title: Antimicrobial and antioxidant activities of clove essential oil and eugenyl acetate produced by enzymatic esterification.
abstract: This work reports the maximization of eugenyl acetate production by esterification of essential oil of clove in a solvent-free system using Novozym 435 as catalyst. The antimicrobial and antioxidant activities of clove essential oil and eugenyl acetate produced were determined. The conditions that maximized eugenyl acetate production were 60 °C, essential oil of clove to acetic anhydride ratio of 1:5, 150 rpm, and 10 wt% of enzyme, with a conversion of 99.87 %. A kinetic study was performed to assess the influence of substrates' molar ratio, enzyme concentration, and temperature on product yield. Results show that an excess of anhydride, enzyme concentration of 5.5 wt%, 50 °C, and essential oil of clove to acetic anhydride ratio of 1:5 afforded nearly a complete conversion after 2 h of reaction. Comparing the antibacterial activity of the essential oil of clove before and after esterification, we observed a decrease in the antimicrobial activity of eugenyl acetate, particularly with regard to minimum inhibitory concentration (MIC). Both eugenyl acetate and clove essential oil were most effective to the gram-negative than gram-positive bacteria group. The results showed a high antioxidant potential for essential oil before and particularly after the esterification reaction thus becoming an option for the formulation of new antioxidant products.
authors.affiliation: Department of Food Engineering, URI-Campus de Erechim, Av. Sete de Setembro, 1621, Erechim, RS, 99700-000, Brazil.
authors.forename: Adriana B
authors.initials: AB
authors.lastname: Vanin
authors.affiliation: Department of Food Engineering, URI-Campus de Erechim, Av. Sete de Setembro, 1621, Erechim, RS, 99700-000, Brazil.
authors.forename: Tainara
authors.initials: T
authors.lastname: Orlando
authors.affiliation: Department of Food Engineering, URI-Campus de Erechim, Av. Sete de Setembro, 1621, Erechim, RS, 99700-000, Brazil.
authors.forename: Suelen P
authors.initials: SP
authors.lastname: Piazza
authors.affiliation: Department of Food Engineering, URI-Campus de Erechim, Av. Sete de Setembro, 1621, Erechim, RS, 99700-000, Brazil.
authors.forename: Bruna M S
authors.initials: BMS
authors.lastname: Puton
authors.affiliation: Department of Food Engineering, URI-Campus de Erechim, Av. Sete de Setembro, 1621, Erechim, RS, 99700-000, Brazil.
authors.forename: Rogério L
authors.initials: RL
authors.lastname: Cansian
authors.affiliation: Department of Chemical and Food Engineering, Universidade Federal de Santa Catarina, UFSC, Campus Universitário, Bairro Trindade, Caixa Postal 476, Florianópolis, SC, 88040-900, Brazil. odebora@uricer.edu.br.
authors.forename: Debora
authors.initials: D
authors.lastname: Oliveira
authors.affiliation: Department of Food Engineering, URI-Campus de Erechim, Av. Sete de Setembro, 1621, Erechim, RS, 99700-000, Brazil.
authors.forename: Natalia
authors.initials: N
authors.lastname: Paroul
mesh_terms: D000890:Anti-Infective Agents / Q000737:chemistry*; D000975:Antioxidants / Q000737:chemistry*; D045783:Clove Oil / Q000737:chemistry*; D004800:Enzymes, Immobilized; D005054:Eugenol / Q000737:chemistry; D005656:Fungal Proteins; D007700:Kinetics; D008049:Lipase / Q000737:chemistry*; D009822:Oils, Volatile / Q000737:chemistry*; D027842:Syzygium / Q000737:chemistry*
chemical_list: D000890:Anti-Infective Agents; D000975:Antioxidants; D045783:Clove Oil; D004800:Enzymes, Immobilized; D005656:Fungal Proteins; D009822:Oils, Volatile; D005054:Eugenol; C093667:Novozyme 435; D008049:Lipase