Search Results (48)

Background/Objectives: This study aimed to develop an advanced oral delivery platform for Salvia officinalis (S. officinalis) extract by co-encapsulating it with inulin and pectin in alginate-based microbeads, formulated via ionic gelation. Methods: The microbeads were comprehensively characterized, including the assessment of morphology, particle size, encapsulation efficiency, swelling behavior, in vitro dissolution, and enzymatic stability, and Caco-2 cell-based assays for cytocompatibility, permeability, and transepithelial electrical resistance. Antioxidant capacity and anti-inflammatory effects were also evaluated. Results: The resulting microbeads (~275 µm) achieved > 90% encapsulation efficiency and exhibited pronounced swelling (~90%). The release of S. officinalis constituents displayed pH sensitivity, with sustained release in simulated intestinal fluid, alongside significant enhancement of enzymatic stability. Encapsulation led to markedly improved permeability of bioactive compounds across Caco-2 monolayers, attributable to reversible modulation of tight junctions. Encapsulated extract retained potent antioxidant activity and significantly reduced pro-inflammatory cytokines. The formulation, across various concentrations, further promoted the growth and viability of Lactobacillus strains. Conclusions: Collectively, these findings demonstrate that alginate–inulin–pectin microbeads provide a multifunctional system for stabilizing S. officinalis extract, enabling controlled release, enhanced intestinal absorption, and maintained bioefficacy. Importantly, the formulation also promoted Lactobacillus viability, indicating a prebiotic effect and offering considerable potential for improved oral therapeutic applications. Full article

Citrus by-products are increasingly recognized as a valuable source of bioactive compounds (BCs), particularly flavonoids. Their incorporation into food matrices as functional ingredients aligns with sustainability goals and consumer demand for health-promoting products. However, challenges such as poor stability and undesirable sensory properties limit their direct use in food systems. This study aimed to develop and evaluate functional cookies enriched with microencapsulated flavonoid-rich extracts derived from lemon and orange peels. Flavonoids were extracted with hydroethanolic solvent and characterized by HPLC-DAD. The extracts exhibited high total flavonoid contents: 1960.1 mg/L for orange and 845.7 mg/L for lemon. The extracts were encapsulated using a 1% sodium alginate and 1.36% corn starch blend, producing thermally stable microbeads with flavonoid retention higher than 85% after heating at 230 °C for 30 min. These microbeads were incorporated into gluten-free oat and buckwheat cookies, delivering 166.11 mg/100 g (orange) and 177.13 mg/100 g (lemon) of flavonoids in the product, which covers approximately one-third of the recommended daily intake. Sensory analysis using triangle tests (ISO 4120) (n = 23) showed no significant difference (p > 0.05) between control and enriched cookies, indicating successful masking of potential bitterness or astringency associated with flavonoids. These results demonstrate the effectiveness of microencapsulation in protecting citrus flavonoid-rich extracts and support the development of sustainable, health-oriented bakery products. Moreover, this approach promotes the valorization of agro-industrial by-products, contributing to a more circular food supply chain. Full article

Enzyme entrapment in alginate hydrogel microbeads is an effective method of immobilization for industrial applications, but many fabrication methods for alginate microbeads involve oil, organic solvents, or high temperatures that reduce enzymatic activity. In this study, we employed an oil- and solvent-free gas-shearing technique to prepare alginate microbeads for the entrapment of Candida rugosa lipase (CRL), thereby minimizing thermal- and solvent-induced inactivation. To enhance immobilization efficiency and reusability, the effects of gas flow rate, alginate concentration, and cross-linking metal ions were systematically investigated. CRL entrapped in Ba- and Fe-alginate microbeads showed superior immobilization yield, activity retention, and activity recovery compared with CRL entrapped in conventional Ca-alginate microbeads. Notably, both Ba- and Fe-alginate microbeads exhibited significantly enhanced stability, with half-lives up to 127-fold greater than that of free CRL at 60 °C, and maintained substantially higher pH stability across the tested range. Ba-alginate microbeads provided greater pH stability and substrate affinity, whereas Fe-alginate microbeads demonstrated enhanced thermal stability and catalytic turnover. These findings highlight gas-shearing as a scalable and gentle fabrication method for producing high-performance alginate microbeads with tunable properties, making them suitable for enzyme entrapment in diverse biocatalytic applications. Full article

