Gellan Gum Concentration Research Articles

Fish Gelatin-Based Flexible and Self-Healing Hydrogel Modified by Fe2(SO4)3.

The application of fish gelatin (FG) is limited due to its poor mechanical properties and thermal stability, both of which could be significantly improved by gellan gum (GG) found in previous research. However, the FG/GG composite hydrogel was brittle and easily damaged by external forces. It was found that the composite hydrogel with Fe2(SO4)3 showed good flexibility and self-healing properties in the pre-experiment. Thus, the synergistic effect of FG, GG and Fe2(SO4)3 on the mechanical properties of the composite hydrogel was investigated in this study. According to one-way experiments, response surface tests and Texture Profile Analysis, it was found that under the optimum condition of FG concentration 186.443 g/L, GG concentration 8.666 g/L and Fe2(SO4)3 concentration 56.503 g/L, the springiness of the composite cylindrical hydrogel with the height of 25 mm formed in 25 mL beakers (bottom diameter 30 mm) was 7.602 mm. Determination of the rheological properties, compression performance, adhesive performance and self-healing properties showed that the composite hydrogel had good thermal stability, flexibility and self-healing properties with good adhesion, skin compliance and compressive strength, and it was easy to remove. The composite hydrogel showed strong antimicrobial activity against A. salmonicida and V. parahaemolyticus. All hydrogels showed a uniform and porous structure. The 3D structure of the composite hydrogel was much looser and more porous than the pure FG hydrogel. The flexible and self-healing composite hydrogel with some antimicrobial activity is suitable for the development of medical dressings, which broadens the applications of the composite hydrogel.

Encapsulation of Lactiplantibacillus plantarum with casein-gellan gum emulsions to enhance its storage, pasteurization, and gastrointestinal survival

Probiotics serve a very important role in human health. However, probiotics have poor stability during processing, storage, and gastrointestinal digestion. The gellan gum (GG) is less susceptible to enzymatic degradation and resistant to thermal and acidic environments. This study investigated the effect of casein (CS)-GG emulsions to encapsulate Lactiplantibacillus plantarum CICC 6002 (L. plantarum CICC 6002) on its storage stability, thermal stability, and gastrointestinal digestion. L. plantarum CICC 6002 was suspended in palm oil and emulsions were prepared using CS or CS-GG complexes. We found the CS-GG emulsions improved the viability of L. plantarum CICC 6002 after storage, pasteurization, and digestion compared to the CS emulsions. In addition, we investigated the influence of the gellan gum concentration on emulsion stability, and the optimal stability was observed in the emulsion prepared by CS-0.8% GG complex. This study provided a new strategy for the protection of probiotics based on CS-GG delivery system.

Gellan Gum grafted poly acrylic acid hydrogels: Synthesis and adsorption studies

Gellan Gum (GG) grafted poly-acrylic acid (GG-g-pAAc) hydrogels of different composition were synthesized by changing the concentration of GG through free radical polymerization. The hydrogels were characterized through SEM, TGA, and FTIR. The FTIR spectra confirmed the grafting of GG into the network of polyacrylic acid and evidenced the GG-g-pAAc formation. The rough surface nature of the hydrogels was elaborated through SEM analysis provided the information about the materials to be utilized for removal purpose. The thermal stability was confirmed by TGA analysis and the hydrogels were found stable upto a high temperature range. With an efficiency of 96%, Basic Orange-2 dye (BO-2) was successfully removed from wastewater using synthesized hydrogels as an adsorbent. The adsorption parameters were calculated using a number of different kinetic models. According to the findings, the pseudo-second order kinetics model best suited to the kinetics data, while the Langmuir isotherm provided the most comprehensive explanation of the process of adsorption. BO-2 was removed to the greatest extent (257.5 mg/g). Additionally, the results showed that the adsorption process on synthesized hydrogels was exothermic with values of ΔH = −13.2, −219.4 and −12.9 kJ/mol for pAAc, 10%GG-g-pAAc, and 20%GG-g-pAAc respectively. The adsorption process is spontaneous, with negative values of ΔG = −8.2, −214.4 and −7.947 kJ/mol for pAAc, 10%GG-g-pAAc and 20%GG-g-pAAc at 293K, respectively. The adsorption process on synthesized hydrogels showed no dis-orderness with negative values of ΔS = −17.2, −461.16 and −16.42 kJ/mol for pAAc, 10%GG-g-pAAc and 20%GG-g-pAAc, respectively.

