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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.

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.

Proper identification and differentiation of natural polysaccharides is a very crucial task owing to some similarities in their appearance and properties. This research presents an extensive use of FTIR, a well-established and authenticated tool, for identifying and differentiating different classes of gums. Commercially important natural gums including plant exudate gums, seed gums, seaweed gums, microbial gums and animal gums were chosen for the study. For plant exudate gums, a peak at 1424 cm− 1 is common to all, which is absent in other classes of gums. A shoulder peak at 1728 cm− 1 and an ester group vibration peak at 1075 cm− 1 make gum karaya different from other gums. Peaks at 1647 cm− 1 and 1384 cm− 1, common to all seed gums, are absent in other gums and help to set identifying criteria for seed gums. In microbial gums, xanthan and gellan have no peaks in the range of 755–775 cm− 1, unlike other gums. In the case of animal gums (chitosan and gelatin) an intense sharp peak at 1636 cm− 1 is attributed to CONH2 group. Similarly, the paper explains characteristic peaks for gellan, carrageenan, agar, sodium alginate and other gums. Along with the in-depth discussion of major gum’s FTIR, this paper also endorses FTIR as a potential technique for identifying and differentiating natural gums.

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.

Xanthan gum, a natural heteropolysaccharide produced by Xanthomonas species , has many biotechnological applications across industries due to its unique rheological properties. Expanding its utility requires specific enzymes capable of targeted xanthan modification or degradation. In this study, a novel bacterial strain, isolated from a spoiled xanthan sample and identified as Paenibacillus taichungensis I5, was shown to degrade xanthan using a plate screening assay with Congo red. Activity tests of crude enzyme in culture supernatant demonstrated the secretion of xanthan-degrading enzymes. Genome and proteome analyses suggest a chromosomal xanthan utilization locus encoding a suite of enzymes, including a xanthanase (Pt_XanGH9), two xanthan lyases (Pt_XanPL8a and Pt_XanPL8b), two unsaturated glucuronidases, two α-mannosidases, as well as transport and regulator proteins. Functional characterization through recombinant protein expression and enzyme assays confirmed the functions of Pt_XanGH9, Pt_XanPL8a and Pt_XanPL8b on native xanthan and xanthan-derived oligosaccharides. The polysaccharide degradation products released by these enzymes were identified via LC–MS analysis and suggested two xanthan lyases with divergent cleavage preferences. In contrast to Pt_XanPL8a, Pt_XanPL8b is synthesized with an N-terminal signal peptide, yet both lyases were detected in cell-free supernatant during growth on xanthan. Based on the composition of the xanthan utilization gene cluster and preliminary enzyme characteristics, a working model for xanthan utilization by P. taichungensis I5 is proposed. Reaching a better understanding of bacterial xanthan degrading pathways and the enzymes involved may help to develop modified xanthan derivatives and xanthan degrading enzymes that align with the specific demands of various industrial process. Key points • The genome of P. taichungensis I5 encodes a xanthan utilization locus. • P. taichungensis I5 employs a twin lyase-dependent xanthan utilization system. • The two xanthan lyases differ in cellular localization and in cleavage specificity.

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.

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.

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.

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.