UV-absorbing pigments in eye tissues of fish from the Great Barrier Reef

Ocular tissues from 52 species (19 families) of tropical marine fish were examined for levels of UV-absorbing pigments in the spectral region 300-380 nm.Specimens of mackerels, tuna and marlin were caught by surface trolling in Bowling Green and Upstart Bays; all other fish were caught by hand-line or spearfishing at Grub, Hunt and Marion Reefs. The eyes were removed and frozen immediately at -20°C. Lens ocular tissues were excised from defrosted samples, crushed and extracts formed by steeping in 5ml methanol. Visible-u.v. absorption spectra from these extracts were recorded. Solid protein biomass was determined from the solid tissue residues. Mycosporine-like amino acids (Asterina-330, palythene, palythine and palythinol) were separated and quantified (nmol/mg protein) using reverse-phase isocratic high-performance liquid chromatography (HPLC).The efficiency of methanol extraction This research was undertaken to:1. identify and describe the distribution of mycosporine-like amino acid compounds in the lens tissues of marine fish2. develop techniques for quantitative studies of UV absorbing compounds in fish eyes using high performance liquid chromotography3. evaluate the efficiency with which these compounds can be extracted from lens tissues