Isolation and purification of diamine oxidase from green peas and study its properties

This research included isolating diamine oxidase from green pea extract and partially purifying it, as well as determining its approximate molecular weight, after diamine oxidase was isolated using different biotechnologies. The protein compounds of ammonium sulphate precipitate solution were separated at a saturation rate of 65%, using gel filtration chromatography technology on a separation column containing Sephadex G-100 gel. Results show two clear bands. Band A was excluded, because its activity of diamine oxidase was very low compared to band B. Specific concentration of diamine oxidase in B peak reached (61.32 ng/ml), number of purification times was (3.58 times) and recovery rate was (14.25%) for pea extract. Also, gel filtration technique using G-100 was used to estimate approximate molecular weight of diamine oxidase, which showed that enzyme has a molecular weight of approximately 112,201 daltons. In addition, effect of inhibitors and stimulants on activity of isolated enzyme was studied. Therefore, when using Zolmitriptan and the commonly used headache medicine - Panadol - it was found that former achieved greatest ability to increase effectiveness of diamine oxidase, while elements such as lead and potassium showed that lead has Greater ability to reduce activity of diamine oxidase compared to potassium, which is a less severe inhibitor of diamine oxidase isolated and purified from green peas.