Optimization of extraction and purification process of hyaluronic acid from fish eyeball

The goal of the present work is to optimize the different steps for obtaining highly purified hyaluronic acid (HA) from fish eyeball. The extraction and purification process of HA from vitreous humour of fish, among other biological materials, is based on the succession of: (1) a step of protein electrodeposition, previous or simultaneous with a diafiltration process in total recirculation, (2) a selective recovery in hydroalcoholic solution of impure sediments obtained by alcoholic exhaustive precipitation, (3) an alkaline treatment under hydroalcoholic solution and controlled conditions of alkalinity, temperature, proportion of ethanol and time that it precipitates HA and solubilises proteins, and (4) HA recovery by alkaline suspension of the precipitate in hydroalcoholic phosphate monosodium that it dissolves HA, neutralizes the extract and leaves insoluble proteins in the sediment. Thus, HA with high purity (more than 99.5%), useful for clinical and cosmetic applications, are obtained by means of low-cost process using a waste material. (C) 2011 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.