Table 1.

Extraction procedures.

	Extraction A	Extraction B	Extraction C
Preparation		A 5 mm steel ball was put in each sample tube. The tubes were put in aluminium holders (especially constructed for this purpose) and submerged in liquid nitrogen for 2 minutes.
Disintegration		The sample tubes were quickly transferred to the ball mill and grinded for 2 min at 23 Hz.	The samples were incubated with 100 µL 1 M NaOH at 95 °C for 10 min. When the tubes recovered to RT 100 µL 1 M HCl was added.
Incubation with methanol	1 mL of MeOH was added to each sample. The tubes were incubated in RT on a shaker for 24 hours.	1 mL of MeOH was added to each sample. The tubes were incubated in RT on a shaker for 20 hours.	1 mL of MeOH was added to each sample. The tubes were incubated in RT on a shaker for 20 hours.
Centrifugation and evaporation	The samples were centrifuged at 1922 g for 10 min, 700 µL of the supernatant was transferred to new tubes and the methanol evaporated.	The samples were centrifuged at 1922 g for 10 min, 700 µL of the supernatant was transferred to new tubes and the methanol evaporated.	The samples were centrifuged at 1922 g for 10 min, 700 µL of the supernatant was transferred to new tubes and the methanol evaporated.

Abbreviations: MeOH, methanol; RT, room temperature; NaOH, sodium hydroxide; HCl, hydrochloric acid.