Enhancing the Solubility, Stability, and Bioavailability of Retinol Acetate through Mechanochemistry

This study utilizes mechanochemistry to prepare retinol acetate (RA) solid dispersion (RA-sodium starch octenyl succinate (SSOS)), resulting in improved solubility, stability, and bioavailability compared with raw RA and commercial RA microcapsules. RA, poloxamer 188, SSOS, and milling beads (8 mm) were mixed in a ratio of 2:1:8:220 (w/w) and ball-milled at 100 rpm for 3 h. RA-SSOS exhibited a solubility of 1020.35 μL/mL and a 98.09% retention rate after aging at 30 °C. Rats fed with RA-SSOS showed an ∼30% increase in organ RA content. Characterization analysis attributed the solubility and stabilization of RA-SSOS to hydrogen bonding between RA and SSOS, along with an amorphous state. RA-SSOS offers significant advantages for the pharmaceutical and food industries, leveraging mechanochemistry to enhance solid dispersions for hydrophobic compounds and optimize drug delivery.

Cyclodextrins and their potential applications for delivering vitamins, iron, and iodine for improving micronutrient status

Cyclodextrins (CDs) have been investigated as potential biopolymeric carriers that can form inclusion complexes with numerous bioactive ingredients. The inclusion of micronutrients (e.g. vitamins or minerals) into cyclodextrins can enhance their solubility and provide oxidative or thermal stability. It also enables the formulation of products with extended shelf-life. The designed delivery systems with CDs and their inclusion complexes including electrospun nanofibers, emulsions, liposomes, and hydrogels, show potential in enhancing the solubility and oxidative stability of micronutrients while enabling their controlled and sustained release in applications including food packaging, fortified foods and dietary supplements. Nano or micrometer-sized delivery systems capable of controlling burst release and permeation, or moderating skin hydration have been reported, which can facilitate the formulation of several personal and skin care products for topical or transdermal delivery of micronutrients. This review highlights recent developments in the application of CDs for the delivery of micronutrients, i.e. vitamins, iron, and iodine, which play key roles in the human body, emphasizing their existing and potential applications in the food, pharmaceuticals, and cosmeceuticals industries.

Fabrication of 3D Printed, Core-and-Shell Implants as Controlled Release Systems for Local siRNA Delivery

The development and clinical translation of small interfering RNA (siRNA) therapies remains challenging owing to their poor pharmacokinetics. 3D printing technology presents a great opportunity to fabricate personalized implants for local and sustained delivery of siRNA. Hydrogels can mimic the mechanical properties of tissues, avoiding the problems associated with rigid implants. Herein, a thermoresponsive composite hydrogel suitable for extrusion 3D-printing is formulated to fabricate controlled-release implants loaded with siRNA-Lipofectamine RNAiMAX complexes. A hydrogel matrix mainly composed of uncharged agarose to protect siRNA from decomplexation is selected. Additionally, pluronic F127 and gelatin are added to improve the printability, degradation, and cell adhesion to the implants. To avoid exposing siRNA to thermal stress during the printing process, a core-and-shell design is set up for the implants in which a core of siRNA-complexes loaded-pluronic F127 is printed without heat and enclosed with a shell comprising the thermoresponsive composite hydrogel. The release profile of siRNA-complexes is envisioned to be controlled by varying the printing patterns. The results reveal that the implants sustain siRNA release for one month. The intactness of the released siRNA-complexes is proven until the eighth day. Furthermore, by changing the printing patterns, the release profiles can be tailored.

