Antioxidant activity (DPPH and ABTS methods, expressed as TE, and TPC expressed as GAE) of Mentha x rotundifolia MR16 extracts obtained by UAE, MAE, and SWE at 50ºC for 5 min

TechniqueTPC (GAE, mg mL–1)ABTS (TE, mg mL–1)DPPH (TE, mg mL–1)
UAE bath5.7 (0.1)*,a3.3 (0.2)a,b4.4 (0.5)c
UAE 12 mm probe3.38 (0.06)c2.4 (0.5)b5.0 (0.9)c
UAE 3 mm probe1.85 (0.04)d1.7 (0.2)b2.6 (0.8)d
MAE3.03 (0.06)c4.3 (0.5)a9.9 (0.9)b
SWE4.5 (0.2)b4.3 (0.1)a11.2 (0.5)a

Mean value and standard deviation in parentheses (n = 3); a,b,c,d different letters in the same column indicate significant (P < 0.05) differences among the techniques evaluated