title: Enzymatic production of a solvent-free menthyl butyrate via response surface methodology catalyzed by a novel thermostable lipase fromGeobacillus zalihae.
abstract: Most substrate for esterification has the inherent problem of low miscibility which requires addition of solvents into the reaction media. In this contribution, we would like to present an alternative and feasible option for an efficient solvent-free synthesis of menthyl butyrate using a novel thermostable crude T1 lipase. We investigated the effects of incubation time, temperature, enzyme loading and substrate molar ratio and determined the optimum conditions. The high conversion of menthyl butyrate catalyzed by crude T1 lipase in a solvent-free system is greatly affected by temperature and time of the reaction media. The highest yield of menthyl butyrate was 99.3% under optimized conditions of 60 °C, incubation time of 13.15 h, 2.53 mg, 0.43% (w/w) enzyme to substrate ratio and at molar ratio of butyric anhydride/menthol 2.7:1. Hence, the investigation revealed that the thermostable crude T1 lipase successfully catalyzed the high-yield production of menthyl butyrate in a solvent-free system. The finding suggests that the crude T1 lipase was a promising alternative to overcome shortcomings associated with solvent-assisted enzymatic reactions.
authors.affiliation: Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia , 81310 Skudai , Johor , Malaysia.
authors.forename: Roswanira Abdul
authors.initials: RA
authors.lastname: Wahab
authors.affiliation: Department of Chemistry, Faculty of Science, Universiti Putra Malaysia, 43400Serdang, Selangor, Malaysia; Institute of Bioscience, Universiti Putra Malaysia, 43400UPM Serdang, Selangor, Malaysia; Enzyme and Microbial Technology Research Centre, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
authors.forename: Mahiran
authors.initials: M
authors.lastname: Basri
authors.affiliation: Institute of Bioscience, Universiti Putra Malaysia, 43400UPM Serdang, Selangor, Malaysia; Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400Serdang, Selangor, Malaysia; Enzyme and Microbial Technology Research Centre, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
authors.forename: Raja Noor Zaliha Raja Abdul
authors.initials: RN
authors.lastname: Rahman
authors.affiliation: Institute of Bioscience, Universiti Putra Malaysia, 43400UPM Serdang, Selangor, Malaysia; Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400Serdang, Selangor, Malaysia.
authors.forename: Abu Bakar
authors.initials: AB
authors.lastname: Salleh
authors.affiliation: Department of Chemistry, Faculty of Science, Universiti Putra Malaysia, 43400Serdang, Selangor, Malaysia; Enzyme and Microbial Technology Research Centre, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
authors.forename: Mohd Basyaruddin Abdul
authors.initials: MB
authors.lastname: Rahman
authors.affiliation: Department of Chemistry, Faculty of Science, University of Guilan , Rasht , Iran.
authors.forename: Naz
authors.initials: N
authors.lastname: Chaibakhsh
authors.affiliation: Institute of Bioscience, Universiti Putra Malaysia, 43400UPM Serdang, Selangor, Malaysia; Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400Serdang, Selangor, Malaysia; Enzyme and Microbial Technology Research Centre, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
authors.forename: Thean Chor
authors.initials: TC
authors.lastname: Leow
keywords: Geobacillus zalihae; T1 lipase; central composite rotatable design; esterification