Purification of Marine Fish Proteins

The fish species barfin plaice (Liposetta pinnifasciata), longsnout poacher (Brachyopsis rostratus), notched-fin eelpout (Zoarces elongatus Kner), and saffron cod (Eleginus gracilis) were collected by Nichirei Corporation. Size exclusion chromatography and anion exchange chromatography were successively performed for the prepared crude sample powders with a Sephadex G-25 size-exclusion column (XK 50/30, 500 mL; GE Healthcare Life Sciences, Pittsburgh, PA, USA) and DEAE Sepharose anion-exchange column (XK 50/20, 80 mL; GE Healthcare), respectively [7 (link)]. The purified samples were dialyzed against Milli-Q water for three overnights, and then lyophilized for frozen storage. The purity of the final product was checked with 15% SDS–PAGE using a minislab electrophoresis kit (AE-6500; ATTO Corp., Tokyo, Japan).