Biopharmaceutical distribution and pharmacodynamic evaluation of intra nasal in-situ gel of Lamotrigine for brain targeted drug delivery

Background: The present research investigates the nasal delivery of Lamotrigine by incorporating it into a natural in-situ gelling system. Additionally, the retention of the drug in the nasal cavity was enhanced by employing the natural mucoadhesive polymer locust bean gum (LBG). A preliminary investigation was conducted to determine the optimal concentration of gellan gum. The dosage of the drug was calculated using the Robinson Erikson equation. The central composite design was utilized to optimize the influence of individual variables such as gellan gum and locust bean gum on various responses, including gelation time, gel viscosity, mucoadhesive strength, and the time taken for the drug to release half of its initial concentration (t50). The goal of the current study was to evaluate the in-vivo effectiveness of intra nasal in-situ gel of Lamotrigine. Methodology: The pharmacokinetic and tissue distribution studies were carried out to evaluate the brain targeting efficiency of lamotrigine. Blood samples and tissues of various vital organs like brain, liver, kidneys and heart were obtained at different time intervals, plasma and tissue concentration of Lamotrigine was estimated by reverse phase HPLC. Results: According to the pharmacokinetic analysis, Cmax and AUC0-α is found to be significantly more (P<0.05) for nasal route compared to oral route. In comparison to the oral route, Cmax and AUC0-α was 7 and 6.5 folds more for IN route. The absolute bioavailability was found to be 159.07%. with regard to the oral group, minimal drug was present in any of the other tissue samples. In the pharmacodynamic data also the formulation through nasal route showed a significant difference compared to oral route (pure drug suspension) delivery in PTZ induced study. Keywords: Lamotrigine, in-vivo study, tissue distribution, pharmacodynamics

Scalable and Quench-Free Processing of Metal Halide Perovskites in Ambient Conditions

With the rise of global warming and the growing energy crisis, scientists have pivoted from typical resources to look for new materials and technologies. Perovskite materials hold the potential for making high-efficiency, low-cost solar cells through solution processing of Earth-abundant materials; however, scalability, stability, and durability remain key challenges. In order to transition from small-scale processing in inert environments to higher throughput processing in ambient conditions, the fundamentals of perovskite crystallization must be understood. Classical nucleation theory, the LaMer relation, and nonclassical crystallization considerations are discussed to provide a mechanism by which a gellan gum (GG) additive—a nontoxic polymeric saccharide—has enabled researchers to produce quality halide perovskite thin-film blade coated in ambient conditions without a quench step. Furthermore, we report on the improved stability and durability properties inherent to these films, which feature improved morphologies and optoelectronic properties compared to films spin-coated in a glovebox with antisolvent. We tune the amount of GG in the perovskite precursor and study the interplay between GG concentration and processability, morphological control, and increased stability under humidity, heat, and mechanical testing. The simplicity of this approach and insensitivity to environmental conditions enable a wide process window for the production of low-defect, mechanically robust, and operationally stable perovskites with fracture energies among the highest obtained for perovskites.

FORMULATION AND CHARACTERISATION OF GASTRORETENTIVE IN SITU GEL LOADED WITH GLYCYRRHIZA GLABRA L. EXTRACT FOR GASTRIC ULCER

Objective: The study aimed to formulate and evaluate the gastroretentive in situ gelling system of Glycyrrhiza glabra L. extract to increase the gastric residence time and provide sustained release of the drug, thereby avoiding disadvantages such as frequent dosing, patient non-compliance and low bioavailability. Methods: The in-situ gel was prepared by pH-triggered gelation method by using sodium alginate and gellan gum as polymers, sodium citrate as a crosslinking agent, and calcium carbonate as a floating agent. Formulation and optimization of in situ gels were achieved by 32 factorial design by using Design-Expert Software to determine the influence of independent variables such as concentration of sodium alginate and gellan gum on viscosity, gel strength, the onset of flotation, and drug release at 12 h. Results: The viscosity, gel strength, onset of flotation and drug release at 12h of optimized formulation were found to be 568.89 cps, 42.91 sec, 53.17 sec and 82.69%, respectively. The floating duration of all in-situ gels was found to be more than 12 h. All the formulations showed drug content in the range of 83.55% to 95.28%. The in vitro release profile of the drug extract from all the formulations appeared to follow the Higuchi model, which concludes that the drug release was controlled by diffusion mechanism. The FTIR study indicates no chemical incompatibility between drug extract and other excipients. Conclusion: Hence, a novel gastroretentive in situ gelling system of Glycyrrhiza glabra L. could be prepared for sustained oral delivery to increase patient compliance with reduced dosing frequency and increased residence time of the drug in the stomach.

