Chitosan/Virgin Coconut Oil-Based Emulsions Doped with Photosensitive Curcumin Loaded Capsules: A Functional Carrier to Topical Treatment.

In recent years, there has been a growing interest in developing smart drug delivery systems based on natural resources combined with stimulus-sensitive elements. This trend aims to formulate innovative and sustainable delivery platforms tailored for topical applications. This work proposed the use of layer-by-layer (LbL) methodology to fabricate biocompatible photo-responsive multilayer systems. These systems are composed of a polyoxometalate inorganic salt (POM) ([NaP5W30O110]14-) and a natural origin polymer, chitosan (CHT). Curcumin (CUR), a natural bioactive compound, was incorporated to enhance the functionality of these systems during the formation of hollow capsules. The capsules produced, with sizes between 2-5µm (SEM), were further dispersed into CHT/VCO (virgin coconut oil) emulsion solutions that were casted into molds and dried at 37 °C for 48 h. The system presented a higher water uptake in PBS than in acidic conditions, still significantly lower than that earlier reported to other CHT/VCO-based systems. The drug release profile is not significantly influenced by the medium pH reaching a maximum of 37% ± 1% after 48 h. The antioxidant performance of the designed structures was further studied, suggesting a synergistic beneficial effect resulting from CUR, POM, and VCO individual bioactivities. The increased amount of those excipients released to the media over time promoted an increase in the antioxidant activity of the system, reaching a maximum of 38.1% ± 0.1% after 48 h. This work represents a promising step towards developing advanced, sustainable drug delivery systems for topical applications.

Antimicrobial and antibiofilm properties of selenium-chitosan-loaded salicylic acid nanoparticles for the removal of emerging contaminants from bacterial pathogens.

In this study salicylic acid loaded containing selenium nanoparticles was synthesized and called SA@CS-Se NPs. the chitosan was used as a natural stabilizer during the synthesis process. Fourier transforms infrared spectroscopy (FTIR), Powder X-ray diffraction (XRD), field emission electron microscopy (FESEM), and transmission electron microscopy (TEM) were used to describe the physicochemical characteristics of the SA@CS-Se NPs. The PXRD examination revealed that the grain size was around 31.9 nm. TEM and FESEM techniques showed the spherical shape of SA@CS-Se NPs. Additionally, the analysis of experiments showed that SA@CS-Se NPs have antibacterial properties against 4 ATCC bacteria; So that with concentrations of 75, 125, 150, and 100 µg/ml, it inhibited the biofilm formation of Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, and Staphylococcus aureus respectively. Also, at the concentration of 300 µg/ml, it removed 22.76, 23.2, 10.62, and 18.08% biofilm caused by E. coli, P. aeruginosa, B. subtilis, and S. aureus respectively. The synthesized SA@CS-Se NPs may find an application to reduce the unsafe influence of pathogenic microbes and, hence, eliminate microbial contamination.

Recent advances in cellulose, pectin, carrageenan and alginate-based oral drug delivery systems.

Polymers-based drug delivery systems constitute one of the highly explored thrust areas in the field of the medicinal and pharmaceutical industries. In the past years, the properties of polymers have been modified in context to their solubility, release kinetics, targeted action site, absorption, and therapeutic efficacy. Despite the availability of diverse synthetic polymers for the bioavailability enhancement of drugs, the use of natural polymers is still highly recommended due to their easy availability, accessibility, and non-toxicity. The aim of the review is to provide the available literature of the last five years on oral drug delivery systems based on four natural polymers i.e., cellulose, pectin, carrageenan, and alginate in a concise and tabulated manner. In this review, most of the information is in tabulated form to provide easy accessibility to the reader. The data related to active pharmaceutical ingredients and supported components in different formulations of the mentioned polymers have been made available.

Different Types of Naturally based Drug Delivery Carriers: An Explanation and Expression of Some Anti-cancer Effects.

