Sodium Alginate Beads Research Articles

Entrapment of multi-scale structure of alginate beads stabilized with cellulose nanofibrils for potential intestinal delivery of lactic acid bacteria

Soybean cellulose nanofibrils (SCNFs) were formed by autoclave-enzymatic hydrolysis combined with ball milling. SCNFs were blended with sodium alginate (SA) to encapsulate lactic acid bacteria (LAB) through inotropic gelation. The effect of SCNFs on the multiscale structure of SA beads, leading to changes in the survival and release of LAB during simulated digestion, was investigated. Microscopy and rheological testing indicated that SCNF10–30 was well-dispersed in the SA paste in the form of interlaced nanofibrils, and could reduce the deformation of the paste under stress by 47.31 %. Multiscale structural analysis indicated SCNF10–30 not only increased the immobilized water of SA beads by 15.59 % by coordinating calcium, but also regulated the in situ-assembly of SA beads, including an increase in the scale of dimers from 6.73 nm to 8.32 nm and improved arrangement, thus forming a dense gel network. LAB viability of SA-SCNF10–30 in simulated digestion was increased by 1.3 log CFU/g compared to SA beads. Cellulose nanofibrils improved gastrointestinal survival and controlled release of LAB better than fiber rods. This study provides a strategy to regulate the multiscale structure of SA beads through nanofibrils to enable stabilization and sustainable release of LAB in gastrointestinal fluids.

Wastewater treatment process using immobilized microalgae.

Microalgae biomass products are gaining popularity due to their diverse applications in various sectors. However, the costs associated with media ingredients and cell harvesting pose challenges to the scale-up of microalgae cultivation. This study evaluated the growth and nutrient removal efficiency (RE) of immobilized microalgae Tetradesmus obliquus in sodium alginate beads cultivated in swine manure-based wastewater compared to free cells. The main findings of this research include (i) immobilized cells outperformed free cells, showing approximately 2.3 times higher biomass production, especially at 10% effluent concentration; (ii) enhanced organic carbon removal was observed, with a significant 62% reduction in chemical oxygen demand (383.46-144.84 mg L-1) within 48 h for immobilized cells compared to 6% in free culture; (iii) both immobilized and free cells exhibited efficient removal of total nitrogen and total phosphorus, with high REs exceeding 99% for phosphorus. In addition, microscopic analysis confirmed successful cell dispersion within the alginate beads, ensuring efficient light and substrate transfer. Overall, the results highlight the potential of immobilization techniques and alternative media, such as biodigested swine manure, to enhance microalgal growth and nutrient RE, offering promising prospects for sustainable wastewater treatment processes.

New insight into multi-functional MOG@COP/SA beads for co-adsorption and mono-detection in CTC-Cr(Ⅵ) co-contamination system and efficient anti-counterfeiting

Co-contamination of antibiotics and heavy metals in water environment has provoked considerable toxicological concerns. Meantime, residue detection of heavy metals as well as national anti-counterfeiting safety also have driven attempts in wastewater treatment. In this paper, a core–shell hybrid MOG@COP is designed with behaviors superior to pristine components by combining a Zr-based metal–organic gel and a guanidine-based covalent organic polymer, for co-adsorption and mono-detection in chlortetracycline hydrochloride (CTC)-Cr(Ⅵ) co-contamination system and efficient anti-counterfeiting. In single/binary system, the adsorption capacities of CTC and Cr(Ⅵ) behave as 133.69 and 63.45 mg·g−1/181.82 and 64.47 mg·g−1, and the high sensitivity and low detection limit of Cr(Ⅵ) render as 1.46*105 M−1 and 0.20 μM/1.49*102 M−1 and 0.63 mM, respectively. In addition, to solve the powder shortcomings of easy agglomeration and difficult recycling, MOG@COP is fixed into sodium alginate (SA) matrix to fabricate MOG@COP/SA beads, yielding reinforced adsorption performance of CTC/Cr(Ⅵ) in both single system (152.91/92.25 mg·g−1) and binary system (174.83/75.30 mg·g−1). More importantly, a self-constructed adsorption-detection-anti-counterfeiting (ADA) platform is ingeniously developed with the MOG@COP/SA beads as the backfills for continuously processing CTC-Cr(Ⅵ) co-contaminated water, realizing real-time visualization of Cr(Ⅵ) adsorption process and optical anti-counterfeiting protection. In conclusion, this work is expected to not only trigger the reasonable design of the core–shell hybrid MOG@COP/SA beads with versatile performances of simultaneous luminescence monitor, capture and anti-counterfeiting, but also allow the original exploration for all-in-one platform.

