Journal: Scientific Reports

Article Title: An animal derivative-free medium enhances Lactobacillus johnsonii LJO02 supernatant selective efficacy against the methicillin (oxacillin)-resistant Staphylococcus aureus virulence through key-metabolites

doi: 10.1038/s41598-022-12718-z

Figure Lengend Snippet: Bacterial strain growth curves . ( a ) S. aureus growth curves in LB, MRS, and TIL. ( b ) LR06 and LJO02 growth curves in MRS and TIL. Data are expressed as mean ± SD. All the experiments (n = 3) were repeated 3 times on different days. OD = optical density.

Article Snippet: We compared the activity of Lacticaseibacillus rhamnosus LR06 (DSM 21981) and Lactobacillus johnsonii LJO02 (DSM 33828) cell-free supernatants (CFSs) produced in the conventional animal derivative-based MRS medium and an innovative animal derivative-free broth (TIL) versus the MDR S. aureus (ATCC 43300).

Techniques:

Journal: Scientific Reports

Article Title: An animal derivative-free medium enhances Lactobacillus johnsonii LJO02 supernatant selective efficacy against the methicillin (oxacillin)-resistant Staphylococcus aureus virulence through key-metabolites

doi: 10.1038/s41598-022-12718-z

Figure Lengend Snippet: pH measurement of culture media and CFSs used in the study.

Article Snippet: We compared the activity of Lacticaseibacillus rhamnosus LR06 (DSM 21981) and Lactobacillus johnsonii LJO02 (DSM 33828) cell-free supernatants (CFSs) produced in the conventional animal derivative-based MRS medium and an innovative animal derivative-free broth (TIL) versus the MDR S. aureus (ATCC 43300).

Techniques: Cell Culture

Journal: Scientific Reports

Article Title: An animal derivative-free medium enhances Lactobacillus johnsonii LJO02 supernatant selective efficacy against the methicillin (oxacillin)-resistant Staphylococcus aureus virulence through key-metabolites

doi: 10.1038/s41598-022-12718-z

Figure Lengend Snippet: Evaluation of the effect of single and mixed CFSs produced in MRS and TIL on S. aureus growth and biofilm formation . S. aureus planktonic cells and biofilm OD 600 after 24, 48, and 72 h of treatment with CFSs from LR06, LJO02 and their combination (MIX condition) produced in ( a ) MRS and ( b ) TIL (considering T 0 = 100% strain viability in each experimental condition). OD = optical density. CFSs = cell-free supernatants. ( c ) Planktonic cell and ( d ) biofilm S. aureus viability assessment after 24, 48, and 72 h of treatment with CFSs from LR06, LJO02, and MIX conditions. Data are expressed as mean ± SD of 3 independent experiments (n = 4). All tested conditions significantly reduced both S. aureus planktonic cells and biofilm formation compared to the growth control in LB ( p < 0.0001). Two-way ANOVA was applied with Tukey’s comparison test. * p < 0.05, ** p < 0.01, **** p < 0.0001. RFU = relative fluorescence units. ( e ) CV-reading at 570 nm of S. aureus biofilm at the 3 tested time points. ( f ) Representative 2D and 3D images of CV-stained S. aureus biofilm after 72 h of treatment with the CFSs produced in MRS (top) and TIL (bottom). 2D pictures magnification: 460 X. Scale bar: 100 μm.

Article Snippet: We compared the activity of Lacticaseibacillus rhamnosus LR06 (DSM 21981) and Lactobacillus johnsonii LJO02 (DSM 33828) cell-free supernatants (CFSs) produced in the conventional animal derivative-based MRS medium and an innovative animal derivative-free broth (TIL) versus the MDR S. aureus (ATCC 43300).

Techniques: Produced, Control, Comparison, Fluorescence, Staining

Journal: Scientific Reports

Article Title: An animal derivative-free medium enhances Lactobacillus johnsonii LJO02 supernatant selective efficacy against the methicillin (oxacillin)-resistant Staphylococcus aureus virulence through key-metabolites

doi: 10.1038/s41598-022-12718-z

Figure Lengend Snippet: Evaluation of the effect of modified CFSs from LJO02 produced in TIL on S. aureus growth and biofilm formation. ( a ) S. aureus planktonic cell and biofilm OD 600 after 24, 48, and 72 h of incubation with the CFSs from LJO02 in TIL at pH 6.6 or enzymatically-digested (considering T 0 = 100% viability in each experimental condition). OD = optical density. CFS = cell-free supernatant. TRY = trypsin; PK = proteinase K; PE = pepsin. ( b ) Planktonic cell and ( c ) biofilm S. aureus viability assessment after 24, 48, and 72 h of incubation with modified CFSs. Data are expressed as mean ± SD of 3 independent experiments (n = 4). Trypsin and proteinase K-treated CFSs significantly reduce the planktonic cell viability compared to basification and pepsin treatment, similarly to what occurs with the untreated CFS ( p < 0.0001). Biofilm viability is significantly reduced by trypsin and proteinase K-treated CFSs with respect to basification and pepsin at all tested times ( p < 0.0001), but undigested CFS still shows the best performance ( p < 0.0001 at 24 and 48 h, and p < 0.01 at 72 h with respect to trypsin and proteinase K-digested CFS). Two-way ANOVA was applied with Tukey’s comparison test. ** p < 0.01, **** p < 0.0001. RFU = relative fluorescence units. ( d ) CV-reading at 570 nm of S. aureus biofilm at the 3 tested time points. ( e ) Representative 2D and 3D images of CV-stained S. aureus biofilm after 72 h of treatment with the modified CFSs. 2D pictures magnification: 460 X. Scale bar: 100 μm.

Article Snippet: We compared the activity of Lacticaseibacillus rhamnosus LR06 (DSM 21981) and Lactobacillus johnsonii LJO02 (DSM 33828) cell-free supernatants (CFSs) produced in the conventional animal derivative-based MRS medium and an innovative animal derivative-free broth (TIL) versus the MDR S. aureus (ATCC 43300).

Techniques: Modification, Produced, Incubation, Comparison, Fluorescence, Staining

Journal: Scientific Reports

Article Title: An animal derivative-free medium enhances Lactobacillus johnsonii LJO02 supernatant selective efficacy against the methicillin (oxacillin)-resistant Staphylococcus aureus virulence through key-metabolites

doi: 10.1038/s41598-022-12718-z

Figure Lengend Snippet: Quantification of SCFAs and characterization of protein content in CFSs from LR06 and LJO02 cultured in MRS and TIL for 8 h . ( a – g ) SCFAs amount in CFSs from LR06 and LJO02 produced in MRS and TIL. An unpaired t-test was applied. ( h ) Proteins identified in both MRS and TIL broths, and CFSs from LR06 and LJO02 cultured in both media.

Article Snippet: We compared the activity of Lacticaseibacillus rhamnosus LR06 (DSM 21981) and Lactobacillus johnsonii LJO02 (DSM 33828) cell-free supernatants (CFSs) produced in the conventional animal derivative-based MRS medium and an innovative animal derivative-free broth (TIL) versus the MDR S. aureus (ATCC 43300).

Techniques: Cell Culture, Produced