broth microdilution assay against e coli atcc 25922 ec  (ATCC)

Journal: BMC Microbiology

Article Title: Inhibitory efficacy, production dynamics, and characterization of postbiotics of lactic acid bacteria

doi: 10.1186/s12866-025-04123-z

Figure Lengend Snippet: Inhibition zone of untreated cell-free supernatants from LAB strains incubated for 16 and 24 h. The substances'antimicrobial activity was determined when they were exposed to pathogens of E. coli ATCC 25922 ( a ), Staph. aureus ATCC 43300 ( b ), Salm. Typhimurium ATCC 14028 ( c ), Sh. sonnei ATCC 25931 ( d ), Ps. aeruginosa ATCC 10145 ( e ), and B. cereus ATCC 14579 ( f ). The error bars indicate the standard error of the mean ( n = 3). CFS, Cell-free supernatant. a - c Represents statistically significant differences among different CFS of LAB strains exposed to respective pathogens tested for 16 h ( n = 3, p < 0.05, Duncan’s test). x – z Represents statistically significant differences among different CFS of LAB strains exposed to respective pathogens tested for 24 h. ( n = 3, p < 0.05, Duncan’s test). LP, CFS obtained from L. plantarum NBRC 3070; LA, CFS obtained from L. acidophilus ATCC 4356; LC, CFS obtained from L. casei ATCC 393; LGG, CFS obtained from L. rhamnosus GG ATCC 53103, and BAL, CFS obtained from B. animalis subsp . lactis ATCC 27673

Article Snippet: The nCFSs were treated with ( a ) trypsin, ( b ) pepsin, and ( c ) papain in broth microdilution assay against E. coli ATCC 25922 (EC), Salm.

Techniques: Inhibition, Incubation, Activity Assay

Journal: BMC Microbiology

Article Title: Inhibitory efficacy, production dynamics, and characterization of postbiotics of lactic acid bacteria

doi: 10.1186/s12866-025-04123-z

Figure Lengend Snippet: Effect of OD value and pH changes on the postbiotics activity of LAB strains. The LAB strains were incubated for 48 h at 37 °C, and the inhibitory activity of these postbiotics against E. coli ATCC 25922 was influenced by ( a ) cell density (OD value), ( b ) pH values, and ( c ) OD and pH values. The bar graphs represent the antimicrobial activity of postbiotics, and the line graphs represent OD and pH values, respectively. OD values and optical density are measured at OD 600nm . LP: OD and pH values from L. plantarum NBRC 3070; LA: OD and pH values from L. acidophilus ATCC 4356; LC: OD and pH values from L. casei ATCC 393; LGG: OD and pH values from L. rhamnosus GG ATCC 53103

Article Snippet: The nCFSs were treated with ( a ) trypsin, ( b ) pepsin, and ( c ) papain in broth microdilution assay against E. coli ATCC 25922 (EC), Salm.

Techniques: Activity Assay, Incubation

Journal: BMC Microbiology

Article Title: Inhibitory efficacy, production dynamics, and characterization of postbiotics of lactic acid bacteria

doi: 10.1186/s12866-025-04123-z

Figure Lengend Snippet: Inhibitory activity (%) obtained from neutralized cell-free supernatants (nCFS) of four LAB strains. The nCFSs were treated with ( a ) trypsin, ( b ) pepsin, and ( c ) papain in broth microdilution assay against E. coli ATCC 25922 (EC), Salm. Typhimurium ATCC 14028 (ST), Staph. aureus ATCC 43300 (SA), and Ps. aeruginosa ATCC 10145 (PA) for 24 h aerobically. The inhibition activity of enzyme-treated nCFS against pathogenic bacteria strains was compared with positive control (100% activity of CFS) cultures with three replications. The error bars indicate the standard error of the mean ( n = 3). a and b Represent statistically significant differences within each indicator strain among the BLIS of the LAB strain ( n = 3, p < 0.05, Duncan’s test)

Article Snippet: The nCFSs were treated with ( a ) trypsin, ( b ) pepsin, and ( c ) papain in broth microdilution assay against E. coli ATCC 25922 (EC), Salm.

