title: Solvent-free lipase-catalyzed synthesis of a novel hydroxyl-fatty acid derivative of kojic acid.
abstract: The aim of this work was the synthesis of a novel hydroxyl-fatty acid derivative of kojic acid rich in kojic acid monoricinoleate (KMR) which can be widely used in the cosmetic and food industry. The synthesis of KMR was carried out by lipase-catalysed esterification of ricinoleic and kojic acids in solvent-free system. Three immobilized lipases were tested and the best KMR yields were attained with Lipozyme TL IM and Novozym 435. Since Lipozyme TL IM is the cheapest, it was selected to optimize the reaction conditions. The optimal reaction conditions were 80 °C for the temperature, 1:1 for the alcohol/acid molar ratio, 600 rpm for stirring speed and 7.8% for the catalyst concentration. Under these conditions, the reaction was scaled up in a 5×10⁻³ m³ stirred tank reactor. ¹H-¹³C HMBC-NMR showed that the primary hydroxyl group of kojic acid was regioselectively esterified. The KMR has more lipophilicity than kojic acid and showed antioxidant activity that improves the oxidation stability of biodiesel.
authors.affiliation: Department of Chemical Engineering, Faculty of Chemistry, University of Complutense, 28040 Madrid, Spain.
authors.forename: Noureddin
authors.initials: N
authors.lastname: El-Boulifi
authors.affiliation: Department of Bioprocess Technology, Faculty of Biotechnology and Biomolecular Sciences, University Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
authors.forename: Siti Efliza
authors.initials: SE
authors.lastname: Ashari
authors.affiliation: Department of Chemical Engineering, Faculty of Chemistry, University of Complutense, 28040 Madrid, Spain.
authors.forename: Marta
authors.initials: M
authors.lastname: Serrano
authors.affiliation: Department of Chemical Engineering, Faculty of Chemistry, University of Complutense, 28040 Madrid, Spain.
authors.forename: Jose
authors.initials: J
authors.lastname: Aracil
authors.affiliation: Department of Chemical Engineering, Faculty of Chemistry, University of Complutense, 28040 Madrid, Spain. Electronic address: mmr1@quim.ucm.es.
authors.forename: Mercedes
authors.initials: M
authors.lastname: Martínez
mesh_terms: D000975:Antioxidants / Q000494:pharmacology; D055162:Biocatalysis; D056804:Biofuels; D002175:Candida / Q000201:enzymology; D004355:Drug Stability; D004800:Enzymes, Immobilized; D004951:Esterification; D032641:Eurotiales / Q000201:enzymology; D005229:Fatty Acids, Monounsaturated; D005656:Fungal Proteins / Q000378:metabolism; D008049:Lipase / Q000378:metabolism*; D010938:Plant Oils; D011753:Pyrones / Q000032:analysis* / Q000737:chemistry / Q000378:metabolism; D000074262:Rapeseed Oil; D020103:Rhizomucor / Q000201:enzymology; D012277:Ricinoleic Acids / Q000378:metabolism*; D012995:Solubility; D012997:Solvents; D013696:Temperature
chemical_list: D000975:Antioxidants; D056804:Biofuels; D004800:Enzymes, Immobilized; D005229:Fatty Acids, Monounsaturated; D005656:Fungal Proteins; D010938:Plant Oils; D011753:Pyrones; D000074262:Rapeseed Oil; D012277:Ricinoleic Acids; D012997:Solvents; C011890:kojic acid; C093666:Lipozyme; C093667:Novozyme 435; D008049:Lipase; C030521:ricinoleic acid
keywords: Esterification; Hydroxyl-fatty acid; Kojic acid; Lipase; Optimization; Solvent-free system