Layer-by-layer coated calcium carbonate nanoparticles for targeting breast cancer cells

Breast cancer is resistant to conventional treatments due to the specific tumour microenvironment, the associated acidic pH and the overexpression of receptors that enhance cells tumorigenicity. Herein, we optimized the synthesis of acidic resorbable calcium carbonate (CaCO3) nanoparticles and the encapsulation of a low molecular weight model molecule (Rhodamine). The addition of ethylene glycol during the synthetic process resulted in a particle size decrease: we obtained homogeneous CaCO3 particles with an average size of 564 nm. Their negative charge enabled the assembly of layer-by-layer (LbL) coatings with surface-exposed hyaluronic acid (HA), a ligand of tumour-associated receptor CD44. The coating decreased Rhodamine release by two-fold compared to uncoated nanoparticles. We demonstrated the effect of nanoparticles on two breast cancer cell lines with different aggressiveness - SK-BR-3 and the more aggressive MDA-MB-231 - and compared them with the normal breast cell line MCF10A. CaCO3 nanoparticles (coated and uncoated) significantly decreased the metabolic activity of the breast cancer cells. The interactions between LbL-coated nanoparticles and cells depended on HA expression on the cell surface: more particles were observed on the surface of MDA-MB-231 cells, which had the thickest endogenous HA coating. We concluded that CaCO3 nanoparticles are potential candidates to carry low molecular weight chemotherapeutics and deliver them to aggressive breast cancer sites with an HA-abundant pericellular matrix.

Antioxidant effect on shear bond strength of orthodontic brackets after tooth bleaching: A scoping review of in vitro studies

INTRODUCTION

Tooth bleaching was reported to decrease bond strength of orthodontic brackets. The antioxidant application was investigated to reverse the bleaching effect for immediate bracket bonding. This scoping review of in vitro studies is to assess systematically the effect of antioxidant application on shear bond strength (SBS) before orthodontic bracket bonding after tooth bleaching.

MATERIALS AND METHODS

This review was provided according to the Preferred reporting items for systematic reviews and meta-analyses extension for scoping reviews (PRISMA-ScR) guidelines. An electronic literature search was performed for full-text articles in English via Scopus, Web of Science, MEDLINE/PubMed, and Google Scholar databases from 2012 to May 9, 2023.

RESULTS

A total of 549 records were retrieved from the electronic search, and 361 after discarding duplicates. According to eligibility criteria, 23 records were included in this study.

CONCLUSION

Included studies revealed that antioxidants could increase the SBS of brackets after bleaching. However, there was controversiality whether SBS was just improved or restored to the unbleached level according to various factors, including the antioxidant type, concentration, application time, and form. Most studies reported that 10% sodium ascorbate (SA), ascorbic acid, green tea (GT), and tocopherol solutions restored SBS of metal brackets but not ceramic brackets. The result of 10% SA and GT gel was controversial. Lower concentrations than 10% was effective with pink bark, grape seed, quercetin flavonoid, and chamomile to restore SBS. The included studies revealed that retinol acetate, gooseberry, and dimethyl sulfoxide did not restore SBS.

Fabrication of polycaprolactone electrospun fibres with retinyl acetate for antioxidant delivery in a ROS-mimicking environment

Background: Increased cancer rates denote that one in two people will be diagnosed with cancer in their lifetime. Over 60% of cancer patients receive radiotherapy, either as a stand-alone treatment or in combination with other treatments such as chemotherapy and surgery. Whilst radiotherapy is effective in destroying cancer cells, it also causes subsequent damage to healthy cells and surrounding tissue due to alterations in the tumor microenvironment and an increase in reactive oxygen species (ROS). This can cause extensive damage that impairs tissue function, and the likelihood of tissue regeneration and restoration of function is significantly reduced as new healthy cells cannot survive in the damaged environment. In the treatment of head and neck cancers, radiotherapy can cause salivary gland dysfunction. This significantly impairs the patient's quality of life and there is currently no cure, only palliative treatment options. Tissue engineering approaches are used to mimic the microenvironment of the tissue and can mediate the damaged microenvironment via bioactive compounds, to support the delivery, survival, and proliferation of new, healthy cells into the damaged environment. Methods: In this study, retinyl acetate, a derivative of vitamin A, was successfully incorporated into electrospun polycaprolactone fibres. Results: SEM images and characterization analyses showed that all scaffolds produced had similar characteristics, including fiber morphology and scaffold wettability. The vitamin scaffolds were shown to exert an antioxidant effect through scavenging activity of both DPPH and hydroxyl radicals in vitro. Critically, the antioxidant scaffolds supported the growth of human submandibular gland cells and significantly upregulated the expression of GPx1, an antioxidant enzyme, when cultured under both normal conditions and under a simulated oxidative stress environment. Discussion: These results suggest that incorporation of retinyl acetate into electrospun fibres has may mediate the damaged microenvironment post cancer radiation therapy.