Ion-activated In Situ Gel of Gellan Gum Containing Chrysin for Nasal Administration in Parkinson's Disease.

This study focused on creating an innovative treatment approach for Parkinson's disease (PD), a progressive neurodegenerative condition characterized by the loss of specific neurons in the brain. The research aimed to develop a nasal gel using gellan gum containing a complex of chrysin with hydroxypropyl-β-cyclodextrin (HP-β-CD) to enhance the drug's solubility and stability. The formulation process involved utilizing central composite design (CCD) to optimize the concentrations of gellan gum and HPMC E5, with viscosity and mucoadhesive strength as key factors. The resulting optimized In Situ gel comprised 0.7% w/v gellan gum and 0.6% w/v HPMC E5, exhibiting desirable viscosity levels for both sol and gel states, along with robust mucoadhesive properties. The formulated gel underwent comprehensive evaluation, including assessments for gelation, drug content, in vitro drug release, ex vivo permeation, and histopathology. The findings demonstrated superior drug release from the In Situ gel compared to standalone chrysin. Ex vivo studies revealed effective drug permeation through nasal mucosa without causing harm. Moreover, experiments on neuronal cells exposed to oxidative stress (H2O2- induced) showcased significant neuroprotection conferred by chrysin and its formulations. These treatments exhibited notable enhancements in cell viability and reduced instances of apoptosis and necrosis, compared to the control group. The formulations exhibited neuroprotective properties by mitigating oxidative damage through mechanisms, like free radical scavenging and restoration of antioxidant enzyme activity. In conclusion, this developed In situ gel formulation presents a promising novel nasal delivery system for PD therapy. By addressing challenges related to drug properties and administration route, it holds the potential to enhance treatment outcomes and improve the quality of life for individuals with Parkinson's disease.

The effects of gellan gum concentration on electrospinning and degradation of flexible, crosslinker-free scaffolds for bone tissue engineering

Low acyl type gellan gum (GG) is a biocompatible gelling agent with lower degradation rates compared to its high acyl counterpart. This study investigated the hypothesis whether the incorporation of various low acyl GG concentrations into a constant concentration of poly(vinyl alcohol) (PVA) would facilitate the electrospinning towards the production of stable nanofibrous PVA-GG membranes, and how thermal treatment would affect the degradation rate of the membranes rendering them suitable as flexible scaffolds for bone tissue engineering and avoiding crosslinking agents. All compositions displayed fiber diameters ranging from 70 to 200 nm. Thermally treated membranes indicated a mass loss of 20–32 %, while non-treated ones 32–54 %, with the higher GG concentrations exhibiting lower degradation rates, and swelling capacity of at least 500 %. Rheological analysis illustrated differences in gelling capacity, ranging from fluid-like to critical gelation state with increasing GG content, with G′ values ranging between 3.5 ± 0.5 Pa for the lowest and 23.4 ± 1.5 for the highest GG concentration. Proliferation of strongly adhered pre-osteoblasts significantly increased over culture time. Osteogenic markers including alkaline phosphatase activity and calcium deposition were significantly upregulated compared to the control, and calcium secretion gradually increased up to three weeks, validating the capacity of the scaffolds to support osteogenesis.

