Identification of black sturgeon caviar pigment as eumelanin. (30th March 2022)

• Record Type: Journal Article
• Authors: Panzella, Lucia; Benning, Kenneth; Nesbeth, Darren N.; Setaro, Brunella; D'Errico, Gerardino; Napolitano, Alessandra; d'Ischia, Marco
• Is Part Of: Food chemistry. Volume 373:Part B(2022)
• Publication Date: 2022-03-30
• Subjects: Black caviar -- Sturgeon roe -- Melanin -- Electron paramagnetic resonance (EPR) -- Pyrrole-2, 3, 5-tricarboxylic acid (PTCA); Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2021.131474
• Languages: English
• ISSNs: 0308-8146

Abstract

Highlights: The black pigment of sturgeon roe (SRBP) was purified by sequential centrifugation. Electron paramagnetic resonance allowed to identify SRBP as a eumelanin. A specific eumelanin marker was detected in SRBP chemical degradation mixture. This is the first clear-cut demonstration of the occurrence of melanin in a fish roe. The presence of melanin was detected also in a caviar oil production by-product. Abstract: Reported herein is the purification of the pigment of black sturgeon caviar and its unambiguous identification as a typical eumelanin by means of chemical degradation coupled with electron paramagnetic resonance (EPR) evidence. HPLC and LC-MS analysis of oxidative degradation mixtures revealed the formation of pyrrole-2, 3, 5-tricarboxylic acid (PTCA), a specific marker of eumelanin pigments, in yields compatible with a 6.5% w/w pigment content. EPR spectral features and parameters were in close agreement with those reported for a typical natural eumelanin such as Sepia melanin from squid ink. The identification for the first time of eumelanin in a fish roe is expected to provide a novel molecular basis for the valorization of black caviar and production wastes thereof in food chemistry and diet.