Guar gum (GG) as a polymer biopolymer is widely used in the field of bio-based packaging. However, its poor mechanical properties, barrier properties and high viscosity greatly hinder its use as an ...effective packaging material. Therefore, this study introduced CPTES to improve the mechanical (16.58–27.39 MPa) and tensile properties (26.80 %–30.67 %). The FTIR and XRD results indicated a strong interaction between the biofilm fractions modified by CPTES, CPTES bound to the hydroxyl groups on GG and formed a dense polysiloxane network through adsorption and grafting. OM and AFM reflect a denser and flatter film structure on the surface of the G30 film, which has the best film formation. Based on this, the pH of the solution was further adjusted to reach an alkaline environment, disrupting the intermolecular binding through electrostatic repulsion. The rheological behavior indicates that the viscosity and viscoelasticity of film solution gradually decrease with the increase in pH. OM and AFM results show that the G30/8 film has the best compact properties, while the nonporous compact film structure further improves the mechanical, barrierand and thermodynamic properties of the film. Accordingly, the findings of this study had a certain value for regulating the low viscoelasticity of GG emulsion and enhancing the stability of film formation.
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•(3-Chloropropyl) triethoxysilane improved mechanical and barrier properties of film.•The polysiloxane structure enhanced the connectivity between molecular chains.•The pH regulated the solution viscoelasticity.•Compared with guar gum, G30/8 displayed the best fluid and film performance.
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•Functionalized guar gum with tuned physicochemical properties for controlled drug delivery applications.•Guar gum based micro-formulations includes emulsion cross linking and ionic ...gelation method.•Cross-linking of guar gum creates an interpenetrating polymer networks with mechanical and thermal properties.•Most widely used approach for nano-formulation is the single/double step emulsion method.
Guar gum a non-ionic polysaccharide obtained from the seeds of Cyamopsis tetragonolobus of the Leguminosae family is found abundantly in nature. It finds extensive use in a variety of fields such as food industry, textile industry, paper industry, cosmetic industry, pharmaceutical industry among many others. Guar gum being a natural polymer with several interesting properties like biodegradability, biosafety, biocompatibility and sustainability presents a potential case for use in pharmaceutical formulations and drug release studies. Although guar gum in its native form finds limited use as delivery carriers owing to its high swelling characteristics in aqueous medium, this property can be significantly altered through derivatization of functional groups, cross-linking and grafting for application in a wide spectrum of biomedical fields. This review article provides a comprehensive overview of different modifications made on guar gum through derivatization in the quest to make them more versatile for drug delivery applications. The drug entrapment efficacy and in vitro drug release from different micro- and nano-formulations using guar gum for controlled release are also assessed.
Binders have been reported to play a key role in improving the cycle performance of Si anode materials of lithium‐ion batteries. In this study, the biopolymer guar gum (GG) is applied as the binder ...for a silicon nanoparticle (SiNP) anode of a lithium‐ion battery for the first time. Due to the large number of polar hydroxyl groups in the GG molecule, a robust interaction between the GG binder and the SiNPs is achieved, resulting in a stable Si anode during cycling. More specifically, the GG binder can effectively transfer lithium ions to the Si surface, similarly to polyethylene oxide solid electrolytes. When GG is used as a binder, the SiNP anode can deliver an initial discharge capacity as high as 3364 mAh g−1, with a Coulombic efficiency of 88.3% at the current density of 2100 mA g−1, and maintain a capacity of 1561 mAh g−1 after 300 cycles. The study shows that the electrochemical performance of the SiNP anode with GG binder is significantly improved compared to that of a SiNP anode with a sodium alginate binder, and it demonstrates that GG is a promising binder for Si anodes of lithium‐ion batteries.
Guar gum is used as a robust binder for a silicon nanoparticle anode of a lithium‐ion battery for the first time. With a large number of polar hydroxyl groups, the guar gum binder can provide effective transport pathways for lithium ions, which significantly improves the electrochemical performance.
In this work, an environmental friendly dust suppressant with improved wettability and coagulation properties was developed by a chemical modification method. The hydroxypropyl guar gum was ...synthesized by nucleophilic substitution reaction between natural polymer guar gum and propylene oxide. Through a series of optimization of adjuvant agents and viscosity experiments, the optimum formulation contained moisture agent W + 0.8% hydroxypropyl guar gum. A mastersizer 3000 laser particle size analyzer was used to determine that the wettability of coal dust increases with the increase of particle size. The dust suppression agent and coal dust were fully mixed and bonded together, as observed by a high-resolution scanning electron microscopy. The spray dust reduction experiment results show that the spray dust reducer developed in this paper can significantly reduce the dust concentration, and the average dust removal rates of total dust and respirable dust are increased to 83.94% and 84.08%, respectively.
