Extraction and characterization of hyaluronic acid from the eyeball of Nile Tilapia (Oreochromis niloticus)

Hyaluronic acid (HA) is a biopolymer of enormous value aggregation for in general industry. The vitreous humor of the eyeball from Nile tilapia contains appreciable amounts of hyaluronic acid. In this sense, the aim of this work was to extract and characterize hyaluronic acid from the eyeball of the Nile tilapia for biomedical appli-cations, adding value to fish industry residues. The characterization by infra-red (FTIR), 13C nuclear magnetic resonance (NMR) and high performance liquid chromatography (HPLC) confirmed that hyaluronic acid was obtained. The gel permeation chromatography (GPC) showed that the obtained material presents a low mo-lecular mass (37 KDa). Thermogravimetry (TGA), differential scanning calorimetry (DSC), X-ray diffraction (XRD) analysis showed that the materials present a thermal stability superior to the commercial hyaluronic acid from Streptococcus equi , with a partially crystalline character. The cytotoxicity assay (MTT method) with fibro-blast cells (L929) demonstrated that the extracted biopolymer besides not being cytotoxic, was able to stimulate cell proliferation. Therefore, the hyaluronic acid extracted from this source of residue constitutes a product with biotechnological potential, which has adequate quality for wide biomedical applications.

Automated summary

The aim of this study was to extract and characterize hyaluronic acid (HA) from the eyeball of Nile tilapia, which is a valuable resource in fish industry residue. Characterization through FTIR, 13C NMR, and HPLC confirmed the presence of HA. GPC analysis revealed a low molecular mass of the extracted material. Thermal analysis and XRD showed that the extracted HA had superior thermal stability and partially crystalline characteristics compared to commercial HA. Cytotoxicity assay demonstrated that the extracted HA was not cytotoxic and could stimulate cell proliferation, indicating its potential for biomedical applications.