Immobilization of multilayer sodium alginate/polysaccharide antibacterial material composite beads as glufosinate controlled release matrices

To find a new way to slow down the release of glufosinate (GA) pesticide and to solve the susceptibility to decomposition by soil microorganisms, a series of novel antibacterial polysaccharide-based sustained release beads (PSRB) were prepared. The PSRB was prepared by immobilization of GA loaded polysaccharide-based chitosan quaternary ammonium salt (PS-HACC) microcapsules in the core and layers of the multilayer sodium alginate beads. The PSRB was characterized by FI-IR spectroscopy, XRD, SEM, and BET to reveal their composition and surface morphology. The optimal conditions of the slow release beads were as follows, the concentration of Ca2+, pH, temperature and the coating layer number was 0.1 mol/L, 7, 25 °Cand 3, respectively. The kinetic study showed that the slow release of PSRB was in accordance with the Higuchi kinetic model, and the FI-IR and XRD analyses revealed that the PS-HACC and GA were successfully cross-linked to the PSRB. BET showed that PSRB were greater than PSRB3 at surface area, pore volume and pore size. Inhibition circles experiments demonstrated that WPSRB3 has good antibacterial activity. The weed control in soybean with PSRB3 application is perfect and the weed control cycle is long. Therefore, this technology can provide a potential way to control GA release, improve utilization efficiency, reduce pesticide use and environmental pollution, and at the same time, provide a potential way to achieve ecological agriculture.

Study on Biosorption of Lead (II) and Manganese (II) from Aqueous Solutions Using Sodium Alginate and Pleurotus ostreatus (Oyster Mushroom) Beads

Study on Biosorption of Lead (II) and Manganese (II) from Aqueous Solutions Using Sodium Alginate and Pleurotus ostreatus (Oyster Mushroom) Beads

Enhanced arsenic removal using biochar immobilized bacteria encapsulated in polyvinyl alcohol-sodium alginate beads: Fabrication, optimization and performance evaluation

Arsenic ranks first on the Substance Priority List of the Agency for Toxic Substances and Disease Registry and causes a wide range of health problems, including cancer and even death. The present work was focused on the removal of arsenic using bacteria, Proteus alimentorum strain TY6 and Pseudomonas aeruginosa strain K7Pb, immobilized on peanut shell biochar [0.05 % (w/v)] and encapsulated in polyvinyl alcohol (PVA) – sodium alginate (SA) beads crosslinked with calcium chloride (CaCl2). The maximum removal efficiency obtained was 92.29 ± 0.51 % and 93.63 ± 0.09 % for As(V), using beads of K7Pb and K7Pb + TY6 respectively, whereas for As(III), it was 91.71 ± 0.51 % with TY6 and 93.35 ± 0.05 % for KP7b + TY6, at pH 7 at 30 °C. Surface morphology was characterized by scanning electron microscopy and energy-dispersive x-ray analysis. This study revealed that the encapsulated bacteria immobilized on biochar were more effective than the free-cell and bacteria immobilized on biochar. It was also found that the beads could be reused effectively for five cycles (for K7Pb and TY6) and eight cycles (for K7Pb + TY6) before their removal efficiency reduced to below 80 %.

Biodegradation of endocrine disrupting compounds from the wastewater by the immobilized indigenous bacteria