Hypericum perforatum Oil and Vitamin A Palmitate-Loaded Gelatin Nanofibers Cross-Linked by Tannic Acid as Wound Dressings

Recent studies in wound dressing applications offer new therapies to promote the wound healing process. The main strategy of this study is to combine the traditional perspective of using medicinal oils with polymeric scaffolds manufactured by an engineering approach to fabricate a potential tissue engineering product that provides both new tissue formation and wound healing. Thus, Hypericum perforatum oil (HPO) and vitamin A palmitate (VAP) incorporated gelatin (Gt) nanofibrous scaffolds were successfully prepared by the electrospinning method. Tannic acid (TA) was used as the cross-linking agent. The amounts of VAP and HPO loaded in the base Gt solution [15% w/v in 4:6 v/v acetic acid/deionized water] were 5 and 50 wt % (based on the weight of Gt), respectively. The obtained scaffolds were studied regarding their microstructure, chemical structure, thermal stability, antibacterial activity, in vitro release study, and cellular proliferation assay. In the light of these studies, it was determined that VAP and HPO were incorporated successfully in Gt nanofibers cross-linked with TA. Release kinetic tests confirmed that the patterns of TA and VAP release were consistent with the Higuchi model, whereas HPO release was consistent with the first-order kinetic model. In addition, this membrane was biocompatible with L929 fibroblast cells and had antibacterial activity and thermal stability. This preliminary study suggests potential applicability of the proposed dressing to treat skin wounds in clinics.

Fabrication, Physical-Chemical and Biological Characterization of Retinol-Loaded Poly(vinyl Alcohol) Electrospun Fiber Mats for Wound Healing Applications

Nowadays, there exists a huge interest in producing innovative, high-performance, biofunctional, and cost-efficient electrospun biomaterials based on the association of biocompatible polymers with bioactive molecules. Such materials are well-known to be promising candidates for three-dimensional biomimetic systems for wound healing applications because they can mimic the native skin microenvironment; however, many open questions such as the interaction mechanism between the skin and the wound dressing material remain unclear. Recently, several biomolecules were intended for use in combination with poly(vinyl alcohol) (PVA) fiber mats to improve their biological response; nevertheless, retinol, an important biomolecule, has not been combined yet with PVA to produce tailored and biofunctional fiber mats. Based on the abovementioned concept, the present work reported the fabrication of retinol-loaded PVA electrospun fiber mats (RPFM) with a variable content of retinol (0 ≤ Ret ≤ 25 wt.%), and their physical-chemical and biological characterization. SEM results showed that fiber mats exhibited diameters distribution ranging from 150 to 225 nm and their mechanical properties were affected with the increasing of retinol concentrations. In addition, fiber mats were able to release up to 87% of the retinol depending on both the time and the initial content of retinol. The cell culture results using primary mesenchymal stem cell cultures proved the biocompatibility of RPFM as confirmed by their effects on cytotoxicity (low level) and proliferation (high rate) in a dose-dependent manner. Moreover, the wound healing assay suggested that the optimal RPFM with retinol content of 6.25 wt.% (RPFM-1) enhanced the cell migratory activity without altering its morphology. Accordingly, it is demonstrated that the fabricated RPFM with retinol content below the threshold 0 ≤ Ret ≤ 6.25 wt.% would be an appropriate system for skin regenerative application.

