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Besides the above mentioned microbial gums, there are several other gums produced from microbial sources; a few examples are as follows.

Scleroglucan is an EPS produced by fungus Sclerotium glucanicum. It is HoPS of glucose linked by β‐(1,3) and β‐(1,6) linkages where every third glucose is connected by β‐(1,6) linkages. The molecular mass of scleroglucan can vary from strain to strain. The average molecular weight ranges between 320 and 6000 kDa [24]. It is used as thickeners, stabilizers, and gelling agents in food products due to its resistance to temperature, hydrolysis, and electrolytes. It can inhibit syneresis in starch‐based foods that occur during refrigeration. It is also used in oil recovery operations in the sea [12].

Curdlan is a β‐glucan composed of glucose monomer linked by β‐(1,3) linkages. Curdlan is produced by bacterium Alcaligenes faecalis. Curdlan is not soluble in water or acidic solution but is only soluble in alkaline pH. Curdlan forms two types of gels at different temperatures: (i) high‐set gel (at above 80 °C) and (ii) low‐set gel (between 60 and 80 °C) [2]. The high‐set gel of curdlan is used in food products, as it is a thermo‐irreversible gel and stable during deep‐fat frying and freeze‐thawing. Curdlan is used in low‐calorie foods, as a fat replacer and in food products like freezable tofu noodles [6].

Levan is a HoPS composed of fructose units linked by β‐(2,6) linkages in the main chain with β‐(2,1) linked branches. Levan has been reported to be produced by a wide range of microbes such as Bacillus subtilis, Bacillus polymyxa, Aerobacter levanicum, Leuconostoc mesenteroides, Streptococcus sp., Pseudomonas sp., and Corynebacterium laevaniformans. Levan has a molecular weight of 2–100 MDa that varies between producer organisms. Levan is used in food, pharmaceutical, and cosmetic industries. It is used as stabilizing, emulsifying, and sweetening agents in food products. In the cosmetic industry, levan is utilized for its moisturizing effect, cell proliferation effect, and anti‐inflammatory effects [12].

Dextran is a type of α‐glucan, which consists of a linear chain of α‐(1,6) linked D‐glucose units with various branched linkages at α‐(1,2), α‐(1‐3), and α‐(1‐4) positions of D‐glucose [25]. The degree of branching and molecular weight of dextran varies with dextransucrase enzyme and producers strain. Dextran is commercially available in different molecular weights and is commonly used as molecular weight standards in GPC analysis. Dextran is used in the food industry as a food hydrocolloid and is prebiotic in nature [26].

Alginate, an important gum, is a copolymer of D‐mannuronic acid and L‐guluronic acid. It is usually produced by brown algae. However, alginate is also produced by bacterial sources like Azotobacter vinelandii, Azotobacter chroococcum, and several species of Pseudomonas. These are called bacterial alginates. Bacterial alginates are used in pharmaceutical industries due to their high purity, and they possess immunomodulatory activity [37].

Carrageenan is a gel‐forming biopolymer produced by edible red seaweed (algae). It is composed of alternating units of D‐galactose and 3,6‐anhydro‐galactose joined by α‐1,3 and β‐1,4‐glycosidic linkage. On the basis of their solubility in potassium chloride, carrageenans are classified into λ, κ, ι, ε, μ–carrageenans. They have average molecular weight of above 100 kDa with 15–40% ester sulfate groups. Carrageenan has been reported to possess immunomodulatory, anticoagulant, antithrombotic, antiviral, and antitumor effects [38].