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This study analyses the effectiveness of the biopolymer xanthan gum (XG) to improve the mechanical properties of silty sand. The study focuses on the effects of the curing time and the content of XG on the unconfined and confined behaviour of soil treated with this biopolymer. The study was carried out with specimens cured under high-humidity conditions, through the comparison of the unconfined compressive strength (UCS), stiffness, compressibility and vertical yield stress of non-stabilised and biostabilised specimens, obtained from UCS and oedometer tests. Additionally, the pH value and results of scanning electron microscopy (SEM)/ energy-dispersive X-ray analysis (EDX) tests are presented and discussed. The biostabilisation of this soil with XG induces a more ductile stress–strain behaviour, a moderate increase in UCS and stiffness, and in the increase of the one-dimensional compressibility, with a greater effect for higher XG contents. The SEM/EDX tests show that the biopolymer induces a random biopolymer network in the biostabilised specimens that is related to the strengthening obtained.

Carboxymethyl cellulose (CMC) has emerged in oil and gas industries as a superior substitution to the conventional HPAM and xanthan gum (XG) for high viscosity polymer flooding application. In this study, the combined effect of conventional surfactant, sodium dodecylbenzenesulfonate (SDBS) and CMC for potential surfactant-polymer (SP) flooding in enhanced oil recovery (EOR) has been investigated. Thereafter, SDBS – CMC interaction and the functional groups present in CMC were appropriately identified. The presence of various C–O bonds signifies the existence of carboxymethyl group which greatly influence the rheological properties of CMC solution. The behaviour of SDBS–CMC was characterized by their viscosity, shear rate, solubilization, wettability, and surface tension. Tertiary flooding utilizing SDBS-CMC was performed and compared to commercial SDBS-XG SP flooding. The results indicate several SDBS-CMC combinations are favourable for EOR application. Solution viscosity shows direct relationship with CMC concentrations. Consequently, at any given SDBS concentrations, significant increment was observed at 0.3 wt% and above. However, the trend displayed inconclusive relation to SDBS fractions. Majority of the SDBS-CMC combinations generate Winsor III emulsions particularly at CMC of 0.2 and 0.3 wt%, while Type II were observed in few combinations. Increasing CMC concentrations increased the contact angle, while gradual reductions were observed with SDBS concentrations. The gradual reduction in surface tension was highly influenced by the addition of CMC rather than SDBS. A novel combination of 0.3 wt% SDBS and 0.4 wt% CMC possessed an encouraging criterion in term of viscosity, solubilization, and surface tension reduction for EOR application. Flooding experiment from several SDBS-CMC combinations proved to recover additional oil ranging 16.4–20.2% of oil initially in place (OIIP). The trend in incremental oil recovery is similar to that of when utilising SDBS-XG.

The phytochemical-rich extract obtained from black jamun pulp were encapsulated using vibrating dripping extrusion technique. The utilisation of alginate (AL) with four variations of core-shell material comprising gum Arabic (AL-GA), guar gum (AL-GG), pectin (AL-P) and xanthan gum (AL-X) was engaged to form calcium-alginate based lyophilised jamun extract encapsulated beads. It resulted that among four variations, lyophilised alginate with AL-GG based encapsulated jamun extract filled beads have better physicochemical characteristics and 95% encapsulation efficiency. The results revealed the morphological comparison of each variation. The release behaviour of AL-GG based beads has a higher release of total phenolics (TPC) and total anthocyanin content (TAC). The release kinetics model involving Ritger-Peppas and Higuchi model were applied for release TPC and TAC of all variations of beads. The Ritger-Peppas model was found best suitable in terms of average R2 (0.965) and lowest χ2 (0.0039). The release kinetics study showed that AL-GA based beads followed by AL-GG could also be the best suitable in release behaviour using simulated gastrointestinal fluids at 140–160 min. Overall, results shown the encapsulated Jamun beads have the best agro-industrial efficacy in form of phytochemical compounds based microparticles, holding decent antioxidant potential.

A one-step double emulsification protocol using sodium caseinate (SC) and xanthan gum (XG) mixture was developed for water-in-oil-in-water (W/O/W) double emulsions. Effect of pH on the stability of these emulsions has also been studied. The study of stability of emulsions was conducted over a period of 20 days. This monitoring was revealed by studying of the physicochemical and rheological properties and bay an optical microscopy observations of emulsions after formulation. The apparent viscosity of the emulsions obtained strongly depends on the pH of the external aqueous phase. The optimum pH for stabilizing W / O / W emulsions by SC/XG using direct process is 5 or 5.5.

To investigate the effect of surfactants in compound solution on the wetting-agglomeration properties of the bituminous coal dust, this paper selected anionic surfactants SDS, SDBS and non-ionic surfactants APG0810 and PPG400 for compounding with agglomerated solutions 0.05 wt% XTG (xanthan gum). The sink test, surface tension test, viscosity test, fourier transform infrared spectroscopy(FTIR) and scanning electron microscope(SEM) were used to investigate the wettability and agglomeration of the four compound solutions and analyze the agglomeration wetting mechanism. The results show that SDBS has the most obvious improvement in the wettability of compound solution. The surface tension of SDBS + 0.05 wt% XTG is 28.98 mN/m after CMC value and sinking rate will reach 14.29 mg/s with 0.6 wt% SDBS in compound solution; Furthermore, FTIR results showed that surface hydroxyl content of bituminous coal dust treated by 0.2 wt% SDBS + 0.05 wt% XTG solutions has increased 26.3% than that treated by 0.05 wt% XTG, which promoted the adsorption of xanthan gum molecules on the coal surface. The presence of surfactants decreases the viscosity and surface tension of compound solution, and xanthan gum–surfactants interaction will promote bituminous coal dust agglomeration effect. This agglomeration mechanism is mainly reflected in the distribution mechanism and bituminous coal dust can form to large agglomerates under this action.

