CHARACTERIZATION OF ISOENZYMES, ENZYME ACTIVITIES AND PROTEIN PROFILES OF ROASTED PEANUT (ARACHIS HYPOGAEA L.)

Unsalted and salted peanut (Arachis hypogaea L.) samples were roasted at 180°C at different periods (0, 3, 5, 10, 20, and 45 min). Different protein fractions (total soluble protein, albumin, globulin and SDS-ME) were separated using different solvents. Activities of AP, LOX, POX and PPO were estimated in total soluble protein fraction of roasted as well as unroasted peanut. The results showed that the peanut protein solubilities were variable and dependent on roasting temperature. The protein profile of roasted peanut samples showed that most of albumin bands started to change after 20 min roasting time as well as the major arachin globulin protein started to disappear. AP, LOX, POX and PPO activities showed significant decrease as a result of roasting process. Polyacrylamide gel electrophoresis revealed high activities of EST, CAT and AP in control samples compared with the treated samples. While the activities of the aforementioned enzymes were decreased gradually by increasing roasting temperature until disappearance completely at 180°C for 20 min.