Fermentation Technologies for the Optimization of Marine Microbial Exopolysaccharide Production

Abstract

In the last decades, research has focused on the capabilities of microbes to secrete exopolysaccharides (EPS), because these polymers differ from the commercial ones derived essentially from plants or algae in their numerous valuable qualities. These biopolymers have emerged as new polymeric materials with novel and unique physical characteristics that have found extensive applications. In marine microorganisms the produced EPS provide an instrument to survive in adverse conditions: They are found to envelope the cells by allowing the entrapment of nutrients or the adhesion to solid substrates. Even if the processes of synthesis and release of exopolysaccharides request high-energy investments for the bacterium, these biopolymers permit resistance under extreme environmental conditions. Marine bacteria like Bacillus, Halomonas, Planococcus, Enterobacter, Alteromonas, Pseudoalteromonas, Vibrio, Rhodococcus, Zoogloea but also Archaea as Haloferax and Thermococcus are here described as EPS producers underlining biopolymer hyperproduction, related fermentation strategies including the effects of the chemical composition of the media, the physical parameters of the growth conditions and the genetic and predicted experimental design tools.

Implications for public health demands alternatives to inorganic and synthetic flocculants: bioflocculants as important candidates

“…This is actually the research focus in biotechnology, paying attention to studies relating to the genomic level of bioflocculant‐producing microorganisms (Finore et al. ). Once the whole genome of these microorganisms has been sequenced, it will be suitable to select an appropriate tactic to improve the bioflocculant produced by manipulating those genes encoding the enzymes implicated in the bioflocculant synthesis (Yang et al.…”

Antioxidant and Antimicrobial Activities of Exopolysaccharides from Yoghurt Starter

“…Many species of bacteria possess the ability to synthesize and excrete extracellular polysaccharides (exopolysaccharides, EPS) [3]. The bacterial exopolysaccharides are widely used in food, pharmaceutical and chemical industries as bioflocculants, bioabsorbents, drug delivery agents, etc [4]. Lactic acid bacteria (LAB) are able to produce exopolysaccharides (EPSs) in the surrounding medium as a slime or on the surface of bacterial cells to form a capsule [5].…”

An Overview on Marine Sponge-Symbiotic Bacteria as Unexhausted Sources for Natural Product Discovery

“…Although we know that these sponge bacteria can produce novel compounds, the compounds might only be produced under conditions specific to the marine-sponge environment (e.g., certain salt concentration, hydrostatic pressure, competition by other microorganisms and marine nutrients) and not under standard laboratory conditions. In the laboratory, fermentation of marine bacteria within liquid growth media has been the main method used to try and activate compound production [145,150,151] but standard laboratory fermentation conditions (that do not possess these specific sponge-marine conditions) may not be conducive to triggering the expression of all bacterial biosynthetic pathways involved in the production of the potentially novel compounds [14]. However, the fermentation of cultivable sponge-symbiotic bacteria in the laboratory is a highly promising and stable option for discovering novel compounds from sponges [152] while conserving the natural sponge population [153].…”