[Antioxidant properties of UV-irradiated blood plasma as determined by the photochemiluminescence method].

UV-irradiation of human serum albumin, tryptophan, and histidine resulted in products formation showing antiradical activity, as detected by increased latent period in development of luminol photochemiluminescence. UV-irradiation of ascorbic acid decreased its antiradical activity. Under UV-illumination, antiradical activity of blood plasma decreased rapidly followed by a gradual increase of antiradical activity. Apparently, the former effect (decrease of antiradical activity) is a result of photolysis of natural blood antioxidants, while subsequent increase of antiradical activity is a consequence of the accumulation of plasma protein photolysis products.