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•Chemical dust reduction is especially suitable for hydrophobic respirable dust.•The optimum composite spraying dust suppression agent concentration is determined.•Wrinkles were found on the surface of granules of modified GG.•The dust-reducing performance was significantly higher than that of clear water.
Processing of concentrated lignocellulosic biomass suspensions typically involves the conversion of the cellulose into sugars and sugars into ethanol. Biomass is usually pretreated via methods like ...comminution or steam explosion to form fine cellulosic fibers to be dispersed into an aqueous phase for further treatment. The resulting cellulose suspensions need to be pressurized and pumped into and out of various processing vessels without allowing the development of flow instabilities that are typically associated with “demixing”, that is, the segregation of the cellulosic biomass from the aqueous phase via the formation of mats of cellulosic fibers and the filtration of the aqueous phase. Such demixing can prevent continuous processing at high rates. Here, the development of flow instabilities via the demixing effect for cellulose suspensions is demonstrated using capillary and compressive squeeze flows. It is shown that the use of a gelation agent, hydroxypropyl guar gum, at the critical concentration of 0.5 wt% or higher significantly affects the viscoelastic material functions of cellulosic suspensions, improves the dispersive mixing of the fibers within the aqueous phase, and results in the elimination of the flow instabilities and associated demixing effects that are ubiquitously observed during the pressurization and processing of cellulosic suspensions.
•Edible films were produced using different pea starch, guar gum and glycerol concentrations by casting method.•The Box–Behnken response surface design (BBD) was an effective tool in evaluating the ...physical and optical properties of biocomposite edible films.•The proportion of the two polysaccharides in the film influenced the physical and optical properties of the films to different extents.•Food and non-food applications of pea starch films were improved with incorporation of guar gum and glycerol.
The influence of process variables (pea starch, guar gum and glycerol) on the viscosity (V), solubility (SOL), moisture content (MC), transparency (TR), Hunter parameters (L, a, and b), total color difference (ΔE), yellowness index (YI), and whiteness index (WI) of the pea starch based edible films was studied using three factors with three level Box–Behnken response surface design. The individual linear effect of pea starch, guar and glycerol was significant (p<0.05) on all the responses. However, a value was only significantly (p<0.05) affected by pea starch and guar gum in a positive and negative linear term, respectively. The effect of interaction of starch×glycerol was also significant (p<0.05) on TR of edible films. Interaction between independent variables starch×guar gum had a significant impact on the b and YI values. The quadratic regression coefficient of pea starch showed a significant effect (p<0.05) on V, MC, L, b, ΔE, YI, and WI; glycerol level on ΔE and WI; and guar gum on ΔE and SOL value. The results were analyzed by Pareto analysis of variance (ANOVA) and the second order polynomial models were developed from the experimental design with reliable and satisfactory fit with the corresponding experimental data and high coefficient of determination (R2) values (>0.93). Three-dimensional response surface plots were established to investigate the relationship between process variables and the responses. The optimized conditions with the goal of maximizing TR and minimizing SOL, YI and MC were 2.5g pea starch, 25% glycerol and 0.3g guar gum. Results revealed that pea starch/guar gum edible films with appropriate physical and optical characteristics can be effectively produced and successfully applied in the food packaging industry.
•In view of the tremendous potential of guar gum in carrier based formulation technology, a novel series of porous hydrogels prepared aimed at generating functional group enriched network of grafted ...polyacrylate onto the polysaccharide chains.•Comprehensive standardization of reaction parameters and characterization has been presented.•This unique class of biopolymeric porous hydrogels possess tremendous potential as carriers of inputs such as pesticides, microbes, nutrients etc. Present study demonstrates utility of prepared materials as effective carriers of biocontrol microbes with enhanced shelf life and bio efficacy properties.•Till date to the best of information, guargum based superabsorbent hydrogels have been reported but no work has been reported on guargum based porous or superporoushydrogels.
A new series of eco-friendly cross linked guar gum-g-poly(acrylate) porous superabsorbent hydrogels was prepared by in situ grafting polymerization and cross-linking on to a natural guar gum employing N,N-methylene bis acrylamide as cross linker. Morphological and structural characterization of the prepared hydrogels (SPHs) done by Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and solid state C13 NMR spectroscopy confirmed formation of porous grafted and crosslinked hydrogel structure. Increase in cross linker concentration in the feed mass exhibited decrease in porosity and increase in density of the hydrogels. Swelling of an optimized hydrogel (SPH) in response to external stimuli namely, salt solutions, fertilizer solutions, temperature, and pH exhibited high swelling ratios in various environments. Swelling rate of the SPH was faster than the corresponding nonporous superabsorbent hydrogel. The prepared hydrogels can serve as excellent carriers of pesticides, fertilizers and agriculturally important microbes. Biocontrol formulations based on a representative SPH exhibited excellent shelf-life characteristics and bioefficacy against phytopathogenic fungus Pythium aphanidermatum.
