Hydrogels for the Delivery of Plant-Derived (Poly)Phenols

N-Hydroxyalkanamide Based Organo/hydrogels as Novel Scaffolds for pH-Dependent Metronidazole and Theophylline Release

The traditional delivery of metronidazole and theophylline presents challenges like bitter taste, variable absorption, and side effects. However, gel-based systems offer advantages including enhanced targeted drug delivery, minimized side effects, and improved patient compliance, effectively addressing these challenges. Consequently, a cost-effective synthesis of N-hydroxyalkanamide gelators with varying alkyl chain lengths was achieved in a single-step reaction procedure. These gelators formed self-assembled aggregates in DMSO/water solvent system, resulting in organo/hydrogels at a minimum gelation concentration of 1.5 % w/v. Subsequently, metronidazole and theophylline were encapsulated within the gel core and released through gel-to-sol transition triggered by pH variation at 37 °C, while maintaining the structural-activity relationship. UV-vis spectroscopy was employed to observe the drug release behavior. Furthermore, in vitro cytotoxicity assays revealed cytotoxic effects against A549 lung adenocarcinoma cells, indicating anti-proliferative activity against human lung cancer cells. Specifically, the gel containing theophylline (16HAD+Th) exhibited cytotoxicity on cancerous A549 cells with IC50 values of 19.23±0.6 μg/mL, followed by the gel containing metronidazole (16HAD+Mz) with IC50 values of 23.75±0.7 μg/mL. Moreover, the system demonstrated comparable antibacterial activity against both gram-negative (E. coli) and gram-positive bacteria (S. aureus).

Trends in polysaccharide-based hydrogels and their role in enhancing the bioavailability and bioactivity of phytocompounds

Over the years, polysaccharides such as chitosan, alginate, hyaluronic acid, k-carrageenan, xanthan gum, carboxymethyl cellulose, pectin, and starch, alone or in combination with proteins and/or synthetic polymers, have been used to engineer an extensive portfolio of hydrogels with remarkable features. The application of polysaccharide-based hydrogels has the potential to alleviate challenges related to bioavailability, solubility, stability, and targeted delivery of phytocompounds, contributing to the development of innovative and efficient drug delivery systems and functional food formulations. This review highlights the current knowledge acquired on the preparation, features and applications of polysaccharide/phytocompounds hydrogel-based hybrid systems in wound management, drug delivery, functional foods, and food industry. The structural, functional, and biological requirements of polysaccharides and phytocompounds on the overall performance of such hybrid systems, and their impact on the application domains are also discussed.

Bioactive Compounds from Medicinal Plants as Potential Adjuvants in the Treatment of Mild Acne Vulgaris

In recent years, there has been a growing interest in the use of medicinal plants and phytochemicals as potential treatments for acne vulgaris. This condition, characterized by chronic inflammation, predominantly affects adolescents and young adults. Conventional treatment typically targets the key factors contributing to its development: the proliferation of Cutibacterium acnes and the associated inflammation. However, these treatments often involve the use of potent drugs. As a result, the exploration of herbal medicine as a complementary approach has emerged as a promising strategy. By harnessing the therapeutic properties of medicinal plants and phytochemicals, it may be possible to address acne vulgaris while minimizing the reliance on strong drugs. This approach not only offers potential benefits for individuals seeking alternative treatments but also underscores the importance of natural remedies of plant origin in dermatological care. The primary aim of this study was to assess the antimicrobial, antioxidant, and anti-inflammatory properties of plants and their phytochemical constituents in the management of mild acne vulgaris. A comprehensive search of scientific databases was conducted from 2018 to September 2023. The findings of this review suggest that medicinal plants and their phytochemical components hold promise as treatments for mild acne vulgaris. However, it is crucial to note that further research employing high-quality evidence and standardized methodologies is essential to substantiate their efficacy and safety profiles.