The accurate prediction of wellbore thermal profile is essential to ensure the success of any drilling operation. Currently, the heat capacity values used for predicting the thermal behavior of oil and gas wells assume the heat capacity of the drilling which leads to errors. Thus, determining the heat capacities of drilling mud systems would aid to efficiently predict the thermal distribution of wells. In this study, the heat capacities of fresh and aged mud samples of 0.8 wt% xanthan gum water-based mud and 0.8 wt% polyanionic cellulose (PAC) water-based mud and their blend system (0.4 wt% xanthan gum + 0.4 wt% PAC) were measured using a differential scanning calorimetry (DSC) from 5 to 100 °C. The new and aged samples represent testing the mud as fresh samples and over time (1–3 days). The result shows that the specific heat capacity values of the drilling muds differ from the heat capacity of water (which is generally used for drilling-related heat transfer modeling and simulations). High heat capacity values were observed for the 0.8 wt% xanthan gum mud system compared with the 0.8 wt% PAC mud system. However, the blend of 0.4 wt% xanthan gum + 0.4 wt% PAC exhibited the highest heat capacity values. In both fresh and aged samples, the heat capacity of 0.8 wt% xanthan gum mud was in the range of 3.805–4.287 J/g.oC. While 0.8 wt% PAC mud and 0.4 wt% xanthan gum + 0.4 wt% PAC mud system were within 0.7635–1.1329 J/g.oC, and 4.134–4.324 J/g.oC, respectively. These experimental heat capacity values are recommended for accurate oil & gas well heat transfer behavior modeling and simulation predictions and related studies.

© 2022, The Author(s), under exclusive licence to American Association of Pharmaceutical Scientists.Buccal film formulations, including antifungal nystatin, anti-inflammatory agent hydrocortisone acetate, and local anesthetic lidocaine hydrochloride for pain relief, were developed. Bioadhesive films were fabricated with hydrophilic polymers, hydroxyethyl cellulose (HEC), and xanthan gum (XG) and dried in the incubator. Textural, swelling, and bioadhesive properties, physicochemical and in vitro release characteristics, and antifungal activities of bioadhesive films were evaluated. Bioadhesive films significantly extended nystatin release by prolonging retention time of the target area formulation while rapidly releasing hydrocortisone acetate and lidocaine HCl, reducing drug administration. The polymer type affected bioadhesion strength and erosion ratio, and XG formulations had more polymer suitability. Consequently, XT-O2 formulation that was prepared with xanthan gum and tween 80, was best for its highest antifungal film activity (20.00 ± 0.07 mm), released nystatin (44.296% ± 1.695), and lowest erosion matrix (36.719% ± 0.249). The selected formulation can be used for compatibility, stability and in vivo studies targeted oral candidiasis infections. Graphical Abstract: [Figure not available: see fulltext.]

Low-sugar and high-protein adhesives have broad market application prospects, while natural plant proteins have confronted technical bottlenecks due to their poor adhesion. In this study, the effects of ethanol with different concentrations (0–80%) on the adhesion properties of walnut protein isolate-xanthan gum (WNPI-XG) composite adhesives were investigated. Results showed the bonding strength of WNPI-XG treated with 40% ethanol reached 12.55 MPa, the denaturation temperature and the surface hydrophobicity increased to 87.91 and 185.07 respectively, displaying the best rheological and texture properties. It also indicated appropriate concentration of ethanol (40%) didn't change the molecular weight of WNPI-XG, but greatly strengthened the fluorescence intensity, leading changes in contents of reactive sulfhydryl groups, electrostatic forces, hydrophobic interactions, hydrogen bonds and disulfide bonds. Furthermore, the treatment also facilitated a conformation conversion of the secondary structures from β-sheet to α-helix, promoting the full unfolding of protein molecules. The microstructure analysis showed after 40% ethanol treatment, the WNPI structure was uniform, the surface of WNPI-XG adhesive was flat and smooth, combined more closely with water molecules. By analyzing the influence of ethanol treatment on adhesion of WNPI-XG, the research laid a theoretical foundation for protein modification, providing good technical references for its development and utilization.

Yak yogurt, one of the naturally fermented dairy products prepared by local herdsmen in the Qinghai-Tibet Plateau, contains a diverse array of microorganisms. We isolated and identified a novel Streptococcus thermophilus strain, ZJUIDS-2-01, from the traditional yak yogurt. We further purified and carried out detailed structural, physiochemical, and bioactivity studies of an exopolysaccharide (EPS-3A) produced by S. thermophilus ZJUIDS-2-01. The weight-average molecular weight (Mw) of EPS-3A was estimated to be 1.38 × 106 Da by High-Performance Gel Permeation Chromatography (HPGPC). The monosaccharide analysis established its composition to be glucose, galactose, N-acetyl-D-galactosamine, and rhamnose in a ratio of 5.2:2.5:6.4:1.0. The molecular structure of EPS-3A was determined by the combination of permethylation analysis, FT-IR, and NMR spectroscopic techniques. The ζ-potential measurements indicated that EPS-3A had a pKa value of ~4.40. The DSC yielded a melting point (Tm) of 80.4 °C and enthalpy change (ΔH) of 578 J/g for EPS-3A, comparable to those of the xanthan gum (XG), a commercial EPS. EPS-3A exhibited better O/W emulsion stability and flocculating capacity than XG. Furthermore, it also demonstrated similar antioxidant activity to XG and promising in vitro antibacterial properties. This work evidenced that EPS-3A derived from S. thermophilus ZJUIDS-2-01 holds the potential for food and industrial applications.

Jaggery is a product that is widely consumed, particularly by the rural people, and is manufactured from sugarcane juice. Jaggery and confectionery are traditional cane based sweets consumed by a large number of people worldwide. Traditionally, jaggery was made by boiling sugarcane juice in an open pan, which consumes a lot of energy and time. The term "hard candy" encompasses a diverse variety of confectionery. Its usage is ambiguous and imprecise, with no clarity on its nature and uses. The hard candy sugar glasses are referred to as "high-boiled" sweets due to their hard-crack nature. To facilitate the preparation of hard-boiled jaggery based confectioneries, sensory and chemical studies were performed on a variety of gelling agents/thickening agents. Candy that has been boiled to a high temperature has a perceptible firmness without sticky nature. Hard boiled sugar candy has a noticeable hardness without being sticky. However, when sugar is replaced with jaggery, the resulting candy has an undesirable chewy texture and stickiness. In this work, jaggery was blended with hydrocolloid/gelling agents such as gum acacia, xanthan gum, guar gum, and gelatin to improve the quality and sensory properties of hard-boiled candy. While the mean sensory ratings were all favorable, the taste scores differed significantly across the variants. As a result of this research, hard-boiled candy prepared using jaggery and gelatin combination was found to be preferred, indicating that viable goods could be manufactured.

