NADPH containing superoxide-producing thermostable complex from raspberry, apricot, grape, and grape seeds: isolation, purification, and properties

Background NADPH oxidase (Nox) plays a crucial role in reactive oxygen spices (ROS) production and mediates different diseases’ development. Under aerobic conditions, the NADPH-containing protein component of the (NCP)-Fe (III) complex produces O 2 − continuously and intensively. However, after the removal of Fe (III), the isolated NCP shows only antioxidant properties at the expense of NADPH composite. Based on the fact that the mentioned fruit juices are widely used in everyday life and also in biomedicine, it was aimed to use a universal method: 1. to obtain superoxide generating complex from available and relatively cheap raw materials without using any toxic substances; 2. to isolate, purify and study the components of prooxidant nature: the isoforms of O 2 − —producing NCP-Fe (III) complexes obtained from Armenian fruits (raspberries, apricot, grapes), as well, grape seeds. Results Using a licensed method, for the first time isoforms of the superoxide (O 2 − ) producing a thermostable complex of the NCP component with Fe (III), (NCP-Fe (III)), were isolated and purified from Armenian fruits—raspberries, apricots, grapes, and grapes seeds. The process of isolation and purification of isoforms of these complexes included the following stages of processing: 1. alkaline hydrolysis at pH9,5; 2. their sedimentation at pH4.8; 3. Dissolving of the sediments in water at pH9.5, followed by ion-exchange chromatography on cellulose DE-52, and gel filtration on Sephadex G-100. Further, the heat treatment of the mentioned complexes was carried out. In a lyophilized state, under the anaerobic conditions, the isoforms of the given complexes, hybrid associates (hNCP-Nox), and NCP were stored practically without losing their activity in a mass of 1–1.5 g. Conclusions Isoforms of O 2 − -producing complexes are new liquid-phase, thermo-stable prooxidant components found in raspberries, apricots, grapes, and grapes seeds.