Nanocarriers for natural polyphenol senotherapeutics

Senescence is a heterogenous and dynamic process in which various cell types undergo cell-cycle arrest due to cellular stressors. While senescence has been implicated in aging and many human pathologies, therapeutic interventions remain inadequate due to the absence of a comprehensive set of biomarkers in a context-dependent manner. Polyphenols have been investigated as senotherapeutics in both preclinical and clinical settings. However, their use is hindered by limited stability, toxicity, modest bioavailability, and often inadequate concentration at target sites. To address these limitations, nanocarriers such as polymer nanoparticles and lipid vesicles can be utilized to enhance the efficacy of senolytic polyphenols. Focusing on widely studied senolytic agents-specifically fisetin, quercetin, and resveratrol-we provide concise summaries of their physical and chemical properties, along with an overview of preclinical and clinical findings. We also highlight common signaling pathways and potential toxicities associated with these agents. Addressing challenges linked to nanocarriers, we present examples of senotherapeutic delivery to various cell types, both with and without nanocarriers. Finally, continued research and development of senolytic agents and nanocarriers are encouraged to reduce the undesirable effects of senescence on different cell types and organs. This review underscores the need for establishing reliable sets of senescence biomarkers that could assist in evaluating the effectiveness of current and future senotherapeutic candidates and nanocarriers.

Nanoparticles incorporated hydrogels for delivery of antimicrobial agents: developments and trends

The prevention and treatment of microbial infections is an imminent global public health concern due to the poor antimicrobial performance of the existing antimicrobial regime and rapidly emerging antibiotic resistance in pathogenic microbes. In order to overcome these problems and effectively control bacterial infections, various new treatment modalities have been identified. To attempt this, various micro- and macro-molecular antimicrobial agents that function by microbial membrane disruption have been developed with improved antimicrobial activity and lesser resistance. Antimicrobial nanoparticle-hydrogels systems comprising antimicrobial agents (antibiotics, biological extracts, and antimicrobial peptides) loaded nanoparticles or antimicrobial nanoparticles (metal or metal oxide) constitute an important class of biomaterials for the prevention and treatment of infections. Hydrogels that incorporate nanoparticles can offer an effective strategy for delivering antimicrobial agents (or nanoparticles) in a controlled, sustained, and targeted manner. In this review, we have described an overview of recent advancements in nanoparticle-hydrogel hybrid systems for antimicrobial agent delivery. Firstly, we have provided an overview of the nanoparticle hydrogel system and discussed various advantages of these systems in biomedical and pharmaceutical applications. Thereafter, different hybrid hydrogel systems encapsulating antibacterial metal/metal oxide nanoparticles, polymeric nanoparticles, antibiotics, biological extracts, and antimicrobial peptides for controlling infections have been reviewed in detail. Finally, the challenges and future prospects of nanoparticle-hydrogel systems have been discussed.

Hydrogel-mediated delivery of platelet-derived exosomes: Innovations in tissue engineering

In this scholarly review, we conduct a thorough examination of the significant role played by platelet-derived exosomes (Plt-Exos) and hydrogels in the fields of tissue engineering and regenerative medicine. Our detailed investigation highlights the central involvement of Plt-Exos in various physiological and pathological processes, underscoring their potential contributions to diverse areas such as wound healing, neural rejuvenation, and cancer progression. Despite the promising therapeutic aspects, the notable variability in the isolation and characterization of pEVs underscores the need for a more rigorous and standardized methodology. Shifting our focus to hydrogels, they have emerged as promising biomaterials relevant to tissue engineering and regenerative medicine. Their unique characteristics, especially their chemical and physical adaptability, along with the modifiability of their biochemical properties, make hydrogels a captivating subject. These exceptional features open avenues for numerous tissue engineering applications, facilitating the delivery of essential growth factors, cytokines, and microRNAs. This analysis explores the innovative integration of Plt-Exos with hydrogels, presenting a novel paradigm in tissue engineering. Through the incorporation of Plt-Exos into hydrogels, there exists an opportunity to enhance tissue regeneration endeavors by combining the bioactive features of Plt-Exos with the restorative capabilities of hydrogel frameworks. In conclusion, the cooperative interaction between platelet-derived exosomes and hydrogels indicates a promising path in tissue engineering and regenerative medicine. Nevertheless, the successful execution of this approach requires a deep understanding of molecular dynamics, coupled with a dedication to refining isolation techniques.

