and used to obtain biodegradable composite films at different pH values (7, 9, and 11). Films were plasticized with glycerol (2.5 %) and enriched with gallic acid (0.25 %). Increasing pH promoted mechanical properties of the films with the developed barrier and thermal characteristics. Gallic acid addition at pH 7 resulted in lower tensile strength and higher elongation by reducing intermolecular forces, and a shift of diffraction peaks through lower angles due to crystal lattice expansion, as compared to neutral films without gallic acid. On the other hand, gallic acid-enriched films at neutral pH exhibited superior antioxidant properties. The mild alkalinity with gallic acid provided the lowest water vapor permeability, high thermal stability, improved mechanical properties and light barrier property due to deprotonation and subsequent interactions with biopolymers. The FTIR spectrum confirmed intense interactions, such as crosslinking and covalent bonding, promoted by mild alkalinity. Therefore, sesame protein and common vetch starch-based composite film with gallic acid incorporation at pH 9 can be recommended to be used in biodegradable active food packaging applications.

Enhancing hamburger shelf life and quality using gallic acid encapsulated in gelatin/tragacanth gum complex coacervate

Considering mitigating oxidative degradation and inhibiting microbial proliferation in meat products, incorporating antioxidant and antimicrobial materials is critical to enhance shelf life, maintain quality, and ensure food safety. So, this study aimed to investigate the antimicrobial and antioxidant effects of encapsulated gallic acid on the quality of hamburgers during 30 days of storage. Gallic acid was microencapsulated in tragacanth gum/gelatin complex coacervate, and its encapsulation efficiency was optimized by the response surface method. The optimized encapsulation conditions were 1:4 polymer ratio (tragacanth to gelatin ratio); total polymer content, 0.9 %; pH, 3.5; and gallic acid content, 0.88 %, resulting in a 98 % encapsulation efficiency. The microcapsules were characterized using various techniques, including scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, and differential scanning calorimetry. 400 ppm encapsulated gallic acid was added to the hamburger formulation, and various microbial properties, chemical analysis (peroxide value (POV) and thiobarbituric acid (TBA)), and sensory properties of the hamburgers were evaluated during storage. Results showed that gallic acid in the hamburgers decreased lipid oxidation from 0.126 to 0.103 mg MAD/kg in the TBA test and 12.73 to 11.03 meq/kg in the POV test during one month of storage. Also, phenolic compounds could prevent the growth and proliferation of spoilage microorganisms by damaging the microorganism cell walls and changing the metabolic processes. So, the amounts of total count and yeast and mold in the treated sample were lower than in the control sample. Significantly, adding encapsulated gallic acid did not negatively affect the flavor or overall evaluation of the samples. Overall, these findings suggested that encapsulated gallic acid is a suitable candidate to maintain chemical, microbial, and sensory characteristics of hamburgers over time.

Ultrasonically functionalized chitosan-gallic acid films inactivate Staphylococcus aureus through envelope-disruption under UVA light exposure

The significant threat of foodborne pathogens contamination has continuously promoted the development of efficient antimicrobial food packaging materials. Here, an antimicrobial film was prepared with gallic acid-grafted-chitosan (CS/GA) that obtained by a two-step ultrasound method. The resultant films exhibited good transparency, improved UV barrier performance, and enhanced mechanical strength. Specifically, with the grafting of 1.2 % GA, the UV blocking ability of CS/GA film at 400 nm was significantly increased by 19.7 % and the tensile strength was nearly two times higher than that of CS film. Moreover, the CS/GA films exhibited an inspiring photoactivated bactericidal ability under 400 nm UVA light irradiation that eradicated almost 99.9 % of Staphylococcus aureus (S. aureus) cells within 60 min. To gain more insights into the antibacterial mechanism, the treated S. aureus cells were further investigated by visualizing bacterial ultrastructure and analyzing membrane properties. The results pointed to the peptidoglycan layer as the primary action target when bacteria come into contact with CS/GA films. Afterward, the intracellular oxidative lesions, disrupted bacterial integrity, and disordered membrane functional properties collectively resulted in eventual cell death. The findings revealed the unique peptidoglycan targeting and membrane disruptive mechanisms of CS/GA films, confirming the application values in controlling foodborne pathogens.

