title: Enzymatic synthesis of eugenol benzoate by immobilized Staphylococcus aureus lipase: optimization using response surface methodology and determination of antioxidant activity.
abstract: The ability of a non-commercial immobilized Staphylococcus aureus lipase to catalyze the esterification of eugenol with benzoic acid was checked and the antioxidant power of the ester formed was evaluated. Response surface methodology based on four variables (the reaction temperature, the amount of lipase, the benzoic acid/eugenol molar ratio and the volume of solvent) was used to optimize the experimental conditions of eugenol benzoate synthesis. The maximum conversion yield (75%) was obtained using 240 IU of immobilized lipase, a benzoic acid/eugenol molar ratio of 1.22 dissolved in 4.6 ml chloroform at 41 degrees Celsius. The antioxidant activities of eugenol and its ester were evaluated. Compared to BHT, used as a model synthetic antioxidant, the eugenol benzoate showed a higher antioxidative activity. The IC(50) value for 1,1-diphenyl-2-picrylhydrazyl was found to be 18.2 microg/ml versus 20.2 microg/ml for eugenol and eugenol benzoate.
authors.affiliation: Laboratoire de Biochimie et de Génie Enzymatique des Lipases, ENIS, BPW, 1173 Sfax, Tunisia.
authors.forename: Habib
authors.initials: H
authors.lastname: Horchani
authors.forename: Nadia
authors.initials: N
authors.lastname: Ben Salem
authors.forename: Zied
authors.initials: Z
authors.lastname: Zarai
authors.forename: Adel
authors.initials: A
authors.lastname: Sayari
authors.forename: Youssef
authors.initials: Y
authors.lastname: Gargouri
authors.forename: Moncef
authors.initials: M
authors.lastname: Chaâbouni
mesh_terms: D000975:Antioxidants / Q000378:metabolism; D001565:Benzoates / Q000378:metabolism*; D004951:Esterification; D005054:Eugenol / Q000378:metabolism*; D008401:Gas Chromatography-Mass Spectrometry; D008049:Lipase / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D013211:Staphylococcus aureus / Q000201:enzymology*; D013696:Temperature
chemical_list: D000975:Antioxidants; D001565:Benzoates; D005054:Eugenol; D008049:Lipase