Fractionation and Purification of Bioactive Compounds Obtained from a Brewery Waste Stream

Table 2

Recovery yield, radical scavenging activity (DPPH), and colouration of each fraction (Fr.) obtained by SPE with different % of methanol.

Sample	% of methanol	Recovery yield (% w/w)^a	DPPH (EC50)^b	Colour
Fr. 1	0	10.4	0.44	Wheat
Fr. 2	10	18.1	0.30	Burnt orange
Fr. 3	20	16.2	0.27	Brown
Fr. 4	30	19.4	0.20	Maroon
Fr. 5	40	18.3	0.26	Dark brown
Fr. 6	50	8.19	0.23	Dark brown
Fr. 7	60	6.71	0.89	Ochre
Fr. 8	70	1.59	7.02	Colourless
Fr. 9	80	0.324	6.64	Colourless
Fr. 10	90	0.615	8.25	Colourless
Fr. 11	100	0.194	14.3	Colourless
Crude extract	—	—	0.32	Dark brown
BHA	—	—	0.24	—
BHT	—	—	2.67	—

^aValues expressed as % of dry crude extract.
^bValues expressed as g L⁻¹ of extract (fraction).