Antibacterial aroma compounds as property modifiers for electrospun biopolymer nanofibers of proteins and polysaccharides: A review

Electrospinning is one of the most promising techniques for producing biopolymer nanofibers for various applications. Proteins and polysaccharides, among other biopolymers, are attractive substrates for electrospinning due to their favorable biocompatibility and biodegradability. However, there are still challenges to improve the mechanical properties, water sensitivity and biological activity of biopolymer nanofibers. Therefore, these strategies such as polymer blending, application of cross-linking agents, the addition of nanoparticles and bioactive components, and modification of biopolymer have been developed to enhance the properties of biopolymer nanofibers. Among them, antibacterial aroma compounds (AACs) from essential oils are widely used as bioactive components and property modifiers in various biopolymer nanofibers to enhance the functionality, hydrophobicity, thermal properties, and mechanical properties of nanofibers, which depends on the electrospun strategy of AACs. This review summarizes the recently reported antimicrobial activities and applications of AACs, and compares the effects of four electrospinning strategies for encapsulating AACs on the properties and applications of nanofibers. The authors focus on the correlation of the main characteristics of these biopolymer electrospun nanofibers with the encapsulation strategy of AACs in the nanofibers. Moreover, this review also particularly emphasizes the impact of the characteristics of these nanofibers on their application field of antimicrobial materials.

High-speed electrospinning of phycocyanin and probiotics complex nanofibrous with higher probiotic activity and antioxidation

This study reports for the first time the co-encapsulation of probiotics and phycocyanin by electrospinning. SEM showed that the electrospun fibers exhibited a homogeneous, smooth surface and a circular shape. XRD and ATR-FTIR results showed that Lactiplantibacillus plantarum 1-24-LJ and Pc were co-embedded in the fibers and that the presence of L. plantarum 1-24-LJ promoted the encapsulation of phycocyanin. TG analysis showed that the addition of phycocyanin and L. plantarum 1-24-LJ improved the composite fiber's thermal stability. The fibers co-embedded with phycocyanin and L. plantarum 1-24-LJ had the highest DPPH and ABTS⁺ activity, indicating that the two may have synergistic antioxidant effects. After 28 days, the viability of the strain could still be above 6 log cfu/g, and the addition of phycocyanin could help to improve the strain's survivability. In this experiment, a co-embedding method for probiotics and antioxidants was proposed, which could effectively increase the survivability of probiotics and improve the antioxidant properties of the fibers.

Starch, gallic acid, their inclusion complex and their effects in diabetes and other diseases-A review

Starch is the most important energy-providing component of food. It is useful for maintaining the structural and rheological consistency of food, ad thus, in turn, is responsible for maintaining the freshness of food. Polyphenols are present in plant products in huge amounts as secondary metabolites. Gallic acid, one of the potent plant polyphenols, has been reported to have excellent anti-inflammatory, antioxidative, anticarcinogenic, microbicidal, and antidiabetic properties. Till date, very few articles on the starch-polyphenol inclusion complex are present. Quite a few hypotheses have been proposed as to how the formation of an inclusion complex of starch with polyphenol can slower the digestion or the hydrolysis of starch. The efficient qualities of starch-polyphenol systems, such as reduced starch digestion, lower blood glucose and preserving food freshness, have formed a necessity for investigation in this area. The focus of this review centers on the recent research on starch-polyphenol interactions and starch-gallic acid inclusion complexes in native and extruded food systems, as well as how the production of these complexes can aid in the treatment of diseases, particularly diabetes mellitus.

