Bifidobacterium aquikefiri sp. nov., isolated from water kefir

Abstract

A novel Bifidobacterium, strain LMG 28769 T , was isolated from a household water kefir fermentation process. Cells were Gram-stain-positive, non-motile, non-spore-forming, catalase-negative, oxidase-negative and facultatively anaerobic short rods. Analysis of its 16S rRNA gene sequence revealed Bifidobacterium crudilactis and Bifidobacterium psychraerophilum (97.4 and 97.1 % similarity towards the respective type strain sequences) as nearest phylogenetic neighbours. Its assignment to the genus Bifidobacterium was confirmed by the presence of fructose 6-phosphate phosphoketolase activity. Analysis of the hsp60 gene sequence revealed very low similarity with nucleotide sequences in the NCBI nucleotide database. The genotypic and phenotypic analyses allowed the differentiation of strain LMG 28769T from all recognized Bifidobacterium species. Strain LMG 28769 T (5CCUG 67145 T 5R 54638 T

The water kefir grain inoculum determines the characteristics of the resulting water kefir fermentation process

“…The novel species B. aquikefiri (Laureys et al . ) was found in water kefirs A and C but not in water kefir B, indicating that it was not necessary for water kefir grain growth neither for the course of the fermentation process.…”

“…Part of the acetate production may be attributed to bifidobacteria, as higher acetate concentrations in water kefirs A and C coincided with their presence (Laureys et al . ). Nevertheless, given the low acetate concentrations in these water kefirs, bifidobacterial metabolism was of minor impact during fermentation.…”

“…Recently, a novel Bifidobacterium species was found in water kefir, but its importance during water kefir fermentation remains unclear (Laureys et al . ). The main metabolites produced during water kefir fermentation are ethanol, lactic acid, glycerol, acetic acid and mannitol; the main aroma compounds are 2‐methyl‐1‐propanol, isoamylalcohol, ethyl acetate, isoamyl acetate, ethyl hexanoate and ethyl octanoate (Laureys and De Vuyst ).…”

“…The LAB species Lactobacillus hilgardii is frequently associated with water kefir fermentation and is thought to be responsible for the water kefir grain growth because of its production of EPS from sucrose (Pidoux 1989;Waldherr et al 2010). Recently, a novel Bifidobacterium species was found in water kefir, but its importance during water kefir fermentation remains unclear (Laureys et al 2016). The main metabolites produced during water kefir fermentation are ethanol, lactic acid, glycerol, acetic acid and mannitol; the main aroma compounds are 2-methyl-1-propanol, isoamylalcohol, ethyl acetate, isoamyl acetate, ethyl hexanoate and ethyl octanoate (Laureys and De Vuyst 2014).…”

Exploring the role of the microbiota member Bifidobacterium in modulating immune-linked diseases

“…Originally isolated from the faeces of breast-fed infants by Tissier in 1899, members of the genus Bifidobacterium are commonly found in the GI tract of mammals. They have also been isolated from birds, social insects such as honey bees [9,10], and more recently from water kefir [11][12][13]. There are currently 55 recognised (sub)species of Bifidobacterium [14].…”