Cancer remains one of the leading causes of death worldwide and a major impediment to increasing life expectancy. However, survival rates with average standard cancer treatment strategies have not significantly improved in recent decades, with tumor metastasis, adverse drug reactions, and drug resistance still posing major challenges. Replacement therapies are essential for treating this terrible disease. Recently, there has been a dramatic increase in the use of phytochemical-derived conjugated chemotherapeutic agents due to their biocompatibility, low cytotoxicity, low resistance, and dynamic physiochemical properties that distinguish normal cells in treating various types of cancer. The use of plant-based carriers has many advantages, such as the availability of raw materials, lower cost, lower toxicity in most cases, and greater compatibility with the body's structure compared to chemical and mineral types of carriers. Unfortunately, several challenges complicate the efficient administration of herbal medicines, including physicochemical disadvantages such as poor solubility and instability, and pharmacokinetic challenges such as poor absorption and low bioavailability that can cause problems in clinical trials. Novel delivery systems such as liposomes, phytosomes, nanoparticles, and nanocapsules are more suitable as delivery systems for phytomedicinal components compared to conventional systems. The use of these delivery systems can improve bioavailability, pharmacological activity, prolonged delivery, and provide physical and chemical stability that increases half-life. This article discusses different types of phytocompounds used in cancer treatment.

Differential binding of piperine & curcumin with modified cellulose, alginate and pectin supports: In-vitro & in-silico studies.

Use of natural polymer in the development of Drug Delivery Systems (DDS) has greatly increased in recent past because of their biocompatible, non-allergic and biodegradable nature. Natural polymers are usually hydrophilic supports, so in order to be a carrier of a hydrophobic drug their nature needs to be changed. Each developed system behaves differently towards different drugs in terms of loading and sustained release of the drug as well. In the present work we report differential binding of piperine & curcumin with cetyltrimethylammonium bromide (CTAB) modified cellulose, alginate and pectin. Difference in interaction between the piperine and curcumin with supports has been visualized using in-vitro as well as in-silico studies. Initial results obtained after in-silico studies have been validated via time dependent anti-trypsin, serum protein binding, anti-cathepsin, anti-oxidant, and anti-α-amylase activities. FT-IR, SEM, fluorescence and Particle size have been used to characterize the piperine loaded on CTAB-modified polymeric supports.

Polymeric Systems for the Controlled Release of Flavonoids.

Flavonoids are natural compounds that are attracting great interest in the biomedical field thanks to the wide spectrum of their biological properties. Their employment as anticancer, anti-inflammatory, and antidiabetic drugs, as well as for many other pharmacological applications, is extensively investigated. One of the most successful ways to increase their therapeutic efficacy is to encapsulate them into a polymeric matrix in order to control their concentration in the physiological fluids for a prolonged time. The aim of this article is to provide an updated overview of scientific literature on the polymeric systems developed so far for the controlled release of flavonoids. The different classes of flavonoids are described together with the polymers most commonly employed for drug delivery applications. Representative drug delivery systems are discussed, highlighting the most common techniques for their preparation. The flavonoids investigated for polymer system encapsulation are then presented with their main source of extraction and biological properties. Relevant literature on their employment in this context is reviewed in relationship to the targeted pharmacological and biomedical applications.

In vitro evaluation of nanocomposites of linseed mucilage and k-carrageenan loaded with Achyrocline satureioides nanoemulsion: a gradual-release candidate of antimicrobials for the treatment of bovine mastitis.

This research paper presents the development and evaluation of pioneering nanocomposites (NCs) based on the combination of k-carrageenan and linseed mucilage. When loaded with macela extract nanoemulsion they present an innovative approach for the sustained release of antimicrobial herbal constituents, specifically tailored for bovine mastitis treatment. The NCs, encompassing various ratios of k-carrageenan and linseed mucilage polymers (8:2, 7:3, and 5:5 w/w) with 1.25 mg of macela extract/g of gel, underwent in vitro assessment, emphasizing viscosity, degradation speed, release of herbal actives from macela nanoemulsion and antimicrobial activity. The NCs exhibited thermoreversible characteristics, transitioning from liquid at 60°C to a gel at 25°C. NCs allowed a gradual release of phenolic compounds, reaching approximately 80% of total phenolics release (w/v) within 72 h. NCs inhibited the growth of MRSA (ATCC 33592) until 8 h of incubation. No toxic effect in vitro of NCs was found on MAC-T cells. Thus, the developed materials are relevant for the treatment of bovine mastitis, especially in the dry period, and the data support future evaluations in vivo.