Sinapic Acid Co-Amorphous Systems with Amino Acids for Improved Solubility and Antioxidant Activity

The objective of this study was to obtain co-amorphous systems of poorly soluble sinapic acid using amino acids as co-formers. In order to assess the probability of the interaction of amino acids, namely, arginine, histidine, lysine, tryptophan, and proline, selected as co-formers in the amorphization of sinapic acid, in silico studies were carried out. Sinapic acid systems with amino acids in a molar ratio of 1:1 and 1:2 were obtained using ball milling, solvent evaporation, and freeze drying techniques. X-ray powder diffraction results confirmed the loss of crystallinity of sinapic acid and lysine, regardless of the amorphization technique used, while remaining co-formers produced mixed results. Fourier-transform infrared spectroscopy analyses revealed that the co-amorphous sinapic acid systems were stabilized through the creation of intermolecular interactions, particularly hydrogen bonds, and the potential formation of salt. Lysine was selected as the most appropriate co-former to obtain co-amorphous systems of sinapic acid, which inhibited the recrystallization of sinapic acid for a period of six weeks in 30 °C and 50 °C. Obtained co-amorphous systems demonstrated an enhancement in dissolution rate over pure sinapic acid. A solubility study revealed a 12.9-fold improvement in sinapic acid solubility after introducing it into the co-amorphous systems. Moreover, a 2.2-fold and 1.3-fold improvement in antioxidant activity of sinapic acid was observed with respect to the ability to neutralize the 2,2-diphenyl-1-picrylhydrazyl radical and to reduce copper ions, respectively.

Supramolecular assembly of benzocaine bearing cyclodextrin cavity via host-guest complexes on polyacrylonitrile as an electrospun nanofiber

Nanofibers (NFs) can be encapsulated with cyclodextrins (CDs) based host-guest complexes (HCs) in order to enable many biological applications. Here, benzocaine (BNZ) forms HCs with β-cyclodextrin (β-CD) that are co-precipitated and further added to polyacrylonitrile (PAN) solution for making BNZ:β-CD-HCs/PAN NFs material with the aid of electrospinning technique. The marginal increase in absorbance and fluorescence intensity along with the shift in spectral maxima of BNZ in the presence of β-CD suggested the host-guest interaction between BNZ and β-CD. NFs showed a uniform and clean morphology in SEM images and interestingly, the ICs revealed that significantly thinner in terms of average fiber diameter (AFD) than those of free BNZ on PAN medium. BNZ molecule is completely included in the PAN surface as the result of NFs and thus, the original sharp peaks for the BNZ have vanished and the peaks are much broader for the BNZ and BNZ:β-CD-HCs. BNZ is also found to be a good candidate for anti-inflammatory, anti-oxidant, and anti-diabetic. The results showed an improved activity when it is in the form of HCs on a PAN medium. Making HCs of drugs could be significant in biological applications.

Electrospun PVA–Dextran Nanofibrous Scaffolds for Acceleration of Topical Wound Healing: Nanofiber Optimization, Characterization and In Vitro Assessment

Electrospun polyvinyl alcohol–dextran (PVA–Dex)-based nanofibers (NFs) are explored as a novel class of bioactive injury dressing materials, which have an essential role for topical injury mending. Sodium ampicillin-loaded citric acid-cross-linked PVA–Dex NFs were fabricated by electrospinner for wound recuperating purposes. Results revealed that PVA (10%)–dextran (10%) cross-linked with 5% citric acid (CA) was chosen as an optimized condition for obtaining non-beaded and morphological accepted nanofibers. Altered concentrations of CA as cross-linker progressively enhanced significantly the mechanical/thermal stability and wettability-proof of NFs scaffolds, compared to un-cross-linked (PVA–Dex) scaffolds. Meanwhile, swelling (%), protein adsorption and released ampicillin of NFs decreased dramatically with the increase in the CA concentration, and conversely enhanced with increasing dextran concentrations. Interestingly, resultant PVA–Dex NFs with high concentrations of dextran promoted the proliferation ofHFB-4cells in a high concentration-dependent manner and high antimicrobial activity behavior, compared to NFs containing high concentrations of CA cross-linker after 24 and 48 h of cell exposure. Notably, all fabricated NFs have remarked ability to accelerate the rate of in vitro wound gap closure (%) after treatment for 24 and 48 h, compared to control sample. However, reducing CA concentration in NFs showed the highest percentages of wound healing for scratchedHFB-4cells with clear observed healing process.