Encapsulation of antioxidant beta-carotene by cyclodextrin complex electrospun nanofibers: Solubilization and stabilization of beta-carotene by cyclodextrins

Carotenoids act as effective antioxidant defense systems in humans as they scavenge molecular oxygen and peroxyl radicals. However, their poor water solubility and being susceptible to degradation driven by light and oxygen hinder their bioactivity, therefore, they should be stabilized by host matrices against oxidation. Here, β-carotene was encapsulated in electrospun cyclodextrin (CD) nanofibers to increase its water-solubility and photostability to enhance its antioxidant bioactivity. β-carotene/CD complex aqueous solutions were electrospun into nanofibers. The bead-free morphology of the β-carotene/CD nanofibers was confirmed by SEM. The formation of β-carotene/CD complexes was explored through computational modeling and experimentally by FTIR, XRD and solubility tests. The antioxidant activity of the fibers exposed to UV irradiation was demonstrated via a free radical scavenger assay, where β-carotene/CD nanofibers revealed protection against UV radiation. Overall, this work reports the water-borne electrospinning of antioxidant β-carotene/CD inclusion complex nanofibers, which stabilize the encapsulated β-carotene against UV-mediated oxidation.

Preparation, Characterization, and Antioxidant Activity of L-Ascorbic Acid/HP-β-Cyclodextrin Inclusion Complex-Incorporated Electrospun Nanofibers

L-Ascorbic acid (LAA) is a key vitamin, implicated in a variety of physiological processes in humans. Due to its free radical scavenging activity, it is extensively employed as an excipient in pharmaceutical products and food supplements. However, its application is greatly impeded by poor thermal and aqueous stability. Herein, to improve the stability and inhibit oxidative degradation, we prepared LAA-cyclodextrin inclusion complex-incorporated nanofibers (NFs). The continuous variation method (Job plot) demonstrated that LAA forms inclusions with hydroxypropyl-β-cyclodextrin (HP-β-CD) at a 2:1 molar stoichiometric ratio. The NFs were prepared via the single step electrospinning technique, without using any polymer matrix. The solid-state characterizations of LAA/HP-β-CD-NF via powder x-ray diffractometry (PXRD), Fourier-transform infrared (FT-IR) analysis, differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA), and nuclear magnetic resonance (¹H NMR and 2D-NOESY) spectroscopy, reveal the effective encapsulation of the LAA (guest molecule) inside the HP-β-CD (host) cavity. The SEM micrograph reveals an average fiber diameter of ~339 nm. The outcomes of the thermal investigations demonstrated that encapsulation of LAA within HP-β-CD cavities provides improved thermal stability of LAA (by increasing the thermal degradation temperature). The radical scavenging assay demonstrated the enhanced antioxidant potential of LAA/HP-β-CD-NF, as compared to native LAA. Overall, the study shows that cyclodextrin inclusion complex-incorporated NFs, are an effective approach for improving the limitations associated with LAA, and provide promising avenues in its therapeutic and food applications.

Enrichment of Cellulose Acetate Nanofibrous Scaffolds with Retinyl Palmitate and Clove Essential Oil for Wound Healing Applications

The use of biocompatible materials and fabrication methods is of particular importance in the development of wound dressings. Cellulose acetate (CA) has excellent properties for wound dressing applications, but it is insufficient for the wound healing process due to its lack of bioactive and antibacterial properties. In this study, CA was electrospun with retinyl palmitate (RP) and clove essential oil (CLV) to fabricate a novel antibacterial and antioxidant biomaterial. The effects of RP and CLV incorporation on the surface morphology, fiber diameter, antioxidant activity, antibacterial activity, cell viability, and release behavior of the fabricated CA mats were investigated. In light of these studies, it was determined that the nanofiber mat, fabricated with a 15% w/v CA polymer concentration, a 1% w/w RP ratio, and a 5% w/w CLV ratio, was biocompatible with L929 fibroblast cells with antibacterial and antioxidant properties. Overall, results showed that this nanofiber offers promise for use as a wound dressing.

