Mucoadhesive improvement of alginate microspheres as potential gastroretentive delivery carrier by blending with Bletilla striata polysaccharide

Gastroprotective effects of polysaccharides from purple sweet potato (Ipomoea batatas (L.) Lam) on an ethanol-induced gastric ulcer via regulating immunity and activating the PI3K/Akt/Rheb/mTOR pathway

The study aimed to investigate the alleviation of an ethanol-induced gastric ulcer in mice by apolysaccharide (PSP) from purple sweet potato (Ipomoea batatas (L.) Lam) and explore the mechanism. The anti-ulcer activity was determined by histopathological evaluation, total gastric acidity, pepsin activity, gastric ulcer index and gastric ulcer inhibition rate. The expression levels of inflammatory factors were detected using ELISA. A special protein meter was used to detect the content of immunoglobulin lgM, immunoglobulin lgG, and complements C3 and C4 in the serum of mice. The expression of CD4+/CD8+ lymphocyte subsets of mice was detected using flow cytometry. Western blot analysis was used to examine the effect of PSP on the PI3K/Akt/Rheb/mTOR pathway. The results showed that PSP could effectively reduce the total gastric acidity, pepsin activity, and the index and inhibition rate of gastric ulcers. At the same time, PSP could significantly increase the levels of immunoglobulins (lgG and lgM) and complements (C3 and C4). It could also increase the activity of peritoneal macrophages in mice and the expression of CD4+/CD8+ in the spleen. ELISA analysis showed that the contents of TNF-α, IL-1β and IL-6 were significantly decreased and the content of IL-10 was significantly increased in the PSP group. The western blot analysis showed that PSP could upregulate the relative protein expressions of MUC5AC, PI3K, p-Akt, Rheb and mTOR. These results indicate that PSP can activate the PI3K/Akt/Rheb/mTOR signaling pathway to improve the immunity of mice and maintain the balance of the immune system, thereby protecting the gastric mucosa and improving stress gastric ulcers.

Gastric acid-responsive deformable sodium alginate/Bletilla striata polysaccharide in situ gel for the protection and treatment of alcohol-induced peptic ulcers

First-line drugs for peptic ulcer (PU) treatment are typically limited by poor targeting and adverse effects associated with long-term use. Despite recent advancements in novel therapeutic approaches for PU, the development of sustained-release delivery systems tailored to specific pathological characteristics remains challenging. Persistent inflammation, particularly gastric inflammatory microenvironment imbalance, characterizes the PU. In this study, we prepared an in situ gel composed of sodium alginate, deacetylated gellan gum, calcium citrate, and Bletilla striata polysaccharide (BSP) to achieve sustained release of BSP. The BSP in situ gel demonstrated favorable fluidity in vitro and completed self-assembly in vivo in response to the acidic milieu at a pH of 1.5. Furthermore, the shear, extrusion, and deformation properties increased by 26.4 %, 103.7 %, and 46.3 %, respectively, with long-term gastric retention (4 h) and mucosal adaptation. Animal experiments confirmed that the BSP in situ gel could attenuate necrotic injury and inflammatory cell infiltration, maintain mucosal barrier integrity, regulate cytokine imbalance and inflammation-associated hyperapoptosis, thus effectively alleviate the inflammatory microenvironmental imbalance in PU without significant side effects. Overall, our findings demonstrated that the BSP in situ gel is a promising therapeutic strategy for PU and opens avenues for developing self-assembled formulations targeting the pathological features of PUs.

Dual properties of pharmacological activities and preparation excipient: Bletilla striata polysaccharides

Bletilla striata has been used for thousands of years and shows the functions of stopping bleeding, reducing swelling, and promoting healing in traditional applications. For Bletilla striata, Bletilla striata polysaccharides (BSP) is the main active ingredient, exhibiting biological functions of anti-inflammatory, anti-oxidant, anti-fibrotic, immune modulation, anti-glycation, and so on. In addition, BSP has exhibited the characteristics of excipient such as bio-adhesion, bio-degradability, and bio-safety and has been prepared into a series of preparations such as nanoparticles, microspheres, microneedles, hydrogels, etc. BSP, as both a drug and an excipient, has already aroused more and more attention. In this review, publications in recent years related to the extraction and identification, biological activities, and excipient application of BSP are reviewed. Specifically, we focused on the advances in the application of BSP as a formulation excipient. We hold opinion that BSP not only needed more researches in the mechanisms, but also the development into hydrogels, nano-formulations, tissue engineering, and so on. And we believe that this paper provides a beneficial reference for further BSP innovation and in-depth research and promotes the use of these natural products in pharmaceutical applications.