Improving the thermal stability of natural bioactive ingredients via encapsulation technology

Bioactive compounds (bioactives) such as phenolic acids, coumarins, flavonoids, lignans and carotenoids have a marked improvement effect on human health by acting on body tissues or cells. Nowadays, with increasing levels of knowledge, consumers prefer foods that can provide bioactives beside the necessary nutrients (e.g., vitamins, essential fatty acids and minerals). However, an important barrier for incorporating bioactives into foods is their low thermal stability. Nevertheless, thermal processing is widely used by the food industries to achieve food safety and desired texture. The aim of this work is to give an overview of encapsulation technology to improve thermal stability of bioactives incorporated into different food products. Almost all thermal analysis and non-thermal methods in the literature suggest that incorporation of bioactives into different walls can effectively improve the thermal stability of bioactives. The level of such thermal enhancement depends on the strength of the bioactive interaction and wall molecules. Furthermore, contradictory results have been reported in relation to the effect of encapsulation technique using the same wall on thermal stability of bioactives. To date, the potential to increase the thermal resistance of various bioactives by gums, carbohydrates, and proteins have been extensively studied. However, further studies on the comparison of walls and encapsulation methods to form thermally stable carriers seem to be needed. In this regard, the same nature of bioactives and the specific protocol in the report of study results should be considered to compare the data and select the optimum conditions of encapsulation to achieve maximum thermal stability.

An Investigation of Electrospun Clerodendrum phlomidis Leaves Extract Infused Polycaprolactone Nanofiber for In Vitro Biological Application

The in vitro antibacterial, anticancer, and antioxidant activities of a few plant extracts were widely known for decades, and they were used for application in the conventional way. Specifically, electrospun nanofibrous mats have recently exhibited great antibacterial, anticancer, and antioxidant activities. The herbal extracts infused into these formations are expected to have a more efficient and integrated effect on in vitro biological applications. The purpose of this study is to develop polycaprolactone- (PCL-) based nanofiber mats that are infused with a traditional plant extract using Clerodendrum phlomidis leaves to improve the synthesized nanofibers' antibacterial, anticancer, and antioxidant efficacy. This study examined the morphology, thermal properties, mechanical properties, structure, and in vitro drug release studies of electrospun nanofibers. Antibacterial, anticancer, and antioxidant activities of the electrospun nanofibrous mats were also studied. The HRTEM and FESEM pictures of PCL and PCL-CPM nanofibers provide that smooth, defect-free, and homogeneous nanofibers were found to be 602.08 ± 75 nm and 414.15 ± 82 nm for PCL and PCL-CPM nanofibers, respectively. The presence of Clerodendrum phlomidis extract in the electrospun nanofibers was approved by UV-visible and FTIR spectroscopy. The incorporation of Clerodendrum phlomidis extract to nanofiber mats resulted in substantial antibacterial activity against bacterial cells. PCL-CPM mats exposed to oral cancer (HSC-3) and renal cell carcinoma (ACHN) cell lines displayed promising anticancer activity with less than 50% survival rate after 24 h of incubation. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) assay performed on PCL-CPM nanofibers revealed the antioxidant scavenging activity with maximum inhibition of 34% suggesting the role of the secondary metabolites release from scaffold. As a result, the findings of this study revealed that Clerodendrum phlomidis extract encapsulating PCL electrospun nanofibers has a high potential for usage as a biobased antibacterial, anticancer, and antioxidant agent.