Abstract4‐tert‐octyl phenol is one of the important endrocrine‐disrupting compounds and is considered a major health hazard. A total of six isolates degraded 4‐tert‐octylphenol, and the strains Bacillus velezensis LG16 and Pseudomonas aeruginosa AC20 exhibited maximum 4‐tert‐octylphenol degradation. Co‐culture of these two strains improved 4‐tert‐octylphenol degradation from the wastewater. One variable at a time approach showed that 40°C incubation temperature, pH 8.0, and an initial 4‐tert‐octylphenol (60 mg/L) influenced biodegradation. The bacterial strains were immobilized in sodium alginate beads, and improved biodegradation was achieved. The biocatalytic process mediated by the immobilized cells was optimized by a statistical approach (two‐level full factorial design and response surface methodology). In a two‐level factorial model, 4‐tert‐octylphenol degradation varied from 1.1% to 55.2%. The 4‐tert‐octylphenol degradation was maximum at pH 6, 0.01 mg/L 4‐tert‐octylphenol, and 10 mg/L glucose with 20 g beads/L. ANOVA revealed that the designed model was statistically significant (p = 0.0310). A central composite design was used to analyze the interactive effect of significant variables and to explore the optimum conditions for 4‐tert‐octylphenol degradation by immobilized bacteria. The maximum phenol degradation was observed (97.4%) at pH 7.0, 0.06 4‐tert‐octylphenol, and 13.75 g sodium alginate beads/L. ANOVA showed that the designed model was statistically significant (p = 0.0091). The designed CCD model, the correlation coefficient value, and the lack of fit value showed that the designed CCD model was significant. The immobilized bacterial cells could more effectively degrade 4‐tert‐octylphenol than free bacterial cells. The high degradation potential indicated its application in degrading 4‐tert‐octylphenol from wastewater under optimized conditions.

Composites of sodium alginate based - Functional materials towards sustainable adsorption of benzene phenol derivatives - Bisphenol A/Triclosan

The present study evaluates the adsorption efficiency of low-cost carbonaceous adsorbents as fly ash (FA), saw dust biochar (SDB) (untreated and alkali - treated), live/dead pulverized white rot fungus Hypocrea lixii biomass encapsulated in sodium alginate (SA) against the commercially available activated carbon (AC) and graphene oxide (GO) SA beads for removal of benzene phenol derivatives - Bisphenol A (BPA)/triclosan (TCS). Amongst bi - and tri - composites SA beads, tri-composite beads comprising of untreated flyash - dead fungal biomass - sodium alginate (UFA - DB - SA) showed at par results with commercial composite beads. The tri - composite beads with point zero charge (Ppzc) of 6.2 was characterized using FTIR, XRD, surface area BET and SEM-EDX. The batch adsorption using tri - composite beads revealed removal of 93% BPA with adsorption capacity of 16.6 mg/g (pH 6) and 83.72% TCS with adsorption capacity of 14.23 mg/g (pH 5), respectively at 50 ppm initial concentration with 6 % adsorbent dose in 5 h. Freundlich isotherm favoring multilayered adsorption provided a better fit with r2 of 0.9674 for BPA and 0.9605 for TCS respectively. Intraparticle diffusion model showed adsorption of BPA/TCS molecules to follow pseudo - second order kinetics with boundary layer diffusion governed by first step of fast adsorption and intraparticle diffusion within pores by second slow adsorption step. Thermodynamic parameters (ΔH°, ΔS°, ΔG°) revealed adsorption process as exothermic, orderly and spontaneous. Methanol showed better desorbing efficiency leading to five cycles reusability. The phytotoxicity assay revealed increased germination rate of mung bean (Vigna radiata) seeds, sprinkled with post adsorbed treated water (0 h, 5 h and 7 h) initially spiked with 50 ppm BPA/TCS. Overall, UFA - DB - SA tri - composite beads provides a cost effective and eco - friendly matrix for effective removal of hydrophobic recalcitrant compounds.

Cover Image, Volume 62, Issue 8

A novel three‐component covalent organic polymer (COP) named SLEL‐6 was prepared based on Schiff base chemistry through a multi‐component method for ciprofloxacin removal from an aqueous solution. It could be embedded in sodium alginate (SA) to obtain spherical COP/SA composite beads (SLEL‐6/SA beads) with enhanced adsorption ability and boosted recyclability. Details are found in the article from Yangxue Li and colleagues. DOI: 10.1002/pol.20230258 image

Efficient removal of E. coli from wastewater by novel phytofabricated nano-zinc using antibacterial potential, kinetic studies, and response surface methodology