A Gellan Gum/Sodium Alginate-based gastric-protective hydrogel loaded with a combined herbal extract consisting of Panax notoginseng, Bletilla striata and Dendrobium officinale

One Chinese herbal combination consisting of Panax notoginseng, Bletilla striata and Dendrobium officinale (PBD) is an effective Traditional Chinese Medicine (TCM) prescription and is widely used in clinics to treat gastric ulcers due to their safety and effectiveness compared with chemical agents, such as aspirin and omeprazole. Herein, an in situ forming gel (ISFG) based on Gellan Gum (GG) and Sodium Alginate (SA) was designed to deliver extracts of PBD prescription (EPBDP). The central composite design optimized prescription dosage was 0.1 % w/v of GG and 0.5 % w/v of SA. Gels prepared with this formulation demonstrated outstanding fluidity and instantaneous gel formation. In vitro release data showed that sustained drug release occurred in the gel, and the gel was pH-sensitive. The rheological tests confirmed the formation of stable gel, which exhibited strong viscosity and elasticity. In vitro adhesion assays revealed that the gel had strong gastric mucosal adhesion, while in vivo residual rate experiments of active ingredients revealed that the gel might greatly improve the gastric retention of active ingredients. Animal studies demonstrated that the gel was effective in treating gastric ulcers. Hence, the results of the study show that EPBDP-ISFG, a highly pH-sensitive sustained-release system, is effective.

Alginate-based drug carrier systems to target inflammatory bowel disease: A review

Inflammatory bowel disease (IBD) is an inflammatory disorder that affects the gastrointestinal tract. IBD has become an increasingly common condition in both developed and developing nations over the last few decades, owing to a variety of factors like a rising population and diets packed with processed and junk foods. While the root pathophysiology of IBD is unknown, treatments are focused on medications aimed to mitigate symptoms. Alginate (AG), a marine-derived polysaccharide, is extensively studied for its biocompatibility, pH sensitivity, and crosslinking nature. This polymer is thoroughly researched in drug delivery systems for IBD treatment, as it is naturally available, non-toxic, cost effective, and can be easily and safely cross-linked with other polymers to form an interconnected network, which helps in controlling the release of drugs over an extended period. There are various types of drug delivery systems developed from AG to deliver therapeutic agents; among them, nanotechnology-based systems and hydrogels are popular due to their ability to facilitate targeted drug delivery, reduce dosage, and increase the therapeutic efficiency. AG-based carrier systems are not only used for the sustained release of drug, but also used in the delivery of siRNA, interleukins, and stem cells for site directed drug delivery and tissue regenerating ability respectively. This review is focussed on pathogenesis and currently studied medications for IBD, AG-based drug delivery systems and their properties for the alleviation of IBD. Moreover, future challenges are also be discoursed to improve the research of AG in the field of biopharmaceuticals and drug delivery.

Extraction, structural-activity relationships, bioactivities, and application prospects of Bletilla striata polysaccharides as ingredients for functional products: A review

Bletilla striata is a well-known medicinal plant with high pharmaceutical and ornamental values. Polysaccharide is the most important bioactive ingredient in B. striata and has various health benefits. Recently, B. striata polysaccharides (BSPs) have attracted much attention from industries and researchers due to their remarkable immunomodulatory, antioxidant, anti-cancer, hemostatic, anti-inflammatory, anti-microbial, gastroprotective, and liver protective effects. Despite the successful isolation and characterization of B. striata polysaccharides (BSPs), there is still limited knowledge regarding their structure-activity relationships (SARs), safety concerns, and applications, which hinders their full utilization and development. Herein, we provided an overview of the extraction, purification, and structural features, as well as the effects of different influencing factors on the components and structures of BSPs. We also highlighted and summarized the diversity of chemistry and structure, specificity of biological activity, and SARs of BSP. The challenges and opportunities of BSPs in the food, pharmaceutical, and cosmeceutical fields are discussed, and the potential development and future study direction are scrutinized. This article provides comprehensive knowledge and underpinnings for further research and application of BSPs as therapeutic agents and multifunctional biomaterials.