Electrolyzed waters, containing mainly hypochlorous acid, are used in dental practice because of their high microbicidal effect. For wider use, three neutral electrolyzed water-based gels, namely, HOCl-containing aqueous gels were prepared with a thickening/gelling agent in this study. We evaluated their microbicidal effects against four strains and storage stabilities indicated by available chlorine concentration. Immediately after preparation, all gels (70 ppm) could completely remove microbes by a 3-min treatment. The gel prepared with xanthan gum remarkably reduced its available chlorine concentration even under shaded and refrigerated storage conditions, failing to maintain its microbicidal effect following 1-day storage, whereas other gels, prepared with carboxyvinyl polymer or agar, maintained effective concentration (>20 ppm), with high microbicidal effects following 9-day and 21-day storage, respectively. Neutral electrolyzed water-based gels might be useful to remove oral microbes. Based on our results, agar is the most suitable thickening/gelling agent from the viewpoint of storage stability.

Objective The effectiveness of using food-grade coolant thickener solutions on the amount of aerosols generated and splatter contamination spread distance during simulated ultrasonic scaling was examined. Materials and methods The study was performed using a phantom lower jaw placed on a black box. Simulated ultrasonic scaling was performed for 2 min using four coolant solutions: distilled water (control), 2% wt. polyacrylic acid (PAA), 0.4% wt. xanthan gum (XA), and 0.4% wt. carboxymethyl cellulose (CMC). The simulation was repeated 10 times for each coolant group. The generated aerosols and droplets were quantified using a handheld particle counter, and the splatter contamination spread distance was evaluated by adding tracing fluorescent dye to the coolant reservoir supplying the scaler unit. One-way multivariate analysis of variance was performed to determine the difference among coolant groups (a = .05). Results The amount of aerosols and droplets and splatter contamination distance (p .05). Conclusion The food-grade coolant thickeners could reduce the amount of generated aerosols and splatter contamination distance but not completely eliminate them. PAA and CMC solutions were more effective in reducing the aerosol/splatter during scaling compared to XA. Clinical relevance Many dental procedures generate aerosols and splatter, which pose a potential risk to the patients and dental personnel, especially during the current COVID-19 pandemic.

Seedling transplanting is widely used in rice cultivation. Systemic insecticides can be delivered to seedling roots by application through rice seedling boxes before transplanting. The most challenging aspect is to provide long-term control of rice pests and overcome transplanting shock. Precise control of the release rate of insecticide can meet these requirements. Pymetrozine is a promising insecticide used for the control of rice planthoppers resistant to neonicotinoid insecticides.In this study, four controlled-release granular formulations of pymetrozine were prepared based on a mixture of cost-effective and biodegradable kaolin and xanthan gum or a mixture of calcined kaolin and xanthan gum. Fluorescence images showed that different 3D networks were formed in the four granular formulations. The four granular formulations showed different water uptake rates and release rates of pymetrozine in water. Pymetrozine release rate was positively correlated with the water uptake capacity, rather than the water uptake rate of granules. Diffusion was the dominant mechanism for the release of pymetrozine from granules. Pymetrozine was found to reduce the survival of transplanted rice seedlings suffering from transplanting shock. Incorporating pymetrozine in controlled-release granules alleviated this phytotoxicity. The survival rate of rice seedlings in granular pymetrozine treatments ranged 68.8-85.0%, whereas the survival rate was50% for powdered pymetrozine treatments. Additionally, four prepared granule formulations had a significant control effect on rice planthopper with efficacies ranging from 76.7% to 98.0% 40 days after seedling box treatment.The granule with an intermediate release rate of pymetrozine was shown to be more suitable for seedling box treatment than field application and traditional liquid spraying for the long-term control of paddy planthoppers. © 2021 Society of Chemical Industry.

Gum arabic (GA) capacity as an enhanced oil recovery (EOR) agent is studied and compared to the commonly applied xanthan gum (XG). FTIR and TGA characterisation of these two polyelectrolytes and a rheology study by viscosity measurement was conducted on their polymeric and nano-polymeric solution at varying concentrations of the polymers and nanoparticles (NP). Coreflooding experiments were conducted based on a sequence of waterflooding and three slugs of increasing concentration of polymeric (and nano-polymeric) solutions to evaluate EOR performance. Results show similar rheology and oil recovery for 1.0 wt% GA and a 0.1 wt% XG polymeric solution. And the viscosity of GA tends to be Newtonian at a relatively high shear rate. The magnitude of incremental oil recovery of the first slug is independent of the GA concentration but significant for XG. However, the impact of nano-polymeric solution on oil recovery is higher than the polymeric solution. The increase in NP concentration played a vital role in oil recovery, thereby connoting the significance of IFT, contact angle, and its associated mechanisms for EOR. And FTIR affirms that the hydroxyl group in XG is less than GA, thus responsible for adsorption of GA compared to XG.

Recently, removal of synthetic dyes, especially cationic dye of malachite green (MG), and inhibition of the growth of pathogenic microorganism from drinking water have gained much interest due to their high toxic potency for aquatic biosystems. Herein, a new dye adsorbent with outstanding antibacterial activity was fabricated based on xanthan gum (XG) and SiO2 nanoparticles through ultrasonication followed by the crosslinking polymerization with vinyl imidazole monomer. The nano adsorbents were characterized with various techniques such as FTIR, XRD, SEM, EDX, and TEM. The nanocomposites were applied as a filter for discarding MG dye and killing the growth of bacterial strains such as E.coli and S.aureus which are considered as the common impurities for drinking water. The data revealed that a maximum adsorption capacity was recorded as 99.5% (Qmax = 588.2 mg/g) at optimum conditions including 10 mg nanocomposite, 10 mL of MG dye (450 ppm), pH = 7, the temperature of 30 °C, and the adsorption time was adjusted within 6 h. The process of dye adsorption was applied to the common isotherm models of Langmuir, Temkin, and Freundlich, and the findings showed that the adsorption behavior was well fitted with the Langmuir one (R2 = 0.9983). Moreover, different adsorption kinetic models such as pseudo-first order, pseudo-second order, and intra-particle diffusion were studied for understanding the mechanism of MG adsorption onto nanocomposite surface. It was found that both intraparticle diffusion and pseudo-first-order have participated evenly in the adsorption mechanism of MG dye. Ultimately, the as-prepared nanocomposites were tested against the growth of S. aureus, and E.coli manifesting a superior inhibition diameter as 23.5 ± 0.50, and 25.33 ± 0.47 mm against E.coli, and S. aureus, respectively. Therefore, our new XG-g-PVI/SiO2 adsorbent is a very promising adsorbent for the fast and efficient capture of dyes from aqueous solutions.

