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INTRODUCTION
Lipases (triacylglycerol acyl hydrolase, EC 3.1.1.3) are water-soluble enzymes that catalyze the hydrolysis of ester bonds from insoluble triacylglycerides, releasing free-fatty acids, mono or diacylglycerides in the oil-water interface (Treichel et al. 2010). These enzymes catalyze a wide range of reactions such as hydrolysis, esterification, trans-esterification, alcoholysis, acidolysis and aminolysis (Joseph et al. 2008), and can vary in their catalytic properties as a function of their origin, which can be animal, microbial or from plants. Microbial lipases can be obtained by solid-state fermentation or submerged fermentation (Annibale et al. 2006; Rigo et al. 2010; Papagora et al. 2013).
The use of hydrolytic enzymes is of great interest for the treatment of effluents with high-lipid content. Some studies have reported the use of lipases in wastewater treatment of dairy, meat, oil industries and restaurants, as an alternative to conventional effluent treatment (Dharmsthiti & Kuhasuntisuk 1998; Jung et al. 2002; Jeganathan et al. 2007; Ertugrul et al. 2007). The use of lipases in effluents with a high-lipid fraction has the objective of hydrolyzing triacylglycerides, because the oils and fats are inhibitory degradation compounds in processes of wastewater treatment.
Lipids contained in this type of effluent, besides representing an important industrial loss, negatively interfere in Wastewater Treatment Systems. High concentrations of lipids result in layers of fat in the treatment ponds, which impairs the oxygen transfer, leading to mortality of microorganisms and aquatic life (Mendes & Castro 2004). Under Brazilian law, up to 50 mg L−1 of fats and oils are permitted in the discharge of effluents. Thus, to comply with legal requirements, alternative processes have been developed in order to reduce the lipid concentration in wastewater by the action of enzymes, particularly lipases (Lima et al. 2004).
In the last two decades, the fries processing industry has gained importance in the Brazilian scenario, mainly supplying the fast food market. In the industrial processing of fried potatoes, the generation of waste with high concentrations of oil and grease after frying, occurs mainly during the cleaning of fryers (Fernandes et al. 2008).
From the presented considerations, this study aimed to analyze the physical and chemical characteristics of commercial lipase Amano PS - Burkholderia cepacia and lipase produced by Burkholderia cepacia, strain ATCC 25416, in addition to studying the...