Techniques: Activity Assay, Microdilution Assay, Inhibition, Bacteria, Positive Control

Journal: BMC Microbiology

Article Title: Inhibitory efficacy, production dynamics, and characterization of postbiotics of lactic acid bacteria

doi: 10.1186/s12866-025-04123-z

Figure Lengend Snippet: Inhibition zone of untreated cell-free supernatants from LAB strains incubated for 16 and 24 h. The substances'antimicrobial activity was determined when they were exposed to pathogens of E. coli ATCC 25922 ( a ), Staph. aureus ATCC 43300 ( b ), Salm. Typhimurium ATCC 14028 ( c ), Sh. sonnei ATCC 25931 ( d ), Ps. aeruginosa ATCC 10145 ( e ), and B. cereus ATCC 14579 ( f ). The error bars indicate the standard error of the mean ( n = 3). CFS, Cell-free supernatant. a - c Represents statistically significant differences among different CFS of LAB strains exposed to respective pathogens tested for 16 h ( n = 3, p < 0.05, Duncan’s test). x – z Represents statistically significant differences among different CFS of LAB strains exposed to respective pathogens tested for 24 h. ( n = 3, p < 0.05, Duncan’s test). LP, CFS obtained from L. plantarum NBRC 3070; LA, CFS obtained from L. acidophilus ATCC 4356; LC, CFS obtained from L. casei ATCC 393; LGG, CFS obtained from L. rhamnosus GG ATCC 53103, and BAL, CFS obtained from B. animalis subsp . lactis ATCC 27673

Article Snippet: Enzymes (Bendosen, Norway) were incubated with nCFS at 37 °C for 4 h, then inactivated by heating at 100 °C for 5 min. Antibacterial activity was assessed via broth microdilution against E. coli ATCC 25922, Salm.

Techniques: Inhibition, Incubation, Activity Assay

Journal: BMC Microbiology

Article Title: Inhibitory efficacy, production dynamics, and characterization of postbiotics of lactic acid bacteria

doi: 10.1186/s12866-025-04123-z

Figure Lengend Snippet: Effect of OD value and pH changes on the postbiotics activity of LAB strains. The LAB strains were incubated for 48 h at 37 °C, and the inhibitory activity of these postbiotics against E. coli ATCC 25922 was influenced by ( a ) cell density (OD value), ( b ) pH values, and ( c ) OD and pH values. The bar graphs represent the antimicrobial activity of postbiotics, and the line graphs represent OD and pH values, respectively. OD values and optical density are measured at OD 600nm . LP: OD and pH values from L. plantarum NBRC 3070; LA: OD and pH values from L. acidophilus ATCC 4356; LC: OD and pH values from L. casei ATCC 393; LGG: OD and pH values from L. rhamnosus GG ATCC 53103

Article Snippet: Enzymes (Bendosen, Norway) were incubated with nCFS at 37 °C for 4 h, then inactivated by heating at 100 °C for 5 min. Antibacterial activity was assessed via broth microdilution against E. coli ATCC 25922, Salm.

Techniques: Activity Assay, Incubation

Journal: BMC Microbiology

Article Title: Inhibitory efficacy, production dynamics, and characterization of postbiotics of lactic acid bacteria

doi: 10.1186/s12866-025-04123-z

Figure Lengend Snippet: Inhibitory activity (%) obtained from neutralized cell-free supernatants (nCFS) of four LAB strains. The nCFSs were treated with ( a ) trypsin, ( b ) pepsin, and ( c ) papain in broth microdilution assay against E. coli ATCC 25922 (EC), Salm. Typhimurium ATCC 14028 (ST), Staph. aureus ATCC 43300 (SA), and Ps. aeruginosa ATCC 10145 (PA) for 24 h aerobically. The inhibition activity of enzyme-treated nCFS against pathogenic bacteria strains was compared with positive control (100% activity of CFS) cultures with three replications. The error bars indicate the standard error of the mean ( n = 3). a and b Represent statistically significant differences within each indicator strain among the BLIS of the LAB strain ( n = 3, p < 0.05, Duncan’s test)

Article Snippet: Enzymes (Bendosen, Norway) were incubated with nCFS at 37 °C for 4 h, then inactivated by heating at 100 °C for 5 min. Antibacterial activity was assessed via broth microdilution against E. coli ATCC 25922, Salm.

Techniques: Activity Assay, Microdilution Assay, Inhibition, Bacteria, Positive Control