2.3. Total phenolics content measurement
The total phenolics (TP) content was analysed according to the
Folin-Ciocalteu procedure of Swain and Hillis (1959) with slight
changes. Frozen tissue samples (5 g) were extracted in methanol
(25 mL). The obtained homogenates were preserved in covered
centrifuge tubes for 12 h in darkness at 4 C, and centrifuged at
12,000 g for 20 min. The extract supernatants were used for TP
analysis. TP content was expressed as g kg 1 of GAE on a fresh
weight basis