Unification of medicines and excipients: The roles of natural excipients for promoting drug delivery

INTRODUCTION

Drug delivery systems (DDSs) formed by natural active compounds be instrumental in developing new green excipients and novel DDS from natural active compounds (NACs). 'Unification of medicines and excipients'(UME), the special inherent nature of the natural active compounds, provides the inspiration and conduction to achieve this goal.

AREAS COVERED

This review summarizes the typical types of NACs from herbal medicine, such as saponins, flavonoids, polysaccharides, etc. that act as excipients and their main application in DDS. The comparison of the drug delivery systems formed by NACs and common materials and the primary formation mechanisms of these NACs are also introduced to provide a deepened understanding of their performance in DDS.

EXPERT OPINION

Many natural bioactive compounds, such as saponins, polysaccharides, etc. have been used in DDS. Diversity of structure and pharmacological effects of NACs turn out the unique advantages in improving the performance of DDSs like targeting ability, adhesion, encapsulation efficiency(EE), etc. and enhancing the bioavailability of loaded drugs.

Formulation and Evaluation of Xanthan Gum Microspheres for the Sustained Release of Metformin Hydrochloride

This work aimed to formulate xanthan gum microspheres for the encapsulation of metformin hydrochloride, according to the process of ionotropic gelation. The obtained microparticles, based on various fractions of xanthan gum (0.5-1.25), were subjected to different physico-chemical tests and a drug release study. Microspheres with an average size varying between 110.96 μm and 208.27 μm were obtained. Encapsulation efficiency reached 93.11% at a 1.25% biopolymer concentration. The swelling study showed a swelling rate reaching 29.8% in the gastric medium (pH 1.2) and 360% in the intestinal medium (pH 6.8). The drug release studies showed complete metformin hydrochloride release from the beads, especially those prepared from xanthan gum at the concentration of 1.25%, in intestinal medium at 90.00% after 6 h. However, limited and insignificant drug release was observed within the gastric medium (32.50%). The dissolution profiles showed sustained release kinetics.

Bletilla striata Polysaccharide Nanoparticles Improved the Therapeutic Efficacy of Omeprazole on the Rat Gastric Ulcer Induced by Ethanol

Gastric ulcers are a common clinical presentation affecting anyone, regardless of their age or gender. Nanoparticles (NPs) containing Bletilla striata polysaccharide (BSP) and omeprazole (OME) were investigated in the study for their therapeutic effect on gastric ulcers. Ethanol-induced gastric ulcers in rats (240 ± 30 g) were established. Our OME-BSP NPs were more stable than free OME in the acidic environment and can increase the absorption of OME in rat stomach, which was confirmed by in situ gastric absorption and distribution experiments. The extended blood circulation of OME-BSP NPs was also observed in rats with gastric ulcer. More importantly, OME-BSP NPs not only decreased the area of gastric ulcer and inhibited gastric acid secretion but also reversed gastric tissue damage and cell apoptosis, as revealed by HE and TUNEL staining. Subsequent SOD, MDA, PGE₂, IL-6, and TNF-α tests further verified the superiority of OME-BSP NPs against rat gastric ulcer, which properly originated from superior antioxidant and anti-inflammatory effects. As a result, our OME-BSP NPs' drug delivery system improved the stability and absorption of OME in the rat stomach and achieved targeted treatment of gastric ulcers.