Fabrication and Characterization of Taro (Colocasia esculenta)-Mucilage-Based Nanohydrogel for Shelf-Life Extension of Fresh-Cut Apples

Taro mucilage is a cost-effective, eco-friendly, and water-soluble edible viscous polysaccharide, which possesses diverse techno-functional properties including gelling and anti-microbial. Therefore, the objective of this study was to formulate and evaluate the efficacy of taro mucilage nanohydrogel for the shelf-life enhancement of fresh-cut apples. Taro mucilage was extracted using cold water extraction, and the yield of mucilage was found to be 2.95 ± 0.35% on a dry basis. Different concentrations of mucilage (1, 2, 3, 4, and 5%) were used to formulate the nanohydrogel. A smaller droplet size of 175.61 ± 0.92 nm was observed at 3% mucilage, with a zeta potential of -30.25 ± 0.94 mV. Moreover, FTIR data of nanohydrogel revealed the functional groups of various sugars, uronic acids, and proteins. Thermal analysis of nanohydrogel exhibited weight loss in three phases, and maximum weight loss occurred from 110.25 °C to 324.27 °C (65.16%). Nanohydrogel showed shear-thinning fluid or pseudo-plastic behavior. Coating treatment of nanohydrogel significantly reduced the weight loss of fresh-cut apples (8.72 ± 0.46%) as compared to the control sample (12.25 ± 0.78%) on the 10th day. In addition, minor changes were observed in the pH for both samples during the 10 days of storage. Titrable acidity of control fresh-cut apples measured 0.22 ± 0.05% on day 0, rising to 0.42 ± 0.03% on the 10th day, and for coated fresh-cut apples, it was observed to be 0.24 ± 0.07% on the 0th day and 0.36 ± 0.06% on 10th day, respectively. Furthermore, the total soluble solids (TSS) content of both control and coated fresh-cut apples measured on the 0th day was 11.85 ± 0.65% and 12.33 ± 0.92%, respectively. On the 10th day, these values were significantly increased (p < 0.05) to 16.38 ± 0.42% for the control and 14.26 ± 0.39% for the coated sliced apples, respectively. Nanohydrogel-coated fresh-cut apples retained antioxidant activity and vitamin C content as compared to the control sample. Taro mucilage nanohydrogel-based edible coating showed distinct anti-microbial activity against psychrotrophic, aerobic, and yeast molds. In summary, taro mucilage nanohydrogel can be used as a cost-effective natural coating material for the shelf-life enhancement or freshness maintenance of fresh-cut apples.

Evaluation of the Biological Activity of Hydrogel with Cornus mas L. Extract and Its Potential Use in Dermatology and Cosmetology

Due to the growing popularity of herbal extract-loaded hydrogels, this study assessed the biological activity of extracts and hydrogels containing three types (water (WE), water-ethanol (EE) and water-glycerin (GE)) of Cornus mas L. (dogwood) extracts. The content of biologically active compounds in the extracts was assessed using the UPLC-DAD-MS technique. Antioxidant properties were assessed by using DPPH and ABTS radicals and measuring the intracellular level of reactive oxygen species. Alamar Blue and Neutral Red tests were used to measure the cytotoxicity of the tested samples on skin cells-fibroblasts and keratinocytes. Cell migration and the anti-aging activity of the tested extracts and hydrogels were assessed. Transepidermal water loss and skin hydration after applying the hydrogels to the skin were also determined. A chromatographic analysis revealed that the extracts contained polyphenols, including gallic, caftaric, protocatechuic, chlorogenic, ellagic and p-coumaroylquinic acids, as well as iridoids, with loganic acid as the predominant component. Additionally, they contained cyanidin 3-O-galactoside, pelargonidin 3-O-glucoside and quinic acid. The obtained results show that the tested extracts and hydrogels had strong antioxidant properties and had a positive effect on the viability of skin cells in vitro. Additionally, it was shown that they stimulated the migration of these cells and had the ability to inhibit the activity of collagenase and elastase. Moreover, the tested hydrogels increased skin hydration and prevented transepidermal water loss. The obtained results indicate that the developed hydrogels may be effective delivery systems for phytochemicals contained in dogwood extracts.