The present study was carried out to maintain the quality of sweet cherry by using the guar gum (GG) and ginseng extract (GSE) coatings during storage at 20 °C and 70–75% RH for 8 days. Coatings with ...0.15% (m/v) GG + 0.1% (m/v) calcium chloride + 0.1% (m/v) glycerol + 1% (m/v) GSE presented the best characteristics to uniformly coat sweet cherry surface. Quality (weight loss, decay percentage, firmness), respiration rate, nutrient components (total soluble solids, titratable acid, ascorbic acid, total phenols, anthocyanins) and malondialdehyde evaluations were performed. Coatings with GG-GSE controlled water loss and delayed loss of firmness and of titratable acid, ascorbic acid and total phenols, compared with untreated fruit. Overall, coatings developed in this study extend sweet cherries’ shelf life for about 8 days, demonstrating for the first time that the combination of guar gum and ginseng extract as edible coating materials has great potential in expanding the shelf life of fruits.
•Guar gum and ginseng extract coatings were developed to maintain the quality of sweet cherry.•Coatings with ginseng extract showed a significant delays in malondialdehyde of sweet cherry.•Coatings with ginseng extract were effective to improve the quality and nutrients of sweet cherry.
The dietary fiber guar gum has beneficial effects on obesity, hyperglycemia and hypercholesterolemia in both humans and rodents. The major products of colonic fermentation of dietary fiber, the ...short-chain fatty acids (SCFAs), have been suggested to play an important role. Recently, we showed that SCFAs protect against the metabolic syndrome via a signaling cascade that involves peroxisome proliferator-activated receptor (PPAR) gamma repression and AMP-activated protein kinase (AMPK) activation. In this study we investigated the molecular mechanism via which the dietary fiber guar gum protects against the metabolic syndrome. C57Bl/6J mice were fed a high-fat diet supplemented with 0% or 10% of the fiber guar gum for 12 weeks and effects on lipid and glucose metabolism were studied. We demonstrate that, like SCFAs, also guar gum protects against high-fat diet-induced metabolic abnormalities by PPARgamma repression, subsequently increasing mitochondrial uncoupling protein 2 expression and AMP/ATP ratio, leading to the activation of AMPK and culminating in enhanced oxidative metabolism in both liver and adipose tissue. Moreover, guar gum markedly increased peripheral glucose clearance, possibly mediated by the SCFA-induced colonic hormone glucagon-like peptide-1. Overall, this study provides novel molecular insights into the beneficial effects of guar gum on the metabolic syndrome and strengthens the potential role of guar gum as a dietary-fiber intervention.
Coalbed methane (CBM) presents a promising energy source for addressing global energy shortages. Nonetheless, challenges such as low gas production from individual wells and difficulties in breaking ...gels at low temperatures during extraction hinder its efficient utilization. Addressing this, we explored native microorganisms within coal seams to degrade guar gum, thereby enhancing CBM production. However, the underlying mechanisms of biogenic methane production by synergistic biodegradation of lignite and guar gum remain unclear. Research results showed that the combined effect of lignite and guar gum enhanced the production, yield rate and concentration of biomethane. When the added guar gum content was 0.8 % (w/w), methane production of lignite and guar gum reached its maximum at 561.9 mL, which was 11.8 times that of single lignite (47.3 mL). Additionally, guar gum addition provided aromatic and tryptophan proteins and promoted the effective utilization of CC/CH and OCO groups on the coal surface. Moreover, the cooperation of lignite and guar gum accelerated the transformation of volatile fatty acids into methane and mitigated volatile fatty acid inhibition. Dominant bacteria such as Sphaerochaeta, Macellibacteroides and Petrimonas improved the efficiency of hydrolysis and acidification. Electroactive microorganisms such as Sphaerochaeta and Methanobacterium have been selectively enriched, enabling the establishment of direct interspecies electron transfer pathways. This study offers valuable insights for increasing the production of biogenic CBM and advancing the engineering application of microbial degradation of guar gum fracturing fluid. Future research will focus on exploring the methanogenic capabilities of lignite and guar gum in in-situ environments, as well as elucidating the specific metabolic pathways involved in their co-degradation.
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•The synergistic effect of lignite and guar gum can improve the anaerobic digestion performance.•The methanogenesis of single guar gum was inhibited.•Lignite can accelerate the conversion of volatile fatty acids to methane and prevents acid inhibition.•The addition of guar gum improves the biodegradation of coal.•A novel mechanism was developed that lignite can promote direct interspecies electron transfer (DIET).
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