Search Results (381)

Synthetic seed technology, an advanced in vitro propagation method, combines the benefits of micropropagation with the practicality of zygotic seeds, offering an efficient solution for the handling, storage, and transportation of plant propagules. This study represents the first investigation of the role of explant type in blueberry encapsulation. In particular, three non-embryogenic propagules (basal node, median node, and shoot tip) were evaluated in the Brigitta and Duke blueberry cultivars. The artificial endosperm consists of Woody Plant Medium (WPM) macro- and micro-nutrients and Murashige and Skoog vitamins at half concentration, inositol (5 g L⁻¹), Indole-3-butyric acid (IBA) (0.005 mg L⁻¹), zeatin (0.25 mg L⁻¹), and sucrose (50 g L⁻¹). Forty-five days after sowing in in vitro conditions, the encapsulated shoot tips showed better results than basal and median nodes in several parameters, including viability, shoot length, and fresh shoot weight, in both cultivars. In both cultivars, none of the encapsulated propagule types developed roots. These results underscore the advantages of using shoot tips in encapsulation technology for blueberries and provide valuable insights for optimizing encapsulation protocols to improve propagation efficiency. Full article

This study addresses environmental concerns by utilizing banana peel waste to develop innovative adsorbent materials for wastewater treatment, aligning with circular economy principles. Spherical beads were synthesized from sodium alginate mixed with various banana peel-based materials, including pure powder (PBP), activated carbon (AC), and magnetic activated carbon (MAC). These beads were evaluated for their efficiency in removing tetracycline (TC) and hexavalent chromium (Cr(VI)) as model pollutants representing antibiotics and heavy metals, respectively. Characterization of the beads revealed functional groups and thermal stability conducive to effective adsorption. Adsorption trials demonstrated that MAC beads achieved the highest removal efficiencies, up to 92% for TC and 79% for Cr(VI). The adsorption process followed pseudo-second-order kinetics and Langmuir isotherms. Remarkably, the beads retained a significant adsorption capacity across reuse cycles, indicating their regenerative potential. Comparisons with other adsorbents highlight the competitive performance of these banana peel-based materials. The results emphasize the potential of banana peel-derived adsorbents as cost-effective, sustainable solutions for mitigating emerging pollutants in water systems, promoting waste valorization and environmental protection. The research demonstrates a novel approach to sequential adsorption without intermediate regeneration, showing that the beads can effectively remove both tetracycline and chromium (VI) in successive cycles. This finding is particularly significant because it reveals that the presence of previously adsorbed chromium actually enhanced the beads’ capacity for tetracycline removal in the second cycle, suggesting a synergistic effect that had not been previously reported in the literature. These innovations contribute meaningfully to both waste valorization and water treatment technologies, offering new insights into the development of multi-functional adsorbents from agricultural waste materials. 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

Iron oxide-based nanoparticles, such as magnetic nanoparticles (MNPs), have gained significant attention in the area of drug delivery due to their unique magnetic properties, allowing for precise targeting and controlled release of therapeutic agents. Several successful research studies were reported with combinations of magnetic nanoparticles and polysaccharides such as sodium alginate, chitosan, cellulose, etc. The presented research work is based on synthesising MNPs via the co-precipitation method and their successful encapsulation within alginate beads, serving as a promising drug delivery system for aceclofenac, a model drug. The physical and chemical characteristics of both the prepared magnetite nanoparticles and the aceclofenac-loaded MNPs alginate beads were thoroughly examined using scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), Fourier-transform infrared spectroscopy (FTIR), powder X-ray diffraction (PXRD), and vibrating sample magnetometry (VSM). Furthermore, a drug release study was conducted to evaluate the release kinetics of aceclofenac from the prepared MNP alginate beads. The magnetic characteristics of magnetite and MNP beads shed light on the potential application of novel drug delivery systems for magnetically targeted therapeutic interventions. The present research offers valuable insights into the development of magnetic nanoparticle-based drug carriers, paving the way for enhanced drug delivery strategies in the field of pharmaceutical sciences. Full article

