# Microbial Biopolymers: From Production to Environmental Applications--A Review
## 2 Microbial Polymers
### Bacterial Cellulose  
Waste, including agricultural residue, food waste, and industrial leftovers, can give bacteria the nutrients and habitat they need to create bacterial cellulose. Examples of raw materials used for obtaining bacterial cellulose are by-product streams from sugarcane jaggery waste [71] waste streams from biodiesel and confectionery industries [72], oat hull [73], rice bark [74], corn stalk [75], fruit juices [76], Nylon 6-6 hydrolysate [77], cotton-based textile waste [78], the wastewater of fermentation industries [79], etc. Bacterial cellulose is chiefly isolated by both Gram-positive bacteria and Gram-negative bacteria such as _Komagataeibacter_ spp. _Acetobacter_ spp., _Sarcina ventriculi, Pseudomonas_ spp., etc. [15; 80; 81]. In comparison to plant-derived cellulose, cellulose produced by bacteria offers a range of amenities, which include high levels of purity, superior mechanical and thermal attributes, long-term sustainability, better water- and oil-holding capacities, high surface areas, and biodegradable attributes [82; 83]. Bacterial cellulose is a linear-chain polysaccharide made up of repeating glucose monomeric units linked by \(\beta\) (1-4) linkages. It has a complex structural arrangement with ample hydroxyl groups and robust intermolecular interactions that hamper it from dissolving in water. It is remarkably resistant to decomposing in water because it establishes an interconnected system of linked strands of cellulose, which are bound jointly by bonds of hydrogen [84]. There are some challenges involved in scaling up bacterial-cellulose production by fermentation. Agitated fermentation and static fermentation are both viable methods for producing Bacterial cellulose. [PERSON] [85] investigated that bacterial cellulose produced by static fermentation is a more laborious and lengthy process than agitated fermentation, also static fermentation provides poor yield as compared to agitated fermentation. [PERSON] [85] also concluded that due to the high cost of bacterial-cellulose production, its application is limited as compared to plant-based cellulose. Consequently, novel affordable nutrient sources such as fermentation effluent, sugarcane molasses, and waste from fruits could additionally be utilized for the bacterial-cellulose upscaling manufacturing process. The manufacturing process of bacterial cellulose and its commercial usage has been constrained by high production costs as well as low yield. Bacterial cellulose-producing bacteria have no capacity to co-produce additional compounds with cellulose, such as lignin, pectin, and hemicellulose. Bacterial cellulose has a significant purity advantage over cellulose generated from plants. Furthermore, bacterial cellulose is biocompatible since complementary polymers and other contaminants are absent from it [86]. Due to its biocompatibility and biodegradability, it offers wide applications. [PERSON] et al. [87] developed a filter based on bacterial cellulose for the elimination of oil from wastewater. Their findings suggested that bacterial cellulose could be used as an alternative material for oil filter development. [PERSON] et al. [88], [PERSON] et al. [89], and [PERSON] et al. [90] utilized bacterial cellulose as a biomaterial to improve the ductility, tensile strength, biocompatibility of composites. Similarly, [PERSON] et al. [91] made filter membranes from bacterial cellulose for industrial water treatment. Based on bacterial cellulose, various potential biosensors have been developed for multifarious applications [92]. Some were developed for the detection of bacteria and viruses [56; 93], antibiotics [94], heavy metals [57; 95], dyes [96], and pollutants [97]. Moreover, many researchers have investigated bacterial cellulose-based hydrogels for the removal of heavy metals and dyes [98; 99; 100].