Electrospun chitosan-based nanofiber mats loaded with Garcinia mangostana extracts

Multifunctional polymeric nanofibrous scaffolds enriched with azilsartan medoxomil for enhanced wound healing

A prolonged and compromised wound healing process poses a significant clinical challenge, necessitating innovative solutions. This research investigates the potential application of nanotechnology-based formulations, specifically nanofiber (NF) scaffolds, in addressing this issue. The study focuses on the development and characterization of multifunctional nanofibrous scaffolds (AZL-CS/PVA-NF) composed of azilsartan medoxomil (AZL) enriched chitosan/polyvinyl alcohol (CS/PVA) through electrospinning. The scaffolds underwent comprehensive characterization both in vitro and in vivo. The mean diameter and tensile strength of AZL-CS/PVA-NF were determined to be 240.42 ± 3.55 nm and 18.05 ± 1.18 MPa, respectively. A notable drug release rate of 93.86 ± 2.04%, was observed from AZL-CS/PVA-NF over 48 h at pH 7.4. Moreover, AZL-CS/PVA-NF exhibited potent antimicrobial efficacy for Staphylococcus aureus and Pseudomonas aeruginosa. The expression levels of Akt and CD31 were significantly elevated, while Stat3 showed a decrease, indicating a heightened tissue regeneration rate with AZL-CS/PVA-NF compared to other treatment groups. In vivo ELISA findings revealed reduced inflammatory markers (IL-6, IL-1β, TNF-α) within treated skin tissue, implying a beneficial effect on injury repair. The comprehensive findings of the present endeavour underscore the superior wound healing activity of the developed AZL-CS/PVA-NF scaffolds in a Wistar rat full-thickness excision wound model. This indicates their potential as novel carriers for drugs and dressings in the field of wound care.

Electrospun wound dressings with antibacterial function: a critical review of plant extract and essential oil incorporation

Among the many different types of wound dressings, nanofiber-based materials produced through electrospinning are claimed to be ideal because of their advantageous intrinsic properties and the feasibility of employing several strategies to load bioactive compounds into their structure. Bioactive compounds with antimicrobial properties have been incorporated into different wound dressings to promote healing as well as prevent and treat bacterial infections. Among these, natural products, such as medicinal plant extracts and essential oils (EOs), have proven particularly attractive thanks to their nontoxic nature, minor side effects, desirable bioactive properties, and favorable effects on the healing process. To this end, the present review provides an exhaustive and up-to-date revision of the most prominent medicinal plant extracts and EOs with antimicrobial properties that have been incorporated into nanofiber-based wound dressings. The most common methods used for incorporating bioactive compounds into electrospun nanofibers include: pre-electrospinning (blend, encapsulation, coaxial, and emulsion electrospinning), post-electrospinning (physical adsorption, chemical immobilization, and layer-by-layer assembly), and nanoparticle loading. Furthermore, a general overview of the benefits of EOs and medicinal plant extracts is presented, describing their intrinsic properties and biotechniques for their incorporation into wound dressings. Finally, the current challenges and safety issues that need to be adequately clarified and addressed are discussed.

Generation of PVP Membranes Using Extracts/Phenolic Fraction of Dysphania ambrosioides, Opuntia ficus-indica, and Tradescantia pallida

In the present work, electrospun membranes of polyvinylpyrrolidone (PVP) nanofibers were manufactured using extracts and phenolic fractions of Dysphania ambrosioides (epazote), Opuntia ficus-indica (nopal), and Tradescantia pallida (chicken grass). The characterization of the membranes was carried out by scanning electron microscopy and Fourier transform infrared spectroscopy. The membranes synthesized through the use of the extracts generally showed a slight decrease in the diameter of the fibers but an increase in the size of the pores due to the presence of nanoparticles (rosaries) on the surface of the fibers, while the membranes synthesized using the phenolic fraction demonstrated an inversely proportional relationship between the compounds of this family with the diameter of the fibers and the size of the pore, allowing to elucidate part of the polymerization mechanisms of PVP nanofibers, in addition to proposing a reaction mechanism in the interaction between PVP and phenolic compounds for surface functionalization. Likewise, we demonstrate that the generation of reaction seeds through functionalization allows the addition of other compounds to the fibers in the membranes synthesized using the complete extract.

State-of-the-Art Review of Advanced Electrospun Nanofiber Composites for Enhanced Wound Healing

Wound healing is a complex biological process with four main phases: hemostasis, inflammation, proliferation, and remodeling. Current treatments such as cotton and gauze may delay the wound healing process which gives a demand for more innovative treatments. Nanofibers are nanoparticles that resemble the extracellular matrix of the skin and have a large specific surface area, high porosity, good mechanical properties, controllable morphology, and size. Nanofibers are generated by electrospinning method that utilizes high electric force. Electrospinning device composed of high voltage power source, syringe that contains polymer solution, needle, and collector to collect nanofibers. Many polymers can be used in nanofiber that can be from natural or from synthetic origin. As such, electrospun nanofibers are potential scaffolds for wound healing applications. This review discusses the advanced electrospun nanofiber morphologies used in wound healing that is prepared by modified electrospinning techniques.

