2.6.9. Determination of antioxidant activity of H. erinaceus extract, wine and vinegar
ABTS and 2.2′-azobis (2-amidinopropane) dihydrochloride (AAPH) were dissolved in phosphate-buffered saline (PBS, containing 150 mM NaCl) in a 1:1 ratio and the mixture was incubated in a 37 °C water bath to an absorbance at 734 nm. An aliquot of each sample was mixed with ABTS solution. After incubation at 37 °C for 10 min, the absorbance was determined again at 734 nm. The concentration of ABTS was expressed as mg ml−1 of extract. Radical-scavenging activity was determined in accordance with the method of Brand-Williams, Cuvelier, and Berset (1995). The reaction was initiated by adding 20 μl of sample. The bleaching of DPPH was determined at 515 nm at 25 °C for 20 min. The antioxidant activity was calculated as follows: Antioxidant activity (%) = [(Absorbance of control - Absorbance of sample)/Absorbance of control] × 100.