Formulation, Statistical Optimization, and In Vivo Pharmacodynamics of Cydonia oblonga Mucilage/Alginate Mucoadhesive Microspheres for the Delivery of Metformin HCl

In recent years, attention has shifted toward the utilization of natural polymers for encapsulation and sustained release of health-hazardous drugs. The purpose of this work is to define and assess the sustained delivery potential and mucoadhesive potential of a Cydonia oblonga mucilage (COM) and sodium alginate (Na-Alg)-constituting polymeric delivery carrier of antidiabetic drugs with a specific end goal to retain metformin HCl in the stomach while expanding the drug's bioavailability. Metformin HCl was encapsulated in mucoadhesive microspheres by an ionic gelation method. Polymers with different combinations were tried, and the resulting mucoadhesive COM/Na-Alg microspheres were assessed for particle size (mm) PS/Y₁, drug encapsulation efficiency DEE (%)/Y₂, and in vitro percentage cumulative drug release R_12h/Y₃ using Drug Design Expert software version 10. The response surface methodology by a 3²-central composite design predicted optimal synthesis parameters for the microspheres to be 295 mg for COM and 219 mg for Na-Alg. An optimized formulation was prepared under these conditions and used to evaluate the micrometric properties, morphology and structural characteristics, swelling behavior, in vitro drug release, and kinetics. Acute toxicity studies were carried out on blank COM/Na-Alg microspheres to deem them safe for in vivo studies. The DEE (%) was calculated to be 85.8 ± 1.67, whereas scanning electron microscopy (SEM) showed a coarse surface with characteristic wrinkles and cracks with an optical microscopic particle size of 0.96 ± 2.45. The ex vivo tests showed great mucoadhesive properties and good swelling behavior with pH-responsive drug release and a significant reduction in in vivo blood glucose levels. The results advocated the use of optimized microspheres to enhance the bioactivity with a possible dose reduction, making it less symptomatic, reducing the expense of the treatment, and subsequently facilitating better patient compliance.

Tailoring functional spray-dried powder platform for efficient donepezil nose-to-brain delivery

Shortcomings of oral donepezil administration in the treatment of Alzheimer's disease have paved the way for ongoing investigations towards more efficient and safe donepezil nose-to-brain delivery. Herein we present the development of advantageous powder platform for donepezil nose-to-brain delivery, coupling careful design of chitosan and mannitol-based carrier matrix with spray-drying technology advantages and early consideration of adequate nasal administration mode, employing QbD approach. Unprecedentedly, ultrasonic nozzle was used to atomise the drying feed in response to size-related requirements for nasal aerosol particles. The optimised spray-drying process resulted in free-flowable dry powder with a great majority of particles larger than 10 µm, ensuring localised nasal deposition upon aerosolization, as evidenced by using 3D-printed nasal cavity model. QbD approach coupling formulation, process and administration parameters enabled optimisation of drug deposition profile reaching tremendously high 65.5 % of the applied dose deposited in the olfactory region. The leading formulation exhibited favourable swelling, mucoadhesion, drug release and permeation-enhancing properties, suiting the needs for efficient brain-targeted delivery. Results of in vitro biocompatibility and physico-chemical stability studies confirmed the leading formulation potential for safe and efficient donepezil nose-to-brain delivery. The obtained results encourage extending the study to an appropriate in vivo model needed for the final proof-of-concept.

Current Advances in Multifunctional Nanocarriers Based on Marine Polysaccharides for Colon Delivery of Food Polyphenols

Inflammatory bowel disease (IBD) has been considered as a chronic disease that is difficult to cure and needs lifelong treatment. Marine polysaccharides with good biocompatibility and biodegradability, mucoadhesion, sensitivity to external stimuli, and targeting ability can be used as wall materials for oral colon-targeted delivery of polyphenols in nutrition intervention of IBD. This manuscript reviewed the latest progress in the design, preparation, and characterization of marine polysaccharides-derived multifunctional nanocarriers for polyphenol colon delivery. Chitosan, sodium alginate, chondroitin sulfate, and hyaluronic acid were discussed in the preparation of polyphenol delivery systems. The design strategy, synthesis methods, and structure characterization of multifunctional polyphenol carriers including stimuli-responsive nanocarriers, mucoadhesive and mucus-penetrating nanocarriers, colon targeted nanocarriers, and bioactive compounds codelivery nanocarriers were reviewed in the alleviation of IBD. The research perspectives in the preparation and characterization of delivery carriers using marine polysaccharide as materials were proposed for their potential application in food bioactive components.