The development of plant-based milks for use as functional foods is relatively new and challenging. The objective of this work was to develop and characterize two coconut milk products fermented by Lactobacillus reuteri LR 92. The best proportion of gums to promote greater viscosity and absence of syneresis of the beverage was 0.15% xanthan gum (w/v) and 0.05% guar gum (w/v). Two products were formulated: fermented coconut milk (FC) and fermented coconut milk with strawberry pulp (FCS). After gastrointestinal simulation, a high survival rate of L. reuteri was found for the products, with 81.63 ± 0.58% for FC and 74.17 ± 1.65% for FCS. In the hedonic acceptance sensory test (total 9 points), the products obtained global scores above 7.5. In the attitude scale test (total 7 points), 5.10 ± 1.28 for FC and 5.48 ± 1.30 for FCS. Among the fatty acids detected, the products had a higher percentage of lauric acid, with values ranging from 37.89 ± 0.89% to 44.45 ± 3.16%. The FC and FCS products showed promising results, indicating that fermented coconut milk beverages are suitable for the development of new functional products with high acceptability by the consumer. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13197-021-05303-1.

Recently, nanoparticle additives have been used to improve stability and hence efficiency of chemicals during enhanced oil recovery. Herein, a comparative analysis of the application of nanoparticle-stabilized xanthan gum for oil recovery applications was investigated. The nanoparticles used as additives are silicon oxide (SiO2), metallic aluminium oxide (Al2O3), and titanium oxide (TiO2). Rheological measurements were carried out to examine the shear viscosity of the polymeric nanofluids under a range of salinity typical of reservoir conditions. Interfacial tension (IFT) experiment was conducted using Kruss tensiometer. Oil displacement studies were carried out to examine the incremental recovery factor of the polymeric nanofluids. The polymeric nanofluids exhibited better rheological behaviour compared to bare xanthan gum (XG) polymer. At 0.5 wt.% nanoparticle concentration, 0.5 wt.% polymer concentration, shearing rate of 10 s−1, and 3 wt.% NaCl concentration, rheology result shows that the shear viscosity of SiO2-XG, Al2O3-XG, and TiO2-XG is 423 mPa.s, 299 mPa.s, and 293 mPa.s, respectively. Moreover, the polymeric nanofluids lowered the IFT of the oil/brine interface due to adsorption at the nanoparticles at the interface. Finally, oil displacement result confirms that the incremental oil recovery after water flooding by Al2O3-XG, TiO2-XG, and SiO2-XG is 28.4%, 27.6%, and 25.2%, respectively.

Bentonite clay is most commonly used as a landfill liner but is resource-intensive and suffers drawbacks like large volume change and desiccation cracking. It also poses construction difficulties and the handling of a large volume of material. In situ soil can be successfully modified into base liners for landfills which offers an economical and sustainable alternative to bentonite liners. In this study, an exocellular biopolymer, xanthan gum, is used to improve the in situ soil and provides a novel alternative liner material. A comparative study is also made by modifying the in situ soil with various percentage of bentonite. The results show that the maximum dry density of the in situ soil increased marginally for both the additives. Hydraulic conductivity decreased from 2.87 × 10–3 to 4.46 × 10–8 cm/s at 1% xanthan gum addition while in case of bentonite it reduces to 4.81 × 10–8 cm/s at 30% addition. This significant reduction in hydraulic conductivity on stabilizing soil with xanthan gum is attributed to gel coating on the soil surface and gel plug formation in the soil matrix, confirmed by morphological studies. Choice of xanthan gum for stabilizing soil and modifying it into baseliners is economical than bentonite clay. The mechanism of bio-plugging in xanthan gum stabilized soil will also control leachate movement through the soil. Hence, xanthan gum, a renewable, sustainable and carbon negative biopolymer, can be successfully used to modify in situ soil into clay liner.

Thermal burns are a major cause of death and suffering around the globe. They can cause debilitating, life-altering injuries as well as lead to significant psychological and financial consequences. Several research works have been conducted in attempt to find a wound healing therapy that is successful. At present, hydrogels have been widely used in cutting-edge research for this purpose because they have suitable properties. This study aimed to see how therapy with chitosan-polyethylene glycol (Ch-Peg) based hydrogels affected the healing of burn wounds in rats. With the concern of public health, xanthan gum (X), boric acid (B), gelatin (Ge), polyethylene glycol (Peg), chitosan (Ch), glutaraldehyde (G), and HPLC-grade water were prepared using X : Ge : G, X : Ge : Peg : G, X : Ge : Ch : G, X : Ge : Peg : Ch : G, X : Ge : B : Ch : G, X : Ge : B : Peg : G, and X : Ge : B : Peg : Ch : G. The produced composite hydrogels were examined for swelling ability, biodegradability, rheological characteristics, and porosity. The 3D structure of the hydrogel was revealed by scanning electron microscopy (SEM). After that, the structural characterization technique named Fourier-transform infrared spectroscopy (FTIR) was used to describe the composites (SEM). Lastly, in a rat skin wound model, the efficacy of the produced hydrogels was studied. Swelling ability, biodegradability, rheological properties, and porosity were all demonstrated in composite hydrogels that contained over 90% water. Hydrogels with good polymeric networks and porosity were observed using SEM. The existence of bound water and free, intra- and intermolecule hydrogen-linked OH and NH in the hydrogels was confirmed using FTIR. In a secondary burned rat model, all hydrogels showed significant wound healing effectiveness when compared to controls. When compared to other composite hydrogels, wounds treated with X : Ge : Peg : Ch : G, X : Ge : B : Peg : G, and X : Ge : B : Peg : Ch:G recovered faster after 28 days. In conclusion, this research suggests that X : Ge : Peg : Ch : G, X : Ge : B : Peg : G, and X : Ge : B : Peg : Ch : G could be used to treat skin injuries in the clinic.