3D printed Styrax Liquidus (Liquidambar orientalis Miller)-loaded poly (L-lactic acid)/chitosan based wound dressing material: Fabrication, characterization, and biocompatibility results

The medicinal plant of Styrax liquidus (ST) (sweet gum balsam) which extracted from Liquidambar orientalis Mill tree, was loaded into the 3D printed polylactic acid (PLA)/chitosan (CS) based 3D printed scaffolds to investigate its wound healing and closure effect, in this study. The morphological and chemical properties of the ST loaded 3D printed scaffolds with different concentrations (1 %, 2 %, and 3 % wt) were investigated by Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FT-IR), respectively. In addition, the mechanical and thermal properties of the materials were investigated by Tensile test and Differential Scanning Calorimetry (DSC), respectively. The antimicrobial activities of the ST loaded 3D printed scaffolds and their incubation media in the PBS (pH 7.4, at 37 °C for 24 h) were investigated on two Gram-positive and two Gram-negative standard pathogenic bacteria with the agar disc diffusion method. The colorimetric MTT assay was used to determine the cell viability of human fibroblast cells (CCD-1072Sk) incubated with free ST, ST loaded, and unloaded 3D printed scaffolds. The 1 % and 2 % (wt) ST loaded PLA/CS/ST 3D printed scaffolds showed an increase in the cell number. Annexin V/PI double stain assay was performed to test whether early or late apoptosis was induced in the PLA/CS/1 % ST and PLA/CS/2 % ST loaded groups and the results were consistent with the MTT assay. Furthermore, a wound healing assay was carried out to investigate the effect of ST loaded 3D printed scaffolds on wound healing in CCD-1072Sk cells. The highest wound closure compared to the control group was observed on cells treated with PLA/CS/1 % ST for 72 h. According to the results, novel biocompatible ST loaded 3D printed scaffolds with antimicrobial effect can be used as wound healing material for potential tissue engineering applications.

Advances in Natural Product Extraction Techniques, Electrospun Fiber Fabrication, and the Integration of Experimental Design: A Comprehensive Review

The present review explores the growing interest in the techniques employed for extracting natural products. It emphasizes the limitations of conventional extraction methods and introduces superior non-conventional alternatives, particularly ultrasound-assisted extraction. Characterization and quantification of bioactive constituents through chromatography coupled with spectroscopy are recommended, while the importance of method development and validation for biomarker quantification is underscored. At present, electrospun fibers provide a versatile platform for incorporating bioactive extracts and have extensive potential in diverse fields due to their unique structural and functional characteristics. Thus, the review also highlights the fabrication of electrospun fibers containing bioactive extracts. The preparation of biologically active extracts under optimal conditions, including the selection of safe solvents and cost-effective equipment, holds promising potential in the pharmaceutical, food, and cosmetic industries. Integration of experimental design into extraction procedures and formulation development is essential for the efficient production of health products. The review explores potential applications of encapsulating natural product extracts in electrospun fibers, such as wound healing, antibacterial activity, and antioxidant properties, while acknowledging the need for further exploration and optimization in this field. The findings discussed in this review are anticipated to serve as a valuable resource for the processing industry, enabling the utilization of affordable and environmentally friendly, natural, and raw materials.

Electrospun Food Polysaccharides Loaded with Bioactive Compounds: Fabrication, Release, and Applications

Food polysaccharides are well acclaimed in the field of delivery systems due to their natural safety, biocompatibility with the human body, and capability of incorporating/releasing various bioactive compounds. Electrospinning, a straightforward atomization technique that has been attracting researchers worldwide, is also versatile for coupling food polysaccharides and bioactive compounds. In this review, several popular food polysaccharides including starch, cyclodextrin, chitosan, alginate, and hyaluronic acid are selected to discuss their basic characteristics, electrospinning conditions, bioactive compound release characteristics, and more. Data revealed that the selected polysaccharides are capable of releasing bioactive compounds from as rapidly as 5 s to as prolonged as 15 days. In addition, a series of frequently studied physical/chemical/biomedical applications utilizing electrospun food polysaccharides with bioactive compounds are also selected and discussed. These promising applications include but are not limited to active packaging with 4-log reduction against E. coli, L. innocua, and S. aureus; removal of 95% of particulate matter (PM) 2.5 and volatile organic compounds (VOCs); heavy metal ion removal; increasing enzyme heat/pH stability; wound healing acceleration and enhanced blood coagulation, etc. The broad potentials of electrospun food polysaccharides loaded with bioactive compounds are demonstrated in this review.

A review on polysaccharides mediated electrospun nanofibers for diabetic wound healing: Their current status with regulatory perspective

The current treatment strategies for diabetic wound care provide only moderate degree of effectiveness; hence new and improved therapeutic techniques are in great demand. Diabetic wound healing is a complex physiological process that involves synchronisation of various biological events such as haemostasis, inflammation, and remodelling. Nanomaterials like polymeric nanofibers (NFs) offer a promising approach for the treatment of diabetic wounds and have emerged as viable options for wound management. Electrospinning is a powerful and cost-effective method to fabricate versatile NFs with a wide array of raw materials for different biological applications. The electrospun NFs have unique advantages in the development of wound dressings due to their high specific surface area and porosity. The electrospun NFs possess a unique porous structure and biological function similar to the natural extracellular matrix (ECM), and are known to accelerate wound healing. Compared to traditional dressings, the electrospun NFs are more effective in healing wounds owing to their distinct characteristics, good surface functionalisation, better biocompatibility and biodegradability. This review provides a comprehensive overview of the electrospinning procedure and its operating principle, with special emphasis on the role of electrospun NFs in the treatment of diabetic wounds. This review discusses the present techniques applied in the fabrication of NF dressings, and highlights the future prospects of electrospun NFs in medicinal applications.

