Zinc Gluconate

Zinc gluconate is the zinc salt of gluconic acid, and it's the form of zinc with the strongest published evidence for direct antibacterial action against Cutibacterium acnes (formerly Propionibacterium acnes), the bacterium implicated in inflammatory acne. The mechanism: zinc gluconate inhibits bacterial lipase activity (the enzyme C. acnes uses to convert sebum into inflammation-driving free fatty acids) and interferes with bacterial protein synthesis. In oral form, it's been used in dermatology for decades for moderate acne (Rubozinc, Zinc-50). Topically, it shows up in serums and toners from Paula's Choice, La Roche-Posay Effaclar, and several K-beauty acne lines. Distinct from zinc PCA (which is sebum-regulating but not directly antibacterial) and zinc oxide (which is a sunscreen filter and mild surface antibacterial). If you have inflammatory or hormonal acne, zinc gluconate is worth seeking out specifically — it's one of the few non-prescription topicals with antibacterial mechanism of action.