Mechanism Underlying Green Discolouration of Myoglobin Induced by Atmospheric Pressure Plasma

摘要: In this study, we elucidated the mechanism underlying atmospheric pressure plasma (APP)-induced green discolouration of myoglobin. Green-coloured pigments are produced upon conversion myoglobin into sulphmyoglobin, choleglobin, verdoheme, nitrihemin, or nitrimyoglobin. We exposed dissolved in phosphate buffer to APP for 20 min and found a decrease a* value (+redness/−greenness) increase b* (+yellowness/−blueness) (P < 0.05). ultraviolet absorption spectrum, treated with showed peaks at 503 630 nm, spectrum different from that sulphmyoglobin choleglobin. The secondary structure molecular weight were unaffected by treatment, excluding possibility verdoheme nitrihemin formation. After nitrite was solution provided positive environment nitrimyoglobin However, addition 0.5% sodium dithionite, strong reducing agent, resulted formation deoxymyoglobin, which subsequently converted nitrosomyoglobin treatment yield desirable red colour. Thus, APP-induced colouration is associated antioxidant production colour after owing