This study presents an innovative iontophoretic delivery system for glycolic acid (GA) based on polysaccharide microbeads embedded within an electrolyte hydrogel. The mi-crobeads, fabricated using a peristaltic pump, exhibited a uniform morphology with an average diameter of 1078 ± 140.38 μm and were successfully integrated into a hydrogel matrix (thickness: 4542.55 ± 337.24 μm). Comprehensive physicochemical characterization (FT-IR, XRD, SEM) confirmed effective component integration. The hydrogel demonstrated optimal mechanical properties with a tensile strength of 0.02 ± 0.003 MPa and reliable adhesion to various substrates, while maintaining excellent self-healing capabili-ties—post-repair conductivity remained sufficient to power an LED indicator. The material demonstrated favorable conductivity under various storage conditions while maintaining non-cytotoxic properties. Notably, microbead incorporation preserved electrochemical performance, as demonstrated by stable behavior in cyclic voltammetry using an Ag/AgCl reference system. Iontophoretic testing revealed significantly enhanced glycolic acid delivery at −1.0 V com-pared to passive diffusion. The system, combining PVA, PAA, alginate, [Bmim]BF₄, and E. prolifera polysaccharides with gellan gum, shows strong potential for advanced cosmetic dermatology applications requiring precise active ingredient delivery. Full article

The use of pharmaceuticals to treat human and animal diseases has resulted in the increase of antibiotic traces in the water system and soil, thus raising concerns about the environmental aspect. In this study, sodium alginate (SA) and carboxymethyl chitosan (CMCS) hydrogel microbeads were developed to enhance the adsorption of antibiotics by applying electrostatic spray in the fabrication of microbeads. Two hydrogel microbead sizes, SC-400 (~400 µm) and SC-2000 (~2000 µm), were used for the adsorption of tetracycline (TC) and ciprofloxacin (CIP) antibiotics in single and binary systems. The microbeads exhibited a good adsorption capacity and were able to achieve a maximum adsorption at pH 7 and 25 °C. Adsorption kinetics expressed suitability in the pseudo-second-order kinetic model for TC and CIP antibiotics. These results demonstrate that both single and binary systems align well with the Freundlich and Temkin isotherm models, indicating their suitability in explaining the adsorption mechanisms. These mechanisms predominantly involve electrostatic interactions between the SA/CMCS hydrogel microbeads and the antibiotics TC and CIP. This study highlights the capability of using SA/CMCS hydrogel microbeads for antibiotic removal and other environmental applications. Full article

Microbeads of raspberry extract were produced using encapsulation matrices alginate + pea protein isolate + psyllium mucilage, alginate + pea protein isolate + psyllium mucilage + okra, and alginate + pea protein isolate + psyllium mucilage + Aloe ferox gel + gallic acid using freeze-drying method. The microbeads were characterised and assessed for their effectiveness on the release, bioaccessibility, of anthocyanin components and antioxidant activities during in vitro digestion. Alginate + pea protein isolate + psyllium mucilage + Aloe ferox gel + gallic acid matrix showed the highest encapsulation efficiency of 91.60% while the lowest encapsulation efficiency was observed in alginate + pea protein isolate + psyllium mucilage + okra (69.94%). Scanning electron microscope images revealed spherical shapes and varying surface morphologies for different encapsulation matrices. Despite the differences observed in Fourier transform infrared spectra, microbeads showed similar thermal degradation patterns. X-ray diffractograms showed amorphous structures for different encapsulation matrices. Comparatively, alginate+ pea protein isolate + psyllium mucilage + Aloe ferox gel + gallic acid microbeads exhibited the highest bioaccessibility for total phenols (93.14%), cyanidin-3-O-sophoroside (54.61%), and cyanidin-3-O-glucoside (55.30%). The encapsulation matrices of different biopolymer combinations (alginate+ pea protein isolate+ psyllium mucilage, alginate + pea protein isolate + psyllium mucilage + okra, and alginate + pea protein isolate + psyllium mucilage + Aloe ferox gel + gallic acid) enhanced anthocyanin stability and protected it against in vitro degradation of bioactive compounds. Full article