Poly (l-lactic acid)-based modified nanofibrous membrane with dual drug release capability for GBR application

Electrospun multilayer nanofibers guided bone regeneration (GBR) with a new design were developed in this study. The synthesized multilayer GBR was composed of two distinct layers. Poly l-lactic acid (PLA) incorporated with simvastatin (SIM) was designed as PLA/SIM layer to contact with a bone defect. In addition, the hydrophilic gelatin (GT) containing thymol (THY) was fabricated as GT/THY layer to contact connective tissue, potentially for bacterial gathering. Due to the different chemical nature and weak cohesion of the hydrophilic and hydrophobic layers, hybrid fibers made of PLA/SIM and GT/THY were electrospun as cohesion promoters between these layers. The microstructure and characteristics of the synthesized multilayer substrate, named GT/PLA, were evaluated, and different fibrous monolayers were fabricated to determine the optimal concentrations of drugs. Scanning electron microscopy (SEM) images showed continuous, smooth, randomly aligned, and bead-free fibers. In addition, there were no drug particles on the fiber surfaces which displayed the good placement of those inside the fibers. The mats exhibited satisfactory tensile strength (4.60 ± 0.14 MPa) and favorable physicochemical properties, including proper porosity percentage (<50 %) and appropriate pore size. Suitable swelling behavior (293 ± 0.05 %) and adequate degradation rates were also approved by characterizing swelling and degradability in vitro. The GT/PLA membrane exhibited a prolonged and sustained SIM release and controlled THY release with high antibacterial efficiency. Cell viability, cell attachment assay, and nuclear staining using 4',6-diamidino-2-phenylindole (DAPI) showed that the designed GT/PLA substrate had good biocompatibility and cell attachment. Cell infiltration testing also showed that the cells were finely prevented by the outer layer (GT/THY). Overall, the obtained results in this study indicated the great potential of the prepared GT/PLA for use as a GBR which can develop osteogenic and antibacterial biomimetic periosteum optimizing the clinical application of GBR strategies.

Recent Advances in Using Natural Antibacterial Additives in Bioactive Wound Dressings

Wound care is a global health issue with a financial burden of up to US $96.8 billion annually in the USA alone. Chronic non-healing wounds which show delayed and incomplete healing are especially problematic. Although there are more than 3000 dressing types in the wound management market, new developments in more efficient wound dressings will require innovative approaches such as embedding antibacterial additives into wound-dressing materials. The lack of novel antibacterial agents and the misuse of current antibiotics have caused an increase in antimicrobial resistance (AMR) which is estimated to cause 10 million deaths by 2050 worldwide. These ongoing challenges clearly indicate an urgent need for developing new antibacterial additives in wound dressings targeting microbial pathogens. Natural products and their derivatives have long been a significant source of pharmaceuticals against AMR. Scrutinising the data of newly approved drugs has identified plants as one of the biggest and most important sources in the development of novel antibacterial drugs. Some of the plant-based antibacterial additives, such as essential oils and plant extracts, have been previously used in wound dressings; however, there is another source of plant-derived antibacterial additives, i.e., those produced by symbiotic endophytic fungi, that show great potential in wound dressing applications. Endophytes represent a novel, natural, and sustainable source of bioactive compounds for therapeutic applications, including as efficient antibacterial additives for chronic wound dressings. This review examines and appraises recent developments in bioactive wound dressings that incorporate natural products as antibacterial agents as well as advances in endophyte research that show great potential in treating chronic wounds.

A Review of the Release Profiles and Efficacies of Chemotherapy Drug-Loaded Electrospun Membranes

Electrospun fibrous membranes loaded with chemotherapy drugs have been broadly studied, many of which have had promising data demonstrating therapeutic effects on cancer cell inhibition, tumor size reduction, the life extension of tumor-bearing animals, and more. Nevertheless, their drug release profiles are difficult to predict since their degradation pattern varies with crystalline polymers. In addition, there is room for improving their release performances, optimizing the release patterns, and achieving better therapeutic outcomes. In this review, the key factors affecting electrospun membrane drug release profiles have been systematically reviewed. Case studies of the release profiles of typical chemotherapy drugs are carried out to determine the preferred polymer choices and techniques to achieve the expected prolonged or enhanced release profiles. The therapeutic effects of these electrospun, chemo-drug-loaded membranes are also discussed. This review aims to assist in the design of future drug-loaded electrospun materials to achieve preferred release profiles with enhanced therapeutic efficacies.

New formulation of fermented sausages towards healthier and quality rectification by adding <em>Ferulago angulata</em> essential oil

The demand is improved for ready-to-eat meals by lifestyle changes and fermented sausages are popular meat products because of their flavor. Natural compositions are considered as substitutes of synthetic preservatives in products, which have been extensively employed. The aim of present research is to investigate the impact of Ferulago Angulata Essential Oil (FAEO) as an antimicrobial and antioxidant factor for preserving of dry fermented sausages throughout storage. Initially, FAEO was extracted using microwave assisted hydrodistillation and its components were identified by gas chromatography-mass spectroscopy. Fermented sausages were treated by starter culture (Biobak K) and FAEO at various concentrations (0, 400, 800 and 1000 ppm). Afterwards, tests such as pH, moisture, thiobarbituric acid, texture, microbial growth, electron microscope images, and sensory evaluation were conducted during storage (28 d). The high levels of bioactive compositions such as limonene (30.71%) and α-pinene (19.02%) were indicated in FAEO. The results illustrated that pH and moisture of all fermented sausages were within the standard range during storage. At different concentrations, FAEO significantly decreased thiobarbituric acid of treated samples compared to control (p<0.05). Furthermore, FAEO was able to improve cohesiveness and elasticity of fermented sausages, which were also visible in electron microscope images. Antimicrobial feature of FAEO was distinguished by evaluating microbial attributes (total viable count, lactic acid bacteria and yeast) in fermented sausages. Ultimately, FAEO at 800 ppm concentration was detected as a promising and appropriate natural preservative during storage in fermented sausages.