Texture improvement and in vitro digestion modulation of plant-based fish cake analogue by incorporating hydrocolloid blends

Hydrocolloids have proven effective in improving the texture of surimi gels, yet their application in plant-based seafood analogues remains underexplored. This study aimed to develop a hydrocolloid blend comprising methylcellulose (MC), curdlan gum (CG), and high-acyl gellan gum (GG) to achieve a surimi-like texture in plant-based fish cakes (PBFC) made from brown rice and pea protein isolates. The research showcased that higher MC concentration boosted protein powder's heated oil holding capacity, while CG concentration increments lowered it. However, heated water holding capacity remained stable despite changes in MC and GG levels. Incorporating hydrocolloids elevated PBFC moisture content, decreasing expressible moisture and oil amounts with rising MC, CG and GG concentrations. PBFC hardness increased with higher hydrocolloid levels and was influenced by temperature, while springiness remained unaffected. GG helped maintain storage modulus (G′) during PBFC cooling at higher concentrations, whereas the opposite effect was observed for MC. Analytically, higher MC concentrations reduced protein digestibility, while increased GG concentrations appeared to enhance it. Microstructural analysis corroborated these findings, with more protein aggregates in PBFC containing 3.8% MC and fewer in PBFCs with 6% CG and 3% GG. Consumer evaluations indicated that PBFC formulated with 1% MC, 3% CG, and 1.5% GG matched the springiness of commercial surimi-tofu fish cake, though it received slightly lower overall liking scores. In conclusion, the combined use of these three hydrocolloids demonstrated the potential to enhance the physical properties of PBFC and modify protein digestibility, offering insights into the development of innovative plant-based seafood analogues.

Control of plant-based biopolymer composite gel texture: Combining potato proteins with different high acyl-low acyl gellan gum ratios

The impact of blending different kinds of gellan gum (GG) on the textural attributes of potato protein-based biopolymer composites was studied. The total potato protein concentration (10 wt%) and gellan gum concentration (3 wt%) of the composite gels was fixed but the ratio of HAGG (forms soft and elastic gel) to LAGG (forms hard and brittle gel) was varied (100:0 to 0:100). During cooling, HAGG set at a higher temperature than LAGG, due to differences in steric hindrance effects. As the LAGG content increased, the shear modulus, Young's modulus, and brittleness of the gels increased, while their water holding capacity decreased. There were no major differences in the nature of the molecular interactions between the proteins in composite gels formulated using different gellan gum ratios. The addition of an antifoaming agent significantly reduced the variability in the textural attributes of the gels and increased their gel strength, which was attributed to its ability to suppress bubble formation. Overall, our results suggest that the textural attributes of biopolymer composite gels can be controlled by using plant proteins in combination with a pair of polysaccharides with different gelling properties. This knowledge may aid in the formulation of soft solid plant-based foods with more desirable textural attributes, such as meat, seafood, or egg analogs.

Interactions between pea protein and gellan gum for the development of plant-based structures

Plant-based analogs have been developed to mimic foods from animal sources by using ingredients from vegetable sources. Among the strategies to produce plant-based structures is the gelation of mixtures between plant proteins and polysaccharides. In this study, our aim was to investigate gels of pea proteins and gellan gum with high protein concentration and the addition of salt (potassium and sodium chloride). In the first step, a qualitative mapping was performed to select pea protein and gellan gum concentrations to produce self-sustainable gels. After that, the effect of salt addition was investigated for the formulations containing 10–15 % (wt) pea protein and 0.5–1 % (wt) gellan gum. The results showed that the gels containing potassium ions were more rigid and less deformable, with lesser water loss by syneresis. The morphological analysis showed a spatial exclusion of pea protein from the gel network mainly structured by the gellan gum. While potassium ions led to a more compact network, calcium ions promoted higher pores in the structure. Depending on the composition, the mechanical properties of gels were similar to some products from animal sources. So, the information obtained from these gels can be applied to the structuring of formulations in the development of plant-based analogs.

