Extracción y caracterización preliminar de pigmentos y colágeno a partir de medusas Stomolophys meleagris, Aurelia aurita, Rhizostoma pulmo y Rophilema esculentum

Abstract

Due to consumers' demand for natural pigments new sources have been explored, the marine environment among others. This paper studied the optimal extraction conditions and preliminary characterize a blue pigment obtained from Stomolophus meleagris jellyfish. Specimens were collected from State of Sonora seashore, at the Gulf of California, Mexico. The umbrella color was not homogeneous where a more intense blue color was observed at the edge. The pigment was obtained after tissue sonication at 35 kHz and extraction with artificial seawater, and purified by ultrafiltration through 30 and 100-kDa MCD membranes. The pigment is not a carotenoid, as concluded by it insolubility in non-polar solvents. A 100 kDa protein was associated to the chromophore, conversely with other jellyfish species where the protein moiety is around 30 kDa. This higher protein molecular weight was possible due to a multimeric glycoprotein. By using PAS staining it was concluded that this pigment is a glycoprotein, showing similar characteristics to the blue pigment extracted from Casiopea xamachana and Rizostoma pulmo. The associated protein was separated from the pigmentprotein complex using two commercial proteases. Pigment stability was followed during storage for 35 days at 4 and -20 o C. The obtained partially purified pigment was efficiently extracted with 10% ethanol, stable at pH 3 to 9, but not stable to heating.