Microbial composition of Korean kefir and antimicrobial activity of Acetobacter fabarum DH1801

Abstract

Kefir is a probiotic dairy product containing multiple species of lactic acid bacteria, acetic acid bacteria, and yeast, with varying microbial composition depending on geographical origin. In the present study, we characterized the acetic acid bacterial population in Korean kefir by next-generation sequencing-based community analysis and isolated a novel acetic acid bacterial strain, Acetobacter fabarum DH1801. To evaluate its potential application in the food industry, the antimicrobial activity of A. fabarum DH1801 against seven foodborne pathogens (Bacillus cereus, Staphylococcus aureus, Listeria monocytogenes, Cronobacter sakazakii, Salmonella Enteritidis, enterotoxigenic Escherichia coli, and Shigella flexneri) was analyzed by growth curve analysis. Remarkably, the culture filtrate of the novel isolate inhibited the growth of all seven pathogenic bacteria in a dose-dependent manner, which was superior to acetic acid solution of same pH value. Our findings suggest that the A. fabarum DH1801 strain forms a protective barrier during kefir fermentation against contamination by foodborne pathogens.

Bioactive Compounds from Kefir and Their Potential Benefits on Health: A Systematic Review and Meta‐Analysis

“…Some yeast strains, such as Saccharomyces cerevisiae KU200284, present double importance: a starter culture and a probiotic [ 44 ]. In Korean kefir, the acetic acid bacterial strain Acetobacter fabarum DH1801 had viability as a functional starter with food preservative mechanisms and the potential as a probiotic agent [ 45 ]. In addition, the species of LAB has a fundamental role in the formation of exopolysaccharide (EPS), which is a significant bioactive compound in kefir [ 37 ].…”

Investigation of bacterial and fungal communities in indoor and outdoor air of elementary school classrooms by 16S rRNA gene and ITS region sequencing

“…The samples that did not meet minimum cDNA concentration (10 ng/μL) were excluded from the 16S rRNA gene and ITS region sequencing (Table S1). ITS3‐ITS4 region of fungal DNA 25 and 16S V3‐V4 region of bacterial DNA 26 were used for gene amplification with the primer sequences shown in Table 1. The amplification step was performed to add multiplexing indices and Illumina sequencing adapters.…”

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

“…Grains, China CD Ropy colonies [21] Grains, China CI - [45] Grains and beverages, Brazil CI - [47] Grains and beverages, Ireland CI - [31] Grains and beverages, Turkey CD, CI Not detected [29] Grains, Turkey CI - [55] Grains, Brazil CI - [46] Grains, Slovenia CD, CI 40 [48] Grains, Argentina CD, CI 11 [27] Grains, Turkey CI - [51] Grains, China CD, CI 11 [44] Grains, Italy CD, CI - [23] Grains, Korea CI - [37] Grains, Belgium CI - [50] Grains, Brazil CD, CI 5 [22] Grains, USA CI - [56] Grains, Russia CD, CI Not detected [30] Grains and beverages, Ireland, France, United Kingdom CI - [34] Grains, Malaysia CI - [57] Grains, Turkey CI - [35] Grains, China CD, CI 18 [28] Kefir and beverages, China CI - [58] Beverages, Korea CI - [59] Grains, China CI - [60] Grains, Turkey CD 3 [61] Grains, Greece CI - [62] Beverage, Korea CI - [63] Grains and beverages, Germany, Italy CI - [38] Grains and beverages, United Kingdom, Caucuses region, Ireland, Lithuania, South Korea, USA CI - [64] Grains, China, Germany, USA CI - [65] Grains, China CD, CI 1 [66] CD: culture-dependent method; CI: culture-independent method; -: isolation not performed.…”