R-ficoeritrina da macroalga Solieria filiformis: fluorescência in vivo e otimização da extração

Abstract

R-phycoerythrin (R-PE) is a photosynthetic pigment (phycobiliprotein) present in red macroalgae, which has wide industrial applications. The presence of polysaccharides in the cell wall of macroalgae hampers pigment extraction. Thus, biotechnological tools can be used to optimize this process. Therefore, the R-PE localization in the thallus, the extraction and the effect of the cellulase on the R-PE extraction from Solieria filiformis macroalga, a species cultivated on the coast of Ceará, Brazil, were evaluated. Laser confocal microscopy was used to identify the pigmented cells in the tallus. It was observed that freezing as a preservation method caused morphological modifications of the thallus, however, the pigmentation was preserved. The effect of the cellulase concentration, temperature and time were evaluated on the yield and purity index of the pigment extracted. Only thallus cortical cells presented R-PE fluorescence and the highest R-PE yield extraction observed (0.1921 ± 0.0086 mg g-1 wet macroalga) was in the presence of the cellulase from Aspergillus niger at 200 U g-1 wet macroalga. The concentration enzyme, temperature and time positively influenced the R-PE extraction yield, but negatively influenced the pigment purity index. The best condition to extract the R-PE was 160 U g-1 wet macroalga, temperature 35 ºC by 6 h, reaching 0.21 mg g-1 wet macroalga, with a purity index of 0.04.