Cyclodextrin Derivatives as Promising Solubilizers to Enhance the Biological Activity of Rosmarinic Acid

Rosmarinic acid (RA) is a natural antioxidant with neuroprotective properties; however, its preventive and therapeutic use is limited due to its slight solubility and poor permeability. This study aimed to improve RA physicochemical properties by systems formation with cyclodextrins (CDs): hydroxypropyl-α-CD (HP-α-CD), HP-β-CD, and HP-γ-CD, which were prepared by the solvent evaporation (s.e.) method. The interactions between components were determined by X-ray powder diffraction (XRPD), differential scanning calorimetry (DSC) and Fourier Transform infrared spectroscopy (FTIR). The sites of interaction between RA and CDs were suggested as a result of in silico studies focused on assessing the interaction between molecules. The impact of amorphous systems formation on water solubility, dissolution rate, gastrointestinal (GIT) permeability, and biological activity was studied. RA solubility was increased from 5.869 mg/mL to 113.027 mg/mL, 179.840 mg/mL, and 194.354 mg/mL by systems formation with HP-α-CD, HP-β-CD, and HP-γ-CD, respectively. During apparent solubility studies, the systems provided an acceleration of RA dissolution. Poor RA GIT permeability at pH 4.5 and 5.8, determined by parallel artificial membrane permeability assay (PAMPA system), was increased; RA–HP-γ-CD s.e. indicated the greatest improvement (at pH 4.5 from P_app 6.901 × 10⁻⁷ cm/s to 1.085 × 10⁻⁶ cm/s and at pH 5.8 from 5.019 × 10⁻⁷ cm/s to 9.680 × 10⁻⁷ cm/s). Antioxidant activity, which was determined by DPPH, ABTS, CUPRAC, and FRAP methods, was ameliorated by systems; the greatest results were obtained for RA–HP-γ-CD s.e. The inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) was increased from 36.876% for AChE and 13.68% for BChE to a maximum inhibition of the enzyme (plateau), and enabled reaching IC₅₀ values for both enzymes by all systems. CDs are efficient excipients for improving RA physicochemical and biological properties. HP-γ-CD was the greatest one with potential for future food or dietary supplement applications.

Electrospinning of Biomedical Nanofibers/Nanomembranes: Effects of Process Parameters

Nanotechnology has attracted great attention from researchers in modern science because nanomaterials have innovative and superior physical, chemical, and biological properties, and they can be altered and modified accordingly. As particles get smaller, their surface area increases compared to their volume. Electrospinning is one of the advanced techniques to produce ultrathin nanofibers and membranes, and it is one of the best ways to create continuous nanomaterials with variable biological, chemical, and physical properties. The produced fibers can be utilized in various domains such as wound dressing, drug release, enzyme immobilization, etc. This review examines the biomedical nanofibers/membranes produced by electrospinning techniques to investigate the effects of process parameters (e.g., solution characteristics, applied voltage, and ambient conditions) on nanofiber characteristics (physical, chemical, and mechanical properties). The solution parameters like (i) optimum concentration, (ii) higher molecular weight, and (iii) higher conductivity produce uniform nanofibers, smoother nanofibers, and a smaller and more uniform fiber diameter, respectively. In addition, process parameters such as (i) higher voltage and (ii) slower flow rate produce more polymer ejection from the nozzle and enhance the smoother fiber production, respectively. The optimum tip-to-collector distance is considered to be 13-15 cm. The ambient conditions such as (i) higher humidity and (ii) higher temperature produce thicker and thinner nanofibers, respectively. The controlled parameters through optimization process determine the size and quality of the fibers. The effects of each parameter are discussed in this review. The applications of nanofibers are also discussed.

