Bacteriocin from Lacticaseibacillus rhamnosus sp. A5: Isolation, Purification, Characterization, and Antibacterial Evaluation for Sustainable Food Processing

Abstract

A new Lacticaseibacillus rhamnosus strain A5 was isolated from pickle soup and characterized for its probiotic suitability. Strain A5 was Gram-positive, catalase-negative, acid-producing, and exhibited potential antibacterial activity against Escherichia coli (inhibition zone 17.3 mm), Bacillus subtilis (inhibition zone 14.5 mm), Salmonella enterica (zone of inhibition 16.1 mm) and Staphylococcus aureus (zone of inhibition 14.2 mm) by performing investigations on the disc diffusion. The cell-free supernatant of newly isolated strain A5 retained its inhibition ability of the growth of test bacteria at pH 2.0 to 5.0, temperature 121 °C for 30 min and UV irradiation for 8 h. However, the inhibitory effects of cell-free supernatant disappeared when subjected to papain, trypsin, and pepsin enzymatic treatments. By eliminating the interferences of organic acid and hydrogen peroxide, the cell-free supernatant possessed antibacterial activity against two indicator bacteria (E. coli and B. subtilis) and showed high thermal tolerance. These results indicated that the antibacterial substances produced by strain A5 were proteinaceous in nature, namely bacteriocin. The antibacterial bacteriocins in the supernatant of the strain A5 culture were further purified by ammonium sulfate fractionation and gel filtration chromatography. The purified bacteriocins also showed a pronounced inhibitory effect against E. coli and B. subtilis. The approximated molecular weight of bacteriocins was less than 14 kDa after determining by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. In conclusion, the newly isolated strain A5 and its bacteriocins could be potentially applied in food preservation to prevent the risk of foodborne illness.

Antibacterial activity and mechanism of a novel bacteriocin produced by Lactiplantibacillus plantarum against Escherichia coli and Staphylococcus aureus

“…1a. The absorption peaks at 228 nm and 280 nm in the UV spectrum indicated that the crude extracts consisted of proteins and peptides (Liao et al ., 2017; Biter et al ., 2019), which indicated that crude extracts might be bacteriocin (Ren et al ., 2022). A previous study also indicated that bacteriocins were antimicrobial proteins or peptides produced by lactic acid bacteria that had the potential to combat contamination by pathogenic bacteria in food (Garsa et al ., 2014).…”

Antibacterial activity and mechanism of a novel bacteriocin produced by Lactiplantibacillus plantarum against Escherichia coli and Staphylococcus aureus

“…1a. The absorption peaks at 228 nm and 280 nm in the UV spectrum indicated that the crude extracts consisted of proteins and peptides (Liao et al ., 2017; Biter et al ., 2019), which indicated that crude extracts might be bacteriocin (Ren et al ., 2022). A previous study also indicated that bacteriocins were antimicrobial proteins or peptides produced by lactic acid bacteria that had the potential to combat contamination by pathogenic bacteria in food (Garsa et al ., 2014).…”

Synthesis of Silver–Calcium Phosphate Visible Light Responsive Photocatalytic Materials and Their Antibacterial Properties

“…E. coli (Dh5α) was used to evaluate the antibacterial activity of the prepared samples [ 26 , 27 ]. 25 μL of LB broth medium containing E. coli was applied to an agar plate, and 30 mg of the pelleted sample was placed on the plate at equal intervals and incubated for 24 h under dark conditions.…”

Identification, Safety Assessment, and Antimicrobial Characteristics of Cocci Lactic Acid Bacteria Isolated from Traditional Egyptian Dairy Products

“…The inhibitory activity of the hydrogen peroxide was lessened with the application of catalase (1 mg/mL) (Sigma, St. Louis, MO, USA). The samples were heated to 100 °C for ten minutes in order to decrease enzyme activity [ 25 ].…”

Antibacterial activity and mechanism of a novel bacteriocin produced by Lactiplantibacillus plantarum against Escherichia coli and Staphylococcus aureus

“…1a. The absorption peaks at 228 nm and 280 nm in the UV spectrum indicated that the crude extracts consisted of proteins and peptides (Liao et al ., 2017; Biter et al ., 2019), which indicated that crude extracts might be bacteriocin (Ren et al ., 2022). A previous study also indicated that bacteriocins were antimicrobial proteins or peptides produced by lactic acid bacteria that had the potential to combat contamination by pathogenic bacteria in food (Garsa et al ., 2014).…”

Synthesis of Silver–Calcium Phosphate Visible Light Responsive Photocatalytic Materials and Their Antibacterial Properties

“…E. coli (Dh5α) was used to evaluate the antibacterial activity of the prepared samples [ 26 , 27 ]. 25 μL of LB broth medium containing E. coli was applied to an agar plate, and 30 mg of the pelleted sample was placed on the plate at equal intervals and incubated for 24 h under dark conditions.…”

Identification, Safety Assessment, and Antimicrobial Characteristics of Cocci Lactic Acid Bacteria Isolated from Traditional Egyptian Dairy Products

“…The inhibitory activity of the hydrogen peroxide was lessened with the application of catalase (1 mg/mL) (Sigma, St. Louis, MO, USA). The samples were heated to 100 °C for ten minutes in order to decrease enzyme activity [ 25 ].…”

Antibacterial activity and mechanism of a novel bacteriocin produced by Lactiplantibacillus plantarum against Escherichia coli and Staphylococcus aureus

“…1a. The absorption peaks at 228 nm and 280 nm in the UV spectrum indicated that the crude extracts consisted of proteins and peptides (Liao et al ., 2017; Biter et al ., 2019), which indicated that crude extracts might be bacteriocin (Ren et al ., 2022). A previous study also indicated that bacteriocins were antimicrobial proteins or peptides produced by lactic acid bacteria that had the potential to combat contamination by pathogenic bacteria in food (Garsa et al ., 2014).…”

Synthesis of Silver–Calcium Phosphate Visible Light Responsive Photocatalytic Materials and Their Antibacterial Properties

“…E. coli (Dh5α) was used to evaluate the antibacterial activity of the prepared samples [ 26 , 27 ]. 25 μL of LB broth medium containing E. coli was applied to an agar plate, and 30 mg of the pelleted sample was placed on the plate at equal intervals and incubated for 24 h under dark conditions.…”

Identification, Safety Assessment, and Antimicrobial Characteristics of Cocci Lactic Acid Bacteria Isolated from Traditional Egyptian Dairy Products

“…The inhibitory activity of the hydrogen peroxide was lessened with the application of catalase (1 mg/mL) (Sigma, St. Louis, MO, USA). The samples were heated to 100 °C for ten minutes in order to decrease enzyme activity [ 25 ].…”