Investigating the Effect of the Crosslinking Factor on the Properties of Hydrogel Materials Containing Tilia platyphyllos Hydrolate

The use of natural ingredients in recent years has been of great importance in many industries and medicine. In biomedical applications, hydrogel materials also play a significant role. In view of this, the aim of this study was to synthesize and characterize hydrogel materials enriched with broadleaf linden hydrolate. An important aspect was to carry out a series of syntheses with varying types and amounts of crosslinking agents so as to test the possibility of synthesizing materials with controlled properties. The obtained hydrogels were subjected to detailed physicochemical analysis. The results of the tests confirmed the relationship between the selected properties and the type of crosslinking agent used. A crosslinking agent with a lower molar mass (575 g/mol) results in a material with a compact and strongly crosslinked structure, which is characterized by high surface roughness. The use of a crosslinking agent with a molecular weight of 700 g/mol resulted in a material with a looser-packed polymer network capable of absorbing larger amounts of liquids. The work also proved that regardless of the type of crosslinking agent used, the addition of linden hydrolate provides antioxidant properties, which is particularly important in view of the target biomedical application of such materials.

Polysaccharide-Based Coatings as Drug Delivery Systems

Therapeutic polysaccharide-based coatings have recently emerged as versatile strategies to transform a conventional medical implant into a drug delivery system. However, the translation of these polysaccharide-based coatings into the clinic as drug delivery systems still requires a deeper understanding of their drug degradation/release profiles. This claim is supported by little or no data. In this review paper, a comprehensive description of the benefits and challenges generated by the polysaccharide-based coatings is provided. Moreover, the latest advances made towards the application of the most important representative coatings based on polysaccharide types for drug delivery are debated. Furthermore, suggestions/recommendations for future research to speed up the transition of polysaccharide-based drug delivery systems from the laboratory testing to clinical applications are given.

Application of polyvinyl alcohol/chitosan copolymer hydrogels in biomedicine: A review

Hydrogels is a hydrophilic, cross-linked polymer of three-dimensional network structures. The application of hydrogels prepared from a single polymer in the biomedical field has many drawbacks. The functional blend of polyvinyl alcohol and chitosan allows hydrogels to have better and more desirable properties than those produced from a single polymer, which is a good biomaterial for development and design. In this paper, we have reviewed the progress in the application of polyvinyl alcohol/chitosan composite hydrogels in various medical fields, the different cross-linking agents and cross-linking methods, and the research progress in the optimization of composite hydrogels for their subsequent wide range of biomedical applications.

Antimicrobial Natural Hydrogels in Biomedicine: Properties, Applications, and Challenges-A Concise Review

Natural hydrogels are widely used as biomedical materials in many areas, including drug delivery, tissue scaffolds, and particularly wound dressings, where they can act as an antimicrobial factor lowering the risk of microbial infections, which are serious health problems, especially with respect to wound healing. In this review article, a number of promising strategies in the development of hydrogels with biocidal properties, particularly those originating from natural polymers, are briefly summarized and concisely discussed. Common strategies to design and fabricate hydrogels with intrinsic or stimuli-triggered antibacterial activity are exemplified, and the mechanisms lying behind these properties are also discussed. Finally, practical antibacterial applications are also considered while discussing the current challenges and perspectives.

"Novel chitosan/alginate hydrogels as carriers of phenolic-enriched extracts from saffron floral by-products using natural deep eutectic solvents as green extraction media"

The current saffron production system is generating several hundreds of tons of tepal waste, because only stigmas are used for food. Consequently, the valorization of saffron floral by-products by developing stable functional ingredients could lead to the environmental impact minimization. Thus, the main aim of this study was to develop innovative green extraction processes from saffron floral by-products by using Natural Deep Eutectic Solvents (NaDES) and ultrasound-assisted extraction (UAE) as ecological extraction method. Response surface methodology was used to optimize process parameters. To improve the stability of the optimal extracts, they were incorporated into chitosan/alginate hydrogels, studying their water-uptake and water retention capacity and the total phenolic content (TPC) during the in vitro digestion. The results indicated that the optimal extraction, regarding total phenolic and flavonoid content, was achieved in 20 min, using 180 W ultrasound power and 90% of NaDES. The results of the DPPH assay revealed the potent antioxidant activity of saffron floral by-products. The chitosan/alginate hydrogels incorporating the as-obtained NaDES extracts showed favorable properties whereas the TPC remained stable under intestinal conditions. Therefore, NaDES combined with UAE was an efficient technique to isolate high added-value compounds from saffron flowers, succeeding also the valorization of discarded waste by using green and low-cost strategies. Furthermore, these novel hydrogels could be used as promising candidates for food or cosmetic applications.

