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Exopolysaccharide (EPS) is a straight/branched biopolymer consisting of sugar units and their derivatives. This sugar unit consists of glucose, galactose, mannose, N-acetylglucosamine, N-acetyl galactosamine, rhamnose, and fructose. EPS is very interesting biomaterial to be studied because it has many advantages such as nontoxic, water soluble, biodegradable and has many applications. EPS has been widely applied in various industrial fields, such as in the food industry, which is used as an emulsifier in cheese, bread, and milk-based production; while in pharmaceuticals industries, it has been used as a material for drug delivery system; and in bioindustry, it is used for enzyme immobilizer. In this study, EPS-producing halophilic bacteria have been screened from a salty lake Gili Meno Lombok, NTB, Indonesia. This study aims to perform a selection of a potential EPS-producing halophilic bacterium, identify its bacterial species, production of EPS and the application of EPS as a nanomaterial for protein immobilization. The EPS produced by the isolates from the selection above was verified by FTIR and NMR spectroscopy techniques. The results of the structure characterization showed that EPS produced by one Gili Meno bacterial isolate was inulin. This potential inulin producing bacterium closed to Salinivibrio costicola based on its16s rDNA sequence and the result of phylogenetic analysis so that it was named in this study as Salinivibrio costicola GM01. Inulin produced by this bacterium was used as a medium for protein immobilization in the form of nanoparticles. The immobilized protein target was lipase. The efficiency of lipase immobilized on nanoparticles were 81%. The SEM image of lipase-inulin nanoparticles showed spherical morphological shape with the diameter about 218−886 nm according to particle size analyzer (PSA) measurement. The zeta potential of the nanoparticle was about +0.03 mV. The respective lipase activity before and after the immobilization was 0.36 ± 0.010 units/mg and 0.28 ± 0.002 units/mg. These results showed that the inulin-based nanoparticle can provide compatible environment for lipase since its activity can be maintained about 80%.