Figure 7: Verification of the implication of SCFAs produced by L. fermentum NCIMB 5221 in suppressing colon cancer cell growth. (a) The anti-proliferative effect of SCFAs doses at similar concentrations than what was produced by probiotic bacteria as described in Figure 6. (b) The inhibitory effect of the SSFs and SFF+LA, formulations corresponding to L. fermentum NCIMB 5221, on the proliferation of colon cancer cells for 72 h, compared to the bacterial conditioned cell culture medium (CM) containing naturally produced probiotic SCFAs. L. acidophilus ATCC 314 and L. rhamnosus ATCC 53103 were used as controls. SSF+LA was prepared with the addition of different concentrations of lactic acid and pure SCFAs to DMEM media (Figure 6). *p < 0.05, **p < 0.01, ***p < 0.001 compared to controls. The data values represent the mean ± SEM (n=6). L. a. 314: L. acidophilus ATCC 314, L. r 701359: L. reuteri NCIMB 701359. SSF: SCFA synthetic formulation. LA: lactic acid.