Preparation and characterization of Ganoderma lucidum spores-loaded alginate microspheres by electrospraying

Modification of Ganoderma lucidum spore shells into probiotic carriers: selective loading and colonic delivery of Lacticaseibacillus rhamnosus and effective therapy of inflammatory bowel disease

Inflammatory bowel disease (IBD) is a chronic inflammation with a high incidence rate. Many probiotics, including Lacticaseibacillus rhamnosus (L. rhamnosus), have shown promise in IBD treatment. The therapeutic effects of most probiotics are greatly decided by the available live cells in the disease lesion, which is compromised as they pass through the gastric juice and intestinal tract, resulting in a loss of activity. To improve probiotic delivery efficiency in the intestinal tract, broken Ganoderma lucidum spore shells (bGLS) were explored as a carrier to enhance the intestinal tract delivery of L. rhamnosus SHA113, a probiotic that has been verified to have capability to treat IBD. It was found the bGLS treated with iturin A and hydrochloric acid (IH-bGLS) had much higher affinity to probiotic cells than the untreated ones. This is possibly due to the enhancement of hydrophobic and positive charge of bGLS. Furthermore, IH-bGLS demonstrated an 81% loading efficiency for L. rhamnosus SHA113 and 2.2% for Escherichia coli. More importantly, loading in IH-bGLS greatly enhanced the delivery of L. rhamnosus SHA113 cells to the colon and prolonged their retention time from 48 to over 120 h (P < 0.01). The mechanisms might be related to the enhancement of probiotic cell adhesion to the gastrointestinal mucosa, increase of mucus secretion and the upregulated expression of tight junction proteins, occludin and ZO-1, in the colon. The results of the animal experiment showed that the therapeutic effects of L. rhamnosus SHA113 on IBD were greatly enhanced when they were loaded with IH-bGLS. The novelty of this research is in the development of probiotic carriers from bGLS, which has significance in the improvement of intestinal delivery efficiency and the therapeutic effects of probiotics on IBD. This system may have attractive application in the enhancement of probiotic delivery efficiency in the intestinal tract, which is important to ensure and enhance the beneficial effects of probiotics.

Metal nanoparticles and carbohydrate polymers team up to improve biomedical outcomes

The convergence of carbohydrate polymers and metal nanoparticles (MNPs) holds great promise for biomedical applications. Researchers aim to exploit the capability of carbohydrate matrices to modulate the physicochemical properties of MNPs, promote their therapeutic efficiency, improve targeted drug delivery, and enhance their biocompatibility. Therefore, understanding various attributes of both carbohydrates and MNPs is the key to harnessing them for biomedical applications. The many distinct types of carbohydrate-MNP systems confer unique capabilities for drug delivery, wound healing, tissue engineering, cancer treatment, and even food packaging. Here, we introduce distinct physicochemical/biological properties of carbohydrates and MNPs, and discuss their potentials and shortcomings (alone and in combination) for biomedical applications. We then offer an overview on carbohydrate-MNP systems and how they can be utilized to improve biomedical outcomes. Last but not least, future perspectives toward the application of such systems are highlighted.

Potentialities of Ganoderma lucidum extracts as functional ingredients in food formulation

Owing to the recognized therapeutic characteristics of G. lucidum, it is one of the most extensively researched mushrooms as a chemopreventive agent and as a functional food. It is a known wood-degrading basidiomycete possessing numerous pharmacological functions and is termed a natural pharmacy store due to its rich number of active compounds which have proved to portray numerous therapeutic properties. This current review highlights studies on the potentialities of G. lucidum extracts as functional ingredients on organoleptic and nutritional properties of food products (e.g., dairy, wine, beverage, bakery, meat, and other products). In addition, the study delved into various aspects of encapsulated G. lucidum extracts, their morphological and rheological characteristics, prebiotic and immunomodulatory importance, the effects on apoptosis, autophagy, cancer therapy, inflammatory responses, oxidative stress, antioxidant activities, and safety concerns. These findings have significant implications for the development of new products in the food and pharmaceutical industries. On the other hand, the various active compounds extracted from G. lucidum exhibited no toxic or adverse effects, and the appeal for it as a dietary food, natural remedy, and health-fortifying food is drastically increasing as well as attracting the interest of both the industrial and scientific communities. Furthermore, the formation of functional foods based on G. lucidum appears to have actual promise and exciting prospects in nutrition, food, and pharmaceutical sciences.