There is an increasing need for materials with tunable physical and chemical properties that are relatively non-toxic and efficacious for their intended application. Many wood stains and finishes emit toxic chemicals which may have serious implications to one’s health. A novel alternative material is realized between xanthan gum and Neodol, a non-ionic surfactant. The resulting three-dimensional film is evaluated as a free-radical scavenger for the protection of wood at different ratios. Atomic force microscopy visualizes the topography and quantifies the local nanomechanics, while rheological measurements showcase a shift from viscoelastic material to gel. Electron plasmon resonance confirms the free-radical reducing ability (3.5 times), while liquid chromatography mass spectroscopy quantifies the UV degradation of sinapyl alcohol. This material has potential, not only in coating industries as a safer option, but also in those industries requiring flexibility and tenability, namely for biosensors and anti-inflammatory therapeutics. Graphic abstract

Instrumental characteristics from extensional rheology and tribology for aqueous xanthan gum (XG) and locust bean gum (LBG) solutions were studied in the presence or absence of simulated saliva. Extensional viscosity was calculated from the filament shrinkage behavior using a capillary breakup extensional rheometer, whereas the friction coefficient was measured using a set-up consisting of polydimethylsiloxane substrate and a glass ball bearing on a rotational rheometer. Increase in extensional viscosity was detected immediately after initiation of extensional flow, particularly XG, and also immediately before the filament rupture, particularly LBG. Extensional viscosity tended to decrease with increased addition of simulated saliva for XG, while to increase for LBG. In both cases, effect of cations in the saliva was greater than that of mucin. From the shape of the Stribeck curve (i.e., dependence of the friction coefficient on the entrainment speed) and comparison of the friction coefficient itself, lubricity of XG was greater than that of LBG. Simulated saliva added decreased the friction coefficient for each polysaccharide through functions of cations rather than mucin. Extensional viscosity and tribological measurements revealed mechanical properties of polysaccharide solutions which cannot be determined or quantified by shear viscosity alone.

The development of eco-friendly corrosion inhibitors is a subject of several investigations, especially natural polymers. Aimed at suppressing the corrosion of L80 steel in 1 mol/L hydrochloric acid (HCl), a novel natural polymer inhibitor was developed based on xanthan gum (XG) and β-Cyclodextrin (β-CD) in this work. The corrosion inhibition effect of β-cyclodextrin modified xanthan gum (β-CD-XG) on L80 steel was evaluated by electrochemical methods, and surface analysis technology. Adsorption isotherm studies, Fourier transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS) were used to explore the corrosion inhibition mechanism of β-CD-XG on L80 steel. The results suggested that β-CD-XG was classified as a mixed-type inhibitor, and mainly suppressed the anode metal dissolution by a tight adsorption film. The formation of the film was attributed to the chemisorption of –OH, –COO-, –CH2–O–, and –CH2–O–CH2– groups on the surface of L80 steel, which conformed to the Langmuir adsorption model. The experimental results illustrated that the maximum corrosion inhibition efficiency of 94.74% was acquired at 200 mg/L β-CD-XG at 293 K.

Summary Interaction between biopolymers generates different rheological behaviors, which can be effective on the structure of food products. One way to control the polysaccharide–protein interaction is the variation of acidic and ionic strength. In this research, the different amounts of pHs (3–7) and calcium chloride (5–20 mM) were investigated on a soluble complex of whey protein concentrate (WPC) with xanthan gum (XG) and basil seed gum (BSG). The complex characteristic was investigated according to turbidity, viscosity behavior, and electrostatic interactions. The turbidity test showed that WPC:BSG and WPC:XG absorbance increased at pH 3.5 and 4.5, respectively, due to the formation of insoluble complex. pH 6 was the start point of the turbidity increment, which showed the formation of soluble complexes between WPC and polysaccharides. The FTIR analysis confirmed creation of soluble complex at pH 6. The absorbance raised with increasing the molar of CaCl2 to 10 mM, but no significant difference was observed by turbidity test in the range of CaCl2, This research paper has been written based on our latest investigation on the creation soluble complex of whey protein concentrate (WPC) with xanthan gum (XG) and basil seed gum (BSG) under different amounts of pHs (3–7) and calcium chloride (5–20 mM). The complex characteristic was investigated according to turbidity, rheological behavior, and electrostatic interactions. The results illustrated although the hydrocolloids had different sources, their functions were approximately similar. The data analysis illustrated that alterations of pH affect soluble and insoluble complexes, and reduced complex viscosity. In addition, the viscosities of complexes had downward trends in the presence of different concentrations of salt. The soluble complex for both hydrocolloids was created in pH 6.

Any improvement in drilling technology is critical for developing the oil and gas industry. The success of drilling operations largely depends on drilling fluid characteristics. Drilling fluids require enough viscosity to suspend the particles and transport them to the surface and enough capability to control the fluid loss into the formation. Rheology and filtration characteristics of drilling fluids are crucial factors to consider while ensuring the effectiveness of a drilling operation. Graphene oxide (GO), xanthan gum (XG), and low-viscosity carboxymethyl cellulose (CMC LV) are being utilized in this research to produce high-performance, low-solid water-based drilling fluids (WDFs). Rheological and filtration behaviors of GO/XG/CMC LV-WDF were investigated as a function of GO, XG, and CMC LV at low concentrations (0.0-0.3% w/w) and atmospheric conditions. According to the findings, GO improved the rheological and filtration capabilities of the WDF. By adding 0.15 wt % GO, shear stress could be doubled, especially at a high shear rate of 1022 s-1. The plastic viscosity of the fluid could be expanded from 6 to 13 centipoise, and a fluid loss of 8.7 mL over 30 min was observed during the API fluid test, which would be lower than the suggested fluid loss value (15.0 mL) for water-based mud. At the same concentration of XG and CMC LV, XG had a more significant influence on rheological characteristics in the presence of GO. Adding 0.3 wt % XG could increase fluid shear stress from 20.21 to 30.21 Pa at a high shear rate of 1022 s-1. In contrast, CMC LV had more impact on filtration properties, acting as a filtration control agent by decreasing the API fluid loss of fluid from 21.4 to 14.2 mL over 30 min. The addition of XG and CMC LV to the GO solution may influence the microstructure of the filter cake, resulting in a tree-root morphology. Indeed, in the GO/CMC LV solution, the individual platelets may bind together, form a jellyfish shape, and block the micropores. The incorporation of CMC LV helped develop compact filter cakes, resulting in excellent filtration. Five rheological models were employed to match the fluid parameters quantitatively. The Herschel-Bulkley model outperformed the other models in simulating fluid rheological behavior. The findings of this study can be utilize to provide low-cost, stable, and environmentally compatible additives for drilling low-pressure, depleted, and fractured oil and gas reservoirs.