Evaluation of Chokeberry/Carboxymethylcellulose Hydrogels with the Addition of Disaccharides: DART-TOF/MS and HPLC-DAD Analysis

With the growing awareness of the importance of a healthy diet, the need for the development of novel formulations is also on the rise. Chokeberry products are popular among consumers since they are a rich source of polyphenols that are responsible for antioxidant activity and other positive effects on human health. However, other natural food ingredients, such as disaccharides, can affect their stability. The aim of this study was to investigate the influence of disaccharides addition on the polyphenol composition of chokeberry hydrogels. Hydrogels were prepared from chokeberry juice and 2% of carboxymethylcellulose (CMC) with the addition of 30%, 40%, or 50% of disaccharides (sucrose or trehalose). Samples were analyzed using DART-TOF/MS. The method was optimized, and the fingerprints of the mass spectra have been statistically processed using PCA analysis. Prepared samples were evaluated for total polyphenols, monomeric anthocyanins, and antioxidant activity (FRAP, CUPRAC, DPPH, ABTS assays) using spectrophotometric methods. Individual polyphenols were evaluated using HPLC-DAD analysis. Results showed the addition of disaccharides to 2% CMC hydrogels caused a decrease of total polyphenols. These findings confirm proper formulation is important to achieve appropriate retention of polyphenols.

Hydrogels as promising carriers for the delivery of food bioactive ingredients

The burden of public health challenges associated with the western dietary and living style is growing. Nutraceuticals have been paid increasing attentions due to their effects in promotion of health. However, in the gastrointestinal (GI) tract, the nutraceuticals suffer from not only the harsh acidic environment of the stomach and a variety of digestive enzymes, but also the antibacterial activity of intestinal bile salts and the action of protease from the gut microbiota. The amount of the nutraceuticals arriving at the sites in GI tract for absorption or exerting the bioactivities is always unfortunately limited, which puts forward high requirements for protection of nutraceuticals in a certain high contents during oral consumption. Hydrogels are three-dimensional polymeric porous networks formed by the cross-linking of polymer chains, which can hold huge amounts of water. Compared with other carries with the size in microscopic scale such as nanoparticle and microcapsules, hydrogels could be considered to be more suitable delivery systems in food due to their macroscopic bulk properties, adjustable viscoelasticity and large spatial structure for embedding nutraceuticals. Regarding to the applications in food, natural polymer-based hydrogels are commonly safe and popular due to their source with the appealing characteristics of affordability, biodegradability and biocompatibility. Although chemical crosslinking has been widely utilized in preparation of hydrogels, it prefers the physical crosslinking in the researches in food. The reasonable design for the structure of natural polymeric hydrogels is essential for seeking the favorable functionalities to apply in the delivery system, and it could be possible to obtain the enhanced adhesive property, acid stability, resistant to bile salt, and the controlled release behavior. The hydrogels prepared with proteins, polysaccharides or the mix of them to deliver the functional ingredients, mainly the phenolic components, vitamins, probiotics are discussed to obtain inspiration for the wide applications in delivery systems. Further efforts might be made in the in situ formation of hydrogels in GI tract through the interaction among food polymers and small-molecular ingredients, elevation of the loading contents of nutraceuticals in hydrogels, development of stomach adhesive hydrogels as well as targeting modification of gut microbiota by the hydrogels.

