Exopolysaccharides evaluation

Wolter, A., Hager, A.-S., Zannini, E., Galle, S. et oL (2014) Evaluation of exopolysaccharide producing Weissella cibaria MGl strain for the production of sourdough from various flours. Food MicrobioL, 37, 44-50. 

Before microbial exopolysaccharides can be used in foodstuffs tfiey must be evaluated against an industrial standard to ensure that product quality is maintained or improved. The tight deadlines imposed on industry mean that product evaluation must be effective and logical to ensure a rapid result. Therefore, dear objectives and criteria are set against which new products are tested. 

Some studies have evaluated the effects of polysaccharides in some physiological responses. Lindstrom et al. studied the effect of four polysaccharides, namely sclero-glucan (fungal exopolysaccharide), xanthan gum, gellan, and native dextran on plasma lipids and caecal formation of short-chain fatty acids (SCFA) in mice. Results showed... 

IFN-a production, while IL-18 production was not increased. Moreover, EPS-1, at a concentration of 100 microg/mL, induced the production of IL-12 at considerable levels IFN-y and TNF-a were also detected. The immunomodulatory activity of EPS was correlated to evaluation of its antiviral effect [55]. A similar study was published later in a paper by Arena et at, in which the immunomodulatory and antiviral effects of an exopolysaccharide EPS-2, isolated from a strain of Geobacillus thermodendrifi-cans, were described. EPS-2 also stimulated the cytokine production in PBMC cells in a concentration-dependent manner, like EPS-1. A high level of IL-12, IFN-y, TNF-a and IL-18 was revealed after EPS-2 treatment [56]. 

From the marine bacterium Pseudoalteromonas sp. AM, an exopolysaccharide (EPS) was isolated which exhibited significant antiviral activity towards Herpes simplex (HSV-I). The effect resulted in the inhibition of virus replication of 60% when HSV-I was treated with 10% of EPS [81]. A similar result was reported in a previous paper of Matsuda et al. They described the antiviral effect, evaluated in RPMI8226 cells infected with HS V-1 virus, of a sulfated polysaccharide produced by a marine Pseudomonas species WAK-1 strain [82]. 

Conventional wisdom has held that dispersants act as biopenetrants to open the biofilms and allow penetration of the exopolysaccharides by biocides. Claims have been made that the dispersants act to allow penetration of the biocides into the cell or that the dispersants trigger biofilm sloughing. At best the mode of action of these dispersants is poorly understood. Among the difficulties of work with non-toxic agents is the lack of measurement systems. Evaluation of biocides is done by measuring kill or inhibition. With non-toxic materials, alternative methods of assessing chemical efficacy must be developed. 

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