[The effect of natural probiotic inulin to the quantitative microbiological indicators of bifidogenic effect: in vitro research].

INTRODUCTION

The aim of this paper was to examine and to compare microbiological parameters of bifidogenesis as important indicators of bifidogenic effect in infant formulas, with and without inulin supplement as a prebiotic; we also evaluated the rationale for inulin supplementation in order to improve biofidogenesis.

MATERIAL AND METHODS

Feces of healthy, breast-fed infants were used to examine and to isolate the accumulated culture of Bifidobacterium spp. Human milk and infant formulas (with or without inulin supplement) were used to examine the effect of substrate to bifidogenic effect. Pure chicory inulin was used as a natural prebiotic for the supplementation of infant formulas in concentration of 0.4 g and 0.8 g to 100/ml of substrate. In vitro effects of bifidogenesis were observed in all substrates by determining microbiological parameters at the beginning (index 0) and at the end of the experiments, after 48 hours (index 48). We observed and compared two microbiological parameters of bifidogenesis: the total number of bifidobacteria and dry biomass. Phase-contrast microscopy was used to identify Bifidobacterium spp. in accumulated mixed culture. The process of bifidogenesis was controlled by light transmission microscopy in light filed. Total number of Bifidobacterium spp. was determined by the method of serial dilution. Dry biomass was gravimetrically measured. Bifidogenic effect was calculated for each substrate. Dry biomass from the human milk substrate was used as a reference value.

RESULTS

The obtained mean value of bifidogenic effect of standard milk formula was lower for 29% compared to mean value of bifidogenic index of human milk. The mean value of bifidogenic index of infant formula supplemented with 0.4 g and 0.8 g of inulin respectively was statistically significantly higher compared to the mean value of bifidogenic effect of human milk (>38% and >104%, respectively).

CONCLUSION

The rationale for supplementation of infant formulas with inulin was confirmed.