Antiviral Compounds Based on Natural Astragalus polysaccharides (APS): Research and Foresight in the Strategies for Combating SARS-CoV-2 (COVID-19).

Today, finding natural polymers with desirable properties for use in various industries is one of the critical axes of research in the world. Polysaccharides are a group of natural polymers that have various applications in the pharmaceutical industry. The attachment of monosaccharides forms polysaccharides through glycosidic bonds that are widely found in various sources, including plants. Genus Astragalus belongs to the Fabaceae family. Plants belonging to this genus have different polysaccharides. Astragalus polysaccharides (APS) have attracted a great deal of attention among natural polymers because they are non-toxic, biodegradable, and biocompatible. Currently, APS have great drug potential for curing or treating various diseases. Due to the different biological activities of polysaccharides, including Astragalus, this study has investigated the chemical structure of APS, reporting on the antiviral and anti-inflammatory activities as well as stimulation of cytokine secretion by these polysaccharides. Also, in this study, the pharmaceutical approaches of APS compounds, as a natural, new and inexpensive source, have been discussed as suitable candidates for use in pharmaceutical formulations and preparation of new drugs to control COVID-19 infection.

Spray-drying microencapsulation of tea extracts using green starch, alginate or carrageenan as carrier materials.

Tea industry generates many by-products which could be used to produce and incorporate bioactive tea extracts (TE) into nutraceuticals, cosmetics and/or clinical applications. However, sensibility to external factors is a major disadvantage hindering its utilization. This study deals with the implementation and characterization of suitable biopolymer delivery systems based on starch, carrageenan or alginate, as microencapsulation, to stabilize and protect TE through innovative thin-carbohydrate-coated formulations. TE were spray-dried and microencapsulated in recycled carrier materials (alginate, carrageenan or starch). Product yields varied from 55 to 58%. High microencapsulation and loading efficiencies were achieved (60-93% and 65-84%, respectively). Antioxidant capacity varied from 32 to 46 g Trolox/100 g extract, within different carrier-systems; which also showed promising rheological and UV-protective properties when transformed into gels. Total phenolic content, particle-size distribution, HPSEC-analysis, SEM-analysis and FTIR-analysis were also performed. In sum, this paper characterizes and discusses the high potential of these recycled carbohydrate-coated microparticles for future applications.

Preparation of Hydrogels Based on Modified Pectins by Tuning Their Properties for Anti-Glioma Therapy.

The extracellular matrix (ECM) of the central nervous system (CNS), characterized by low stiffness and predominance of carbohydrates on protein components, mediates limited cell proliferation and migration. Pectins are polysaccharides derived from plants and could be very promising for a tunable hydrogel design that mimics the neural ECM. Aiming to regulate gel structure and viscoelastic properties, we elaborated 10 variants of pectin-based hydrogels via tuning the concentration of the polymer and the number of free carboxyl groups expressed in the degree of esterification (DE). Viscoelastic properties of hydrogels varied in the range of 3 to 900 Pa for G' and were chosen as the first criteria for the selection of variants suitable for CNS remodeling. For extended reciprocal characterization, two pairs of hydrogels were taken to test pectins with opposite DEs close to 0% and 50%, respectively, but with a similar rheology exceeding 100 Pa (G'), which was achieved by adjusting the concentration of pectin. Hydrogel swelling properties and in vitro stability, together with structure characterization using SEM and FTIR spectroscopy, displayed some differences that may sense for biomedical application. Bioassays on C6 and U87MG glioblastoma cultures testified the potential prospects of the anti-glioma activity of hydrogels developed by decreasing cell proliferation and modulating migration but supporting the high viability of neural cells.

