KAJIAN POTENSI EKSTRAK Padina australis (Hauck 1887) SEBAGAI INHIBITOR TIROSINASE ASAL KEPULAUAN SIMEULUE

Seaweed contains bioactive compound which can serve as a defense from ultraviolet radiation that caused hyperpigmentation effect. The brown algae, Padina australis always distributed dominantly at coastal area that various substrates which play important role in biological and ecological system. The aim of this study is to analyse the tyrosinase inhibitory activity of P. australis extract from Simeulue Island Aceh Province. The results showed that the methanol extract of P. australis possessed phytochemical properties such as flavonoids, tannin and saponin. Turn out of Tyrosinase inhibitory activity of P. australis methanol extract had low or no activity to inhibit monophenolase with R-squared (R2 = 0,0542). It showed that variable of inhibition percentage and concentration significantly influenced as much as 5% in monophenolase pathway. Whereas in diphenolase pathway showed that detemination of coefisient was y = -1,82ln(x) + 30,263 dan R² = 0,2966. It showed that variable of percentage inhibition and concentration (ppm) significantly influenced as much as 20% in diphenolase pathway. Thus, it can be concluded that P australis had no activity in tyrosinase inhibitory. Because the inhibition percentage and concentration (ppm) must be influenced positively with level of significant 95%. It can be hypothesized that the human error in laboratory that influenced the extract had no activity in tyrosinase inhibitory