The role of gellan gum in the selective flotation separation of fluorite from calcite: An experimental and molecular dynamics simulation study

Fluorite as the main source of fluorine generally coexists with calcite. The highly similar floatabilities and physicochemical properties make it tough to separate these two minerals. Herein, gellan gum (GG) was used as depressant to separate fluorite from calcite for the first time. Several experiments and tests were utilized to explain the inhibiting performance and mechanism of GG. Flotation experiments illustrated that GG displayed an outstanding depression performance for the calcite flotation, whereas it hardly depressed fluorite. Zeta potential analyses, surfaces wettability measurements and Fourier transform infrared (FTIR) indicated that GG strongly adhered onto calcite and prevented the NaOL from adhering on it. Adsorption amount measurements indicated that the GG adhered onto calcite with a higher amount compared to fluorite. X-ray photoelectron spectroscopy (XPS) tests pointed out that GG adsorbed onto calcite and fluorite surfaces by strong chemisorption and weak physisorption, respectively. Atomic force microscopy (AFM) measurements implied visually that GG adsorbed denser and stronger on the calcite than fluorite. Molecular dynamics (MD) simulations demonstrated that compared with fluorite, more GG adsorbed on the calcite surface due to the reaction between hydroxyl groups and the mineral surface, as evidenced by higher diffusion coefficient for water (Dwater) value, smaller interaction distance, and higher relative concentration of GG on the calcite surface. Therefore, GG could be employed as a promising flotation depressant in separating fluorite from calcite.

Development and characterization of 3D bioprintable and mechanically reinforced hydrogel based on gellan gum/methylcellulose/cellulose nanocrystals

Abstract3D bioprinting has appeared as a promising technology in the area of tissue engineering. Here, bioinks composed of various concentrations of gellan gum (GG), methylcellulose (MC) and cellulose nanocrystal (CNC) were developed for extrusion‐based bioprinting. Among the binary mixtures of GG/MC, the blend of 1% w/w GG and 4% w/w MC (1GG/4MC) provides the best property to further tailoring as bioink. For the ternary mixtures of GG/MC/CNC, 1GG/4MC/4% w/w CNC (1GG/4MC/4CNC) provide the best printability characteristic but not sufficient mechanical performance. Ionic crosslinking using various concentrations of salts including CaCl2, KCl and NaCl were applied to improve the mechanical strength. Both 1GG/4MC/4CNC/0.022% w/w CaCl2 (1GG/4MC/4CNC/0.022CaCl2) and 1GG/4MC/4CNC/0.075% w/w KCl (1GG/4MC/4CNC/0.075KCl) exhibit mechanical stability with good printability. Both provide higher compressive modulus than 1GG/4MC/4CNC and 1GG/4MC, and show great shear‐thinning and thixotropic behaviors. They show porous microstructure and sufficient swelling ratio to maintain high cell viability. Excellent biocompatibility of 1GG/4MC/4CNC/0.022CaCl2 and 1GG/4MC/4CNC/0.075KCl is demonstrated with cell viability of 119.55% and 100.77%, respectively, based on MTT assay. A good cell viability of 97%–98% up to 14 days was attained for both bioprinted constructs. Taken together, these novel 1GG/4MC/4CNC/0.022CaCl2 and 1GG/4MC/4CNC/0.075KCl hydrogels exhibit good attributes for a promising 3D bioprinting material.

Quality by design-based optimization of in situ ionic-sensitive gels of amoxicillin-loaded bovine serum albumin nanoparticles for enhanced local nasal delivery

A recommended first-line acute bacterial rhinosinusitis (ABR) treatment regimen includes a high dose of orally administered amoxicillin, despite its frequent systemic adverse reactions coupled with poor oral bioavailability. Therefore, to overcome these issues, nasal administration of amoxicillin might become a potential approach for treating ABR locally. The present study aimed to develop a suitable carrier system for improved local nasal delivery of amoxicillin employing the combination of albumin nanoparticles and gellan gum, an ionic-sensitive polymer, under the Quality by Design methodology framework. The application of albumin nanocarrier for local nasal antibiotic therapy means a novel approach by hindering the nasal absorption of the drug through embedding into an in situ gelling matrix, further prolonging the drug release in the nasal cavity. The developed formulations were characterized, including mucoadhesive properties, in vitro drug release and antibacterial activities. Based on the results, 0.3 % w/v gellan gum concentration was selected as the optimal in situ gelling matrix. Essentially, each formulation adequately inhibited the growth of five common nasal pathogens in ABR. In conclusion, the preparation of albumin-based nanoparticles integrated with in situ ionic-sensitive polymer provides promising ability as nanocarrier systems for delivering amoxicillin intranasally for local antibiotic therapy.