Evaluation of poly(N-isopropylacrylamide)/tetraphenylethylene/amphotericin B-based visualized antimicrobial nanofiber wound dressing for whole skin wound healing in rats

The aim of this work is to develop a novel nanofiber wound dressing with multiple functional properties that combines suitable mechanical properties, slow and controlled drug release, antifungal activity, and visual drug monitoring to accelerate wound healing while reducing systemic circulation of the drug, achieving reduced dose and side effects, and achieving patient satisfaction and compliance. In this paper, visualized nanofiber films were prepared using electrostatic spinning technology. This nanofiber wound dressing has soft tissue-like mechanical and antifungal properties and is biocompatible. In particular, the poly(N-isopropylacrylamide) (PNIPAAm)/tetraphenylethylene (TPE)/amphotericin B (AMB) nanofiber films showed good performance in terms of antifungal activity and cytocompatibility compared with medical gauze, and significantly accelerated the wound healing process in a mouse total wound defect model with PCL+PVP+TPE+AMB+PNIPAAm. The wound healing rate of nanofibrous membrane group was 100% at 14 days. In addition, histological analysis, collagen deposition and immunohistochemistry showed, for example, fewer inflammatory cells, more fibroblasts around the damaged area, increased wound epithelial atrophy, reduced granulation tissue, connective tissue reconstruction, epithelial tissue formation, and abundant small angiogenesis in the dermis near the epidermis; a higher level of collagen deposition fraction of 49.97%; and a simultaneous reduction in HIF-1α production and upregulated the expression of CD31. In conclusion, this antifungal nanofiber film showed promising applications throughout the skin wound healing process.

Nigella/honey/garlic/olive oil co-loaded PVA electrospun nanofibers for potential biomedical applications

The current work focuses on the formation of nanofibrous mats without the use of toxic solvents and metallic nanoparticles utilizing polyvinyl alcohol (PVA) and a blend of nigella, honey, garlic, and olive oil. Using deionized water (DI) water as a solvent, nanofibrous mats composed of PVA/nigella/honey (PNH) and PVA/garlic/honey/olive oil (PGHO) were developed. Methanol extraction was utilized to extract the therapeutic components of nigella sativa. Antibacterial and moisture management tests (MMT) were employed to examine the antibacterial and absorbance characteristics of the PNH and PGHO nanofibrous. Scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FTIR) tests were employed to analyze the morphological and chemical characteristics. PGHO showed thermal stability up to 245 °C, and PNH withstands until 225 °C. PNH and PGHO both exhibited antibacterial activity against Staphylococcus aureus (S. aureus), with inhibition zones of 36 mm and 35 mm, respectively. The synthesized materials exhibited excellent absorbance properties, thermal stability, cytotoxicity, and the production of thin nanofibers with an average diameter between 150 and 170 nm. The samples were characterized using FTIR spectra, which confirmed the presence of all components in the developed samples. To date, extensive research on electrospinning for biomedical applications has been undertaken using a variety of hazardous solvents and metallic nanoparticles. Briefly, our objective is to develop nanofibrous materials from plant extracts through a process called "green electrospinning" to observe the synergistic effect of multiple biocomponents incorporated nanofibers avoiding toxic solvents and metallic compounds for potential biomedical applications.

Removal of lead from aqueous solution using electrospun nanofibers: preparation, characterization, adsorption isotherm, and kinetic study

Lead is one of the most hazardous toxic heavy metal ions in industrial wastewater. The removal of Pb(II) from aqueous environment is an extremely essential topic due to acquiring clean water resources and its significant impact on human health. Adsorption is an effective and the most widely used method for heavy metal removal from an aqueous medium. Nanofibers have potential advantages in the adsorption of heavy metal ions from wastewater. In this study, nanofibers based on polyvinyl alcohol (PVA) were fabricated for the removal of lead ions from aqueous samples. Nanofibers produced by electrospinning were characterized by scanning electron microscopy (SEM/EDX) and Fourier transform infrared (FT-IR) techniques. A batch system was used for the adsorption of Pb(II) ions onto cross-linked PVA (%10) and PVA (%10):MSs (%2) (Malva Sylestris L. seed biomaterial) nanofibers. The effectiveness of cross-linking was determined by the water absorbency test. The pH, adsorbent amount, adsorption kinetics, isotherms, and thermodynamic values were thoroughly investigated in the adsorption tests. Pb(II) adsorption on the polymer was confirmed by EDX analysis. The optimum values found were a pH of 6, an adsorbent dose of 5.0 mg, and a contact time of 120 min. Lead ion concentrations were determined by flame atomic absorption spectrometry (FAAS). The Freundlich models could explain the results from the adsorption data. Similar results were obtained from adsorption isotherm models, and the results were found to support each other. The adsorption capacity for PVA (10%) and PVA (10%):MSs (2%) nanofibers were found to be 444.2 mg g^-1 and 588.2 mg g^-1, respectively. The adsorption capacity increases with the addition of MSs (2%) biomaterial. As a result, nanofibers can be used as effective adsorbents in the removal of Pb(II) ions. The developed methods are environmentally friendly and promising for the separation of toxic Pb(II) ions from aqueous systems, which is a major problem for environmental pollution.