Complexation of phytochemicals with cyclodextrins and their derivatives- an update

Bioactive phytochemicals from natural source have gained tremendous interest over several decades due to their wide and diverse therapeutic activities playing key role as functional food supplements, pharmaceutical and nutraceutical products. Nevertheless, their application as therapeutically active moieties and formulation into novel drug delivery systems are hindered due to major drawbacks such as poor solubility, bioavailability and dissolution rate and instability contributing to reduction in bioactivity. These drawbacks can be effectively overcome by their complexation with different cyclodextrins. Present article discusses complexation of phytochemicals varying from flavonoids, phenolics, triterpenes, and tropolone with different natural and synthetic cyclodextrins. Moreover, the article summarizes complexation methods, complexation efficiency, stability, stability constants and enhancement in rate and extent of dissolution, bioavailability, solubility, in vivo and in vitro activities of reported complexed phytochemicals. Additionally, the article presents update of published patent details comprising of complexed phytochemicals of therapeutic significance. Thus, phytochemical cyclodextrin complexes have tremendous potential for transformation into drug delivery systems as substantiated by significant outcome of research findings.

Active PLA Packaging Films: Effect of Processing and the Addition of Natural Antimicrobials and Antioxidants on Physical Properties, Release Kinetics, and Compostability

The performance characteristics of polylactic acid (PLA) as an active food packaging film can be highly influenced by the incorporation of active agents (AAs) into PLA, and the type of processing technique. In this review, the effect of processing techniques and the addition of natural AAs on the properties related to PLA performance as a packaging material are summarized and described through a systematic analysis, giving new insights about the relation between processing techniques, types of AA, physical–mechanical properties, barriers, optical properties, compostability, controlled release, and functionalities in order to contribute to the progress made in designing antioxidant and antimicrobial PLA packaging films. The addition of AAs into PLA films affected their optical properties and influenced polymer chain reordering, modifying their thermal properties, functionality, and compostability in terms of the chemical nature of AAs. The mechanical and barrier performance of PLA was affected by the AA’s dispersion degree and crystallinity changes resulting from specific processing techniques. In addition, hydrophobicity and AA concentration also modified the barrier properties of PLA. The release kinetics of AAs from PLA were tuned, modifying diffusion coefficient of the AAs in terms of the different physical properties of the films that resulted from specific processing techniques. Several developments based on the incorporation of antimicrobial and antioxidant substances into PLA have displayed outstanding activities for food protection against microbial growth and oxidation.

Starch inclusion complex for the encapsulation and controlled release of bioactive guest compounds

The linear component of starch, especially amylose, is capable of forming inclusion complex (IC) with various small molecules. It could significantly modify the structure and properties of starch, and it could bring beneficial effects when bioactive compounds can be encapsulated. This review discusses the formation and characterization of the starch-guest IC and focuses on the recent developments in the use of starch ICs for the encapsulation and controlled release of bioactive guest compounds. A great number of guest compounds, such as lipids, aroma compounds, pharmaceuticals, and phytochemicals, were studied for their ability to be complexed with starch and/or amylose and some of the formed ICs were evaluated for the chemical stability improvement and the guest release regulation. Starch-guest ICs has a great potential to be a delivery system, as most existing studies demonstrated the enhancement on guest retention and the possibility of controlled release.

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.

