Figure 6.

Time-course profiles of the relative antioxidant activity of free HT (▼) and HT monoesters based on different alkyl-chain lengths (C₆, △; C₈, ■; C₁₀, □; C₁₂, ◆; C₁₄, ♢; C_18:1, ▲; overall content in HT species: 80 nmol), determined spectrophotometrically at 517 nm during 4 h with DPPH. Vitamin C (80 nmol, ○) was used as an antioxidant standard reference. A sample of DPPH without any antioxidant (●) was used as a control to establish the zero value. Insert picture: final color displayed by each sample after the DPPH test.