Bacterial exopolysaccharides from extreme marine habitat of Southern Ocean: Production and partial characterization

Abstract

Deep marine microorganisms survive under extreme ecological settings and harsh environmental conditions of low temperature, high salinity, and high atmospheric pressure making it significant of scientific interest. Southern Ocean (SO) is one such example of deep marine ecosystem and the microorganisms inhabiting in such hostile environment may produce different bioactive secondary metabolites. SO (Indian Sector) is relatively less documented in terms of microbial composition and community dynamics. The present study involves isolation of exopolysaccharides (EPSs) from three potent SO (Indian Sector) bacteria, optimization of the EPS production and partial characterization of them. Three different EPSs show varying structural conformation, that is from porous to strong flakes mimicking polymeric structure with C/N ratio ranging between 4-11. FTIR spectra have exhibited the presence of different active groups of carbohydrate moieties, water molecules and protein-associated amides. EPSs produced by marine microorganisms show high biotechnological promises such as drug carrier in pharmaceutical field, emulsifier and cryoprotectant in food-processing industry, detoxification of petrochemical oils and much more. The three bacterial isolates in this study showed potential of producing EPS biopolymer that can be further explored in terms of its proper biotechnological applications.

Novel phenolic compound from Southern Ocean microalgae Chlorella sp. PR-1 and its antibacterial activity

“…PR1 was isolated as a part of Southern Ocean (Indian sector) expedition 2011. Because of relatively fewer reports on biology of Southern Ocean microorganisms, this habitat is an example of one of the least explored ecosystem on earth with immense future possibilities (Banerjee et al 2019). In this study, CCl 4 fraction of the marine microalgae Chlorella sp.…”

“…Ocean offers infinite biodiversity potential most of which are still uncharacterized and may eventually develop into novel therapeutics (Newman & Cragg 2012, Gupta et al 2015. Southern Ocean (Indian sector) harbors affluent microbial diversity that are promising source of unique bioactive compounds (Banerjee et al 2019, Sengupta et al 2019. Hence, they are of great scientific interest and make Southern Ocean as incipient biomedical resource (Chin et al 2006, Harvey 2008.…”