Extraction and fractionation of lipolytic enzyme from viscera of Monterey sardine (Sardinops sagax caerulea)

In this study, lipolytic activity of a semi-purified lipolytic enzyme (SLE) from the viscera of sardine (Sardinops sagax caerulea) was screened on the lipolysis of olive, Menhaden and sardine oil. A lipolytic enzyme was partially purified from the crude extract of sardine viscera by fractional precipitation followed by ultrafiltration (30 kDa). The main tissues found in sardine viscera were pyloric caeca (19.0% w/w), digestive tract (13.0% w/w), liver (4.8% w/w) and pancreas (1.5% w/w). Results show that pancreas had the highest lipolytic activity. There were no significant differences in lipolytic activity between pyloric caeca, intestine and liver (P < 0.05). Specific activity of the SLE increased 47.0-fold after extraction and fractionation, with a yield of 0.34% calculated for the whole viscera weight. Lipolytic activity of SLE from sardine viscera increased threefold when sardine oil was used as substrate. The results of this study confirm the potential importance of lipases from marine sources.