Marine Archaeal Extracellular Polymeric Substances from Halococcus AMS12, Their Characterization, and Biological Properties

Abstract

In the present study, halophilic archaea were isolated from a marine sediment sample. Totally, 15 isolates (AMS 1–15) were identified by molecular identification as belonging to the ten genera. Further, their extracellular polymeric substances (EPS) were extracted (3.172 g/L), and their bioactivity was determined in terms of biosurfactant, emulsification, enzymatic and non-enzymatic antioxidants, and anticancer activity. The highest amount of EPS has been produced by Halococcus sp., AMS12. It is made up of 54.28% carbohydrates, 32.91% proteins, 2.41% lipids, and other compounds. Further, EPS has 43.69 ± 1.89 U/mg of gelatinase enzyme by degrading the substrate. The potential total antioxidant activity of 103.80 ± 0.02 (ascorbic acid equivalence (AAE)), total reducing power of 86.1 ± 0.25 AAE, 1,1-diphenyl-2-picrylhydrazyl (DPPH) activity of 97.23 ± 0.21%, the hydrogen peroxide scavenging of 60.8 ± 0.21%, and nitric oxide scavenging activity of 89.37 ± 0.24% were observed at 100 μg/mL of EPS. Hence, we conclude that the archeal EPS is multifunctional and useful for developing natural polymers for industrial, food, and pharmaceutical applications.