Silymarin, is a therapeutically important flavonoid act as a hepatoprotective agent. However, has a positive effect on metabolism act as a hydrophobic drug but has a very low bioavailability. The aim of the present study was to prepare appropriate formulations of Silymarin in order to enhance its bioavailability. The natural suspending agents like (Xanthan gum, Tragacanth gum, Acacia gum and Iranian gum) were used for the formulation of suspensions, while emulsions were prepared with the combination of surfactant, co-surfactant and oil. The formulations were evaluated for their physical stability, pH, refractive index and conductivity. Among different formulations and suspensions prepared with xanthan gum as a green stabilizing agents were most stable. Emulsions formulated with tween 80 as a surfactant, polyethylene glycol as co-surfactant and olive oil were clear and stable for more than six months. The refractive index, pH and conductivity of the most stable suspension and emulsions were 1.347, 6.9 and 0.18 s/m and 1.43, 6.9, 0.01 s/m respectively. It was concluded that xanthan gum and tween 80 with polyethylene glycol has a good potential to enhance the therapeutic efficiency and stability of silymarin suspension and emulsion.

Kelulut honey (KH) is a honey produced by stingless bee species, known for its high nutritional content and health benefits. Even though it is very healthy, some people cannot consume it directly. Therefore, incorporating this type of honey into an emulsion system is a good strategy to increase its consumption. Emulsion technology is one of the alternative technologies nowadays which combines two or more immiscible liquids to form a solution. In this study, KHemulsions were emulsified with glyceryl monostearate (GMS) and stabilised by xanthan gum. There were two stages involvedto determine the effects of variations in oil types and emulsifier concentrations on the physical properties of KH emulsions. In the first stage, three types of oil were used as the dispersed phase, which were palm oil, canola oil, and sunflower oil. Then in the second stage, different concentrations of GMS (0.25, 0.5, 0.75 and 1%) were applied. From the droplet size analysis, the emulsion with sunflower oil and the highest concentration of GMS gave the smallest diameter of 0.78 ± 0.01µm and the lowest polydispersity index (pdI) of 16.2±2.03 %. Meanwhile, the texture analysis shows that emulsion with palm oil has the highest firmness (45.16±2.83 g) and consistency (305.44±14.91 g.sec) values. The foaming index on the other hand depicts that emulsion with palm oil and that with the lowest concentration of GMS gave the highest foam stability. From this study, a physically stable oil-in-water KH emulsion was produced, which should undergo further chemical, sensory and storage studies for commercial production in the future.

The thickening management index for food for dysphagia is important in enabling recognition of the rheological properties of thickened liquids, including their static and dynamic properties. One of the static properties of these liquids is the yield stress. An improvement to the simplified inclined plane test is proposed here that involves use of an automatic system for measurement of the displacements of thickened liquids on an inclined plate. The aim of this study is to investigate the relationship between the displacements of the thickened liquids and the variable thickener concentrations using an optical sensor. To measure the displacement of each thickened liquid on a clear inclined plate, an optical sensor that has a 12-mm-long light receiving surface is selected to form a one-dimensional position-sensitive detector (1D-PSD) under the clear inclined plate. The relationship between the angle of inclination of the plate θ at which the maximum voltage occurred in the 1D-PSD and five thickener (xanthan gum) concentrations c, ranging from 1.0 to 3.0 wt% in steps of 0.5 wt%, was investigated. It was confirmed that an approximately linear plot was obtained under the condition that θ = 8.24 c + 0.18, with the correlation R = .99 (for n = 7). This result indicated that the optical sensor composed of the 1D-PSD can measure the displacements of thickened liquids with various thickener concentrations on the clear inclined plate automatically.

In this study, montmorillonite (MMT)/xanthan gum (XG)-sodium alginate (Alg) hybrid hydrogel nanocomposite has been synthesized for adsorption of malachite green (MG) from aqueous solution. The MMT nanoparticles were modified by cetyltrimethylammonium bromide (CTAB), with specific fraction of the critical micelle concentration (CMC) of CTAB, and applied to synthesize MMT(0.5CMC)/XG-Alg, MMT(1CMC)/XG-Alg and MMT(2CMC)/XG-Alg, and unmodified MMT nanoparticles were applied to synthesis MMT/XG-Alg as control adsorbent. BET, FTIR and SEM analyses were conducted, in order to identify the structure and morphologies of hybrid nanocomposites. The results of FTIR, showed that the functional groups of carboxylates and hydroxyl in the structure of the nanocomposite play an important role in the adsorption process. According to SEM analysis, the unevenness on the adsorbents surface has disappeared, due to the adsorption of the MG dye. Also, by the surface modification of MMT nanoparticles using CTAB, the MMT(0.5CMC)/XG-Alg specific surface area increased from 6.38 to 72.48 m2/g, compared to MMT/XG-Alg. Maximum adsorption capacity was occurred in pH = 6, temperature 318 K, contact time 240 min and 0.02 g/50 mL of the hybrid nanocomposites. According to the results, adsorption process was fitted on the Langmuir isotherm model, with maximum adsorption capacity of 769.23 mg/g for the MMT(0.5CMC)/XG-Alg as the best adsorbent, and 476.19, 666.66 and 588.23 mg/g for the MMT/XG-Alg, MMT(1CMC)/XG-Alg and MMT(2CMC)/XG-Alg, respectively. Adsorption kinetics is well described by the pseudo-second order. The thermodynamic parameters, the enthalpy (∆H°) and Gibbs-free-energy (∆G°), indicated that sorption process was endothermic and spontaneous, respectively.

The volume change and shuttle effect of sulfur are detrimental to the stability and electrochemical performance of the sulfur cathode in lithium–sulfur (Li–S) batteries. In this study, a triple cro...