Malva parviflora Leaves Mucilage: An Eco-Friendly and Sustainable Biopolymer with Antioxidant Properties.

Malva parviflora L. is an edible and medicinal herb containing mucilaginous cells in its leaves. Mucilage obtained from M. parviflora leaves (MLM) was extracted in distilled water (1:10 w/v) at 70 °C followed by precipitation with alcohol. Preliminary phytochemical tests were performed to assess the purity of the extracted mucilage. Results showed that the yield of mucilage was 7.50%, and it was free from starch, alkaloids, glycosides, saponins, steroids, lipids and heavy metals. MLM had 16.19% carbohydrates, 13.55% proteins and 4.76% amino acids, which indicate its high nutritional value. Physicochemical investigations showed that MLM is neutral and water-soluble, having 5.84% moisture content, 15.60% ash content, 12.33 swelling index, 2.57 g/g water-holding capacity and 2.03 g/g oil-binding capacity. The functional properties, including emulsion capacity, emulsion stability, foaming capacity and stability increased with increased concentrations. Micromeritic properties, such as bulk density, tapped density, Carr's index, Hausner ratio, and angle of repose, were found to be 0.69 g/cm3, 0.84 g/cm3, 17.86%, 1.22 and 28.5, respectively. Scanning electron microscopy (SEM) showed that MLM is an amorphous powder possessing particles of varying size and shape; meanwhile, rheological studies revealed the pseudoplastic behavior of MLM. The thermal transition process of MLM revealed by a differential scanning calorimetry (DSC) thermogram, occurring at a reasonable enthalpy change (∆H), reflects its good thermal stability. The presence of functional groups characteristic of polysaccharides was ascertained by the infrared (IR) and gas chromatography/mass spectrometry (GC/MS) analyses. GC revealed the presence of five neutral monosaccharides; namely, galactose, rhamnose, arabinose, glucose and mannose, showing 51.09, 10.24, 8.90, 1.80 and 0.90 mg/g of MLM, respectively. Meanwhile, galacturonic acid is the only detected acidic monosaccharide, forming 15.06 mg/g of MLM. It showed noticeable antioxidant activity against the DPPH (1,1-diphenyl-2-picrylhydrazyl) radical with an IC50 value of 154.27 µg/mL. It also prevented oxidative damage to DNA caused by the Fenton reagent, as visualized in gel documentation system. The sun protection factor was found to be 10.93 ± 0.15 at 400 µg/mL. Thus, MLM can be used in food, cosmetic and pharmaceutical industry and as a therapeutic agent due to its unique properties.

A thermo-sensitive chitosan/pectin hydrogel for long-term tumor spheroid culture.

Hydrogels represent a key element in the development of in vitro tumor models, by mimicking the typical 3D tumor architecture in a physicochemical manner and allowing the study of tumor mechanisms. Here we developed a thermo-sensitive, natural polymer-based hydrogel, where chitosan and pectin were mixed and, after a weak base-induced chitosan gelation, a stable semi-Interpenetrating Polymer Network formed. This resulted thermo-responsive at 37 °C, injectable at room temperature, stable up to 6 weeks in vitro, permeable to small/medium-sized molecules (3 to 70 kDa) and suitable for cell-encapsulation. Tunable mechanical and permeability properties were obtained by varying the polymer content. Optimized formulations successfully supported the formation and growth of human colorectal cancer spheroids up to 44 days of culture. The spheroid dimension and density were influenced by the semi-IPN stiffness and permeability. These encouraging results would allow the implementation of faithful tumor models for the study and development of personalized oncological treatments.

Bupivacaine-eluting soy protein structures for controlled release and localized pain relief: An in vitro and in vivo study.