Modifications of Ganoderma lucidum spores into digestive-tissue highly adherent porous carriers with selective affinity to hydrophilic or hydrophobic drugs

Ganoderma lucidum spores (GLSs) have been suggested to provide optimal structures for transporting orally bioavailable drugs. However, the double-layer wall and cavities of GLSs are naturally closed. This study aimed to modify GLSs into porous carriers by opening the layers and internal cavity with iturin A (IA) followed by potassium hydroxide (KOH) or hydrochloric acid (HCl). The (IA + KOH)- and (IA + HCl)-treated GLS carriers exhibited a high loading rate of 301.50 ± 2.33 and 268.18 ± 7.72 mg/g for the hydrophilic methylene blue (MB) and hydrophobic rifampicin (RF), respectively. The mechanisms underlying the modification involved the enhancement of the specific surface area with IA and the exposure of hydrophilic groups or hydrophobic groups of the GLSs with KOH or HCl. The sustained 48-h molecule-release profiles of the MB- and RF-loaded GLS carriers were best fitted using a first-order kinetics model in simulated gastric (or intestinal) fluid compared with other models. In mice, the designed GLS carriers had high adhesion capacities onto the mucosa of the digestive tract and long retention times (120 h), and even promoted the secretion of mucus and expression of several key intestinal barrier proteins. This study provided a new method to modify GLSs into oral carriers with selective drug affinity, high loading capacity, sustained drug release, and high adhesion to the digestive tract.

Electrospinning and Electrospraying: Emerging Techniques for Probiotic Stabilization and Application

Probiotics are beneficial for human health. However, they are vulnerable to adverse effects during processing, storage, and passage through the gastrointestinal tract, thus reducing their viability. The exploration of strategies for probiotic stabilization is essential for application and function. Electrospinning and electrospraying, two electrohydrodynamic techniques with simple, mild, and versatile characteristics, have recently attracted increased interest for encapsulating and immobilizing probiotics to improve their survivability under harsh conditions and promoting high-viability delivery in the gastrointestinal tract. This review begins with a more detailed classification of electrospinning and electrospraying, especially dry electrospraying and wet electrospraying. The feasibility of electrospinning and electrospraying in the construction of probiotic carriers, as well as the efficacy of various formulations on the stabilization and colonic delivery of probiotics, are then discussed. Meanwhile, the current application of electrospun and electrosprayed probiotic formulations is introduced. Finally, the existing limitations and future opportunities for electrohydrodynamic techniques in probiotic stabilization are proposed and analyzed. This work comprehensively explains how electrospinning and electrospraying are used to stabilize probiotics, which may aid in their development in probiotic therapy and nutrition.

Encapsulation of Human-Bone-Marrow-Derived Mesenchymal Stem Cells in Small Alginate Beads Using One-Step Emulsification by Internal Gelation: In Vitro, and In Vivo Evaluation in Degenerate Intervertebral Disc Model