Shape Memory Polymer Foams with Phenolic Acid-Based Antioxidant Properties

Phenolic acids (PAs) are natural antioxidant agents in the plant kingdom that are part of the human diet. The introduction of naturally occurring PAs into the network of synthetic shape memory polymer (SMP) polyurethane (PU) foams during foam fabrication can impart antioxidant properties to the resulting scaffolds. In previous work, PA-containing SMP foams were synthesized to provide materials that retained the desirable shape memory properties of SMP PU foams with additional antimicrobial properties that were derived from PAs. Here, we explore the impact of PA incorporation on SMP foam antioxidant properties. We investigated the antioxidant effects of PA-containing SMP foams in terms of in vitro oxidative degradation resistance and cellular antioxidant activity. The PA foams showed surprising variability; p-coumaric acid (PCA)-based SMP foams exhibited the most potent antioxidant properties in terms of slowing oxidative degradation in H₂O₂. However, PCA foams did not effectively reduce reactive oxygen species (ROS) in short-term cellular assays. Vanillic acid (VA)- and ferulic acid (FA)-based SMP foams slowed oxidative degradation in H₂O₂ to lesser extents than the PCA foams, but they demonstrated higher capabilities for scavenging ROS to alter cellular activity. All PA foams exhibited a continuous release of PAs over two weeks. Based on these results, we hypothesize that PAs must be released from SMP foams to provide adequate antioxidant properties; slower release may enable higher resistance to long-term oxidative degradation, and faster release may result in higher cellular antioxidant effects. Overall, PCA, VA, and FA foams provide a new tool for tuning oxidative degradation rates and extending potential foam lifetime in the wound. VA and FA foams induced cellular antioxidant activity that could help promote wound healing by scavenging ROS and protecting cells. This work could contribute a wound dressing material that safely releases antimicrobial and antioxidant PAs into the wound at a continuous rate to ideally improve healing outcomes. Furthermore, this methodology could be applied to other oxidatively degradable biomaterial systems to enhance control over degradation rates and to provide multifunctional scaffolds for healing.

Valorization of Aloe vera Skin By-Products to Obtain Bioactive Compounds by Microwave-Assisted Extraction: Antioxidant Activity and Chemical Composition

Aloe vera skin (AVS) is a major by-product of Aloe processing plants all over the world. In this study, response surface methodology was used to optimize microwave-assisted extraction (MAE) of bioactive compounds from AVS. The influence of extraction parameters, such as ethanol concentration (%Et), extraction temperature (T), time (t) and solvent volume (V), on extraction yield (Y), total phenolic content (TPC), antioxidant activity (DPPH and FRAP methods) and aloin content, was studied. Optimum extraction conditions were determined as 80% ethanol, 80 °C, 36.6 min and 50 mL and optimized extracts showed interesting contents of polyphenols and antioxidant performance. The phenolic profile was determined by HPLC-DAD/MS and some major phenolic compounds, such as aloin A, aloin B, aloesin, aloe-emodin, aloeresin D, orientin, cinnamic acid and chlorogenic acid, were quantified while eight other compounds were tentatively identified. Moreover, structural and thermal properties were studied by FTIR and TGA analyses, respectively. The obtained results suggested the potential of AVS as a promising source of bioactive compounds, thus increasing the added value of this agricultural waste.

The Potential of α-Mangostin from Garcinia mangostana as an Effective Antimicrobial Agent-A Systematic Review and Meta-Analysis

This systematic review aims to evaluate the antimicrobial activity of α-mangostin derived from Garcinia mangostana against different microbes. A literature search was performed using PubMed and Science Direct until March 2022. The research question was developed based on a PICO (Population, Intervention, Control and Outcomes) model. In this study, the population of interest was microbes, α-mangostin extracted from Garcinia mangostana was used as exposure while antibiotics were used as control, followed by the outcome which is determined by the antimicrobial activity of α-mangostin against studied microbes. Two reviewers independently performed the comprehensive literature search following the predetermined inclusion and exclusion criteria. A methodological quality assessment was carried out using a scoring protocol and the risk of bias in the studies was analyzed. Reward screening was performed among the selected articles to perform a meta-analysis based on the pre-determined criteria. Case groups where α-mangostin extracted from Garcinia mangostana was incorporated were compared to groups using different antibiotics or antiseptic agents (control) to evaluate their effectiveness. A total of 30 studies were included; they were heterogeneous in their study design and the risk of bias was moderate. The results showed a reduction in microbial counts after the incorporation of α-mangostin, which resulted in better disinfection and effectiveness against multiple microbes. Additionally, the meta-analysis result revealed no significant difference (p > 0.05) in their effectiveness when α-mangostin was compared to commercially available antibiotics. α-mangostin worked effectively against the tested microbes and was shown to have inhibitory effects on microbes with antibiotic resistance.

Nanofiber Systems as Herbal Bioactive Compounds Carriers: Current Applications in Healthcare

Nanofibers have emerged as a potential novel platform due to their physicochemical properties for healthcare applications. Nanofibers’ advantages rely on their high specific surface-area-to-volume and highly porous mesh. Their peculiar assembly allows cell accommodation, nutrient infiltration, gas exchange, waste excretion, high drug release rate, and stable structure. This review provided comprehensive information on the design and development of natural-based polymer nanofibers with the incorporation of herbal medicines for the treatment of common diseases and their in vivo studies. Natural and synthetic polymers have been widely used for the fabrication of nanofibers capable of mimicking extracellular matrix structure. Among them, natural polymers are preferred because of their biocompatibility, biodegradability, and similarity with extracellular matrix proteins. Herbal bioactive compounds from natural extracts have raised special interest due to their prominent beneficial properties in healthcare. Nanofiber properties allow these systems to serve as bioactive compound carriers to generate functional matrices with antimicrobial, anti-inflammatory, antioxidant, antiseptic, anti-viral, and other properties which have been studied in vitro and in vivo, mostly to prove their wound healing capacity and anti-inflammation properties.