Encapsulation techniques play a crucial role in enhancing the stability and viability of probiotics in functional foods. This study investigates the efficacy of calcium–alginate encapsulation, combined with hydrocolloids such as carrageenan, agar, and gelatin, in improving the survival of Lactobacillus rhamnosus GG (LGG) and stabilizing the total phenolic content (TPC) in fermented black goji berry beverages. The results revealed that 1.5% alginate encapsulation, combined with 1% carrageenan, agar, or gelatin and 5% calcium, significantly enhanced the LGG viability and increased the TPC content in the fermented black goji berry beads when compared to calcium–alginate encapsulation alone. Fourier Transform Infrared Spectroscopy (FTIR) confirmed the successful incorporation and interaction of hydrocolloids within the encapsulation matrix. Among the formulations, calcium–alginate–gelatin beads exhibited the highest LGG survival rates after simulated gastric and intestinal digestion. Notably, calcium–alginate beads containing carrageenan preserved LGG viability during simulated gastric and intestinal conditions when co-digested with all tested milk types (high carbohydrate, high protein, and high fat). Co-ingestion with these milk types further improved TPC retention in all bead formulations, as the macronutrients in milk provided protective effects, stabilizing the encapsulated polyphenols and minimizing their degradation during simulated gastric and intestinal digestion. This study highlights the potential of calcium–alginate encapsulation, integrated with hydrocolloids such as carrageenan, agar, or gelatin, to improve probiotic viability and polyphenol stability, offering promising applications for enhancing the functional properties of non-dairy fermented beverages. Full article

This work describes the immobilization and the characterization of purified Penicillium crustosum Thom P22 lipase (PCrL) using adsorption, encapsulation, and adsorption–encapsulation approaches. The maximum activity of the immobilized PCrL on CaCO₃ microspheres and sodium alginate beads was shifted from 37 to 45 °C, compared with that of the free enzyme. When sodium alginate was coupled with zeolite or chitosan, the immobilization yield reached 100% and the immobilized PCrL showed improved stability over a wide temperature range, retaining all of its initial activity after a one-hour incubation at 60 °C. The immobilization of PCrL significantly improves its catalytic performance in organic solvents, its pH tolerance value, and its thermal stability. Interestingly, 95% and almost 50% of PCrL’s initial activity was retained after 6 and 12 cycles, respectively. The characteristics of all PCrL forms were analyzed by X-ray diffraction and scanning electron microscopy combined with energy dispersive spectroscopy. The maximum conversion efficiency of oleic acid and methanol to methyl esters (biodiesel), by PCrL immobilized on CaCO₃, was 65% after a 12 h incubation at 40 °C, while free PCrL generated only 30% conversion, under the same conditions. Full article

Background/Objectives: Focused ultrasound has advantages as an external stimulus for drug delivery as it is non-invasive, has high precision and can penetrate deep into tissues. Here, we report a gold-plated alginate (ALG) hydrogel system that retains highly water-soluble small-molecule fluorescein for sharp off/on release after ultrasound exposure. Methods: The ALG is crosslinked into beads with calcium chloride and layered with a polycation to adjust the surface charge for the adsorption of catalytic platinum nanoparticles (Pt NPs). The coated bead is subject to electroless plating, forming a gold shell. Ultrasound is applied to the gold-plated ALG beads and the release of fluorescein with or without ultrasound stimulation is quantified. Results: Polyethylenimine (PEI), not poly-L-lysine (PLL), is able to facilitate Pt NP adsorption. Gold shell thickness is proportional to the duration of electroless plating and can be controlled. Gold-plated ALG beads are impermeable to the fluorescein cargo and have nearly zero leakage. Exposure to focused ultrasound initiated the release of fluorescein with full release achieved after 72 h. Conclusions: The gold-plated ALG hydrogel is a new material platform that can retain highly water-soluble molecules with a sharp off/on release initiated by focused ultrasound. Full article

The formulation of polysaccharide-based beads encapsulating Trichoderma spp. represents an eco-friendly strategy for promoting sustainable and efficient agriculture. Trichoderma, a beneficial fungus, is well known for its ability to enhance plant growth, combat phytopathogens, and improve soil health. Encapsulating Trichoderma spores in a polysaccharide matrix provides a protective environment that ensures their viability and facilitates their controlled release into the soil. Alginate is a natural polymer found in various species of brown algae and certain bacteria. Pectin is a heteropolysaccharide present naturally in the cell walls of all higher plants. Due to their distinctive characteristics, alginate and pectin are regarded as promising carrier materials for the encapsulation of bioactive agents. In this work, alginate (Alg) beads, pectin (Pec) beads extracted from orange peel, and Alg/Pec composite beads in a 50/50 (w/w) ratio encapsulating Trichoderma S1 (1.83 × 10⁴ conidia/mL) and S2 (1.56 × 10⁸ conidia/mL) were prepared using the ionic gelation method. The moisture content of the prepared beads was evaluated. The size and shape of the beads were determined by analyzing images obtained by an XE3910 optical microscope. The average size of the microcapsules (wet)varied from 1886 ± 6.557 μm to 1942 ± 28.688 μm. All samples were characterized by Fourier transform infrared spectroscopy (FTIR). The overall results demonstrated the successful encapsulation of Trichoderma spp. and highlighted the effects of the different formulations on the physicochemical properties of the beads. Full article

