The strong bactericidal properties of
lauric acid (C12:0), a middle chain-
free fatty acid commonly found in natural products, have been shown in a number of studies. However, it has not been demonstrated whether
lauric acid can be used for
acne treatment as a natural
antibiotic against Propionibacterium acnes (P. acnes), which promotes follicular
inflammation (inflammatory
acne). This study evaluated the antimicrobial property of
lauric acid against P. acnes both in vitro and in vivo. Incubation of the skin bacteria P. acnes, Staphylococcus aureus (S. aureus), and Staphylococcus epidermidis (S. epidermidis) with
lauric acid yielded minimal inhibitory concentration (MIC) values against the bacterial growth over 15 times lower than those of
benzoyl peroxide (BPO). The lower MIC values of
lauric acid indicate stronger antimicrobial properties than that of BPO. The detected values of half maximal effective concentration (EC(50)) of
lauric acid on P. acnes, S. aureus, and S. epidermidis growth indicate that P. acnes is the most sensitive to
lauric acid among these bacteria. In addition,
lauric acid did not induce cytotoxicity to human sebocytes. Notably, both
intradermal injection and epicutaneous application of
lauric acid effectively decreased the number of P. acnes colonized with mouse ears, thereby relieving P. acnes-induced ear swelling and granulomatous
inflammation. The obtained data highlight the potential of using
lauric acid as an alternative treatment for
antibiotic therapy of
acne vulgaris.