Purification of basic fibroblast growth factor and alkaline phosphatase from human placenta.
Human placenta is an available hospital waste which is known to contain many valuable biochemicals that may be commercially exploited. Using placental tissue previously extracted for haemoderivatives, we purified basic fibroblast growth factor (bFGF), a soluble protein, and placental alkaline phosphatase (PALP), a membrane-linked protein, as a coupled process. bFGF purification comprises three steps: extraction and chromatographies on S-Sepharose and heparin-Sepharose. The final product includes a major 17 kDa and a minor 16 kDa component with a specific activity of 8.0 x 10(6) units/mg yielding 0.5-1.0 microgram/kg of placenta. PALP purification comprises four steps: acidic butan-1-ol extraction and chromatographies on Q-Sepharose, concanavalin A-Sepharose and Q-Sepharose. The purified PALP has a molecular mass of 70 kDa, a specific activity of 800 units/mg and yielded 50 micrograms/kg of placenta. The results show the possibility of purifying substances in placental haemolysed blood, soluble products from placental cellular mass and proteins from the cellular membrane in a one-stream process.