The present investigation explores the antibacterial potential of novel ZnO-NPs synthesized from Acacia nilotica pods extract and immobilized onto sodium alginate beads to control bacterial pollution in wastewater. Phenolics and flavonoids were major phytoconstituents acting as capping, reducing, and stabilizing agents. UV–Vis analysis showed strong absorption band at 340 nm. XRD and TEM revealed hexagonal crystalline structure for zincite of average particles diameter 33.87 and 32.74 nm, respectively. FTIR demonstrated several bands with functional groups (O–H, C-H, C = O, C = C, and C–O–C) involved in ZnO-NPs synthesis. SEM images showed NPs surface completely colonized by E.coli, while EDX spectrum showed signals for zinc (52.94%) and oxygen (26.58%) confirming NPs purity. Adhesion capacity studies revealed ZnO-NPs potential (0.5 g) to remove E.coli after 120 min. Kinetic and isotherm studies indicated that pseudo-second-order model and Freundlich isotherm were best fit describing adhesion mechanism. Electrostatic attraction between negatively charged E.coli and positively charged ZnO-NPs was followed by generation of H2O2 leading to cell apoptosis. Adhesion optimization using Box–Behnken design under response surface methodology was 99.8% at disinfectant dose 30 g/L, contact time 6 h, and E.coli concentration 150 × 107 cfu/mL. For application, real wastewater was treated with removal 98.2%, 97.2%, and 96.5% for total coliform, fecal coliform, and E.coli, respectively, after 6 h. ZnO-NPs showed sustainable efficiency during four consecutive cycles of treatment. The study concluded the efficiency, eco-friendly and cost-effectiveness of phytofabricated ZnO-NPs as disinfectants for wastewater and recommended future studies on large scale for possible wastewater reuse in safe unrestricted irrigation.

A novel approach for adsorption of organic dyes from aqueous solutions using a sodium alginate/titanium dioxide nanowire doped with zirconium cryogel beads.

The presence of organic dyes in wastewater raises significant environmental and human health concerns, owing to their high toxicity. In light of this, a novel adsorbent material with porous cryogel architecture was developed and employed for the effective removal of organic dyes from an aqueous solution. Initially, a titanium dioxide nanowire doped with zirconium HZTO was synthesized by the hydrothermal process. Subsequently, the beads (SA/HZTO) of sodium alginate and HZTO were successfully prepared through a cross-linking process, employing Ca2+ ions as the crosslinking agent. Structural analysis of SA/HZTO beads was performed using FTIR, SEM, and EDX techniques. We systematically examined the impact of different conditions, including the initial dye concentration, pH, contact time, and adsorbent dosage, on the adsorption process. Batch experiments, both in signal and binary systems, were conducted to rigorously assess the dye adsorption capabilities. Kinetic modeling revealed that the adsorption process adhered to the pseudo-second-order kinetic model. Remarkably, the prepared beads exhibited impressive adsorption capacities of 26 and 29mg/g toward methylene blue (MB) and safranin (SF), respectively. SA/HZTO beads have demonstrated excellent adsorption properties, offering a promising avenue for the development of low-cost, efficient, and reusable adsorbent to remove dyes from wastewater.

Insulin Conformation Changes in Hybrid Alginate-Gelatin Hydrogel Particles.

There is a strong need to develop an insulin delivery system suitable for oral administration and preserving natural (α-helix) insulin conformation. In this work, we fabricated alginate-gelatin hydrogel beads for insulin encapsulation. Altering matrix composition and crosslinking agents has resulted in various surface morphologies and internal spatial organization. The structures of the insulin-loaded matrices were studied using optical and field emission electronic microscopy. We use FTIR spectroscopy to identify insulin conformation changes as affected by the hydrogel matrices. It was found that blended alginate-gelatin matrices demonstrate better encapsulation efficiency and stronger swelling resistance to a simulated gastric environment than sodium alginate beads crosslinked with the CaCl2. FTIR measurements reveal conformation changes in insulin. It is also confirmed that in the presence of gelatin, the process of insulin fibrinogenesis ceases due to intermolecular interaction with the gelatin. Performed molecular modeling shows that dipole-dipole interactions are the dominating mechanism that determines insulin behavior within the fabricated matrix.

Synthetic Seed Production and Slow Growth Storage of In Vitro Cultured Plants of Iris pallida Lam.

