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

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 mu g/mL of EPS. Hence, we conclude that the archeal EPS is multifunctional and useful for developing natural polymers for industrial, food, and pharmaceutical applications.

Automated summary

In this study, halophilic archaea were isolated from a marine sediment sample. Their extracellular polymeric substances (EPS) were extracted and evaluated for various bioactivities. The EPS produced by Halococcus sp., AMS12 showed the highest amount and exhibited enzymatic, antioxidant, and anticancer activities. These findings suggest the multifunctionality of archaeal EPS for potential industrial, food, and pharmaceutical applications.