Formation mechanism of cold-set bitter apricot kernel protein isolate-gellan gum binary gels with excellent freeze-thaw stability

Binary gels with various microstructures, including apricot kernel protein isolate-gellan gum gels with high freeze-thaw stability, were obtained by combining transglutaminase covalent cross-linking and gellan gum modification. Adding 0–0.1% gellan gum (w/w) can form continuous protein network structures dominated by covalent networks and disulfide bonds. In addition to covalent cross-linking, the increase in the strength of hydrophobic and electrostatic interactions at gellan gum concentrations below 0.2% (w/w) facilitated the formation of a bicontinuous network (AGG3). When excess gellan gum was added (0.03%, w/w), gellan gelation occurred in the system, leading to the formation of heterogeneous aggregated structures (AGG4). Confocal laser microscopy revealed a dense porous structure in the continuous protein network after freeze-thaw treatment, and AGG4 showed heterogeneous and loose aggregated microstructure, while the bicontinuous network structure was maintained. The water holding capacity of AGG3 was increased by 21.36% after freezing compared with the gels without gellan gum, and AGG3 maintained high hardness and springiness. Low-field nuclear magnetic resonance and magnetic resonance imaging showed that the bicontinuous network was more conducive to the tethering ability and uniform distribution of hydrogen protons than the continuous network structure of proteins. Therefore, AGG3 exhibited excellent freeze-thaw stability.

Dacarbazine-encapsulated solid lipid nanoparticles for skin cancer: physical characterization, stability, in-vivo activity, histopathology, and immunohistochemistry.

This study examined the use of solid lipid nanoparticles (SLNs) to administer Dacarbazine (DTIC) to skin melanoma cells with minimal adverse effects. Melanoma is a tricky skin cancer to cure, and standard chemotherapy has many negative effects. Encapsulating DTIC in SLNs may allow the drug to target melanoma cells without harming healthy cells. The study developed and tested DTIC-loaded SLNs for skin melanoma treatment. This study encapsulated Dacarbazine (DTIC) in solid lipid nanoparticles (SLNs). SLNs with reversed micelles were produced utilizing specified ratios of the surfactant Kolliphor® P188 and phosphatidylcholine. To track SLN drug localisation, gold nanoparticles were conjugated to the DTIC. Nanoparticle size and form were examined using DLS and TEM. These approaches ensured SLNs had the correct size and shape for drug delivery. In the study, various parameters of the developed solid lipid nanoparticles (SLNs) were evaluated, including particle size, zeta potential, polydispersity index (PDI), entrapment efficacy, and cumulative drug permeation. The values for these parameters varied across the different formulations, with particle size ranging from 146 ± 4.71 nm to 715 ± 7.36 nm, zeta potential from -12.45 ± 2.78 mV to -30.78 ± 2.83 mV, PDI from 0.17 ± 0.013 to 0.51 ± 0.023, entrapment efficacy from 37.78 ± 2.78% to 87.45 ± 4.78%, and cumulative drug permeation from 117 ± 4.77 μg/cm2 to 275 ± 5.67 μg/cm2. To determine the optimal anti-cancer formulation, the DTIC-SLNs-8 nanoparticles were mixed with an optimized concentration of Gellan gum (0.01% w/v) and applied to DMBA-induced skin tumors in rats for six weeks, twice daily. Histopathology demonstrated that DTIC-SLNs-8-treated rats had less keratosis, inflammatory responses, and angiogenesis than free DTIC-treated rats. The development of SLNs may be a promising approach for melanoma treatment due to their improved drug retention over the skin. The optimised anti-cancer formulation DTIC-SLNs-8 showed improved efficacy with minimal side effects as compared to free DTIC.

Optimization of the Dose Rate Effect in Tetrazolium Gellan Gel Dosimeters.