----Evaluation of Design and Fabrication of Food-Grade Nanofibers from Chitosan-Gelatin for Nanoencapsulation of Stigmasterol Using the Electrospinning Method

Purpose: In this research, electrospinning method was employed to fabricate food-grade nanofibers (NFs) from chitosan-gelatin combination for stigmasterol encapsulation. The spinnability of mixed chitosan and gelatin solutions was investigated at different polymer ratios, and the physicochemical properties of the NFs were evaluated.

Methods: The mixture solution of chitosan (1.5 % w/v) and gelatin (20 % w/v) in acetic acid indicated spinnability under the following conditions: the ratio of 25:75, voltage of 17 kV, and 15 cm capillary collector distance with a flow rate of 0.2 mL/min. Stigmasterol (0.04 % w/v) was incorporated into NFs of chitosan-gelatin at a respective ratio of 25:75.

Results: Encapsulation efficiency (EE) of loaded stigmasterol was found to be 87 ± 5 %. The antioxidant ability of loaded stigmasterol was considerably higher than that observed for free stigmasterol. Scanning electron microscopy (SEM) results demonstrated the formation of the ultrathin fibers with no bead (with diameters of 217 ± 43 nm). The concentration of polymeric solution and viscosity had a notable effect on the electrospinning efficiency of the chitosan-gelatin-based NFs. The thermal stability of chitosan and gelatin fibers was more than that of native gelatin and chitosan. The in vitro stigmasterol release from these NFs followed a controlled-release pattern. The released phytosterol from chitosan formula was less than from those without chitosan formula (46 ± 3 % and 96 ± 4 % respectively).

Conclusion: The obtained results suggested that gelatin had a high potential for enhancing the spinnability of chitosan under acidic conditions at optimized concentrations.

Integrating Antioxidant Functionality into Polymer Materials: Fundamentals, Strategies, and Applications

While antioxidants are widely known as natural components of healthy food and drinks or as additives to commercial polymer materials to prevent their degradation, recent years have seen increasing interest in enhancing the antioxidant functionality of newly developed polymer materials and coatings. This paper provides a critical overview and comparative analysis of multiple ways of integrating antioxidants within diverse polymer materials, including bulk films, electrospun fibers, and self-assembled coatings. Polyphenolic antioxidant moieties with varied molecular architecture are in the focus of this Review, because of their abundance, nontoxic nature, and potent antioxidant activity. Polymer materials with integrated polyphenolic functionality offer opportunities and challenges that span from the fundamentals to their applications. In addition to the traditional blending of antioxidants with polymer materials, developments in surface grafting and assembly via noncovalent interaction for controlling localization versus migration of antioxidant molecules are discussed. The versatile chemistry of polyphenolic antioxidants offers numerous possibilities for programmed inclusion of these molecules in polymer materials using not only van der Waals interactions or covalent tethering to polymers, but also via their hydrogen-bonding assembly with neutral molecules. An understanding and rational use of interactions of polyphenol moieties with surrounding molecules can enable precise control of concentration and retention versus delivery rate of antioxidants in polymer materials that are critical in food packaging, biomedical, and environmental applications.

Perspective on the application of medicinal plants and natural products in wound healing: A mechanistic review

Wound is defined as any injury to the body such as damage to the epidermis of the skin and disturbance to its normal anatomy and function. Since ancient times, the importance of wound healing has been recognized, and many efforts have been made to develop novel wound dressings made of the best material for rapid and effective wound healing. Medicinal plants play a great role in the wound healing process. In recent decades, many studies have focused on the development of novel wound dressings that incorporate medicinal plant extracts or their purified active compounds, which are potential alternatives to conventional wound dressings. Several studies have also investigated the mechanism of action of various herbal medicines in wound healing process. This paper attempts to highlight and review the mechanistic perspective of wound healing mediated by plant-based natural products. The findings showed that herbal medicines act through multiple mechanisms and are involved in various stages of wound healing. Some herbal medicines increase the expression of vascular endothelial growth factor (VEGF) and transforming growth factor-β (TGF-β) which play important role in stimulation of re-epithelialization, angiogenesis, formation of granulation tissue, and collagen fiber deposition. Some other wound dressing containing herbal medicines act as inhibitor of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and inducible nitric oxide synthase (iNOS) protein expression thereby inducing antioxidant and anti-inflammatory properties in various phases of the wound healing process. Besides the growing public interest in traditional and alternative medicine, the use of herbal medicine and natural products for wound healing has many advantages over conventional medicines, including greater effectiveness due to diverse mechanisms of action, antibacterial activity, and safety in long-term wound dressing usage.

Reviewing Chitin/Chitosan Nanofibers and Associated Nanocomposites and Their Attained Medical Milestones

Chitin/chitosan research is an expanding field with wide scope within polymer research. This topic is highly inviting as chitin/chitosan's are natural biopolymers that can be recovered from food waste and hold high potentials for medical applications. This review gives a brief overview of the chitin/chitosan based nanomaterials, their preparation methods and their biomedical applications. Chitin nanofibers and Chitosan nanofibers have been reviewed, their fabrication methods presented and their biomedical applications summarized. The chitin/chitosan based nanocomposites have also been discussed. Chitin and chitosan nanofibers and their binary and ternary composites are represented by scattered superficial reports. Delving deep into synergistic approaches, bringing up novel chitin/chitosan nanocomposites, could help diligently deliver medical expectations. This review highlights such lacunae and further lapses in chitin related inputs towards medical applications. The grey areas and future outlook for aligning chitin/chitosan nanofiber research are outlined as research directions for the future.