Antioxidants are used to prevent the oxidation of free radical compounds which have a bad impact on the body, including the skin. One source of antioxidants derived from natural ingredients is Moringa leaves. Moringa leaves have a number of benefits due to the many active chemical compounds. The antioxidant activity of Moringa leaves can be optimized by developing Moringa leaves into a gel dosage form. A literature review regarding the compound content and activity of Moringa leaves was carried out to obtain scientific data that can be used in the development of Moringa leaves as an antioxidant. Narrative review with data sources from Science Direct, Pubmed, CiterSeerX, and Google Scholars. The Inclusion and exclusion criteria were set to obtain literature according to the scope of the study. The results of the literature review showed that Moringa leaves contain the main active compounds of polyphenols and flavonoids which have strong antioxidant activity. Gel dosage form is one of the best choices to optimize the antioxidant activity of Moringa leaves. HPMC, carbopol and xanthan gum are gelling agent was produced a gel preparation with good pharmaceutical characteristics.

Xanthan gum (XG) was widely used as an oilfield chemical treatment agent because of its environmental protection and diverse functions. With the increased drilling depth and formation complexity, the shortcomings such as poor solubility and low resistance to temperature were gradually exposed. In this study, a modified XG derivative XG-g-AAA was synthesized by grafting XG with acrylic acid (AA), acrylamide (AM), and 2-acrylamido-2-methylpropane sulfonic acid (AMPS). The chemical structure of XG-g-AAA was determined by Fourier transform infrared spectroscopy and nuclear magnetic resonance (1H NMR). Then, the solubility, high-temperature rheology and filtration properties, resistance to Na+/Ca2+, and compatibility were investigated. Results show that (1) both in aqueous and salt solutions, XG-g-AAA can completely be dissolved within 15 min. The significant improvement of the solubility of XG-g-AAA makes it more suitable for field use. (2) XG-g-AAA is less sensitive to high temperatures, and the viscosity decay decreased by 23.3 and 21.3% than XG at 150 and 180 °C, respectively. XG-g-AAA-based drilling fluid is a high-quality drilling fluid with significant shear thinning behavior, and the power-law model is the optimal model to describe its high-temperature rheology. Within 150 °C, 1.5% XG-g-AAA can maintain a reasonable value of the flow behavior index (n) (0.55-0.69), filtration volume (

To solve issues of low consolidation strength, poor dust suppression effect, and secondary pollution of the current coal dust suppressors, a greener and higher-consolidation-strength composite dust suppressor was synthesized by the radical polymerization of xanthan gum (XG) as the graft substrate, methyl acrylate (MA), and vinyl acetate (VAc) as the graft monomers. Taking compressive strength as the main optimization index and viscosity and surface tension as the secondary indices, the optimum ratio of MA:VAc was 3:5 and the optimum solid content was 2%. Experiments reveal that the prepared dust suppressant can naturally infiltrate into coal to form a hard solidified layer. At a wind speed of 10 m/s, the solidified layer still maintained structural integrity, indicating that the dust suppressant exhibits a good dust fixation effect. The dust suppressant can not only maintain relatively stable performance for a period of time but also degrade naturally. Furthermore, molecular dynamics simulation reveals not only the interaction mechanism between coal molecules and the dust suppressor but also the wetting mechanism of the dust suppressor. Experimental and simulation results reveal that as a multifunctional dust suppressor with excellent performance, the as-prepared dust suppressor demonstrates the immense potential for the control of coal dust. Graphical abstract.

Most commonly used wound dressings have severe problems, such as an inability to adapt to wound shape or a lack of antibacterial capacity, affecting their ability to meet the requirements of clinical applications. Here, a nanocomposite hydrogel (XKP) is developed by introducing polydopamine nanoparticles (PDA NPs) into a food gum matrix (XK, consisting of xanthan gum and konjac glucomannan, both FDA-approved food thickening agents) for skin wound healing. In this system, the embedded PDA NPs not only interact with the food gum matrix to form a hydrogel with excellent mechanical strength, but also act as photothermal transduction agents to convert near-infrared laser radiation to heat, thereby triggering bacterial death. Moreover, the XKP hydrogel has high elasticity and tunable water content, enabling it to adapt to the shape of the wound and insulate it, providing a moist environment suitable for healing. In-vivo skin wound healing results clearly demonstrate that XKP can significantly accelerate the healing of wounds by reducing the inflammatory response and promoting vascular reconstruction. In summary, this strategy provides a simple and practical method to overcome the drawbacks of traditional wound dressings, and provides further options when choosing suitable wound healing materials for clinical applications., Graphical abstract Image 1, Highlights • The nanocomposite hydrogel has excellent antibacterial activity and rapid shape adaptability. • The nanocomposite hydrogel possesses excellent blood compatibility and cytocompatibility. • The nanocomposite hydrogel varied with the shape of the wound when it was stretched or pressed. • The nanocomposite hydrogel can significantly improve the healing of bacteria-infected wounds.

Summary Water‐soluble polymers (WSPs) are a versatile group of chemicals used across industries for different purposes such as thickening, stabilizing, adhesion and gelation. Synthetic polymers have tailored characteristics and are chemically homogeneous, whereas plant‐derived biopolymers vary more widely in their specifications and are chemically heterogeneous. Between both sources, microbial polysaccharides are an advantageous compromise. They combine naturalness with defined material properties, precisely controlled by optimizing strain selection, fermentation operational parameters and downstream processes. The relevance of such bio‐based and biodegradable materials is rising due to increasing environmental awareness of consumers and a tightening regulatory framework, causing both solid and water‐soluble synthetic polymers, also termed ‘microplastics’, to have come under scrutiny. Xanthan gum is the most important microbial polysaccharide in terms of production volume and diversity of applications, and available as different grades with specific properties. In this review, we will focus on the applicability of xanthan gum in agriculture (drift control, encapsulation and soil improvement), considering its potential to replace traditionally used synthetic WSPs. As a spray adjuvant, xanthan gum prevents the formation of driftable fine droplets and shows particular resistance to mechanical shear. Xanthan gum as a component in encapsulated formulations modifies release properties or provides additional protection to encapsulated agents. In geotechnical engineering, soil amended with xanthan gum has proven to increase water retention, reduce water evaporation, percolation and soil erosion – topics of high relevance in the agriculture of the 21st century. Finally, hands‐on formulation tips are provided to facilitate exploiting the full potential of xanthan gum in diverse agricultural applications and thus providing sustainable solutions.

