Anti-inflammatory, Antioxidant Activities and Safety of Coffea arabica Leaf Extract for Alternative Cosmetic Ingredient

Coffee (Coffea arabica) or Arabica is grown as an economic cash crop in the northern highlands of Thailand. Utilization of coffee leaves has historically been overshadowed by coffee bean products. Phytochemical constituents, antioxidant and anti-inflammatory activities as well as irritation of Thai arabica coffee leaf extract were evaluated. The leaf extract demonstrated potential antioxidant activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, 2,2'-azino-bis (3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical scavenging, and lipid peroxidation inhibition assays, with high phenolic content and flavonoid content. Anti-inflammatory potential was observed in dose-dependent manner by reducing interleukin-6 (IL-6) secretion from LPS-stimulated macrophages. Irritation on the chorioallantoic membrane of hen's eggs were not observed. Therefore, coffee leaf extract has potential as the new alternative ingredient for cosmetics or cosmeceutical products. Moreover, this research has benefit for adding the value to the coffee leaves in off-season for coffee beans.