Fabrication and Characterization of Antifungal Hydroxypropyl-β-Cyclodextrin/Pyrimethanil Inclusion Compound Nanofibers Based on Electrospinning

Pyrimethanil (PMT) is an anilinopyrimidine bactericide with poor water solubility, which limits its applications. To improve the physical and chemical properties of PMT, hydroxypropyl-β-cyclodextrin/pyrimethanil inclusion compound nanofibers (HPβCD/PMT-IC-NFs) were fabricated via electrospinning. A variety of analytical techniques were used to confirm the formation of the inclusion compound. Scanning electron microscopy image displayed that HPβCD/PMT-IC-NF was homogeneous without particles. Thermogravimetric analysis indicated that the formation of the inclusion compound improved the thermostability of PMT. In addition, the phase solubility test illustrated that the inclusion compound formed by PMT and HPβCD had a stronger water solubility. The antifungal effect test exhibited that HPβCD/PMT-IC-NF had better antifungal properties. The release experiment confirmed that HPβCD/PMT-IC-NF had a sustained-release effect, and the release curve conformed to the first-order kinetic model equation. In short, the fabrication HPβCD/PMT-IC-NF inhibited improved solubility and thermostability of PMT, thus promoting the development of pesticide dosage form to water-based and low-pollution direction.

Encapsulation of Caffeic Acid in Carob Bean Flour and Whey Protein-Based Nanofibers via Electrospinning

The purpose of this study was to introduce caffeic acid (CA) into electrospun nanofibers made of carob flour, whey protein concentrate (WPC), and polyethylene oxide (PEO). The effects of WPC concentration (1% and 3%) and CA additions (1% and 10%) on the characteristics of solutions and nanofibers were investigated. The viscosity and electrical conductivity of the solutions were examined to determine characteristics of solutions. Scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetric analyzer (TGA), differential scanning calorimetry (DSC), water vapor permeability (WVP), and Fourier transform infrared (FTIR) analysis were used to characterize the nanofibers. According to the SEM results, the inclusion of CA into nanofibers resulted in thinner nanofibers. All nanofibers exhibited uniform morphology. CA was efficiently loaded into nanofibers. When CA concentrations were 1% and 10%, loading efficiencies were 76.4% and 94%, respectively. Nanofibers containing 10% CA demonstrated 92.95% antioxidant activity. The results indicate that encapsulating CA into carob flour–WPC-based nanofibers via electrospinning is a suitable method for active packaging applications.

Recent Advances in Water-Soluble Vitamins Delivery Systems Prepared by Mechanical Processes (Electrospinning and Spray-Drying Techniques) for Food and Nutraceuticals Applications-A Review

Water-soluble vitamins are essential micronutrients in diets and crucial to biochemical functions in human body physiology. These vitamins are essential for healthy diets and have a preventive role against diseases. However, their limitations associated with high sensitivity against external conditions (temperature, light, pH, moisture, oxygen) can lead to degradation during processing and storage. In this context, microencapsulation may overcome these conditions, protecting a biomolecule’s bioavailability, stability, and effectiveness of delivery. This technique has been used to produce delivery systems based on polymeric agents that surround the active compounds. The present review focuses on the most relevant topics of water-soluble vitamin encapsulation using promising methods to produce delivery vehicles—electrohydrodynamic (electrospinning and electrospraying) and spray-drying techniques. An overview of the suitable structures produced by these processes is provided. The review introduces the general principles of the methods, advantages, disadvantages, and involved parameters. A brief list of the used physicochemical techniques for the systems’ characterization is discussed in this review. Electrospinning and spray-drying techniques are the focus of this investigation in order to guarantee vitamins’ bioaccessibility and bioavailability. Recent studies and the main encapsulating agents used for these micronutrients in both processes applied to functional food and nutraceutical areas are highlighted in this review.