A review on the applications of Traditional Chinese medicine polysaccharides in drug delivery systems

Traditional Chinese medicine polysaccharides (TCMPs) are plentiful and renewable resources with properties such as biocompatibility, hydrophilicity, biodegradability, and low cytotoxicity. Because the polysaccharide molecular chain contains a variety of active groups, different polysaccharide derivatives can be easily produced through chemical modification. They have been increasingly used in drug delivery systems (DDS). However, the potential of polysaccharides is usually ignored due to their structural complexity, poor stability or ambiguity of mechanisms of actions. This review summarized the applications of TCMPs in DDS around four main aspects. The general characteristics of TCMPs as drug delivery carriers, as well as the relationships between structure and function of them were summarized. Meanwhile, the direction of preparing multifunctional drug delivery materials with synergistic effect by using TCMPs was discussed. This review aims to become a reference for further research of TCMPs and their derivatives, especially applications of them as carriers in pharmaceutical preparation industry.

Preparation of Acyclovir-Containing Solid Foam by Ultrasonic Batch Technology

In recent years, the application of solid foams has become widespread. Solid foams are not only used in the aerospace field but also in everyday life. Although foams are promising dosage forms in the pharmaceutical industry, their usage is not prevalent due to decreased stability of the solid foam structure. These special dosage forms can result in increased bioavailability of drugs. Low-density floating formulations can also increase the gastric residence time of drugs; therefore, drug release will be sustained. Our aim was to produce a stable floating formula by foaming. Matrix components, PEG 4000 and stearic acid type 50, were selected with the criteria of low gastric irritation, a melting range below 70 °C, and well-known use in oral drug formulations. This matrix was melted at 54 °C in order to produce a dispersion of active substance and was foamed by different gases at atmospheric pressure using an ultrasonic homogenizer. The density of the molded solid foam was studied by the pycnometer method, and its structure was investigated by SEM and micro-CT. The prolonged drug release and mucoadhesive properties were proved in a pH 1.2 buffer. According to our experiments, a stable foam could be produced by rapid homogenization (less than 1 min) without any surfactant material.

Development of the mussel-inspired pH-responsive hydrogel based on Bletilla striata polysaccharide with enhanced adhesiveness and antioxidant properties

Recently, smart hydrogels have attracted much attention for their abilities to respond to subtle changes in external and internal stimuli. Also, natural polysaccharide-based biomaterials are more appealing for their biocompatibility and biodegradability. However, limitations owing to their complex compositions and mechanisms, cumbersome synthetic routes, and single function call for a simple and effective strategy to develop novel multifunctional smart hydrogels. Herein, this developed work was achieved based on Bletilla striata polysaccharide (BSP), a kind of natural glucomannan with diverse bioactivities and biocompatibility, we fabricated a low-cost multifunctional hydrogel by oxidizing the catechol groups of carboxymethylated BSP(CBSP)-dopamine(DA) conjugate with adhesion, antioxidant, and pH-responsive properties. In this hydrogel system, CBSP as the backbone material, was negatively charged and conferred the hydrogel with pH sensitivity. The presence of catechol groups greatly enhanced the tissue adhesion and antioxidant capacities of the hydrogel. Meanwhile, the highly porous structure of hydrogel allowed berberine to be encapsulated and released to exhibit excellent and long-lasting antibacterial activity. In summary, the adhesion, antioxidant, pH-sensitive, and antibacterial multifunctional hydrogel showed massive potential in the biomedical field.

Mucoadhesive properties of nanogels based on stimuli-sensitive glycosaminoglycan-graft-pNIPAAm copolymers

Mucoadhesive formulations capable of situ gelation are promising for improving ocular drug delivery. Here we investigated two types of nanogels based on anionic glycosaminoglycans with grafted thermo-responsive poly(N-isopropylacrylamide) chains. One type of nanogels were formed by thermo-induced gelling of heparin-graft-poly(N-isopropylacrylamide) and chondroitin sulfate-graft-poly(N-isopropylacrylamide) copolymers. Another type of nanogels was based on the same copolymers, but terminal groups of thermosensitive macromolecular chains were modified to form covalent disulfide cross-links. All types of nanogels were studied towards their ability to encapsulate and release model drug - dexamethasone. Mucoadhesivity of both thermo-gelled and covalently cross-linked polymeric systems, as well as their ability to interact with dexamethasone, was assessed by microscale thermophoresis (MST). Mucoadhesion properties were also evaluated by isothermal titration calorimetry (ITC), which were in good correlation with MST data. The presence of disulfide linkages and thiol groups were shown to favor improved binding of cross-linked nanogels to mucin. Moreover, in vivo intraocular pressure studies showed that presence of polymers in solution can alter the ocular absorption of carbonic anhydrase inhibitor from eyedrops. The pharmacological effect was in line with mucoadhesive properties of these copolymers.

