Bacteriostasis and Anti-Inflammation of Staphylococcus epidermidis Fermentation Broth to Propionibacterium acnes

In this work, Staphylococcus epidermidis (S. epidermidis) fermentation broth with inhibitory effects on the growth of Propionibacterium acnes (P. acnes) and inflammation caused by P. acnes. was obtained. Three kinds of S. epidermidis fermentation broth, cultivated in beef protein medium, and glycerol or glucose added into the beef protein medium, referred to as SFB, Gly-SFB, and Glu-SFB, had different performances on bacteriostasis and anti-inflammation. Upon adding SFB, Gly-SFB or Glu-SFB to the P. acnes culture medium at a concentration of 10%, the CFUs of P. acnes decreased by 44. 6%, 85.9%, and 82.1%, respectively. As the concentration of the fermentation broth increased, the CFUs lowered accordingly. Thermal inactivation of P. acnes (TI.P) induces RAW264.7 cells to produce inflammatory factors and leads to inflammation. Following intervention with Gly-SFB and Glu-SFB, the pro-inflammatory cytokine IL-1 β expression levels diminished by 51.3% and 24.5%, respectively, while the expression levels of IL-6 decreased by 75.4% and 66.7%, respectively. Conversely, after treatment with SFB, the expression level of IL-1 β escalated by 88.7%, whereas the expression level of IL-6 decreased by 19.3%. Western blot revealed that the S. epidermidis fermentation broth exhibits anti-inflammatory activities by inhibiting the production of inflammation-related proteins in the NF-κB signaling pathway. LC-MS/MS integrated with untargeted metabolomics was employed to examine the metabolic variations among SFB, Gly-SFB, and Glu-SFB. Six oligopeptides exhibited elevated concentrations in Gly-SFB and Glu-SFB compared to SFB. The anti-inflammatory efficacy of these six oligopeptides was assessed, and only three oligopeptides, EQIW, HGYK, and WFYL, significantly diminished the expression of pro-inflammatory factors IL-1β and IL-6 induced by TI.P. Therefore, Gly-SFB and Glu-SFB enhance the inhibitory effect on the proliferation of P. acnes and exhibit significant anti-inflammatory properties against TI.P-induced inflammation.