## Materials and Methods
### Isolation of LAB and Bifidobacterium  
In order to investigate the LAB in the stored samples of honeycombs filled with oregano honey, 100 g of each honeycomb was weighed, placed in a sterile Stomacher blender bag under completely sterile conditions and homogenized for 2 min using a Stomacher 400 Circulator. Then, 900 mL of peptone saline diluent were added to give a total volume of 1 L (0.9% _w/v_ NaCl, 0.1% _w/v_ Tween 80 and 0.1% _w/v_ peptone). The above homogenization technique was repeated for 2 min [39] and 10-fold serial dilutions were prepared in normal saline diluents. Aliquots of 0.1 mL of each 10-fold serial dilution were spread on modified MRS agar (Oxoid) adjusted to an agar content of 1.5% _w/v_ (Agar, Merck) and supplemented with 0.3% _w/v_ CaCO\({}_{3}\) (Merck) [40]. The plates for the recovery of facultative and strict anaerobic LAB and _Bifidobacterium_ were incubated for 3-4 days at 37 \({}^{\circ}\)C under anaerobic conditions using anaerobic jars with Anaerobic# A gas packs (Merck) [41]. Following incubation, colonies from the modified MRS agar of a different morphology with a surrounding clear zone in the agar, indicating acid production, were transferred to the MRS agar without CaCO\({}_{3}\) to grow pure cultures under conditions as described above. In a general approach, cultures were identified as LAB species or _Bifidobacterium_ by evaluating their morphological, cultural, physiological and biochemical characteristics by the procedures described in [PERSON]'s Manual of Systematic Bacterology. At least 10 selected isolates from each plate were initially identified based on the following: microscopic examination of Gram-stained cells, motility, catalase and oxidase reactions, gas production from glucose and growth in anaerobic conditions. Finally, phenotypic observations and biochemical tests were performed using the VITEK2 Compact System [42; 43]. The presumptive LAB isolates were further characterized according to their registered protein and peptide information analysis results with the help of the Microflex LT MALDI-TOF MS (matrix-assisted laser desorption ionization time-of-flight mass spectrometry) (Bruker Daltonics, Bremen, Germany), which is a new technology for identifying LAB cultures. Mass spectra were processed using BioTyper software (version 3.0; Bruker Daltonics) running with the BioTyper database (version DB-5989). Matching between experimental MALDI-TOF MS profiles obtained from bacteria isolates and the reference MALDI-TOF MS profiles was expressed by BioTyper according to a Log(Score). Analyses were conducted in accordance with the manufacturer's instructions and performed twice for each isolate. Results (BioTyper score value, created by an automatic mass spectra comparison with the Bruker library) with a score value \(>\)2.3 were interpreted as identified at the species level with a high probability. A score value between 1.7 and 2.0 implies probability only at the genus level [44; 45]. Determination of the Antibacterial Activity of LAB and Bifidobacterium against the Isolated Pathogens and Spoilage Bacteria  
Preparation of the Cell-Free Supernatant (CFS)  
In short, MRS broth (20 mL) was inoculated separately with the LAB isolates previously characterized and incubated anaerobically at 37 \({}^{\circ}\)C for 72 h. After incubation, a cell-free supernatant was obtained by centrifuging the bacterial culture at 10,000\(\times\)\(g\) for 10 min at 4 \({}^{\circ}\)C, followed by filtration of the supernatant through a 0.22 \(\upmu\)m syringe filter with a low protein binding capacity membrane (cellulose acetate, Rotilabo; syringe filter, [PERSON]). For _Bifidobacterium_ isolates, the procedure was carried out as follows. The strains were inoculated into the MRS broth at 1% (\(\%\)). After 16 h of incubation at 37 \({}^{\circ}\)C, each culture supernatant was collected by centrifugation at 22,100\(\times\)\(g\) for 30 min. The supernatant was sterilized by filtration through 0.45 and 0.22 \(\upmu\)m poresize filters sequentially and precipitated with 70% ammonium sulfate.