Iris pallida Lam. is traditionally cultivated in Italy to sell its rhizomes to perfume-producing industries and is particularly sought-after because of its high content of irones, ketone compounds responsible for the violet smell of the orris essence. One of the critical aspects of its cultivation is the propagation method, performed by subdividing and replanting sections of the rhizome, which leads to the sacrifice of salable material. A solution is provided via in vitro propagation using the somatic embryogenesis technique, an effective method that allows the production of plants without the use of the rhizome. To facilitate the scale up of the activities of micropropagation companies, the method of slow growth storage (SGS) for orris plantlets and a somatic embryo encapsulation technique were developed for the first time. Orris plantlets were placed at 4 °C in the dark for 30, 60, 90 and 120 days and monitored 7 and 30 days after treatment. Synthetic seeds were obtained by encapsulating somatic orris embryos in sodium alginate beads, which were stored for 14 and 28 days at 4 °C and 24 °C. The results showed that it is possible to cold-preserve orris plantlets for up to 90 days without significant damages and that orris synthetic seeds can be produced and stored for a short-to-mid-term period. These conservation techniques can be useful for germplasm conservation and can also be integrated in the micropropagation cycle of orris, helping to solve issues related to the traditional propagation method.

A carbon dots-MnO2 nanosheet-based turn-on pseudochemodosimeter as low-cost probe for selective detection of hazardous mercury ion contaminations in water

Mercury is a highly hazardous element due to its profound toxicity and wide abundance in the environment. Despite the availability of various fluorimetric detection tools for Hg2+, including organic fluorophores and aptasensors, they often suffer from shortcomings like the utilization of expensive chemicals and toxic organic solvents, multi-step synthesis, sometimes with poor selectivity and low sensitivity. Whereas, biomass-derived fluorophores, such as carbon dots (CDs), present themselves as cost-effective and environmentally benign alternatives that exhibit comparable efficacy. Herein, we report a reaction-driven sensing assembly based on CDs, MnO2 nanosheets, and hydroquinone monothiocarbonate (HQTC) for the detection of Hg2+ ions, which relies on the formation of a CDs-MnO2 FRET-conjugate, resulting in the quenching of the intrinsic fluorescence of CDs. In a pseudochemodosimetric approach, the thiophilic nature of mercury was utilized for in-situ generation of the reducing species, hydroquinone from HQTC, resulting in the reduction of MnO2 nanosheets, the release of fluorescent CDs back to the solution. The low limit of detection (LOD) was achieved as 2 ppb (0.01 μM). The probe worked efficiently in real water samples like sea, river with good recovery of spiked Hg2+ and in some Indian ayurvedic medicines as well. Furthermore, solid-phase detection with sodium alginate beads demonstrated the ability of this cost-effective sensing assembly for onsite detection of Hg2+ ions.

Expression and Immobilization of Tannase for Tannery Effluent Treatment from Lactobacillus plantarum and Staphylococcus lugdunensis: A Comparative Study.

Agro-industrial discharges have higher concentrations of tannins and have been a significant cause of pollution to water bodies and soil surrounding the agro-industries. So in this study, toxic tannic acid is into commercially valuable gallic acid from the tannery effluent using immobilized microbial tannase. Tannase genes were isolated from Lactobacillus plantarum JCM 1149 (tanLpl) and Staphylococcus lugdunensis MTCC 3614 (tanA). Further, these isolated tannese genes were cloned and expressed in BL 21 host using pET 28a as an expression vector, andimmobilized in sodium alginate beads. Vegetable tannery effluent was treated by tannase-immobilized beads at 25°C and 37°C, where liberated gallic acid was analyzed using TLC and NMR to confirm the tannin reduction. Further, both immobilized tannases exhibited excellent reusability up to 15 cycles of regeneration without significant reduction in theiractivity. Moreover, we also showed thatimmobilized tannases tanLpl and tanA activity remained unaffected compared to the free enzyme in the presence of metal ions. Further, tanA activity remained unaffected over a wide range of pH, and tanLpl showed high thermal stability. Thus, immobilized tannase tanLpl and tanA provide a possible solution for tannery effluent treatment depending upon industry requirements and reaction composition/effluent composition, one can choose a better-immobilized tannase among the two as per the need-based requirement.

