摘要
Allophycocyanin (APC) was purified from Spirulina platensis using hydroxylapatite chromatogra-phy and ion-exchange chromatography. Effects of solution pH on spectra of APC were studied APC has anabsorption maximum at 650 nm, and a shoulder at 620 nm The fluorescence emission peak is at 660nm. Theefficiency of energy absorbing and transfer in APC could be reflected by the absorption spectra and fluorescencespectra, respectively. Structural variations of APC could be monitored by means of circular dichroism spectraAPC showed good absorbance and fluorescence stability at varying pH with only minor changes between pH 4-10. The trimeric structure of APC was maintained while local variations of protein peptides were allowed in re-sponse to the environmental disturbance Beyond this pH range, secondary structure as well as overaU confor-mation of APC dramatically changed, and the energy absorption and transfer ability were also disrupted