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The extracellular heteropolysaccharide xanthan, synthesized by bacteria of the genus Xanthomonas , is widely used as a thickening and stabilizing agent across the food, cosmetic, and pharmaceutical sectors. Expanding the scope of its application, current efforts target the use of xanthan to develop innovative functional materials and products, such as edible films, eco-friendly oil surfactants, and biocompatible composites for tissue engineering. Xanthan-derived oligosaccharides are useful as nutritional supplements and plant defense elicitors. Development and processing of such new functional materials and products often necessitate tuning of xanthan properties through targeted structural modification. This task can be effectively carried out with the help of xanthan-specific enzymes. However, the complex molecular structure and intricate conformational behavior of xanthan create problems with its enzymatic hydrolysis or modification. This review summarizes and analyzes data concerning xanthan-degrading enzymes originating from microorganisms and microbial consortia, with a particular focus on the dependence of enzymatic activity on the structure and conformation of xanthan. Through a comparative study of xanthan-degrading pathways found within various bacterial classes, different microbial enzyme systems for xanthan utilization have been identified. The characterization of these new enzymes opens new perspectives for modifying xanthan structure and developing innovative xanthan-based applications. Key points • The structure and conformation of xanthan affect enzymatic degradation. • Microorganisms use diverse multienzyme systems for xanthan degradation. • Xanthan-specific enzymes can be used to develop xanthan variants for novel applications.

The limited use of xanthan (Xa) and carboxymethyl cellulose (CMC) in the food packaging industry is due to their poor barrier and antimicrobial properties. The objective of this work was to enhance the characteristics of the CMC/Xa composite coating by incorporating ZnO nanoparticles (ZnO-NPs) that were prepared through a green method through Coriandrum sativum extract. FTIR and XRD confirmed the successful preparation of the coating and verified the interactions between its components. Compared to the neat CMC/Xa system, systems incorporated with ZnO-NPs exhibited excellent water barrier, mechanical, thermal, and antimicrobial characteristics. The CMC/Xa/ZnO-NP systems effectively prolonged the shelf life of tomatoes for a storage period of 20 days without any significant indications of spoilage or mass loss of the coated tomatoes. The obtained results indicated that the developed coating has the potential to replace traditional plastic packaging and effectively preserve food products.

Recently, microbial biopolymer-based soil treatment (BPST) has gained attention for its application in environmentally friendly soil stabilization, particularly for enhancing the strength and stability of fine-grained soils. However, the effects of BPST on clay’s compressibility (consolidation) and expansion (swelling) behaviors remain unclear. This study used xanthan gum, a microbially produced polysaccharide with anionic charges, to stabilize kaolinite clay. The effect of xanthan gum BPST on the consolidation and swelling behavior of cohesive kaolinite clays was assessed through a series of experimental tests, including one-dimensional consolidation tests with elastic wave measurements, swelling tests, environmental scanning electron microscopy, and unconsolidated-undrained triaxial tests. The formation of xanthan gum hydrogels induces pore-clogging, resulting in a delay in the consolidation process, increased energy dissipation, and compressibility. Furthermore, the interaction between kaolinite and xanthan gum improved the undrained shear strength of kaolinite soils, thereby reducing the consolidation time required for a specific bearing capacity. This study demonstrates the possible application of controlling hydraulic conductivity, seismic stabilization, and rapid surface stabilization. However, additional drainage is necessary for in situ applications.

This study aims to accurately predict the drag reduction rate of xanthan gum in hydraulic fracturing to enhance efficiency and safety. We use experimental and theoretical methods. First, we conduct drag reduction tests with xanthan gum in a lab-scale pipeline under various conditions. Then, we analyse the effects of Reynolds number and polymer concentration on drag reduction. We develop a two-factor-interaction empirical model using surface response methodology, incorporating Reynolds number and polymer concentration. The model is validated through quantitative analysis. Results show that within a certain range, higher Reynolds number and polymer concentration lead to greater drag reduction. The model effectively predicts drag reduction rates across different conditions, providing a basis for xanthan gum application. Accurate prediction helps optimize fracturing fluid designs, improve efficiency, and reduce costs.