Preparation and Characterization of Sodium Alginate Based Composite Beads for Manganese Removal

The main objective of this study was to characterize and investigate the performance of sodium alginate (SA)-based composite beads as adsorbents for manganese removal from the aqueous solution. In this study, 2% (w/v) of sodium alginate solution was prepared. The SA beads, SA-PCC (SA-P) beads, SA-BMnO (SA-B) beads, and SA-PCC-BMnO (SA-PB) beads were formed by mixing with ionic gelation in a crosslink solution of calcium chloride (CaCl2). The composite beads were characterized using FESEM and thermogravitmetry analysis (TGA). According to FESEM micrographs, all the adsorbents were spherical in shape, with an average diameter of 1.40 mm to 1.50 mm. The results of TGA demonstrated that SA-PB beads had improved thermal stability and exhibited the highest manganese removal efficiency, with a percentage of removal of 96.14%.

PREPARATION OF HEALTH BENEFICIAL PROBIOTIC SOYA ICE -CREAM AND EVALUATION OF QUALITY ATTRIBUTES

Probiotic soya ice cream was prepared by using food grade bacteria Lactobacillus paracasei S1(MF443873) and Lactobacillus rhamnosus KC6 (MF443875). Bacteria have been encapsulated in milk and sodium alginate beads to improve their viability in soya ice -cream. Viable cell number of entrapped probiotic isolates was observed with calcium chloride concentration of 0.1M at pH 7.0, hardening time of 8h. Morphological characterization of microencapsulated beads was done by using SEM. Probiotic soy ice-cream was stored at -20oC for 30 days and was investigated for sensory qualities, microbial count and physicochemical characteristics. Microencapsulated probiotic ice-cream was found more stable during storage as compared to those containing free probiotic microorganisms. As far as physico-chemical characteristics of probiotic enriched soy ice-cream is concerned, though changes in quality attributes viz. pH, ascorbic acid, lactic acid, total soluble solid and antioxidant content during storage interval have been observed but these changes were statistically non- significant.

Biological Control for Solanum melongena L. in Sustainable Agriculture.

The environment and ecosystem were disrupted by the extensive use of fertilizers and pesticides which are harmful to humans and animals. Nature unfolds a biological response to overcome the different types of hazardous agrochemicals, in the form of microorganisms which have the efficiency to encourage plant growth without disturbing the environment. We conducted a biological approach to control phytopathogenic agents by plant growth-promoting rhizobacteria (PGPR), capable of restraining the devastation by phytopathogen. Pseudomonads can cling to soil particles, motile, prototrophic, and antibiotic synthesis along with the production of hydrolytic enzymes. Pseudomonas fluorescens extracted from the soils of Kerala were subjected to the identification of genes that have the phytostumillatory effect. These bacteria were immobilized using sodium alginate beads and applied to the soil where Solanum melongena (L.) was planted and the growth was compared with plants treated with cyanobacteria Spirulina platensis and NPK. The plants treated with PGPR showed high potential in growth-promoting characters when compared to cyanobacteria and NPK. P. fluorescens is an intense bio-agent to use in the field of agriculture because of its multifaceted utility.

Experimental and computational study of a packed-bed bioreactor for the continuous production of succinic acid

In this work we present a packed-bed bioreactor system packed, with immobilised cells in sodium alginate beads, for the biological conversion of glycerol to succinic acid.

In situ chlorpyrifos (CPF) degradation by Acrobeloides maximus: Insights from chromatographic analysis

The objective of this study was to evaluate the efficiency of nematodes in zooremediation of chlorpyrifos (CPF), an organophosphate pesticide. The nematode population Acrobeloides maximus (A. maximus) was employed for bioremediation, converting CPF into non-toxic residues. Optimal growth conditions for mass production of A. maximus were achieved by maintaining a temperature of 25 °C, pH 8, and supplementing the culture medium with plant nutrients. The nematodes were then immobilized within sodium alginate beads. The efficacy of the degradation process was assessed using various analytical techniques, including UV-Visible spectroscopy, HPTLC, FTIR, and LC-MS, confirming the successful breakdown of CPF. The bioreactor demonstrated a complete degradation efficiency of CPF exceeding 99%. Additionally, LC-MS analysis was conducted to elucidate the degradation pathway based on the formation of intermediates. These results underscore the potential of A. maximus as a sustainable organism for addressing environmental contamination arising from CPF pesticide.