. 2020 May 19;19:106. doi: 10.1186/s12934-020-01365-6

Table 2.

Comparison of the antimicrobial activity of cell-free supernatants (CFSs) of Lb. plantarum SF9C and Lb. brevis SF9B, separately and combined, before and after the treatment with proteinase K and high temperature heating, against L. monocytogenes ATCC^® 19111™, S. aureus 3048, E. coli 3014 and S. Typhimurium FP1, determined by agar well-diffusion assay and expressed as the diameter of inhibition zones around the wells (cm)

Treatment of CFS	Lactobacillus strains	Diameter of inhibition zone (cm)
Treatment of CFS	Lactobacillus strains	L. monocytogenes ATCC^® 19111™	S. aureus 3048	E. coli 3014	S. Typhimurium FP1
Before treatment	Lb. plantarum SF9C	1.92 ± 0.03^az	1.57 ± 0.06^ay	1.50 ± 0.05^ayw	1.38 ± 0.03^aw
	Lb. brevis SF9B	0.00 ± 0.00^ez	0.00 ± 0.00^ez	0.00 ± 0.00^ez	0.00 ± 0.00^fz
	Combined SF9C + SF9B	1.72 ± 0.03^bz	0.98 ± 0.03^dx	1.13 ± 0.06^cy	1.00 ± 0.00^cx
proteinase K	Lb. plantarum SF9C	1.10 ± 0.00^dy	1.17 ± 0.03^cyz	1.23 ± 0.03^bz	1.20 ± 0.00^bxz
	Lb. brevis SF9B	0.00 ± 0.00^ez	0.00 ± 0.00^ez	0.00 ± 0.00^ez	0.00 ± 0.00^fz
	Combined SF9C + SF9B	1.02 ± 0.03^dz	0.90 ± 0.00^dy	0.98 ± 0.03^dz	0.85 ± 0.00^ey
100 °C/30 min	Lb. plantarum SF9C	1.68 ± 0.03^bz	1.52 ± 0.03^by	1.30 ± 0.00^bx	1.23 ± 0.03^bx
	Lb. brevis SF9B	0.00 ± 0.00^ez	0.00 ± 0.00^ez	0.00 ± 0.00^ez	0.00 ± 0.00^fz
	Combined SF9C + SF9B	1.53 ± 0.06^cz	0.93 ± 0.06^dx	1.03 ± 0.06^cdy	0.92 ± 0.03^dx

^abcdefDifferent letter means statistically significant difference (p < 0.05) within the same column among the treatments of CFSs and used Lactobacillus strains

^wxyzDifferent letter means statistically significant difference (p < 0.05) within the same row among the used pathogens. Statistical analysis was carried out using ANOVA and the results are reported as mean value ± SD of three independent experiments