Cell microencapsulation in gel beads contributes to many biomedical processes and pharmaceutical applications. Small beads (<300 µm) offer distinct advantages, mainly due to improved mass transfer and mechanical strength. Here, we describe, for the first time, the encapsulation of human-bone-marrow-derived mesenchymal stem cells (hBM-MSCs) in small-sized microspheres, using one-step emulsification by internal gelation. Small (127−257 µm) high-mannuronic-alginate microspheres were prepared at high agitation rates (800−1000 rpm), enabling control over the bead size and shape. The average viability of encapsulated hBM-MSCs after 2 weeks was 81 ± 4.3% for the higher agitation rates. hBM-MSC-loaded microspheres seeded within a glycosaminoglycan (GAG) analogue, which was previously proposed as a mechanically equivalent implant for degenerate discs, kept their viability, sphericity, and integrity for at least 6 weeks. A preliminary in vivo study of hBM-MSC-loaded microspheres implanted (via a GAG-analogue hydrogel) in a rat injured intervertebral disc model demonstrated long-lasting viability and biocompatibility for at least 8 weeks post-implantation. The proposed method offers an effective and reproducible way to maintain long-lasting viability in vitro and in vivo. This approach not only utilizes the benefits of a simple, mild, and scalable method, but also allows for the easy control of the bead size and shape by the agitation rate, which, overall, makes it a very attractive platform for regenerative-medicine applications.

Electrospraying as a novel process for the synthesis of particles/nanoparticles loaded with poorly water-soluble bioactive molecules

Hydrophobicity and low aqueous-solubility of different drugs/nutraceuticals remain a persistent challenge for their development and clinical/food applications. A range of nanotechnology strategies have been implemented to address this issue, and amongst which a particular emphasis has been made on those that afford an improved biological performance and tunable release kinetic of bioactives through a one-step process. More recently, the technique of electrospraying (or electrohydrodynamic atomization) has attained notable impulse in virtue of its potential to tune attributes of nano/micro-structured particles (e.g., porosity, particle size, etc.), rendering a near zero-order release kinetics, diminished burst release manner, as well as its simplicity, reproducibility, and applicability to a broad spectrum of hydrophobic and poorly water-soluble bioactives. Controlled morphology or monodispersity of designed particles could be properly obtained via electrospraying, with a high encapsulation efficiency and without unfavorable denaturation of thermosensitive bioactives upon encapsulation. This paper overviews the recent technological advances in electrospraying for the encapsulation of low queues-soluble bioactive agents. State-of-the-art, advantages, applications, and challenges for its implementation in pharmaceutical/food researches are also discussed.

DNA-crosslinked alginate and layered microspheres to modulate the release of encapsulated FITC-dextran

Alginate can be gently crosslinked by calcium into hydrogels and microspheres for the encapsulation and release of proteins and drugs. However, the release is often over short periods unless alginate is also covalently modified or crosslinked. This research aims to sustain the release of encapsulated model drug FITC-dextran by covalently crosslinking alginate with short oligomers DNA because evidence suggests that DNA may also interact with alginate to further increase effective crosslinking. Furthermore, modulating the release of drugs from alginate in response to specific proteins could tailor release profiles to improve patient treatment. This research develops a DNA-crosslinked alginate hydrogel and layered alginate microspheres to encapsulate and then sustain the release FITC-dextran (model drug). An aptamer sequence to hen egg-white lysozyme is included in one DNA strand to allow for the disruption of the crosslinks by interactions with human lysozyme. Alginate was covalently modified with complementary strands of DNA to crosslink the alginate into hydrogels, which had increased crosslinking density when re-swollen (in comparison to controls crosslinked with PEG) and could sustained the release of encapsulated FITC-dextran. When an aptamer sequence for hen lysozyme was included in the DNA crosslinks, the hydrogels decrosslinked when incubated in human lysozyme for 60 days. In addition, calcium alginate microspheres were coated with 3 alternating layers of poly-Lysine, DNA-crosslinked alginate, and poly-L-lysine. FITC-dextran loaded into the microspheres released in a sustained manner past 30 days (into PBS at 37 °C) and would likely continue to release for far longer had the studies continued. When incubated with 3 μM of human lysozyme, a burst release of FITC-dextran occurred from both the hydrogels and microspheres, with no changes in the controls. The increased release was in bursts followed by similar sustained release rates suggesting that the human lysozyme temporarily disrupted the DNA crosslinks which were then re-established or were influenced by interactions between DNA and alginate. Importantly, covalently bound complementary strands of DNA could crosslink the alginate and additional interactions appeared to further sustain the release of encapsulated therapeutics.