Fast acting hemostatic agent based on self-assembled hybrid nanofibers from chitosan and casein

Hemorrhage is a leading cause of preventable death in both military combat and civilian accidents. To overcome these challenges, an affordable and effective bandage is must required substance. A novel strategy is reported for developing chitosan-casein (CC) based self-assembled nanofibrous polyelectrolyte complex (PEC) for rapid blood clotting. The amide group (1630 cm^-1) and phosphate group (910 cm^-1) of chitosan-casein can form PEC at pH 8.2 ± 0.2. The PECs contain intertwined nanofibers (≤100 nm diameter) with a high surface area. Increasing chitosan percentage from 30% (CC30) to 50% (CC50) or 70% (CC70) results, increase in zeta potential of PEC from -9.14 ± 3.3 to 7.46 ± 3.7 and 14.8 ± 3.3 mV, respectively. Under in vitro conditions, the CC30, CC50, and CC70 PECs allow platelet adhesion and rapidly absorbs blood fluid to form mechanically stable blood clots within 9 ± 3, 16 ± 3, and 30 ± 4 s, respectively, which are better than Celox™ (90 ± 3 s). In vivo application of PEC (CC50) causes clotting within 37 ± 6 s of large (1 cm) arterial incision in rabbit models. The PEC is biocompatible with promising hemostatic efficiency. This is the first report of nanofibrous PEC from chitosan and casein for rapid clotting, to the best of our knowledge.

Multifunctional cellulosic nanofiber film with enhanced antimicrobial and anticancer properties by incorporation of ethanolic extract of Garcinia mangostana peel

Natural polymeric nanofibers-based materials for medical application is an intensive research area due to the unique features of natural polymeric nanofibers. Bacterial nanocellulose (BC) films containing various concentrations of mangosteen (Garcinia mangostana) peel extract were prepared and evaluated as a multifunctional nanofiber film. The extract was absorbed into BC hydrogel and air dried to entrap the extract into nanofiber network. The resulting films contained about 3, 35, and 294 mg of total phenolic compounds and 2, 24, and 250 mg of α-mangostin per cm³ of the dried films. The film containing the highest phenolic compounds and α-mangostin performed the inhibitory effect to Staphylococcus epidermidis, Propionibacterium acnes, and Staphylococcus aureus. High anticancer activity against B16F10 melanoma and MCF-7 breast cancer cells having viabilities of 10 and 5%, respectively after 48 h were detected after the treatments with the film. However, the film had a low toxicity against normal fibroblast and keratinocyte cells with 41 and 99% viability, respectively. The research suggested that the prepared films were a multifunctional nanofiber films with antimicrobial and anticancer properties.

Nanotechnologies: An Innovative Tool to Release Natural Extracts with Antimicrobial Properties

Site-Specific release of active molecules with antimicrobial activity spurred the interest in the development of innovative polymeric nanocarriers. In the preparation of polymeric devices, nanotechnologies usually overcome the inconvenience frequently related to other synthetic strategies. High performing nanocarriers were synthesized using a wide range of starting polymer structures, with tailored features and great chemical versatility. Over the last decade, many antimicrobial substances originating from plants, herbs, and agro-food waste by-products were deeply investigated, significantly catching the interest of the scientific community. In this review, the most innovative strategies to synthesize nanodevices able to release antimicrobial natural extracts were discussed. In this regard, the properties and structure of the starting polymers, either synthetic or natural, as well as the antimicrobial activity of the biomolecules were deeply investigated, outlining the right combination able to inhibit pathogens in specific biological compartments.

The role of nanohydroxyapatite on the morphological, physical, and biological properties of chitosan nanofibers

OBJECTIVES

This study aimed to evaluate the effects of nanohydroxyapatite (nHAp) particles on the morphological, chemical, physical, and biological properties of chitosan electrospun nanofibers.

MATERIALS AND METHODS

nHAp particles with a 1.67 Ca/P ratio were synthesized via the aqueous precipitation method, incorporated into chitosan polymer solution (0.5 wt%), and electrospun into nHAp-loaded fibers (ChHa fibers). Neat chitosan fibers (nHAp-free, Ch fibers) were used as the control. The electrospun fiber mats were characterized using morphological, topographical, chemical, thermal, and a range of biological (antibacterial, antibiofilm, cell viability, and alkaline phosphatase [ALP] activity) analyses. Data were analyzed using ANOVA and Tukey's test (α = 0.05).

RESULTS

ChHa fibers demonstrated a bead-like morphology, with thinner (331 ± 110 nm) and smoother (Ra = 2.9 ± 0.3 μm) distribution as compared to the control fibers. Despite showing similar cell viability and ALP activity to Ch fibers, the ChHa fibers demonstrated greater antibacterial potential against most tested bacteria (except for P. intermedia), and higher antibiofilm activity against P. gingivalis biofilm.

CONCLUSIONS

The incorporation of nHAp particles did not jeopardize the overall morphology, topography, physical, and biological characteristics of the chitosan nanofibers.

CLINICAL RELEVANCE

The combination of nHAp particles with chitosan can be used to engineer bioactive, electrospun composite nanofibers with potential applications in regenerative dentistry.

