الفهرس | Only 14 pages are availabe for public view |
Abstract Peanut (Arachis hypogaea L. variety Giza 5) seed contained 26.3 % crude protein. This seed contained inhibitor which inhibited both trypsin and chymotrypsin. Thus, it would be referred to as peanut protease inhibitor. The defatted meal was prepared from seeds by cold acetone. EXTRACTION OF Peanut PROTEASE INHIBITOR: Four different extractants were examined for extracting TIA. Although distilled water Was effective as the other three acidic extractants (20 mM HCI, 2.5% TCA and 50 mM acetic acid), the specific activity of TIA and CIA was the highest in 50 mM acetic acid extract which was used for extracting the Inhibitor for purification. ACETONE FRACTIONATION: Preliminary experiment indicated that protein precipitating from 50 mM acetic acid extract by acetone fractionation (between 50 and 70% acetone concentration) contained most inhibitory activity. This step achieved about 3 fold increase In the specific activity with recovery of 70%. PURIFICATION OF PEAIIUT PROTEASE Inhibitor : Peanut protease inhibitor was purified to homogeneity through, acetic acid extraction, acetone fractionafion (using the protein precipitating between 50 and 70% of acetone concentration), anion exchange chromatography on DEAE celiulose column, chromatography on hydroxyapatit column and molecular sieve chromatography on Sephadex G-75 column. |