Electrospun Nanofibers: Current Progress and Applications in Food Systems

Electrospinning has the advantages of simple manufacturing equipment, a low spinning cost, wide range of spinnable materials, and a controllable mild process, which can continuously fabricate submicron or nanoscale ultrafine polymer fibers without high temperature or high pressure. The obtained nanofibrous films may have a large specific surface area, unique pore structure, and easy-to-modify surface characteristics. This review briefly introduces the types and fiber structures of electrospinning and summarizes the applications of electrospinning for food production (e.g., delivery systems for functional food, filtration of beverages), food packaging (e.g., intelligent packaging, antibacterial packaging, antioxidant packaging), and food analysis (e.g., pathogen detection, antibiotic detection, pesticide residue detection, food compositions analysis), focusing on the advantages of electrospinning applications in food systems. Furthermore, the limitations and future research directions of the technique are discussed.

Microfluidic spinning of fucoxanthin-loaded nanofibers for enhancing antioxidation and clarification of fruit juice

Fruit juice is one of the most popular drinks, which requires strict processing conditions to ensure its quality, especially to prevent enzymatic browning and turbidity loss. In this work, a new strategy for the preparation of composite nanofibers for juice clarification and anti-browning control was proposed. The strategy used microfluidic spinning to combine Fucoxanthin (Fx), hydroxypropyl-γ-cyclodextrin (HP-γ-CD) and polyvinyl pyrrolidone (PVP) to prepare Fx/HP-γ-CD-PVP (PCF) nanofibers, which not only reflected the excellent antioxidant properties of cyclodextrin-wrapped Fx, but also achieved a more optimized juice clarification agent dosage. Molecular docking technique was used to prove that the stable inclusion complex of Fx and HP-γ-CD could be formed by hydrogen bonding when the molar ratio of Fx to HP-γ-CD was 1 : 2, and the binding energy was as low as -10.23 kcal mol^-1. SEM, XRD, FT-IR and TGA were used to characterize the structure of the composite nanofibers, which showed that the thermal stability and water solubility of the embedded Fx were improved. Further studies showed that the apple juice with PCF nanofibers containing inclusion complexes of Fx and HP-γ-CD at a molar ratio of 1 : 2 (PCF 1 : 2) could significantly improve the DPPH and ABTS radical scavenging activity, and could significantly protect the cell membrane integrity of RAW264.7 cells against H₂O₂ oxidative damage. Finally, the effects of PCF nanofibers on the quality of fresh juice were studied, including clarification experiment and sensory evaluation. The results showed that the dosage of PVP in PCF 1 : 2 was only about 4% of the conventional dosage, and the browning index of fresh juice was significantly reduced with the best clarification. The available data provided in this study would provide a promising safety strategy for the food processing of fresh juice and the extension of its storage life.

Preparation, characterization, and evaluation of HP-β-CD inclusion complex with alcohol extractives from star anise

The active compounds in star anise alcohol extractives (SAAE) have potent bioactivity. However, their poor solubility and stability limit their applications. In this study, SAAE/hydroxypropyl-β-cyclodextrin (HP-β-CD) inclusion complexes were prepared as a strategy to overcome the abovementioned disadvantages. The phase solubility results indicated that the solubility of the inclusion complex was enhanced. Complexation was confirmed by complementary methods, including Fourier-transform infrared spectroscopy, nuclear magnetic resonance spectroscopy, scanning electron microscopy, and transmission electron microscopy, which proved to be extremely insightful for studying the inclusion formation phenomenon between SAAE and HP-β-CD. Despite there being no apparent improvements in the antioxidant capacity and antimicrobial activity, the results of the stability studies presented higher thermal, volatile, and photostability after encapsulation. Further, molecular modeling was used to investigate the factors influencing complex formation and provide the most stable molecular conformation. Thus, based on the obtained results, this study strongly demonstrates the potential of the SAAE/HP-β-CD inclusion complex in the food industry.

