The effect of various antibiotics on the hydrolytic activity of partially purified lipases from Corynebacterium acnes on tributyrin was studied by continuous potentiometric titration and by agar diffusion assays. Tetracycline hydrochloride, chlortetracycline hydrochloride, and demeclocycline hydrochloride inhibited C acnes lipase activity by 70% to 80% at concentrations of 500 μg/ml of substrate. Penicillin G potassium, erythromycin, neomycin sulfate, and streptomycin sulfate had no inhibitory effect on C acnes lipase activity.
However, the minimum concentration of tetracyclines which produced detectable lipase inhibition in vitro was higher than the concentrations of tetracyclines found in skin during the usual regimen of tetracycline therapy in acne vulgaris, and much higher than the minimum bacteriostatic levels of tetracyclines used on C acnes in vitro.
Puhvel SM, Reisner RM. Effect of Antibiotics on the Lipases of Corynebacterium acnes in Vitro. Arch Dermatol. 1972;106(1):45-49. doi:10.1001/archderm.1972.01620100033009