Medicinal plants used in wound dressings made of electrospun nanofibers

Nanofibers are a type of nanostructures, which due to their unique properties can be used in wound dressing, and electrospinning is a good way to produce them. The benefits of wound dressings made of electrospun nanofibers include a large surface area to volume ratio, high absorption of secretions from the wound, and high air permeability, mimicking the morphology of extracellular matrix (ECM) of the damaged tissue and the possibility of the gradual release of the drug agents loaded on nanofibers. Because of the adaptability of plants to the body, low side effects and the prevalence of antibiotic resistance, interest in using plants is increasing. Combining nanofibers with plants is a way to integrate the physical properties of the structure of nanofibers and the chemical and antibacterial properties of the plants. In recent years, many plants in the forms of extracts, essential oils, and pure active ingredients have been used in the electrospininng and production of nanofiber-containing plants; some of the plants may be a good choice for wound dressings made of electrospun nanofibers.

Encapsulation of Bioactive Compounds from Aloe Vera Agrowastes in Electrospun Poly (Ethylene Oxide) Nanofibers

Aloe Vera is an ancient medicinal plant especially known for its beneficial properties for human health, due to its bioactive compounds. In this study, nanofibers with antioxidant activity were successfully obtained by electrospinning technique with the addition of a natural Aloe Vera skin extract (AVE) (at 0, 5, 10 and 20 wt% loadings) in poly(ethylene oxide) (PEO) solutions. The successful incorporation of AVE into PEO was evidenced by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (ATR-FTIR), thermogravimetric analysis (TGA) and antioxidant activity by 2,2-diphenyl-1-picrylhydrazyl radical scavenging (DPPH), 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging (ABTS) and ferric reducing power (FRAP) assays. The incorporation of AVE introduced some changes in the PEO/AVE nanofibers morphology showing bimodal diameter distributions for AVE contents in the range 10-20 wt%. Some decrease in thermal stability with AVE addition, in terms of decomposition onset temperature, was also observed and it was more evident at high loading AVE contents (10 and 20 wt%). High encapsulation efficiencies of 92%, 76% and 105% according to DPPH, FRAP and ABTS assays, respectively, were obtained at 5 wt% AVE content, retaining AVE its antioxidant capacity in the PEO/AVE electrospun nanofibers. The results suggested that the obtained nanofibers could be promising materials for their application in active food packaging to decrease oxidation of packaged food during storage.

Nanostructured Fibers Containing Natural or Synthetic Bioactive Compounds in Wound Dressing Applications

The interest in wound healing characteristics of bioactive constituents and therapeutic agents, especially natural compounds, is increasing because of their therapeutic properties, cost-effectiveness, and few adverse effects. Lately, nanocarriers as a drug delivery system have been actively investigated and applied in medical and therapeutic applications. In recent decades, researchers have investigated the incorporation of natural or synthetic substances into novel bioactive electrospun nanofibrous architectures produced by the electrospinning method for skin substitutes. Therefore, the development of nanotechnology in the area of dressings that could provide higher performance and a synergistic effect for wound healing is needed. Natural compounds with antimicrobial, antibacterial, and anti-inflammatory activity in combination with nanostructured fibers represent a future approach due to the increased wound healing process and regeneration of the lost tissue. This paper presents different approaches in producing electrospun nanofibers, highlighting the electrospinning process used in fabricating innovative wound dressings that are able to release natural and/or synthetic substances in a controlled way, thus enhancing the healing process.

Applications of Electrospun Nanofibers with Antioxidant Properties: A Review

Antioxidants can be encapsulated to enhance their solubility or bioavailability or to protect them from external factors. Electrospinning has proven to be an excellent option for applications in nanotechnology, as electrospun nanofibers can provide the necessary environment for antioxidant encapsulation. Forty-nine papers related to antioxidants loaded onto electrospun nanofibers were categorized and reviewed to identify applications and new trends. Medical and food fields were commonly proposed for the newly obtained composites. Among the polymers used as a matrix for the electrospinning process, synthetic poly (lactic acid) and polycaprolactone were the most widely used. In addition, natural compounds and extracts were identified as antioxidants that help to inhibit free radical and oxidative damage in tissues and foods. The most recurrent active compounds used were tannic acid (polyphenol), quercetin (flavonoid), curcumin (polyphenol), and vitamin B6 (pyridoxine). The incorporation of active compounds in nanofibers often improves their bioavailability, giving them increased stability, changing the mechanical properties of polymers, enhancing nanofiber biocompatibility, and offering novel properties for the required field. Although most of the polymers used were synthetic, natural polymers such as silk fibroin, chitosan, cellulose, pullulan, polyhydroxybutyrate, and zein have proven to be proper matrices for this purpose.

Pharmaceutical applications of electrospinning

Development of tailor-made pharmaceutical nanofibers has gained vital prominence due to ease of fabrication and versatility of electrospinning (ES). ES is one of the flexible and, wonderful strategies for the fabrication of nanofibers. ES unit comprises a supplier of high voltage current, a syringe (pump), spinneret and a metal plate collector. The obtained nanofibers are optimized by manipulating process and formulation variables Viz: polymer/drug resolution (viscosity, concentration, physical phenomenon, molecular mass) and the environmental conditions (humidity, temperature). The electrospun nanofibers can be used for loading of the drug, amorphization of a crystalline API and an increase in its physical storage stability. ES technique enables mixing of two or more API and may facilitate or inhibit the burst release of a drug, along with attainment of modified release. Additionally, nanofibers demonstrate a reduction in overall dose needed for the therapeutic activity, by improving dissolution and bioavailability of the drugs. The current review is an attempt to focus on ES method, the optimization parameters, and pharmaceutical applications of the electrospun nanofibers.