Xanthan gum (XG), a bacterial polysaccharide has numerous valuable characteristics in the food, biomedical, pharmaceuticals, and agriculture sector. However, XG has also its particular limitations such as its vulnerability to microbial contamination, inadequate mechanical and thermal stability, unusable viscosity, and poor water solubility. Therefore, XG's structure and conformation need to be modified enzymatically, chemically, or physically to improve its optimistic features and decrease the formation of crystals, increase antioxidant ability, and radical scavenging activity. We have found out different means to modify XG and elaborate the importance and significance of the modified structure of XG. In this review, different enzymes are reviewed for XG degradation, which modifies their structure from different points (main chain or side chain). This article also reviews various physical methods (ultrasound, shear, pressure, sonication, annealing, and heat treatments) based on prevailing publications to alter XG conformation and produce low molecular weight (LMW) and less viscous end-product. Moreover, some chemical means are also discussed that result in modified XG through crosslinking, grafting, acetylation, pyruvation, as well as by applying different chemical agents. Overall, the current progress on XG degradation is very auspicious to develop a new molecule with considerable uses, in various industries with future assessments.

PAM is a good flocculant, and XG is a good tackifier. When the two solutions are mixed, the PAM/XG mixed solution has good viscosity and can be used as a foam stabilizer in foam drilling fluids, and it can also be used as a coupling agent for sand-fixation serous fluid. When metal cations enter the PAM/XG system, it will destroy the overall rheology and stability of the PAM/XG system. This article uses the DV3T-LV rheometer to test the rheology of different types of PAM (HPAM/CPAM/AMPAM/NPAM) and XG mixed solutions,and get the optimal test ratio. Then add various metal cations (Na+, K+, Ca2+, Mg2+) to the mixed solutions of HPAM/XG, CPAM/XG, AmPAM/XG, NPAM/XG respectively. We know divalent metal cations have greater impacts on the shear stress of the PAM/XG composite system, which is likely to cause its shear dilution. Finally, through mechanism analysis, it is concluded that it provides a good preliminary foundation for the research of foam drilling fluid and sand-fixation serous when the metal ion destroys the molecular structure of the PAM/XG composite system.

Time-temperature integrators (TTIs) based on aqueous enzyme solutions produce transparent colors which lead to difficulty in distinguishing its color change by naked eye. In this present study, this issue has been solved by increasing the opacity of laccase-based TTI without changes in the kinetics (same zero-order reaction) and temperature dependency (similar Arrhenius activation energy values) of the color change. The opacity was increased by introducing TiO2, latex, BaSO4, or ZnO, in combination with a hydrocolloid (xanthan gum, acacia gum, pectin, and CMC) into the TTI system. The combination of TiO2 and xanthan gum was the best. This finding broadened the advantages of laccasebased TTI to more practical uses for consumer convenience.

3D food printing is a digitally controlled process in which food materials are deposited by the number of layers placed one above the other. The extrusion-based printers are commercially used for 3D food printing into the various innovative designs for personalized food products. The present review is compiled based on investigations in extrusion-based 3D food printing emphasis on the characteristics of materials (cereal, starch, protein gel, dairy based, and non-native materials), printer control parameters, printing stability, and post-processing practices. Besides, the key aspects of technological advancements of 3D food printers and the major industrial challenges of 3D food printer are discussed. Recent research evidence that the extrusion-based 3D food printing greatly impacts on material characteristics, i.e., rheological, textural, morphological, and the printer control parameters. Formulations and printing conditions play a significant role to retain the structure of the 3D food product. Moreover, different food additives like xanthan gum, methylcellulose, and κ-carrageenan show a positive influence on printing stability. Post-processing, i.e., drying, baking, steaming, frying, etc., are the key challenges to retain the original shape of the 3D printed product. In addition, the potential of the 3D printer for customization of food product, the prospect for the research development and future scope that will bring the high benefit of the imminent researcher and the food industry.

A low carbohydrate and high fat (LCHF) flour was developed by combining almond flour, desiccated coconut flour, defatted soya flour, dry gluten powder, psyllium husk and skimmed milk powder. Determination of rheological, bread making, nutritional, and staling characteristics of LCHF flour in comparison with wheat flour (WF) was studied. The results showed that LCHF flour had lower amylograph pasting temperature (31.6 °C), peak viscosity (200 BU), farinograph dough stability (0.8 min), and bread volume (315 ml) compared to WF (61.0 °C; 782 BU; 8.7 min; and 525 ml) respectively. The use of additive mixes such as fungal alpha-amylase, sodium stearoyl-2-lactylate and xanthan gum, improved the volume and texture of the LCHF bread. Scanning electron microscope images showed little or no presence of starch granules in LCHF dough and bread. Differential scanning calorimetry studies indicated that, during storage (1–5 days), the enthalpy for gelatinization of endotherm starch increased (0.71–3.40 j/g) in WF bread, however, in LCHF bread this increase was lesser (0.53 to 2.2 j/g) indicating slower staling rate in LCHF bread. The LCHF bread showed lower carbohydrate (13.7%), in-vitro starch digestibility (17.3%) and staling rate, higher protein (22.51%), fat (11.01%), and medium-chain fatty acids than WF bread (51.9%; 38.2%; 12.57%; 3.78%) respectively. The results showed that the developed product would be beneficial for people suffering from diabetics and obesity.

The importance of conformational rigidity on macroscopic rheological properties was revealed using two model polysaccharides, namely, xanthan gum and hyaluronic acid. Xanthan gum has a rigid tertiary conformation due to its ordered double-helical structure, and the interactions between the tertiary structures result in the formation of a network/quaternary structure. In comparison, hyaluronic acid possesses a relatively flexible tertiary conformation due to its secondary random coil structure. Xanthan gum exhibits a much stronger shear thinning and more solidlike behavior compared to hyaluronic acid, owing to its network/quaternary structure. The rigid tertiary structure and the presence of a network/quaternary structure also endow xanthan gum with better resistance against environmental changes (e.g., salt and/or urea addition, temperature change) compared to hyaluronic acid. The network/quaternary structure allows xanthan gum to form gels with chitosan via electrostatic interactions when using the vapor-induced gelation technique, which is not possible for hyaluronic acid due to its flexible tertiary conformation under similar conditions.