In vitro Anti-acne Properties of Plant Extract Complex Composed of Camellia sinensis L. Leaf and Castanea crenata Bur

This study aims to investigate the anti-acne efficacy of the plant extract complex (PEC) consisting of Camellia sinensis L. leaf and Castanea crenata bur extract in vitro. The effect of PEC on anti-acne target including sebum production, Cutibacterium acnes (C. acnes)-induced inflammation, 5-alpha reductase activity and free radical scavenging activity was observed. The level of lipid production was measured through nile red staining in sebocytes to confirm the effectiveness of inhibiting sebum production, and C. acnes cultured medium (C. acnes CM) were treated on HEK293-hTLR2 cells to observe TLR2 activity. In addition, regulation of 5-alpha reductase activity was confirmed using rat liver microsomes, and antioxidant capacity was measured by DPPH assay. As a result, PEC showed the inhibitory effect on sebum production up to 59.02±5.13% at 100 μg/mL and the C. acnes CM with PEC treated group dramatically inhibited the TLR2 activity as much as the control level. At 100 μg/mL of the PEC, the activity of 5-alpha reductase enzyme activity was suppressed by about 20% compared to the group treated with rat microsomes, and the radical scavenging capacity was measured at 86.83±10.19. These results suggest that PEC, a complex extract of Camellia sinensis L. leaf and Castanea crenata bur, can be used as natural cosmetic raw materials that can relieve acne through inhibition of excessive sebum production, reduction of 5-alpha reductase activity, anti-inflammatory, and antioxidant properties.