Process Optimization for the Continuous Production of a Gastroretentive Dosage Form Based on Melt Foaming

Several drugs have poor oral bioavailability due to low or incomplete absorption which is affected by various effects as pH, motility of GI, and enzyme activity. The gastroretentive drug delivery systems are able to deal with these problems by prolonging the gastric residence time, while increasing the therapeutic efficacy of drugs. Previously, we developed a novel technology to foam hot and molten dispersions on atmospheric pressure by a batch-type in-house apparatus. Our aim was to upgrade this technology by a new continuous lab-scale apparatus and confirm that our formulations are gastroretentive. At first, we designed and built the apparatus and continuous production was optimized using a Box-Behnken experimental design. Then, we formulated barium sulfate-loaded samples with the optimal production parameters, which was suitable for in vivo imaging analysis. In vitro study proved the low density, namely 507 mg/cm3, and the microCT record showed high porosity with 40 μm average size of bubbles in the molten suspension. The BaSO4-loaded samples showed hard structure at room temperature and during the wetting test, the complete wetting was detected after 120 min. During the in vivo study, the X-ray taken showed the retention of the formulation in the rat stomach after 2 h. We can conclude that with our device low-density floating formulations were prepared with prolonged gastric residence time. This study provides a promising platform for marketed active ingredients with low bioavailability.

Improved efficacy of Panax notoginseng saponin loaded into BSP/alginate microspheres for the treatment of alcoholic gastric ulcers

Previously, we have reported the evaluations of alginate and Bletilla striata polysaccharide (BSP) in formulation of microsphere, which is a muco-adhesive carrier and can achieve a long duration of gastric retention. The combination of Panax notoginseng (Burk.) and B. striata is a traditional Chinese herbal formula that is used to treat gastric ulcers. BSP, an effective ingredient of B. striata, possesses both medicinal and excipient functions. Panax notoginseng saponin (PNS), which can easily dissolve in water, is the main effective ingredient in P. notoginseng (Burk.) for the treatment of gastric ulcers. However, microspheres containing PNS could directly cause drug leakage, ultimately reducing the encapsulation rate. In this study, PNS was fabricated into a hydrophobic dispersion with slow-release characteristics. Subsequently, PNS was packaged into BSP/alginate microspheres to improve the encapsulation rate. The prepared PNS-loaded microspheres were round, the release characteristics aligned with the Weibull equation, and the active ingredients were released by diffusion and erosion. The developed microspheres improved the effects of PNS and synergistically exerted the pharmaceutical effects of BSP on acute gastric ulcers.

Models to evaluate the barrier properties of mucus during drug diffusion

Mucus is widely disseminated in the nasal cavity, oral cavity, respiratory tract, eyes, gastrointestinal tract, and reproductive tract to prevent the invasion of pathogenic bacteria and toxins. The mucus layer through its continuous secretion can prevent the passage of macromolecular substances such as pathogenic bacteria and toxins, thereby reducing the occurrence of inflammation. Without a doubt, mucus also hinders oral absorption. The physiological and biochemical properties of intestinal mucus and the different types of mucus barrier models need to be predominated. To find ways to increase the bioavailability of drugs in the future, this article summarizes mucus composition, barrier properties, mucus models, and mucoadhesive/mucopenetrating particles to highlight the information they can afford. Collectively, the review seeks to provide a state-of-the-art roadmap for researchers who must contend with this critical barrier to drug delivery.

