Lysozyme activity was measured according to the turbidimetric
method described by Parry et al. [38] with somemodifications. One
hundred ml of skinmucus diluted 1/2 with 10mMPBS, pH 6.2, were
placed in flat-bottomed 96-well plates in triplicate. To each well,
100 ml of freeze-dried Micrococcus lysodeikticus (0.3 mg ml
1
,
Sigma) was added as lysozyme substrate. The reduction in absor-
bance at 450 nmwasmeasured after 0 and 15min at 22 C in a plate
reader. One unit of lysozyme activity was defined as a reduction in
absorbance of 0.001 min1
. The units of lysozyme present in skin
mucus were obtained from a standard curve made with hen egg
white lysozyme (HEWL, Sigma) and the results expressed as
Umg1
mucus proteins.