Multifaceted role of phyto-derived polyphenols in nanodrug delivery systems

As naturally occurring bioactive products, several lines of evidence have shown the potential of polyphenols in the medical intervention of various diseases, including tumors, inflammatory diseases, and cardiovascular diseases. Notably, owing to the particular molecular structure, polyphenols can combine with proteins, metal ions, polymers, and nucleic acids providing better strategies for polyphenol-delivery strategies. This contributes to the inherent advantages of polyphenols as important functional components for other drug delivery strategies, e.g., protecting nanodrugs from oxidation as a protective layer, improving the physicochemical properties of carbohydrate polymer carriers, or being used to synthesize innovative functional delivery vehicles. Polyphenols have emerged as a multifaceted player in novel drug delivery systems, both as therapeutic agents delivered to intervene in disease progression and as essential components of drug carriers. Although an increasing number of studies have focused on polyphenol-based nanodrug delivery including epigallocatechin-3-gallate, curcumin, resveratrol, tannic acid, and polyphenol-related innovative preparations, these molecules are not without inherent shortcomings. The active biochemical characteristics of polyphenols constitute a prerequisite to their high-frequency use in drug delivery systems and likewise to provoke new challenges for the design and development of novel polyphenol drug delivery systems of improved efficacies. In this review, we focus on both the targeted delivery of polyphenols and the application of polyphenols as components of drug delivery carriers, and comprehensively elaborate on the application of polyphenols in new types of drug delivery systems. According to the different roles played by polyphenols in innovative drug delivery strategies, potential limitations and risks are discussed in detail including the influences on the physical and chemical properties of nanodrug delivery systems, and their influence on normal physiological functions inside the organism.

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.

Electrospun poly (vinyl alcohol) nanofibers incorporating caffeic acid/cyclodextrins through the supramolecular assembly for antibacterial activity

Here, we prepared the solid inclusion complexes between Caffeic acid (CA) and Cyclodextrins (β- and γ-CDs) (CA/CDs) that were effectively embedded into Poly (vinyl alcohol) (PVA) electrospun nanofibers via electrospinning technique to enhanced solubility and antibacterial activity. In tested Cyclodextrins are β-and γ-CDs with CA in the ratio of 1:1 resulting in the formation of CA/CDs by co-precipitation method. The physical properties of CA/CDs were examined by FT-IR, UV, and Raman Spectroscopy. The phase solubility test showed a much higher solubility of CA due to inclusion complexes (ICs). Furthermore, CA/β-CD and CA/γ-CD perfected achieved 0.70:1 and 0.80:1 the molar ratio of ICs, confirmed by NMR studies. The fiber size distribution, average diameter, and morphology features were evaluated by SEM analysis. The dissolution profile of PVA/CA and PVA/CA/CDs were tested within 150 min, resulting in CA dissolved in PVA/CA/CDs slightly higher than PVA/CA nanofibers due to enhanced solubility of ICs. Moreover, PVA/CA/CDs exhibit high antibacterial activity against gram-positive bacteria of E-Coli and gram-negative bacteria of S. aureus. Finally, these results suggest that PVA/CA/CDs may be promising materials for active food packaging applications.

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.

Electrospinning and cyclodextrin inclusion complexes: An emerging technological combination for developing novel active food packaging materials

This review was focused on describing the combination of electrospinning and cyclodextrin inclusion complexes as one of the newest alternatives for the development of food packaging materials with antimicrobial and/or antioxidant properties. The advantages of this technological combination, the routes to design the active materials, the characterization and application of such materials were reviewed. Electrospinning has allowed developing active packaging materials composed by fibrillary structures with a high ratio surface-to-volume. On the other hand, cyclodextrin inclusion complexes have maintained the properties of active compounds when they have been incorporated in packaging materials. Both methods have been recently combined and novel active food packaging materials have been obtained through three different routes. Polymeric solutions containing preformed (route 1) or in-situ formed (route 2) cyclodextrin inclusion complexes have been electrospun to obtain packaging materials. Furthermore, cyclodextrin inclusion complexes solutions have been directly electrospun (route 3) in order to produce those materials. The developed packaging materials have exhibited a high active compound loading with a long lasting release. Therefore, the protection of different foodstuff against microbial growth, oxidation and quality decay as well as the maintenance of their physical and sensory properties have been achieved when those materials were applied as active packaging.