This study explores the potential of Vigna mungo gum as a sustainable and innovative natural polymer for developing microbeads for the controlled delivery of vildagliptin, a widely used antidiabetic agent. Unlike conventional natural polymers, Vigna mungo gum offers unique biocompatibility, biodegradability, and an eco-friendly production process, distinguishing it as a superior candidate for drug delivery systems. Microbeads were prepared by combining Vigna mungo gum with sodium alginate and inducing gelation using calcium carbonate. Scanning electron microscopy (SEM) revealed a rough, porous microbead surface, advantageous for drug encapsulation and controlled release. Drug release studies demonstrated sustained release kinetics, highlighting the effectiveness of this formulation. These findings underscore the novelty of Vigna mungo gum as a promising platform for antidiabetic drug delivery, providing a sustainable alternative to existing polymer systems. Full article

Medical and aromatic plant extracts are often very sensitive to environmental, gastrointestinal, and processing conditions despite their health benefits. Therefore, they can be rapidly inactivated. Microencapsulation is used to overcome such challenges. In this study, phenolic antioxidants from rosemary (Rosmarinus officinalis L.) were encapsulated in alginate beads by means of ionic gelation. A Box–Behnken design with response surface methodology (BBD–RSM) was used with three numeric factors (calcium chloride concentration, alginate concentration, and hardening time) to achieve the best formulation in terms of encapsulation efficiency, antioxidant activity, and morphological characteristics. Generally, the sodium alginate concentration of the microbeads was the most critical factor (p < 0.0001) for the quality of the products. The optimal encapsulation conditions were accessed using concentrations with almost 6% calcium chloride and 2% alginate, and a time of 10 min for bead hardening in order to obtain the highest responses (30.01% encapsulation efficiency, 7.55 mg-TEAC/g-DM of antioxidant activity value as measured by the DPPH method, a sphericity factor of 0.05, and a roundness of 0.78). At the optimum point, the microbeads were determined to be spherical in shape, and the bulk density value was measured as 0.34 ± 0.01 g/mL. Full article

This study investigated the effects of combining sodium alginate (ALG) with various natural hydrocolloids on the microstructure and release behaviors of microbeads. The encapsulation solutions were prepared at a 1:1 (w/w) ratio with ALG as the control and carrageenan (CAR), locust bean gum (LBG), acacia gum (ACA), pectin (PEC), and carboxymethyl cellulose (CMC) as experimental groups. Each formulation contained 0.2% (w/v) tartrazine and was extruded into a CaCl₂ solution for bead production. Encapsulation efficiency varied across formulations, with the lowest in the control (ALG-ALG) and highest in ALG-CAR and ALG-CMC, reaching 74% and 78%, respectively. The microbead sizes ranged from 2.07 to 3.48 mm, with the lowest particle diameter observed in ALG-ACA composites. Surface analysis showed smooth and uniform microbeads in the control (ALG-ALG), while ALG-LBG microbeads were rougher. Release kinetics were assessed using various models, with the Higuchi model best describing the release for most formulations (highest R² values). Tartrazine release followed pseudo-Fickian behavior in all formulations, with slower release in ALG-ACA and faster release in ALG-LBG microbeads. This study fills a gap in understanding how the incorporation of different natural hydrocolloids influences both the encapsulation efficiency and release dynamics of alginate-based microbeads, providing valuable insights for applications in food and pharmaceutical industries. Full article

