Enzymatic treatment of hair with or without reducing agents.

(A) Hair samples treated with 0.2, 1 or 2 KU/mL Ronozyme ProAct or Cibenza DP100 for 16 h at 37°C with or without reducing agents. The extent of hair degradation can be seen by the disappearance of the hair fibre and the increased colouration of the solution, possibly due to melanin release from the brown hair. (B) Soluble peptides after hair treatment with 0.2, 1 or 2 KU/mL of Cibenza DP100 or Ronozyme ProAct for 16 h at 37°C in the presence of reducing agents. The control is defined as the hair sample treated in buffer solution without enzyme. Data are represented as means ± SD (n = 3).