Chronic wounds are a major health problem, affecting millions of people worldwide. Resistance to treatment is frequently observed, requiring an extension of the wound healing time, and improper care can lead to more problems in patients. Smart wound dressings that provide a controlled drug release can significantly improve the healing process. In this paper, alginate beads with white lily leaf extract were prepared and tested for chronic wound healing. The obtained beads were characterized by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). Also, the efficiency of extract encapsulation in alginate was determined as being of. The obtained hydrogel was tested on two normal human cell lines, respectively, dermal fibroblasts (BJ-CRL-2522-ATCC) and endothelial cells (human umbilical vein endothelial cells—HUVEC 2). The longer release of bioactive compounds from plant extract loaded in the alginate hydrogel resulted in more effective wound closure, compared to the extract alone, and scar formation, compared to the alginate hydrogel. Therefore, the effect of the white lily extract in combination with that of sodium alginate hydrogel improves the biological activity of the alginate hydrogel and increases the wound healing properties of the alginate. Full article

In this study, alginate-based composite beads were developed for the delivery of resveratrol, a compound with therapeutic potential. Two formulations were prepared: one with sodium alginate and resveratrol (AR) and another incorporating graphene nanoplatelets (AGR) to improve drug release control. The beads were formed by exploiting alginate’s ability to gel via ionic cross-linking. For the AGR formulation, sodium alginate was dissolved in water, and graphene was dispersed in isopropyl alcohol to achieve smaller flakes. Resveratrol was dissolved in an ethanol/water mixture and added to the graphene dispersion; the resulting solution was mixed with the alginate one. For the AR formulation, the resveratrol solution was mixed directly with the alginate solution. Both formulations were introduced into a calcium chloride solution to form the beads. The release of resveratrol was studied in phosphate-buffered saline at different pH values. Results showed that the presence of graphene in the AGR sample increased drug release, particularly at pH 6.8, indicating a pH-driven release mechanism. Kinetic analysis revealed that the Higuchi model best describes the release mechanism. Finally, cytotoxicity tests showed the biocompatibility of the system in normal human cells. These findings suggest that graphene-enhanced alginate matrices have significant potential for controlled drug delivery applications. Full article

Goldenberry and purple passion fruit contain bioactive compounds (BCs) that can prevent gastrointestinal cancers; hydrogel beads can protect and control their release in the gastrointestinal tract. This study aimed to develop an encapsulating material for fruit hydrogel beads (FHBs) to increase their bioaccessibility and to assess antiproliferative effects. A blend of goldenberry–purple passion fruit was encapsulated using ionic gelation and electrospraying. Through a mixture experimental design with sodium alginate (SA), hydroxypropylmethylcellulose (HPMC) and arabic gum (AG) as components, the following response variables were optimized: polyphenol bioaccessibility and encapsulation efficiency. Polyphenols and antioxidant activity were quantified before and after digestion. Antiproliferative effect was evaluated on Caco-2 colon cancer cells. Variations in formulation proportions had a significant effect (p < 0.05) on most responses. An SA-AG mixture in a 0.75:0.25 ratio maximized polyphenol bioaccessibility to 213.17 ± 19.57% and encapsulation efficiency to 89.46 ± 6.64%. Polyphenols and antioxidant activity were lower in FHBs than in the fruit blend (F). Both F and FHBs inhibited tumor cell proliferation by 17% and 25%, respectively. In conclusion, encapsulating BCs in hydrogel beads with SA-AG can enhance the effectiveness of polyphenols in food applications by improving their bioaccessibility and showing a more pronounced effect in inhibiting tumor cell proliferation. Full article

