Biopolymer Xanthan gum (XG), an exo-polysaccharide obtained from the fermentation of simple sugars by bacteria Xanthomonas campestris under aerobic conditions exhibits interesting properties like biodegradability, high viscosity at a low shear rate and stability under a wide range of temperature and pH. These characteristics properties render it accessible to utilize as a stabilizer, suspending as well as an emulsifying agent in food industries, petroleum and oil refining industries, cosmetic industries, and as an adsorbent in wastewater treatment. However, XG hydrophilicity and water solubility characteristics not only restrict its application domain but also affect its thermal stability during processing. Therefore, the efforts are directed to improve its application spectrum by modifying the physical and chemical characteristics of biopolymer, taking advantage of the presence of different amenable functional moieties in XG. The chemical modifications of XG include the formation of cross-linked polymers, grafting of monomer to base polymers manipulating the functionality by removal/addition of chemical groups. Currently, the emphasis is on the development of XG based grafted/crosslinked bionanocomposites which can be tailored as a noble adsorbent for wastewater treatment for the remotion of toxic metals, coloured synthetic dyes and other industrial effluents from the aqueous medium. The emphasis of present review article is to address the structural, physical characteristics along with the focus on the development of chemically modified XG viz. grafted, crosslinked, nanocomposites, and functionally modified biopolymer. The potential applications of these modified XG polymers for phasing out synthetic dyes and transition metals ions from aqueous systems have been deliberated.

生物聚合物黄原胶（XG）是一种由细菌黄单胞菌在有氧条件下发酵单糖发酵得到的外多糖，具有有趣的特性，如可生物降解性，低剪切速率下的高粘度以及在宽温度和pH范围内的稳定性。这些特性使它易于在食品工业，石油和炼油工业，化妆品工业中用作稳定剂，悬浮剂和乳化剂，并在废水处理中用作吸附剂。但是，XG的亲水性和水溶性特征不仅限制了其应用领域，而且还影响了其在加工过程中的热稳定性。因此，我们致力于通过修改生物聚合物的物理和化学特性来改善其应用范围，利用XG中不同的可适应功能部分的存在。XG的化学修饰包括形成交联聚合物，将单体接枝到基础聚合物上（通过移除/添加化学基团来控制功能）。当前，重点是开发基于XG的接枝/交联的生物纳米复合材料，该复合材料可定制为用于废水处理的贵族吸附剂，用于从水性介质中去除有毒金属，有色合成染料和其他工业废水。本文的重点是解决结构，物理特性以及化学修饰XG viz的开发。接枝，交联，纳米复合材料和功能改性的生物聚合物。