Synbiosis between Enterococcus faecium DSM ۳۵۳۰ and Fructan Compounds of Different Degree of Polymerization: a Preliminary In vitro Assay in a Condition Simulated Chicken Caecum

This experiment was conducted to determine the potential synergistic relationship between Enterococcus faecium and fructans with different average Degree of Polymerization (DPav) including OligoFructose (OF, DPav ۴), Standard-inulin (ST-inulin, DPav ۱۰), Synergy۱-Inulin (SYN۱-inulin, DPav ۱۵) and High-Polymer inulin (HP-inulin, DPav ۲۵). A sterilized minimal MRS broth media was prepared by omission of glucose. The media pH was adjusted to a constant initial value of ۵.۸±۰.۱ and the temperature was maintained at ۴۱°C. Sterilized fructans were added (۱% wt⁄vol) to the broths, as experimental treatments with ۳ replications each, and the medium with no added prebiotic was considered as the control. The same starting density of ۱۰۸ E. faecium cells per ml was introduced to all media. The media pH, viable cells count, as well as growth of the latter were determined during ۲۴ hours of incubation. The lowest pH and best growth rates were observed in the media enriched with OF and ST-inulin. Unlike aerobic, the anaerobic conditions produced no significant differences in growth of the bacteria among SYN۱-inulin and HP-inulin treatments compared to the control. The viable cells count in the media containing OF was significantly higher than in the control and other treatments. The significant differences were also found among the control and treatments supplemented with ST-inulin and SYN۱-inulin. In conclusion, the fructans with lower DP were preferentially metabolized by E. faecium, and hence it follows that a synbiotic blend of E. faecium and OF has the potential to be used in poultry nutrition.