Asphaltene precipitation in carbonate reservoirs presents a significant flow assurance challenge. This study investigates a novel ZnO/SiO₂/xanthan/eucalyptus nanocomposite (NCs) for inhibiting asphaltene deposition. A multiscale analysis was employed, incorporating adsorption isotherms, atomic force microscopy (AFM). and core-flooding under realistic reservoir conditions (90 °C, up to 3700 psi). Adsorption isotherm analysis confirmed that the Langmuir model provided the best data fit, indicating monolayer adsorption with a high capacity (Q m  = 185.2 mg/g). Interfacial tension (IFT) measurements demonstrated NCs altered the IFT-pressure slope by 45.71%, indicating enhanced inhibition. AFM analysis revealed NCs significantly reduced surface roughness, decreasing average roughness (R a ) from 56.70 to 11.42 nm. Core-flood experiments confirmed NCs mitigated permeability impairment by over 50% and reduced asphaltene precipitation by up to 4.00 wt.% during natural depletion. The results demonstrate that the synthesized NCs are a highly effective inhibitor for mitigating asphaltene-related formation damage in carbonate reservoirs.

Xanthan gum biopolymers have gained increasing attention in geotechnical engineering due to the effectiveness and environmental-friendliness, and are proposed as a potential alternative to conventional materials for soil stabilization. Cyclic wetting and drying are the crucial factors that affect the behavior of surface soil, which are also a major challenge for biopolymer applications. This study aims to investigate the strength durability of xanthan gum-treated soil during wetting–drying cycles. The soil was treated with different contents of xanthan gum (0, 0.5, 1.5% by the mass of dry soil) and a total of 12 wetting–drying cycles were applied. Unconfined compression tests were performed to evaluate the changes in soil mechanical properties. The changes in microstructure were observed using nuclear magnetic resonance technology and scanning electrical microscopy. The results showed that soil mechanical properties decreased significantly in the first four cycles, and then tended to equilibrium. The compressive strength of soil treated with 1.5% xanthan gum could be approximately twice than that of non-treated soil after 12 cycles, and its strength reduction caused by wetting–drying cycling is about 20% less than that of the latter. When increasing the water content at drying stage, specimens subjected to wetting–drying cycles with less moisture change presented higher compressive strength, in which case the effectiveness of biopolymer treatment can be maximally retained. Xanthan gum treatment conferred great resistance to wetting–drying cycling due to its cementation and aggregation effects. The presence of xanthan gum leads to more inter-aggregate pores with a radius of about 0.1–1 μm and limits the development of macropores. The strengthening effect of xanthan gum depends on direct clay particle–biopolymer interactions and inter-particle connection formed by xanthan gum matrix. From the results, xanthan gum biopolymers can significantly improve the mechanical properties of soil at shallow depth even after wetting–drying cycles.

Hydrogels are considered to be the most ideal materials for the production of wound dressings since they display a three-dimensional structure that mimics the native extracellular matrix of skin as well as a high-water content, which confers a moist environment at the wound site. Until now, different polymers have been used, alone or blended, for the production of hydrogels aimed for this biomedical application. From the best of our knowledge, the application of a xanthan gum–konjac glucomannan blend has not been used for the production of wound dressings. Herein, a thermo-reversible hydrogel composed of xanthan gum–konjac glucomannan (at different concentrations (1% and 2% w/v) and ratios (50/50 and 60/40)) was produced and characterized. The obtained data emphasize the excellent physicochemical and biological properties of the produced hydrogels, which are suitable for their future application as wound dressings.

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. Synthetic water‐soluble polymers are used for different purposes in agriculture, but there are increasing concerns regarding their environmental impact. Microbial polysaccharides obtained by industrial fermentation are a sustainable, eco‐friendly alternative with precisely controlled material characteristics. This is shown on the example of xanthan gum applied for soil improvement, drift control and encapsulation.

The effect of various concentration of xanthan gum (0.5%, 1%, and 2%) based edible coating supplemented with pomegranate peel extract (0.5 mL) on functional and physico-chemical properties of mango ( Mangifera indica L.) fruits were studied during the storage period of 15 days at 22 °C. The application of xanthan gum (XG) based edible formulations with pomegranate peel extract (PPE) was found to be effective to maintain the quality attributes and characteristics like reducing weight loss, respiration rate, ethylene production, maintained total soluble solids (TSS), acidity, pH, texture property, ascorbic acid, phenols, and antioxidant activity as compared to control samples. In general, all tested formulations are effective; but edible coatings based on 2% of XG were found the most potential to prevent the postharvest characteristics of mango fruits while maintaining the quality attributes.