Burn pain is known to be excruciating, and while burn care has greatly advanced, treatment for burn-related pain is lacking. Current pain relief methods include systemic administration of analgesics, which does not provide high drug concentration at the wound site. In the present study, soy protein was used as the base material for bupivacaine-loaded hybrid wound dressings. The effect of the formulation on the drug release profile was studied using high performance liquid chromatography, and the cytotoxicity was tested on human fibroblasts. A second-degree burn model in rats was used to quantify the efficacy of the wound dressings in vivo, using the Rat Grimace Scale. All tested films exhibited high biocompatibility, and the drug release profiles showed rapid release during the initial 5 hr and a continuous slower release for another 24 hr. Significant pain relief was achieved in the animal trials, proving a decrease of 51-68% in pain levels during days 1-3 post-burn. Hence, the results indicate a safe and controlled bupivacaine release for a period of more than 24 hr, effectively treating pain caused by second-degree burns. The understanding of the formulation-properties effects, together with our in vivo study, enables to advance this field toward tailorable systems with high therapeutic potential.

Rheological and thermo-mechanical evaluation of bio-based chitosan/pectin blends with tunable ionic cross-linking.

Bio-based chitosan/pectin blend films were prepared by solution casting and fully characterized in terms of their viscoelastic, thermo-mechanical and water affinity properties. Dynamic light scattering and rheological analyses served as a probe that polyelectrolyte complexes were formed through COO-/NH3+ ionic cross-linking, changing the chitosan/pectin solutions from Newtonian to pseudoplastic gel-like systems. The highest degree of ionic cross-linking has been found at a specific mass ratio (chitosan/pectin 25/75) and solid-state data were obtained in detail using dynamic mechanical thermal analysis. Ionic cross-linking was determining on the physical properties of chitosan/pectin blends, which was demonstrated by the thermo-mechanical spectra, high water contact angle and tensile strength of films. The specific thermo-mechanical properties of the chitosan/pectin films can be specifically modulated according to the chitosan/pectin mass ratio to ensure successfully applications in medicine, drug delivery, agricultural and food coatings.

Lecithin, gelatin and hydrolyzed collagen orally disintegrating films: functional properties.

Orally disintegrating films (ODFs) can transport natural active compounds such as ethanol extract of propolis (EEP). This paper aimed to investigate the effect of lecithin on different gelatin and hydrolyzed collagen (HC) polymeric matrices with addition of EEP. ODFs were prepared by casting technique and were characterized (color parameters, water content, mechanical properties, microstructure, disintegration time (DT), infrared spectroscopy (FTIR), contact angle (CA), swelling degree and total phenolic content). The mechanical properties were influenced by HC. The microstructure demonstrated increased porosity and roughness in films with EEP, and the addition of lecithin resulted in an increase in the number of pores. Lecithin-gelatin and lecithin-EEP-gelatin interactions were observed by FTIR. The addition of HC and EEP reduced the DT and CA, and HC and lecithin reduced the swelling capacity. However, the swelling capacity was not affected by presence of EEP. The addition of lecithin to gelatin and HC ODFs may improve the incorporation and the oral transport of active compounds such as EEP.

Novel porous soy protein-based blend structures for biomedical applications: Microstructure, mechanical, and physical properties.

Use of naturally derived materials for biomedical applications is steadily increasing. Soy protein has advantages over various types of natural proteins employed for biomedical applications due to its low price, nonanimal origin, and relatively long storage time and stability. In the current study, blends of soy protein with other polymers (gelatin, alginate, pectin, polyvinyl alcohol, and polyethylene glycol) were developed and studied. The mechanical tensile properties of dense films were studied in order to select the best secondary polymer for porous three-dimensional structures. The porous soy-gelatin and soy-alginate structures were then studied for physical properties, degradation behavior, and microstructure. The results show that these blends can be assembled into porous three-dimensional structures by combining chemical crosslinking with freeze-drying. The soy-alginate blends are advantageous over soy-gelatin blends, demonstrated better stability, and degradation time along with controlled swelling behavior due to more effective crosslinking and higher water uptake than soy-gelatin blends. Water vapor transmission rate experiments showed that all porous blend structures were in the desired range for burn treatment [2000-2500 g/(m(2) d)] and can be controlled by the crosslinking process. We conclude that these novel porous three-dimensional structures have a high potential for use as scaffolds for tissue engineering, especially for skin regeneration applications. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1109-1120, 2016.