Enzymatic reactions play an important role in numerous industrial processes, e.g., in food production, pharmaceuticals and the production of biofuels. However, a major challenge when using enzymes in industrial applications is maintaining their stability and activity, especially under harsh operating conditions. To solve this problem, enzyme immobilization techniques have been developed. Immobilization involves fixing the enzymes on solid supports, which increases their stability, enables their reusability and facilitates the easy separation of reaction mixtures. In addition, immobilized enzymes are ideal for continuous flow systems such as millireactors, where they allow better control of reaction conditions, improving efficiency and product consistency. Glucose dehydrogenase is an important enzyme in biotechnology, particularly in biosensors and the production of biofuels, as it catalyzes the oxidation of glucose to gluconolactone, reducing NAD⁺ to NADH. However, like many other enzymes, it tends to lose activity over time. The immobilization of glucose dehydrogenase in a millireactor provides a controlled environment that increases the stability and activity of the enzyme. The aim of this study was to investigate the effects of different immobilization strategies on the performance of glucose dehydrogenase in a 3D printed millireactor. The enzyme was immobilized in alginate gel in three immobilization strategies: as beads, on the bottom surface, and on both the top and bottom surfaces of the millireactor. The results showed that the application of the enzyme on both surfaces improved the glucose conversion two-fold compared to immobilization in beads and four-fold compared to immobilization only on the bottom surface. The dual-surface enzyme immobilization strategy showed the highest efficiency, achieving the highest conversion of 95.76 ± 1.01% (τ = 131 min) and NADH productivity of 0.166 ± 0.01 mmol/(L·min) (τ = 7.11 min) combined with operational stability over five days. Effective diffusion rates comparable to those of aqueous solutions confirmed the suitability of alginate gels for biocatalysis. These advancements highlight the potential of this modular and scalable platform for various biotechnological applications. Full article

Oleogels (organogels) are systems resembling a solid substance based on the gelation of organic solvents (oil or non-polar liquid) through components of low molecular weight or oil-soluble polymers. Such compounds are organogelators that produce a thermoreversible three-dimensional gel network that captures liquid organic solvents. Oleogels based on natural oils are attracting more attention due to their numerous advantages, such as their unsaturated fatty acid contents, ease of preparation, and safety of use. As a result of the research, two oleogels were developed, into which freeze-dried alginate carriers with a probiotic, L. casei, were incorporated. Two techniques were used to produce probiotic-loaded capsules—extrusion and emulsification. Alginate beads obtained by the extrusion process have a size of approximately 1.2 mm, while much smaller microspheres were obtained using the emulsification technique, ranging in size from 8 to 17 µm. The trehalose was added as a cryoprotectant to improve the survival rate of probiotics in freeze-dried alginate carriers. The encapsulation efficiency for both of the methods applied, the emulsification and the extrusion technique, was high, with levels of 90% and 87%, respectively. The obtained results showed that the production method of probiotic-loaded microspheres influence the bacterial viability. The better strain survival in the developed systems was achieved in the case of microspheres produced by the emulsification (reduction in bacterial cell viability in the range of 1.98–3.97 log in silica oleogel and 2.15–3.81 log in sucragel oleogel after 7 and 30 days of storage) than by the extrusion technique (after a week and a month of oleogel storage, the decrease in cell viability was 2.52–4.52 log in silica oleogel and 2.48–4.44 log in sucragel oleogel). Full article

Adsorption is one of the most promising strategies for heavy metal removal. For Hg(II) removal, mineralized Ca-based shell-type self-assembly beads (MCABs) using alginate as organic polymer template were synthesized in this work. The adsorbent preparation consists of gelation of a Ca-based spherical polymer template (CAB) and rate-controlled self-assembly mineralization in bicarbonate solution with various concentrations. The comparative study demonstrates that 1% (MCAB-1) is the optimal concentration of bicarbonate. Based on this condition, the maximum adsorption capacity (48 ± 4 mg/g) of MCAB-1 was observed at pH = 5 in a batch test, which was 2.67 times more than that of the unmodified one, CAB, at 18 ± 1 mg/g. Long-duration (10 h) adsorption tests showed that MCAB-1 exhibited remarkable performance stability and anti-wear ability (43.2% removal efficiency and 74.3% mass retention, compared to 2.7% and 38.6% for CAB at pH = 3, respectively). The morphology determination showed that a shell-type porous amorphous carbonate layer was formed at the surface of the organic polymer template by rate-controlled self-assembly mineralization. This transition not only promotes the pore structure and activated cation binding functional sites, but also improves the anti-wear ability of materials effectively. Full article