Abstract

Agarophyton chilense (Pelillo) is a red macroalgae found along the Chilean coast. It has a great relevance for the country's economy, being Chile one of the main producers of red seaweed worldwide exporting about 60,000 dry tons annually. The main application currently given to Pelillo is agar extraction. On the other hand, phycobiliproteins (PBPs) are intracellular photoreceptor protein pigments which can be also extracted from this seaweed. It has been reported that PBPs have antioxidant and antitumor properties, among others, being attractive for the pharmaceutical and biotechnology industries. PBPs are divided into three main groups: Phycoerythrin, Phycocyanin and Allophycocyanin. The main goal of this work is to provide an added value product from Pelillo by means of the sequential extraction of PBPs and agar from the residual matter, after PBPs extraction. To carry out our purpose, the seaweed was incubated with PBS buffer and proteins were precipitated with ammonium sulphate. PBPs were purified from dialyzed protein fractions using anion-exchange chromatography. Agar was extracted after alkali treatment and neutralization of algae residue. We found no differences in agar quality from samples treated with and without a previous PBPs extraction step. Our work results demonstrate that it is feasible to recover agar from the residual matter after PBPs extraction. The recovery of PBPs from crude extract was 10% and agar yield from dry algae was approximately 25%. In addition, the method developed reduced the amount of alkaline solution when compared to the traditional direct agar extraction method. Acknowledgements: Centre for Biotechnology and Bioengineering (CeBiB) Basal Grant FB-0001 and Fondecyt Grant Number 1180794.