COUNTERCURRENT CHROMATOGRAPHIC ANALYSIS OF OVALBUMIN OBTAINED FROM VARIOUS SOURCES USING THE CROSS-AXIS COIL PLANET CENTRIFUGE

The present studies have been conducted to investigate the cause of an unusually broad peak of ovalbumin obtained by countercurrent chromato graphy (CCC) reported earlier [K. Shinomija et al., J. Chromatogr., 64 4 (1993) 215]. A series of CCC experiments using our prototyte of the cross-axis coil planet centrifuge revealed that commercial ovalbumin p roducts were classified into two groups: group A formed two peaks of o valbumin at pH 7.0 and 5.8, while group B showed a relatively sharp si ngle peak in a broad range of pH. Electrophoresis indicated that the g roup A ovalbumin consisted of both natural and denatured products: the natural ovalbumin is a monomer (M(r) 45 000) whereas the denatured pr oducts form dimers (M(r) 90 000). The abnormally broad peak obtained f rom the group A ovalbumin at pH 9 is apparently caused by the heteroge neity of the sample protein.