food and bioproducts processing 1 0 2 ( 2 0 1 7 ) 153–166 Contents lists available at ScienceDirect Food and Bioproducts Processing j ourna l ho me page: www.elsevier.com/locate/fbp Production of the renewable extremophile lipase: Valuable biocatalyst with potential usage in food industry Mina Memarpoor-Yazdi a , Hamid Reza Karbalaei-Heidari a,∗ , Khosro Khajeh b a Molecular Biotechnology Laboratory, Department of Biology, Faculty of Science, Shiraz University, Shiraz 71454, Iran b Enzymology Laboratory, Department of Biochemistry, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran a r t i c l e i n f o Article history: Received 6 October 2016 Received in revised form 10 December 2016 Accepted 27 December 2016 Available online 3 January 2017 Keywords: Biocatalysts Lipase Immobilization Chitosan coated magnetite nanoparticles Food industry Methyl acetate a b s t r a c t In the food industry, biocatalysts provide ecofriendly procedures to accomplish biochemical reactions with high specificity in moderate conditions. In this regard, enzymes are wel- comed as process aids in food processing. Microbial lipases, especially of extremophiles, are one of the most useful enzymes for biotechnology and food industry. Accordingly, thermo-halophile GDSL lipase-encoding gene from Rhodothermus marinus, RD, was cloned and expressed in Escherichia coli. The enzyme revealed the highest hydrolytic activity (1055.3 Umg −1 ) towards p-nitrophenyl butyrate (C4) at 70 ◦ C/pH 8.5 and retained 78.6% of its initial activity after 60 min incubation at this temperature. The enzyme was recovered by covalent immobilization on chitosan coated Fe 3 O 4 -nanoparticles (CS-MNPs) and the poten- tial to synthesize aroma ester methyl acetate in n-hexane was investigated. The reaction yields were 22% and 67% for free and immobilized enzyme, respectively. This study provides a time-saving, economic, biocompatible and a renewable catalyst to synthesize natural fla- vor compounds. This biocatalyst has excellent potential in food industry and can be applied for lipid processing or to improve the aroma of foods. In addition to exhibiting good stability in high temperatures and organic solvents, RD lipase from Rhodothermus marinus can also be considered as an excellent candidate in organic synthesis in harsh industry conditions. © 2016 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved. 1. Introduction Biocatalysts provide clean, ecological and specific procedures to ful- fill biochemical reactions under moderate conditions (Ferreira-Dias et al., 2013). Lipases are excellent catalysts that perform bioconver- sions to produce food additives and ingredients (Barros et al., 2010). They revealed great potential to synthesize short chain esters usable in food industry as flavor modifiers or fragrance compounds (Ferreira-Dias et al., 2013). In the dairy industry, lipases play critical role to hydrolyze milk fat, enhance cheese flavor, accelerate cheese ripening, and ∗ Corresponding author at: Molecular Biotechnology Lab Department of Biology, Faculty of Sciences, Shiraz University, P.O. Box: 71467- 13565, Shiraz 71454, Iran. Fax: +98 71 32280926. E-mail addresses: karbalaei@shirazu.ac.ir, karbalaei76@gmail.com (H.R. Karbalaei-Heidari). lipolysis of butterfat. The addition of lipases leads to release of short chain fatty acids (C4 and C6), which enhances a sharp tangy flavor, while the release of medium chain fatty acids (C12 and C14) gives a soapy taste to the product (Fox, 1993; Gupta et al., 2003). In the lipid industry, lipases can be utilized for retailoring of animal and vegetable oils (Ferreira-Dias et al., 2013). A new subclass of lipolytic enzymes belonging to the GDSL family have attracted attention due to multifunctional properties such as a wide substrate specificity and regioselectivity (Akoh et al., 2004). This family possesses a flexible active site that undergoes conformational http://dx.doi.org/10.1016/j.fbp.2016.12.015 0960-3085/© 2016 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.