Injectable pectin hydrogels produced by internal gelation: pH dependence of gelling and rheological properties.

The production of injectable pectin hydrogels by internal gelation with calcium carbonate is proposed. The pH of pectin was increased with NaOH or NaHCO3 to reach physiological values. The determination of the equivalence point provided evidence that the pH can be more precisely modulated with NaHCO3 than with NaOH. Degradation and inability to gel was observed for pectin solutions with pH 5.35 or higher. Therefore, pectin solutions with pH values varying from 3.2 (native pH) to 3.8 were chosen to produce the gels. The increase of the pH for the crosslinked hydrogels, as well as the reduction of the gelling time and their thickening, was dependent upon the amount of calcium carbonate, as confirmed by rheology. Hydrogel extracts were not cytotoxic for L-929 fibroblasts. On the overall, the investigated formulations represent interesting injectable systems providing an adequate microenvironment for cell, drug or bioactive molecules delivery.

Preparation and characterization of microcapsules of Pterodon pubescens Benth. by using natural polymers

An oleaginous fraction obtained from an alcohol extract of the fruit of Pterodon pubescens Benth. (FHPp) was microencapsulated in polymeric systems. These systems were developed using a complex coacervation method and consisted of alginate/medium-molecular-weight chitosan (F1-MC), alginate/chitosan with greater than 75% deacetylation (F2-MC), and alginate/low-molecular-weight chitosan (F3-MC). These developed systems have the potential to both mask the taste of the extract, and to protect its constituents against possible chemical degradation. The influence of the formulation parameters and process were determined by chemical profiling and measurement of the microencapsulation efficiency of the oleaginous fraction, and by assessment of microcapsule morphology. The obtained formulations were slightly yellow, odorless, and had a pleasant taste. The average diameters of the microcapsules were 0.4679 µm (F2-MC), 0.5885 µm (F3-MC), and 0.9033 µm (F1-MC). The best formulation was F3-MC, with FHPp microencapsulation efficiency of 61.01 ± 2.00% and an in vitro release profile of 75.88 ± 0.45%; the content of vouacapans 3-4 was 99.49 ± 2.80%. The best model to describe the release kinetics for F1-MC and F3-MC was that proposed by Higuchi; however, F2-MC release displayed first-order kinetics; the release mechanism was of the supercase II type for all formulations.

Uma fração oleaginosa obtida do extrato etanólico de frutos de Pterodon pubescens Benth (FHPp) foi microencapsulada em um sistema polimérico. Estes sistemas foram desenvolvidos utilizando o método de coacervação complexa, constituído de alginato/quitosana massa molecular média (F1-MC), alginato/quitosana com desacetilação superior a 75% (F2-MC) e alginato/quitosana de massa molecular baixa (F3-MC). Estes sistemas desenvolvidos têm o potencial tanto de mascarar o sabor do extrato, quanto de protegê-lo de possível degradação química. A influência dos parâmetros de formulação e processo foram determinadas por caracterização química, determinação da eficiência de microencapsulação da fração oleaginosa e por avaliação morfológica da microcápsula. As formulações mostraram-se ligeiramente amareladas, inodoras e com sabor agradável. Os diâmetros médios das microcápsulas foram de 0,4679 µm (F2-MC), 0,5885 µm (F3-MC) e 0,9033 µm (F1-MC). A melhor formulação foi F3-MC, considerando-se que apresentou eficiência de encapsulação de 61,01 ± 2,00%, e perfil de liberação in vitro de 75,88 ± 0,45%; o conteúdo dos vouacapanos 3-4 foi 99,49 ± 2,80%. O melhor modelo para descrever a cinética de liberação foi o modelo proposto por Higuchi para F1-MC e F3-MC, entretanto, para F2-MC foi o modelo de primeira ordem, e o mecanismo de liberação foi do tipo super caso II para todas as formulações.