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In this study, Penicillium sp. section Gracilenta CBMAI 1583 was used to produce lipase under submerged conditions. The enzyme was purified and the biochemical properties of both the crude and purified enzymes were evaluated. Maximum lipase production (1.62 U mL−1) was obtained using olive oil 0.5% (w v−1) after 72 h of cultivation, representing a 90% increase in the lipase initially produced. The enzyme was purified using hydrophobic interaction chromatography (phenyl Sepharose) under conditions which allowed its interfacial activation. The partially purified sample showed an enzyme with esterase activity (65.4 kDa) on α- and β-naphthyl acetate and other with lipase activity (52.9 kDa) on octyl oleate. Optimum activity of crude and purified lipase was observed at pH 4.0 and 70 °C. The purified lipase was activated by NaCl, BaCl2, NH4Cl, MnSO4 and MgSO4; it also presented high stability in organic solvents such as hexane, 2.2.4-trimethylpentane, acetone, DMSO and toluene. Maximum enzyme activity was observed with p-nitrophenyl decanoate as substrate; and the enzyme kinetics showed to be directly affected by Triton X-100. The enzyme shows potential application in processes that operate in acid pH, such as treatment of dairy and industry effluents, resolution of esters in the pharmaceutical industry or in the food industry, as well in synthesis reaction under non-aqueous conditions., The authors gratefully acknowledge to São Paulo Research Foundation - FAPESP, Brazil, for the scholarship granted to the first author and Spanish Ministry of Science and Innovation - MICINN, Spain (Project BIO-2012–36861).

Most of the triacylglycerol hydrolase activity in the hen liver showed its maximum activity at pH 6.0 and at 40°C. The hydrolase activity was markedly inhibited by serum of the laying hen. At 145 and 167 days of age, the activity was markedly decreased to less than one half that in the young hen. The hydrolase activity in cockerel was monitored to compare with that of hen. In cockerels, the hydrolase activity tended to increase with age of days. On estrogenization of the male chicks, the hydrolase activity in the liver was significantly decreased in contrast to an increase in lipid content in the liver. These observations suggest that the degradation of triacylglycerol in the liver is regulated by estradiol with the increase in lipogenesis for egg production.