Lactobacillus kefiranofaciens: From Isolation and Taxonomy to Probiotic Properties and Applications

Abstract

One of the main lactic acid bacterial species found in the kefir grain ecosystem worldwide is Lactobacillus kefiranofaciens, exhibiting strong auto-aggregation capacity and, therefore, being involved in the mechanism of grain formation. Its occurrence and dominance in kefir grains of various types of milk and geographical origins have been verified by culture-dependent and independent approaches using multiple growth media and regions of the 16S rRNA gene, respectively, highlighting the importance of their combination for its taxonomic identification. L. kefiranofaciens comprises two subspecies, namely kefiranofaciens and kefirgranum, but only the first one is responsible for the production of kefiran, the water-soluble polysaccharide, which is a basic component of the kefir grain and famous for its technological as well as health-promoting properties. L. kefiranofaciens, although very demanding concerning its growth conditions, can be involved in mechanisms affecting intestinal health, immunomodulation, control of blood lipid levels, hypertension, antimicrobial action, and protection against diabetes and tumors. These valuable bio-functional properties place it among the most exquisite candidates for probiotic use as a starter culture in the production of health-beneficial dairy foods, such as the kefir beverage.

Enhanced probiotic potential of Lactobacillus kefiranofaciens OSU-BDGOA1 through co-culture with Kluyveromyces marxianus bdgo-ym6

“…Genome mining of L. kefiranofaciens OSU-BDGOA1 for genes associated with bacteriocin production revealed the presence of genes that encode class III bacteriocins; Enterolysin- A, a cell wall degrading bacteriocin with broad spectrum activity against Gram-positive and Gram-negative bacteria ( Nilsen et al, 2003 ) and helveticin J, a bacteriocin with a narrow antibacterial spectrum against Gram-positive bacteria including Listeria monocytogenes ( Joerger and Klaenhammer, 1986 ), and that has been previously found in other L. kefiranofaciens strains ( Xing et al, 2017 ; Georgalaki et al, 2021 ). However, we cannot directly attribute the observed in vitro antibacterial activity to the bacteriocins mined from the genome.…”

Analysis of the milk kefir pan-metagenome reveals four community types, core species, and associated metabolic pathways

“… 2 Previous research efforts have verified the presence and dominance of kefiran producing bacteria, such as Lactobacillus kefiranofaciens and Lentilactobacillus kefiri within the milk kefir grain microbiome. 3 This pattern of dominance has been verified through the microbial analysis of kefir grains from different geographic regions, with heterogeneity typically arising from low-abundance bacterial and eukaryotic communities. 4 , 5 In contrast, the resulting fermented milk known as ‘milk kefir’ has been reported to have a more varied compositional profile compared to the grain 2 and can undergo substantial compositional changes within a few hours.…”

Analysis of the Milk Kefir Pan-Metagenome Reveals Four Community Types, Core Species and Associated Metabolic Pathways

“…2 Previous research efforts have verified the presence and dominance of kefiran producing bacteria, such as Lactobacillus kefiranofaciens and Lentilactobacillus kefiri within the milk kefir grain microbiome. 3 This pattern of dominance has been verified through the microbial analysis of kefir grains from different geographic regions, with heterogeneity typically arising from low-abundance bacterial and eukaryotic communities. 4,5 In contrast, the resulting fermented milk known as 'milk kefir' has been reported to have a more varied compositional profile compared to the grain 2 and can undergo substantial compositional changes within a few hours.…”