Electrospun Polymer-Free Nanofibers Incorporating Hydroxypropyl-β-cyclodextrin/Difenoconazole via Supramolecular Assembly for Antifungal Activity

In this study, flexible and self-standing hydroxypropyl-β-cyclodextrin/difenoconazole inclusion complex (HPβCD/DZ-IC) nanofibers were prepared by polymer-free electrospinning, which exhibited potential to be a new fast-dissolving pesticide formulation. Scanning electron microscopy and optical microscopy were applied to evaluate the morphology of nanofibers, which showed that the resulting HPβCD/DZ-IC nanofibers were bead-free and uniform. In addition, the proton nuclear magnetic resonance (¹H NMR) spectrum suggested a stoichiometric ratio of 1:0.9 (HPβCD/DZ). Other characterization methods, such as UV-vis absorption, fluorescence spectroscopy, Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and thermogravimetric analysis (TGA), were applied in this study. On the one hand, UV-vis absorption, fluorescence spectroscopy, FT-IR, XRD, and TGA provided useful information for the successful formation of an inclusion complex; on the other hand, the results of TGA indicated the thermal stability of DZ was enhanced after the formation of inclusion complexes. Besides, the phase solubility test could explain the increased water solubility of the nanofibers of inclusion complexes formed by DZ and HPβCD. The results of molecular docking studies demonstrated the most favorable binding interactions when HPβCD combined with DZ. The dissolution test and the antifungal performance test exhibited the characteristics of fast dissolution and the excellent antifungal performance of HPβCD/DZ-IC nanofibers, respectively.

Polymer-free cyclodextrin and natural polymer-cyclodextrin electrospun nanofibers: A comprehensive review on current applications and future perspectives

The present review discusses the use of cyclodextrins and their derivatives to prepare electrospun nanofibers with specific features. Cyclodextrins, owing to their unique capability to form inclusion complexes with hydrophobic and volatile molecules, can indeed facilitate the encapsulation of bioactive compounds in electrospun nanofibers allowing fast-dissolving products for food, biomedical, and pharmaceutical purposes, filtering materials for wastewater and air purification, as well as a variety of other technological applications. Additionally, cyclodextrins can improve the processability of naturally occurring biopolymers helping the fabrication of "green" materials with a strong industrial relevance. Hence, this review provides a comprehensive state-of-the-art of different cyclodextrins-based nanofibers including those made of pure cyclodextrins, of polycyclodextrins, and those made of natural biopolymer functionalized with cyclodextrins. To this end, the advantages and disadvantages of such approaches and their possible applications are investigated along with the current limitations in the exploitation of electrospinning at the industrial level.

Thiram/hydroxypropyl-β-cyclodextrin inclusion complex electrospun nanofibers for a fast dissolving water-based drug delivery system

The electrospinning of thiram/hydroxypropyl-β-cyclodextrin inclusion complex nanofiber (thiram/HPβCD-IC-NF) was produced for establishing a quick dissolving water-based drug delivery system. As a dithiocarbamate broad-spectrum fungicide, thiram is insoluble in water. High-concentration HPβCD solutions (180 %, w/v) were applied in thiram/HPβCD systems to implement electrospinning with no extra polymer matrix added. The formation of thiram/HPβCD-IC-NF was identified by Fourier transform infrared spectroscopy, X-ray diffraction as well as nuclear magnetic resonance. Phase solubility study proved HPβCD played a huge role in the improvement in solubility of thiram, and thiram/HPβCD-IC-NF showed an excellent dissolution rate. Scanning electron microscopy was used to examine the configuration of surface of thiram/HPβCD-IC-NF, which exhibited that thiram/HPβCD-IC-NF was uniform and beadless. In addition, thiram/HPβCD-IC-NF exhibited better antifungal activity and thermal stability than pure thiram. In summary, thiram/HPβCD-IC-NF drug delivery system contributed to water solubility, thermal stability and antifungal activity of thiram. It could provide a new idea for the development of new formulations of rapidly dissolving green pesticides, and made efforts to promote the sustainable development of agriculture.