Abstract
Activities and partial characterization of lysozyme in the skin mucus extract, serum and kidney extract of yellowtail Seriola quinqueradiata, were investigated. The lysozyme activities were measured using acetone-ether dried cells of Micrococcus lysodeikticus as substrate. The lysozyme activities in the skin mucus extract, serum and kidney extract were 0.69, 3.00 and 2.23μg/mg protein, respectively. The optimal pH for the lysozyme activities of skin mucus extract was around 7.0, whereas that of serum and kindey extract were around 8.0. The optimal temperature for the lysozyme activity of skin mucus extract was around 40°C, and similar results were obtain in serum and kidney extract. The lysozyme activities were relatively stable to heat, and remained active when heated at 50°C for 10min. The lysozyme activities were inhibited by incubation with EDTA and were inactivated when chitin coated cellulose was added to the samples.
