Tea extracts for inhibition of Propionibacterium acnes

Abstract

Oolong tea is a semi-oxidised Chinese tea obtained from leaves of Camellia sinensis. Although anti-bacterial activities of oolong extract against various bacteria have been reported, there is no evidence on anti-bacterial activity against Propionibacterium acnes (P. acnes), causative bacterium of skin acne. Here, it was found that the extract from oolong tea residue (the leaves that has been used in hot water) contains high amount of epigallocatechin-3-gallate (EGCG), possessed anti-oxidant, anti-inflammation, and anti-P. acnes activity (minimum inhibition concentration of 1.25 mg/ml), and minimal toxicity against mice white blood cells. Combination of this tea extract and mangosteen extract showed enhanced anti-P. acnes activity. Lastly, encapsulation of the extract into alginate bead provided beads with anti-P. acnes activity, even the beads had been kept at room temperature.