Naringin-loaded Arabic gum/pectin hydrogel as a potential wound healing material

Wound healing is a complicated cellular process with overlapping phases. Naringin (NAR); a flavanone glycoside, possesses numerous pharmacological effects such as anti-inflammatory, antioxidant and anti-apoptotic effects. In the current study, Arabic gum (AG)/pectin hydrogel was utilized to encapsulate NAR. Drug-loaded AG/pectin hydrogel exhibited excellent EE% of about 99.88 ± 0.096 and high DL% of about 16.64 ± 0.013. The formulated drug-loaded hydrogel was characterized using Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and Zetasizer analyzer, besides determination of equilibrium degree of swelling (EDS%). Afterwards, wound healing potential of NAR-loaded AG/pectin hydrogel was evaluated in an in vivo animal model. Results manifested that NAR-loaded AG/pectin hydrogel was able to accelerate wound healing in terms of enhanced angiogenesis, re-epithelialization and collagen deposition. Furthermore, it significantly (P < 0.001) down-regulated the mRNA expression of inflammatory mediators (TNF-α) and apoptosis (BAX). In addition, NAR-loaded AG/pectin hydrogel was found to possess potent antioxidant activity as it enhanced the levels of SOD and GSH, besides decreasing the levels of MPO, MDA and nitrite. These data suggest that NAR-loaded AG/pectin hydrogel could be utilized in wound healing applications.

Silver Nanoparticles Formulation of Flower Head’s Polyphenols of Cynara scolymus L.: A Promising Candidate against Prostate (PC-3) Cancer Cell Line through Apoptosis Activation

Cynara scolymus L. (Family: Compositae) or artichoke is a nutritious edible plant widely used for its hepatoprotective effect. Crude extracts of flower, bract, and stem were prepared and evaluated for their in vitro antioxidant activity and phenolic content. The flower crude extract exhibited the highest phenolic content (74.29 mg GAE/gm) as well as the best in vitro antioxidant activity using total antioxidant capacity (TAC), ferric reducing antioxidant power (FEAP), and 1,1-diphenyl-2-picrylhyazyl (DPPH) scavenging assays compared with ascorbic acid. Phenolic fractions of the crude extracts of different parts were separated and identified using high-performance liquid chromatography HPLC-DAD analysis. The silver nanoparticles of these phenolic fractions were established and tested for their cytotoxicity and apoptotic activity. Results showed that silver nanoparticles of a polyphenolic fraction of flower extract (Nano-TP/Flowers) exhibited potent cytotoxicity against prostate (PC-3) and lung (A549) cancer cell lines with IC₅₀ values of 0.85 μg/mL and 0.94 μg/mL, respectively, compared with doxorubicin as a standard. For apoptosis-induction, Nano-TP/Flowers exhibited apoptosis in PC-3 with a higher ratio than in A549 cells. It induced total prostate apoptotic cell death by 227-fold change while it induced apoptosis in A549 cells by 15.6-fold change. Nano-TP/Flowers upregulated both pro-apoptotic markers and downregulated the antiapoptotic genes using RT-PCR. Hence, this extract may serve as a promising source for anti-prostate cancer candidates.

Novel Gels: An Emerging Approach for Delivering of Therapeutic Molecules and Recent Trends

Gels are semisolid, homogeneous systems with continuous or discrete therapeutic molecules in a suitable lipophilic or hydrophilic three-dimensional network base. Innovative gel systems possess multipurpose applications in cosmetics, food, pharmaceuticals, biotechnology, and so forth. Formulating a gel-based delivery system is simple and the delivery system enables the release of loaded therapeutic molecules. Furthermore, it facilitates the delivery of molecules via various routes as these gel-based systems offer proximal surface contact between a loaded therapeutic molecule and an absorption site. In the past decade, researchers have potentially explored and established a significant understanding of gel-based delivery systems for drug delivery. Subsequently, they have enabled the prospects of developing novel gel-based systems that illicit drug release by specific biological or external stimuli, such as temperature, pH, enzymes, ultrasound, antigens, etc. These systems are considered smart gels for their broad applications. This review reflects the significant role of advanced gel-based delivery systems for various therapeutic benefits. This detailed discussion is focused on strategies for the formulation of different novel gel-based systems, as well as it highlights the current research trends of these systems and patented technologies.

