Production and characterization of alkaline extracellular lipase from newly isolated strain Aspergillus awamori HB-03

  • Jin-lan Xia (夏金兰)
  • Bin Huang (黄斌)
  • Zhen-yuan Nie (聂珍媛)
  • Wei Wang (王威)
Article

DOI: 10.1007/s11771-011-0857-5

Cite this article as:
Xia, J., Huang, B., Nie, Z. et al. J. Cent. South Univ. Technol. (2011) 18: 1425. doi:10.1007/s11771-011-0857-5

Abstract

A strain HB-03 to produce alkaline extracellular lipase was isolated from oil-rich soil samples and identified as Aspergillus awamori. The growth conditions and nutritional factors for lipase production by strain HB-03 were optimized, and the maximum lipase production of (45.9±2.3) U/mL was obtained at 30 °C and pH 7.0 after 36 h using olive oil (1%) and sucrose (0.5%) as carbon sources and combination of peptone (2%), yeast extract (0.5%) and ammonium sulfate (0.1%) as nitrogen sources. The lipase was purified to homogeneity with 10.6-fold, 18.84% yield and a specific activity of 1 862.2 U/mg using ammonium sulfate precipitation followed by SephadexG-75 gel filtration chromatography. The purified lipase with molecular mass of 68 ku was estimated by SDS-PAGE. The optimum pH and temperature for the purified lipase were found to be 8.5 and 40 °C, respectively. The lipase kept more than 80% of activity in pH 7.0–10.0 and temperatures up to 45 °C. The metal ions of Mn2+, Ba2+ significantly enhanced the lipase activity, whereas Cu2+, Fe3+ and Mg2+ strongly reduced the lipase activity. The Km and Vmax values of the purified enzyme for p-nitrophenyl palmitate were 0.13 mmol/L and 60.6 mmol/(L·min), respectively. The results show that this novel lipase has potential industrial applications.

Key words

alkaline lipaseAspergillus awamoripurificationcharacterization

Copyright information

© Central South University Press and Springer-Verlag Berlin Heidelberg 2011

Authors and Affiliations

  • Jin-lan Xia (夏金兰)
    • 1
  • Bin Huang (黄斌)
    • 1
  • Zhen-yuan Nie (聂珍媛)
    • 1
  • Wei Wang (王威)
    • 1
  1. 1.School of Minerals Processing and BioengineeringCentral South UniversityChangshaChina