Medium-based optimization of an organic solvent-tolerant extracellular lipase from the isolated halophilic Alkalibacillus salilacus

Extremophiles. 2015 Sep;19(5):933-47. doi: 10.1007/s00792-015-0769-7. Epub 2015 Jul 22.

Abstract

A haloalkaliphilic solvent-tolerant lipase was produced from Alkalibacillus salilacus within 48 h of growth in liquid medium. An overall 4.9-fold enhanced production was achieved over unoptimized media after medium optimization by statistical approaches. Plackett-Burman screening suggested lipase production maximally influenced by olive oil, KH2PO4, NaCl, and glucose; and response surface methodology predicted the appropriate levels of each parameter. Produced lipase was highly active and stable over broad ranges of temperature (15-65 °C), pH (4.0-11.0), and NaCl concentration (0-30 %) showing excellent thermostable, pH-stable, and halophilic properties. The enzyme was optimally active at pH 8.0 and 40 °C. Majority of cations, except some like Co(2+) and Al(3+) were positive signals for lipase activity. In addition, the presence of chemical agents and organic solvents with different log P ow was well tolerated by the enzyme. Finally, efficacy of lipase-mediated esterification of various alcohols with oleic acid in organic solvents was studied.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alcohols / chemistry
  • Aluminum / chemistry
  • Bacillaceae / enzymology*
  • Bacterial Proteins / chemistry*
  • Bacterial Proteins / metabolism
  • Cobalt / chemistry
  • Enzyme Stability
  • Fatty Acids / chemistry
  • Lipase / chemistry*
  • Lipase / metabolism
  • Nitrophenols / chemistry
  • Salt Tolerance*
  • Substrate Specificity

Substances

  • Alcohols
  • Bacterial Proteins
  • Fatty Acids
  • Nitrophenols
  • Cobalt
  • Aluminum
  • Lipase