3D Chitosan-Gallic Acid Complexes: Assessment of the Chemical and Biological Properties

Three-dimensional chitosan-gallic acid complexes were proposed and prepared for the first time by a simple adsorption process of gallic acid (GA) on three-dimensional chitosan structures (3D chitosan). Highly porous 3D devices facilitate a high GA load, up to 2015 mmol/kg at pH 4.0. The preservation of the redox state of GA released from 3D chitosan was confirmed by spectroscopic analyses. The antioxidant activity of 3D chitosan-GA complexes was assessed using the DPPH radical scavenging assay and was found to be dramatically higher than that of free chitosan. The mechanical property of 3D chitosan–GA complexes was also evaluated using a compression test. Finally, 3D chitosan–GA complexes showed a significant antimicrobial capacity against E. coli and S. aureus, selected, respectively, as a model strain for Gram-negative and Gram-positive bacteria. Our study demonstrated a new, simple, and eco-friendly approach to prepare functional chitosan-based complexes for nutraceutical, cosmeceutical, and pharmaceutical applications.

Physicochemical Characteristics of Chitosan-Based Hydrogels Modified with Equisetum arvense L. (Horsetail) Extract in View of Their Usefulness as Innovative Dressing Materials

This work focused on obtaining and characterizing hydrogels with their potential application as dressing materials for chronic wounds. The research included synthesizing chitosan-based hydrogels modified with Equisetum arvense L. (horsetail) extract via photopolymerization, and their characteristics determined with regard to the impact of both the modifier and the amount of crosslinker on their properties. The investigations included determining their sorption properties and tensile strength, evaluating their behavior in simulated physiological liquids, and characterizing their wettability and surface morphology. The release profile of horsetail extract from polymer matrices in acidic and alkaline environments was also verified. It was proved that hydrogels showed swelling ability while the modified hydrogels swelled slightly more. Hydrogels showed hydrophilic nature (all contact angles were <77°). Materials containing horsetail extract exhibited bigger elasticity than unmodified polymers (even by 30%). It was proved that the extract release was twice as effective in an acidic medium. Due to the possibility of preparation of hydrogels with specific mechanical properties (depending on both the modifier and the amount of crosslinker used), wound exudate sorption ability, and possibility of the release of active substance, hydrogels show a great application potential as dressing materials.

Natural Product-Based Hybrids as Potential Candidates for the Treatment of Cancer: Focus on Curcumin and Resveratrol

One of the main current strategies for cancer treatment is represented by combination chemotherapy. More recently, this strategy shifted to the "hybrid strategy", namely the designing of a new molecular entity containing two or more biologically active molecules and having superior features compared with the individual components. Moreover, the term "hybrid" has further extended to innovative drug delivery systems based on biocompatible nanomaterials and able to deliver one or more drugs to specific tissues or cells. At the same time, there is an increased interest in plant-derived polyphenols used as antitumoral drugs. The present review reports the most recent and intriguing research advances in the development of hybrids based on the polyphenols curcumin and resveratrol, which are known to act as multifunctional agents. We focused on two issues that are particularly interesting for the innovative chemical strategy involved in their development. On one hand, the pharmacophoric groups of these compounds have been used for the synthesis of new hybrid molecules. On the other hand, these polyphenols have been introduced into hybrid nanomaterials based on gold nanoparticles, which have many potential applications for both drug delivery and theranostics in chemotherapy.

Hydrogels: Characteristics and Application as Delivery Systems of Phenolic and Aroma Compounds

Complex challenges are facing the food industry as it develops novel and innovative products for the consumer marketplace. Food processing and preservation are primarily based on achievement and maintenance of safety in order to protect consumers, as well as extending product shelf life under the relevant conditions of storage, transport and distribution. Maximizing retention of bioactives with recognized positive effects on health typically comes under consideration when the previous two priorities have been achieved. This review introduces the potential applications of hydrogels as delivery systems of high-value bioactives like phenolics and aromas. If they are successfully encapsulated within the gel structures, their release can be controlled, which opens a wide range of applications, not only in food, but also in the pharmaceutical and cosmetic industries. Hydrogels are three-dimensional network structures which can absorb significant amounts of water. They have the ability to thicken the system and therefore can be used to design products with desired properties. In order to preserve the valuable components, it is necessary to know their physicochemical properties, in addition to the properties of the polymer used for hydrogel preparation.