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Lipolytic potential of Aspergillus japonicus LAB01: production, partial purification, and characterisation of an extracellular lipase.

Souza LT, Oliveira JS, dos Santos VL, Regis WC, Santoro MM, Resende RR - Biomed Res Int (2014)

Bottom Line: The optimum temperature was found to be 45°C, and the enzyme was stable for up to 100 minutes, with more than 80% of initial activity remaining after incubation at this temperature.Among the tested ions, only Cu(2+), Ni(2+), and Al(3+) showed inhibitory effects.The KM and V max values of the purified enzyme for p-nitrophenyl palmitate were 0.13 mM and 12.58 umol/(L·min), respectively.

View Article: PubMed Central - PubMed

Affiliation: Cell Signaling, Nanobiotechnology and Enzymology Laboratory, Federal University of Minas Gerais, 31270-901 Belo Horizonte, MG, Brazil.

ABSTRACT
Lipolytic potential of Aspergillus japonicus LAB01 was investigated by describing the catalytic properties and stability of a secreted extracellular lipase. Enzyme production was considered high under room temperature after 4 days using sunflower oil and a combination of casein with sodium nitrate. Lipase was partially purified by 3.9-fold, resulting in a 44.2% yield using ammonium sulphate precipitation (60%) quantified with Superose 12 HR gel filtration chromatography. The activity of the enzyme was maximised at pH 8.5, and the enzyme demonstrated stability under alkaline conditions. The optimum temperature was found to be 45°C, and the enzyme was stable for up to 100 minutes, with more than 80% of initial activity remaining after incubation at this temperature. Partially purified enzyme showed reasonable stability with triton X-100 and was activated in the presence of organic solvents (toluene, hexane, and methanol). Among the tested ions, only Cu(2+), Ni(2+), and Al(3+) showed inhibitory effects. Substrate specificity of the lipase was higher for C14 among various p-nitrophenyl esters assayed. The KM and V max values of the purified enzyme for p-nitrophenyl palmitate were 0.13 mM and 12.58 umol/(L·min), respectively. These features render a novel biocatalyst for industrial applications.

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Michaelis-Menten hyperbola plot for KM and Vmax⁡ values of A. japonicus LAB01 lipase in the presence of various concentrations of p-NPP.
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fig6: Michaelis-Menten hyperbola plot for KM and Vmax⁡ values of A. japonicus LAB01 lipase in the presence of various concentrations of p-NPP.

Mentions: The apparent kinetic parameters for partially purified lipase were obtained from a rectangular hyperbola equation using the SigmaPlot software (version 10.0) (Figure 6). It yielded apparent KM and Vmax⁡ values of 0.13 mM and 12.58 μM·min−1, respectively, for p-NPP as a substrate. Similar kinetic parameters were also found for A. awamori (0.13 mM) [61] and A. nidulans (0.28 mM) lipases [62].


Lipolytic potential of Aspergillus japonicus LAB01: production, partial purification, and characterisation of an extracellular lipase.

Souza LT, Oliveira JS, dos Santos VL, Regis WC, Santoro MM, Resende RR - Biomed Res Int (2014)

Michaelis-Menten hyperbola plot for KM and Vmax⁡ values of A. japonicus LAB01 lipase in the presence of various concentrations of p-NPP.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4230215&req=5

fig6: Michaelis-Menten hyperbola plot for KM and Vmax⁡ values of A. japonicus LAB01 lipase in the presence of various concentrations of p-NPP.
Mentions: The apparent kinetic parameters for partially purified lipase were obtained from a rectangular hyperbola equation using the SigmaPlot software (version 10.0) (Figure 6). It yielded apparent KM and Vmax⁡ values of 0.13 mM and 12.58 μM·min−1, respectively, for p-NPP as a substrate. Similar kinetic parameters were also found for A. awamori (0.13 mM) [61] and A. nidulans (0.28 mM) lipases [62].

Bottom Line: The optimum temperature was found to be 45°C, and the enzyme was stable for up to 100 minutes, with more than 80% of initial activity remaining after incubation at this temperature.Among the tested ions, only Cu(2+), Ni(2+), and Al(3+) showed inhibitory effects.The KM and V max values of the purified enzyme for p-nitrophenyl palmitate were 0.13 mM and 12.58 umol/(L·min), respectively.

View Article: PubMed Central - PubMed

Affiliation: Cell Signaling, Nanobiotechnology and Enzymology Laboratory, Federal University of Minas Gerais, 31270-901 Belo Horizonte, MG, Brazil.

ABSTRACT
Lipolytic potential of Aspergillus japonicus LAB01 was investigated by describing the catalytic properties and stability of a secreted extracellular lipase. Enzyme production was considered high under room temperature after 4 days using sunflower oil and a combination of casein with sodium nitrate. Lipase was partially purified by 3.9-fold, resulting in a 44.2% yield using ammonium sulphate precipitation (60%) quantified with Superose 12 HR gel filtration chromatography. The activity of the enzyme was maximised at pH 8.5, and the enzyme demonstrated stability under alkaline conditions. The optimum temperature was found to be 45°C, and the enzyme was stable for up to 100 minutes, with more than 80% of initial activity remaining after incubation at this temperature. Partially purified enzyme showed reasonable stability with triton X-100 and was activated in the presence of organic solvents (toluene, hexane, and methanol). Among the tested ions, only Cu(2+), Ni(2+), and Al(3+) showed inhibitory effects. Substrate specificity of the lipase was higher for C14 among various p-nitrophenyl esters assayed. The KM and V max values of the purified enzyme for p-nitrophenyl palmitate were 0.13 mM and 12.58 umol/(L·min), respectively. These features render a novel biocatalyst for industrial applications.

Show MeSH
Related in: MedlinePlus