Applications of alginate microspheres in therapeutics delivery and cell culture: Past, present and future

Polymers are the backbone of pharmaceutical drug delivery. There are several polymers with varying properties available today for use in different pharmaceutical applications. Alginate is widely used in biomedical research due to its attractive features such as biocompatibility, biodegradability, inertness, low cost, and ease of production and formulation. Encapsulation of therapeutic agents in alginate/alginate complex microspheres protects them from environmental stresses, including the acidic environment in the gastro-intestinal tract (GIT) and enzymatic degradation, and allows targeted and sustained delivery of the agents. Microencapsulation is playing an increasingly important role in drug delivery as evidenced by the recent surge in research articles on the use of alginate in the delivery of small molecules, cells, bacteria, proteins, vaccines, and for tissue engineering applications. Formulation of these alginate microspheres (AMS) are commonly achieved by conventional external gelation method using various instrumental manipulation such as vortexing, homogenization, ultrasonication or spray drying, and each method affects the overall particle characteristics. In this review, an inclusive summary of the currently available methods for the formulation of AMS, its recent use in the encapsulation and delivery of therapeutics, and future outlook will be discussed.

Convenient synthesis of uncovered imprinted microspheres by Ganoderma lucidum spore-stabilized pickering emulsion polymerization and their enhanced recognition of spiramycin

In this work, a new and simple method was developed for the synthesis of uncovered and high-selectivity spiramycin-based molecularly imprinted microspheres (SP-MIMs) by Pickering emulsion polymerization using spiramycin as templates. And surprisingly the solid particles were absent on the surface of imprinted microspheres, which can be ascribed to the Ganoderma lucidum spores (GLS): they were firstly selected to be the stabilizers for the Pickering emulsion in this new strategy. Through a series of adsorption experiments, the uncovered SP-MIMs were proven to possess more excellent selective recognition and removal ability for template SP in aqueous solution. And SP-MIMs could be reused for many times without significant loss of adsorption capacity, indicating the satisfactory regeneration performance. Therefore, SP-MIMs can be employed as a promising adsorbent for the selective removal of SP from aqueous media, and this strategy will contribute to overcoming the shortcomings of stabilizer particles on the surface of the as-prepared imprinting microspheres, because these solid particles lack the special selective recognition activity of template molecules, and may disturb the adsorption effect of imprinting microspheres.

In this work, a new and simple method was developed for the synthesis of uncovered and high-selectivity spiramycin-based molecularly imprinted microspheres (SP-MIMs) by Pickering emulsion polymerization using spiramycin as templates.

Breaking the sporoderm of Ganoderma lucidum spores by combining chemical reaction with physical actuation

The hard and indissolvable sporoderm of Ganoderma lucidum spore (GLS) hinders the release of bioactive components that are significant to disease treatment and vitality enhancement. In this paper, a strategy to break sporoderm was proposed, in which the chemical reaction was cooperated with physical actuation (ultrasonication and refrigeration). Dealing with this chemicophysical treatment, the porous sporoderm of GLS was formed, which was confirmed by scanning electron microscope (SEM). The effect factors and mechanism of breaking sporoderm were discussed, and the efficiency of breaking sporoderm was evaluated by detecting the dissolution behaviour of inner triterpenoids in GLS. In addition, aiming to improve the solubility and stability of GLS product, the β-cyclodextrin was used to seal the holes on sporoderm of GLS product. The results show that the developed method is effective and feasible in producing high-bioactive and stable GLS product.

Janus particle synthesis via aligned non-concentric angular nozzles and electrohydrodynamic co-flow for tunable drug release

A novel non-concentric tilted angle nozzle was designed and manufactured to enable the synthesis of tunable Janus particles. The effect of processing parameters and device configurations on particle structure and dual drug release were explored.