Tetrazolium salts provide an appealing candidate for 3D gel dosimeters as they exhibit a low intrinsic color, no signal diffusion and excellent chemical stability. However, a previously developed commercial product (the ClearView 3D Dosimeter) based on a tetrazolium salt dispersed within a gellan gum matrix presented a noticeable dose rate effect. The goal of this study was to find out whether ClearView could be reformulated in order to minimize the dose rate effect by optimizing of the tetrazolium salt and gellan gum concentrations and by the addition a thickening agent, ionic crosslinkers, and radical scavengers. To that goal, a multifactorial design of experiments (DOE) was conducted in small-volume samples (4-mL cuvettes). It showed that the dose rate could be effectively minimized without sacrificing the integrity, chemical stability, or dose sensitivity of the dosimeter. The results from the DOE were used to prepare candidate formulations for larger-scale testing in 1-L samples to allow for fine-tuning the dosimeter formulation and conducting more detailed studies. Finally, an optimized formulation was scaled-up to a clinically relevant volume of 2.7 L and tested against a simulated arc treatment delivery with three spherical targets (diameter 3.0 cm), requiring different doses and dose rates. The results showed excellent geometric and dosimetric registration, with a gamma passing rate (at 10% minimum dose threshold) of 99.3% for dose difference and distance to agreement criteria of 3%/2 mm, compared to 95.7% in the previous formulation. This difference may be of clinical importance, as the new formulation may allow the quality assurance of complex treatment plans, relying on a variety of doses and dose rates; thus, expanding the potential practical application of the dosimeter.

Effect of different concentrations of gellan gum with/without 0.50% basil essential oil on the physicochemical properties of gellan gum-rice bran oil coating emulsions and their application in egg preservation

This work investigated the effects of different concentrations (0.10 %, 0.15 % or 0.20 %, w/v) of gellan gum (GG) with/without 0.50 % (v/v) basil essential oil (BEO) on physicochemical properties of gellan gum-rice bran oil (GG-RBO) emulsions. The results showed that GG-RBO emulsions with 0.15 % or 0.20 % GG were more stable than GG-RBO emulsion with 0.10 % GG (as evidenced by higher apparent viscosity and absolute zeta potential, but smaller average particle size and lower turbidity), thus displaying better coating performances (as evidenced by bigger contact angle but lower moisture content). The presence of BEO further improved their stability and coating performances. Coating with GG-BRO or GG-RBO-BEO emulsion with 0.15 % GG significantly delayed the increase in weight loss, and the decrease in haugh unit, yolk index and albumen pH of eggs during 42 days storage; moreover, GG-RBO-BEO emulsion caused lower total aerobic plate count. Therefore, GG-RBO, especially GG-RBO-BEO emulsion has potential in egg preservation.

Hydrogel-based encapsulation strategy for nobiletin stabilization

Controlling bioactive components' crystal growth, especially for hydrophobic functional factors, is an effective pathway for achieving their stabilization. Here, our paper proposes a method utilizing hydrogel to regulate crystal growth, using nobiletin (NOB) as a model. Results showed that the NOB crystallization was controlled by gellan gum (GG) concentrations and the ratios of GG to NaCl. Notably, 1% of GG-based hydrogel with 0.5% NaCl efficiently inhibited the crystals' growth. X-ray diffraction results confirmed that GG could regulate the crystallinity of NOB. Fourier transform infrared spectroscopy analysis verified the presence of hydrogen bond interaction between GG and NOB. Besides, the texture and rheological properties of GG-NOB composite gels were also investigated in detail. More importantly, the final composite gels exhibited sustained release properties and significantly improved release efficiency compared to the pure NOB sample. In summary, our study proposed a straightforward stabilization strategy for hydrophobic substances, attempting to overcome some of the barriers in food processing and storage.

Peanut protein-polysaccharide hydrogels based on semi-interpenetrating networks used for 3D/4D printing

The rise of 3D printing technology has made the personalization of food possible. In this study, peanut protein-polysaccharide semi-interpenetrating networks were constructed to improve the gelling and printing properties of composite hydrogels. The rheological and mechanical test results showed that the storage modulus and fracture stress of peanut protein composite hydrogels increased with increasing carrageenan and gellan gum concentrations. The storage modulus (G′) and hardness of the composite hydrogels with 1.5% polysaccharide addition reached above 104 Pa and 700 g, respectively. The thermal reversibility of both carrageenan and gellan gum gels meant that composite hydrogels could be created as recyclable printable edible inks for 3D food printing. In addition, the composite hydrogels were designed to change color in response to alterations in pH, which meant they could be used in 4D food printing applications, i.e., in situations where the ink changes its attributes sometime after printing. The results of this study should facilitate the rational design and fabrication of plant-based edible inks that can be used for the development of personalized foods with unique properties.