This study focuses on evaluating the efficiency of acid-tolerant Lacticaseibacillus paracasei bacteria encapsulated in an alginate-based gel matrix during repeated sourdough fermentation cycles, as well as their preservation during storage and throughout baking at high temperature. A double-coating procedure was applied, involving the encapsulation of bacterial cells in calcium alginate, which was further coated with chitosan. The encapsulation efficiency (EE) did not show significant difference between alginate and alginate–chitosan (97.97 and 96.71%, respectively). The higher number of L. paracasei bacteria was preserved in double-coated microbeads, with survivability rates of 89.51% and 96.90% in wet and dried microbeads, respectively. Encapsulated bacteria demonstrated effective fermentation ability, while double gel-coated cells exhibited slower acidification during sourdough fermentation, maintaining higher efficiency in the second fermentation cycle. The addition of freeze-dried, alginate-based gel-encapsulated bacteria (2–4%, w/w flour) significantly (p < 0.05) improved bread quality and extended its shelf life. A double-layer coating (alginate–chitosan) can be introduced as an innovative strategy for regulating the release of lactic acid bacteria and optimizing fermentation processes. Powdered alginate or alginate–chitosan gel-based L. paracasei microcapsules, at appropriate concentrations, can be used in the production of baked goods with acceptable quality and sensory properties, achieving a lactic acid bacteria count of approximately 10⁶ CFU/g in the crumb, thereby meeting the standard criteria for probiotic bakery products. Full article

Pseudomonas aeruginosa is an opportunistic Gram-negative bacterium that remains a prevalent clinical and environmental challenge. Quorum-sensing (QS) molecules are effective biomarkers in pinpointing the presence of P. aeruginosa. This study aimed to develop a convenient-to-use, whole-cell biosensor using P. aeruginosa reporters individually encapsulated within alginate-poly-L-lysine (alginate-PLL) microbeads to specifically detect the presence of bacterial autoinducers. The PLL-reinforced microbeads were prepared using a two-step method involving ionic cross-linking and subsequent coating with thin layers of PLL. The alginate-PLL beads showed good stability in the presence of a known cation scavenger (sodium citrate), which typically limits the widespread applications of calcium alginate. In media containing synthetic autoinducers—such as N-(3-oxo dodecanoyl) homoserine lactone (3-oxo-C₁₂-HSL) and N-butanoyl-L-homoserine lactone (C₄-HSL), or the cell-free supernatants of planktonic or the flow-cell biofilm effluent of wild P. aeruginosa (PAO1)—the encapsulated bacteria enabled a dose-dependent detection of the presence of these QS molecules. The prepared bioreporter beads remained stable during prolonged storage at 4 and −80 °C and were ready for on-the-spot sensing without the need for recovery. The proof-of-concept, optical fiber-based, and whole-cell biosensor developed here demonstrates the practicality of the encapsulated bioreporter for bacterial detection based on specific QS molecules. Full article

Osteoporosis, a terminal illness, has emerged as a global public health problem in recent years. The long-term use of bone anabolic drugs to treat osteoporosis causes multi-morbidity in elderly patients. Alternative therapies, such as allogenic and autogenic tissue grafts, face important issues, such as a limited source of allogenic grafts and tissue rejection in autogenic grafts. However, stem cell therapy has been shown to increase bone regeneration and decrease osteoporotic bone formation. Stem cell therapy combined with betulin (BET) supplementation might be adequate for bone remodeling and new bone tissue generation. In this study, the effect of BET on the viability and osteogenic differentiation of hFOB 1.19 cells was investigated. The cells were encapsulated in alginate–gelatin (AlGel) microbeads. In vitro tests were conducted during the 12 d of incubation. While BET showed cytotoxic activity (>1 µM) toward non-encapsulated hFOB 1.19 cells, encapsulated cells retained their functionality for up to 12 days, even at 5 µM BET. Moreover, the expression of osteogenic markers indicates an enhanced osteo-inductive effect of betulin on encapsulated hFOB 1.19, compared to the non-encapsulated cell culture. The 3D micro-environment of the AlGel microcapsules successfully protects the hFOB 1.19 cells against BET cytotoxicity, allowing BET to improve the mineralization and differentiation of osteoblast cells. Full article

