Development and clinical efficacy evaluation of anti-greasy green tea tonner on facial skin

ABSTRACT

ABSTRACT Green tea (Camellia sinensis (L.) Kuntze, Theaceae) polyphenols have activities against skin disorders; however, anti-sebum efficacy of green tea cosmetic has sparely been reported. The facial tonner containing green tea was therefore developed and clinical evaluated. The base formulas which stabled following accelerated tests were sensorial assessed in ten volunteers. The base with hydroxyethyl cellulose, glycerin and panthenol (totally 3.6%) with the significant (p < 0.05) preference (82.3 ± 0.55%) over the others was further developed to green tea preparations. All of the products were stable and caused none of skin irritation as closed patch tested in twenty volunteers. Thereafter, they were clinical evaluated in the same group of the volunteers and monitored with Sebumeter® by means of a split-face, randomized single-blind, placebo-controlled study. Anti-greasy efficacy of 2, 4.5 and 7% green tea tonners were 3.47 ± 0.10, 8.18 ± 0.44 and 17.87 ± 0.46% following 14 days of facial treatment. The efficiency was pronounced at the end of the study; day 28 (8.48 ± 0.13, 20.26 ± 1.03 and 31.57 ± 1.22%). Anti-sebum efficacy of the 4.5 and 7% green tea tonners were significantly better than the base formula (day 14; p < 0.05, day 28; p < 0.01). The efficacy of 28 days treatment was significantly better than 14 days (p < 0.05). The safe and efficient green tea tonner for oily face treatment was therefore approved in this context.