Functionalization of Gold Nanostars with Cationic β-Cyclodextrin-Based Polymer for Drug Co-Loading and SERS Monitoring

Gold nanostars (AuNSs) exhibit modulated plasmon resonance and have a high SERS enhancement factor. However, their low colloidal stability limits their biomedical application as a nanomaterial. Cationic β-cyclodextrin-based polymer (CCD/P) has low cytotoxicity, can load and transport drugs more efficiently than the corresponding monomeric form, and has an appropriate cationic group to stabilize gold nanoparticles. In this work, we functionalized AuNSs with CCD/P to load phenylethylamine (PhEA) and piperine (PIP) and evaluated SERS-based applications of the products. PhEA and PIP were included in the polymer and used to functionalize AuNSs, forming a new AuNS-CCD/P-PhEA-PIP nanosystem. The system was characterized by UV–VIS, IR, and NMR spectroscopy, TGA, SPR, DLS, zeta potential analysis, FE-SEM, and TEM. Additionally, Raman optical activity, SERS analysis and complementary theoretical studies were used for characterization. Minor adjustments increased the colloidal stability of AuNSs. The loading capacity of the CCD/P with PhEA-PIP was 95 ± 7%. The physicochemical parameters of the AuNS-CCD/P-PhEA-PIP system, such as size and Z potential, are suitable for potential biomedical applications Raman and SERS studies were used to monitor PhEA and PIP loading and their preferential orientation upon interaction with the surface of AuNSs. This unique nanomaterial could be used for simultaneous drug loading and SERS-based detection.

Core-shell chitosan/PVA-based nanofibrous scaffolds loaded with Satureja mutica or Oliveria decumbens essential oils as enhanced antimicrobial wound dressing

Wounds are prone to bacterial infections, which cause a delayed healing process. Regarding the emergence of bacterial resistance to common antibiotics, using natural antimicrobial agents can be beneficial. Chitosan is a biological polymer, which has shown partial antioxidant and antimicrobial activities. In this study, core-shell nanofibrous scaffolds composed of chitosan (CS)/polyvinyl alcohol (PVA) as the core and polyvinylpyrrolidone (PVP)/ maltodextrin (MD) as the shell were developed. Satureja mutica (S. mutica) or Oliveria decumbens (O. decumbens) essential oil (EO) was encapsulated into the core of the produced scaffolds. The broth microdilution analysis showed significant antimicrobial activity of the EOs. The SEM analysis indicated that the unloaded and loaded core-shell scaffolds with S. mutica or O. decumbens EO had a uniform, beadless structure with fiber mean diameters of 210 ± 50, 250 ± 45, and 225 ± 46 nm, respectively. The CS/PVA-PVP/MD and CS/PVA/EO-PVP/MD scaffolds indicated suitable mechanical properties. The addition of the studied EOs enhanced the antioxidant activity of the scaffolds. The antimicrobial test of produced scaffolds showed that loading of 10% S. mutica or O. decumbens EO could broaden the microbicidal activity of the CS/PVA-PVP/MD scaffolds. These results revealed that the CS/PVA/EO-PVP/MD nanofibrous scaffolds are promising candidates for wound dressing.

Preparation, characterization and therapeutic properties of gum arabic-stabilized gallic acid nanoparticles