Fennel essential oil (EO) is well known for its biological activities and wide potential for use in the food, cosmetic, and pharmaceutical industries, where the main challenge is to achieve higher stability of EO. This study aimed to evaluate the potential of electrostatic extrusion for encapsulation of fennel EO by examining the effects of alginate (1%, 1.5%, and 2%) and whey protein (0%, 0.75%, and 1.5%) concentrations and drying methods on the encapsulation efficiency, loading capacity, bead characteristics, and swelling behavior of the produced fennel EO microbeads. Results revealed that electrostatic extrusion proved to be effective for encapsulating fennel EO, with whey protein addition enhancing the examined characteristics of the obtained microbeads. Freeze-drying exhibited superior performance compared to air-drying. Optimal encapsulation efficiency (51.95%) and loading capacity (78.28%) were achieved by using 1.5% alginate and 0.75% whey protein, followed by freeze-drying. GC-MS analysis revealed no differences in the qualitative aspect of the encapsulated and initial EO, with the encapsulated EO retaining 58.95% of volatile compounds. This study highlighted the potential of electrostatic extrusion using alginate and whey protein as a promising technique for fennel EO encapsulation while also emphasizing the need for further exploration into varied carrier materials and process parameters to optimize the encapsulation process and enhance product quality. Full article

Bacterial infections are among the most significant health problems/concerns worldwide. A very critical concern is the rapidly increasing number of antibiotic-resistant bacteria, which requires much more effective countermeasures. As nature’s antibacterial entities, bacteriophages shortly (“phages”) are very important alternatives to antibiotics, having many superior features compared with antibiotics. The development of phage-carrying controlled-release formulations is still challenging due to the need to protect their activities in preparation, storage, and use, as well as the need to create more user-friendly forms by considering their application area/site/conditions. Here, we prepared gelatin hydrogel microbeads by a two-step process. Sodium alginate was included for modification within the initial recipes, and these composite microbeads were further coated with chitosan. Their swelling ratio, average diameters, and Zeta potentials were determined, and degradations in HCl were demonstrated. The target bacteria Escherichia coli (E.coli) and its specific phage (T4) were obtained from bacterial culture collections and propagated. Phages were loaded within the microbeads with a simple method. The phage release characteristics were investigated comparatively and were demonstrated here. High release rates were observed from the gelatin microbeads. It was possible to reduce the phage release rate using sodium alginate in the recipe and chitosan coating. Using these gelatin-based microbeads as phage carrier matrices—especially in lyophilized forms—significantly improved the phage stability even at room temperature. It was concluded that phage release from gelatin hydrogel microbeads could be further controlled by alginate and chitosan modifications and that user-friendly lyophilized phage formulations with a much longer shelf life could be produced. Full article

The present paper describes the preparation and characterization of novel microbeads from alginate filled with nanoclay such as halloysite nanotubes (HNTs). HNTs were used as support for the growth of layered double hydroxide (LDH) crystals producing a flower-like structure (HNT@LDH). Such nanofiller was loaded with grapefruit seed oil (GO), an active compound with antimicrobial activity, up to 50% wt. For comparison, the beads were also loaded with HNT and LDH separately, and filled with the same amount of GO. The characterization of the filler was performed using XRD and ATR spectroscopy. The beads were analyzed through XRD, TGA, ATR and SEM. The functional properties of the beads, as nanocarriers of the active compound, were investigated using UV-vis spectroscopy. The release kinetics were recorded and modelled as a function of the structural characteristics of the nanofiller. Full article