Gastro-retentive drug delivery systems: a recent update on clinical pertinence and drug delivery

Gastro-retentive drug delivery systems are some of the best technologies delivered through oral route. These mainly came into picture for their effective local action in the GI region, specifically for the drugs with narrow absorption window. In the recent decades, several technologies have evolved showing different mechanisms for retaining the drug in GI region for longer duration with increased bioavailability. Floatable, mucoadhesive, swelable, magnetic, nanofibrous, high-density, and expandable systems have been investigated extensively as the potential gastro-retentive strategies. The advances in the technologies studied, their clinical pertinence, and methods of drug delivery are described in this review with their immense future utilities. Their entry into the pharmaceutical market is a huge matter to look into as most of the studied strategies are facing problems and hence are underrated to overcome the clinical trials. Their success in the clinical trials are enormously required for gaining their access into the pharmaceutical market. Selection of the right technology for the right purpose through the right mechanism of action is to be done for obtaining the system with desired activity.

Alginate: From Food Industry to Biomedical Applications and Management of Metabolic Disorders

Initially used extensively as an additive and ingredient in the food industry, alginate has become an important compound for a wide range of industries and applications, such as the medical, pharmaceutical and cosmetics sectors. In the food industry, alginate has been used to coat fruits and vegetables, as a microbial and viral protection product, and as a gelling, thickening, stabilizing or emulsifying agent. Its biocompatibility, biodegradability, nontoxicity and the possibility of it being used in quantum satis doses prompted scientists to explore new properties for alginate usage. Thus, the use of alginate has been expanded so as to be directed towards the pharmaceutical and biomedical industries, where studies have shown that it can be used successfully as biomaterial for wound, hydrogel, and aerogel dressings, among others. Furthermore, the ability to encapsulate natural substances has led to the possibility of using alginate as a drug coating and drug delivery agent, including the encapsulation of probiotics. This is important considering the fact that, until recently, encapsulation and coating agents used in the pharmaceutical industry were limited to the use of lactose, a potentially allergenic agent or gelatin. Obtained at a relatively low cost from marine brown algae, this hydrocolloid can also be used as a potential tool in the management of diabetes, not only as an insulin delivery agent but also due to its ability to improve insulin resistance, attenuate chronic inflammation and decrease oxidative stress. In addition, alginate has been recognized as a potential weight loss treatment, as alginate supplementation has been used as an adjunct treatment to energy restriction, to enhance satiety and improve weight loss in obese individuals. Thus, alginate holds the promise of an effective product used in the food industry as well as in the management of metabolic disorders such as diabetes and obesity. This review highlights recent research advances on the characteristics of alginate and brings to the forefront the beneficial aspects of using alginate, from the food industry to the biomedical field.

Encapsulation of Black Seed Oil in Alginate Beads as a pH-Sensitive Carrier for Intestine-Targeted Drug Delivery: In Vitro, In Vivo and Ex Vivo Study

Black seed oil (BSO) has been used for various therapeutic purposes around the world since ancient eras. It is one of the most prominent oils used in nutraceutical formulations and daily consumption for its significant therapeutic value is common phenomena. The main aim of this study was to develop alginate-BSO beads as a controlled release system designed to control drug release in the gastrointestinal tract (GIT). Electrospray technology facilitates formulation of small and uniform beads with higher diffusion and swelling rates resulting in process performance improvement. The effect of different formulation and process variables was evaluated on the internal and external bead morphology, size, shape, encapsulation efficiency, swelling rate, in vitro drug release, release mechanism, ex vivo mucoadhesive strength and gastrointestinal tract qualitative and quantitative distribution. All the formulated beads showed small sizes of 0.58 ± 0.01 mm (F8) and spherical shape of 0.03 ± 0.00 mm. The coefficient of weight variation (%) ranged from 1.37 (F8) to 3.93 (F5) ng. All formulations (F1–F9) were studied in vitro for release characteristics and swelling behaviour, then the release data were fitted to various equations to determine the exponent (ns), swelling kinetic constant (ks), swelling rate (%/h), correlation coefficient (r²) and release kinetic mechanism. The oil encapsulation efficiency was almost complete at 90.13% ± 0.93% in dried beads. The maximum bead swelling rate showed 982.23 (F8, r² = 0.996) in pH 6.8 and the drug release exceeded 90% in simulated gastrointestinal fluid (pH 6.8). Moreover, the beads were well distributed throughout various parts of the intestine. This designed formulation could possibly be advantageous in terms of increased bioavailability and targeted drug delivery to the intestine region and thus may find applications in some diseases like irritable bowel syndrome.