Gallic acid (GA) is a natural phenolic compound with therapeutic effects that are often challenged by its rapid metabolism and clearance. Therefore,  GA was encapsulated using gum arabic into nanoparticles to increase its bioavailability. The formulated nanoparticles (GANPs) were characterized for physicochemical properties and size and were then evaluated for antioxidant and antihypertensive effects using various established in vitro assays, including 1,1-diphenyl-2-picrylhydrazyl (DPPH), nitric oxide scavenging (NO), β-carotene bleaching and angiotensin-converting enzyme (ACE) inhibitory assays. The GANPs were further evaluated for the in vitro cytotoxicity, cell uptake and cell migration in four types of human cancer cell lines including (MCF-7, MDA-MB231) breast adenocarcinoma, HepG2 hepatocellular cancer, HT-29 colorectal adenocarcinoma, and MCF-10A breast epithelial cell lines. The GANPs demonstrated potent antioxidant effects and have shown promising anti-cancer properties in a dose-dependent manner with a predilection toward HepG2 and MCF7 cancer cells. The uptake of GANPs was successful in the majority of cancer cells with a propensity to accumulate in the nuclear region of the cells. The HepG2 and MCF7 cancer cells also had a significantly higher percentage of apoptosis and were more sensitive to gallic acid nanoparticle treatment in the cell migration assay. This study is the first to confirm the synergistic effects of gum arabic in the encapsulation of gallic acid by increasing the selectivity towards cancer cells and enhancing  the antioxidant properties. The formulated nanoparticles also had remarkably low toxicity in normal cells. Based on these findings, GANPs may have promising therapeutic applications towards the development of more effective treatments with a probable targeting precision in cancer cells.

Biocompatible Polymers Combined with Cyclodextrins: Fascinating Materials for Drug Delivery Applications

Cyclodextrins (CD) are a group of cyclic oligosaccharides with a cavity/specific structure that enables to form inclusion complexes (IC) with a variety of molecules through non-covalent host-guest interactions. By an elegant combination of CD with biocompatible, synthetic and natural polymers, different types of universal drug delivery systems with dynamic/reversible properties have been generated. This review presents the design of nano- and micro-carriers, hydrogels, and fibres based on the polymer/CD supramolecular systems highlighting their possible biomedical applications. Application of the most prominent hydrophobic aliphatic polyesters that exhibit biodegradability, represented by polylactide and polycaprolactone, is described first. Subsequently, particular attention is focused on materials obtained from hydrophilic polyethylene oxide. Moreover, examples are also presented for grafting of CD on polysaccharides. In summary, we show the application of host-guest interactions in multi-component functional biomaterials for controlled drug delivery.

A review on techniques utilized for design of controlled release food active packaging

Active packaging (AP) is a new class of innovative food packaging, containing bioactive compounds, is able to maintain the quality of food and extend its shelf life by releasing active agent during storage. The main challenge in designing the AP system is slowing the release rate of active compounds for its prolonged activity. Controlled-release active packaging (CRP) is an innovative technology that provides control in the release of active compounds during storage. Various approaches have been proposed to design CRP. The purpose of this review was to gather and present the strategies utilized for release controlling of active compounds from food AP systems. The chemical modification of polymers, the preparation of multilayer films and the use of cross-linking agents are some methods tried in the last decades. Other approaches use molecular complexes and irradiation treatments. Micro- or nano-encapsulation of active compounds and using nano-structured materials in the AP film matrix are the newest techniques used for the preparation of CRP systems. The action mechanism for each technique was described and an effort was made to highlight representative published papers about each release controlling approach. This review will benefit future prospects of exploring other innovative release controlling methods in food CRP.

Preparation and Characterization of an Electrospun PLA-Cyclodextrins Composite for Simultaneous High-Efficiency PM and VOC Removal

Electrospinning is known to be a facile and effective technique to fabricate fibers of a controlled diameter-distribution. Among a multitude of polymers available for the purpose, the attention should be addressed to the environmentally compatible ones, with a special focus on sustainability. Polylactic acid (PLA) is a widespread, non-toxic polymer, originating from renewable sources and it can degrade into innocuous products. While the production of fibrous membranes is attractive for airborne particles filtration applications, their impact on the removal of gaseous compounds is generally neglected. In this study, electrospun PLA-based nanofibers were functionalized with cyclodextrins, because of their characteristic hydrophobic central cavity and a hydrophilic outer surface, in order to provide adsorptive properties to the composite. The aim of this work is to investigate a hybrid composite, from renewable sources, for the combined filtration of particulate matter (PM) and adsorption of volatile organic compounds (VOCs). Results show how their inclusion into the polymer strongly affects the fiber morphology, while their attachment onto the fiber surface only positively affects the filtration efficiency.