The feed samples were ground into fine particle. Ground feed
(25.0 g) was mixed with 125 mL of 70% (v/v) methanol (chromatographic
grade, Merck KGaA, Darmstadt, Germany) and 5.0 g of
NaCl in a 250 mL triangular flask, and then sonicated for 30 min.
The mixturewas then filtered with quantitative filter paper, and the
filtratewas diluted twice with Milli Qwater. The diluted filtratewas
retained for purification.