Isolation and in-vitro probiotic characterization of fructophilic lactic acid bacteria from Chinese fruits and flowers

Abstract

This study was undertaken to focus on the isolation and probiotic characterization of fructophilic lactic acid bacteria (FLAB) isolated from various flowers and fruits belonging to China. Seventy-three FLAB isolates exhibiting fructose fermentation were grown in 30% fructose media, and only eight isolates showed the capability to grow under such high osmotic pressure. From the above isolates, 16S rRNA gene sequencing revealed two strains as Fructobacillus fructosus, three strains as Lactobacillus kunkeei, two strains as F. pseudoficulneus, and one strain as F. durionis. These strains were characterized subsequently for their carbohydrate metabolism and probiotic potential. In comparison to other isolated FLAB strains, L. kunkeei strains showed the maximum capacity to tolerate various low pH levels and bile acid concentrations together with maximal effects on cholesterol assimilation, antipathogenic activity, and hydrophobicity. The fructophilic strains preferred d-fructose over d-glucose and so these strains have potential for use in cereal fermentation to ameliorate fructose-mediated irritable bowel syndromes.