VIEW ARTICLE    doi:10.1094/ASBCJ-2009-0915-01

Purification and Characteristics of Feruloyl Decarboxylase Produced by Lactic Acid Bacteria from Awamori Mash. Sayaka Watanabe (1), Department of Fermentation, Tokyo University of Agriculture, Tokyo, Japan; Makoto Kanauchi, Department of Food Management, Miyagi University, Sendai, Japan; and Kojiro Takahashi and Takeo Koizumi, Department of Fermentation, Tokyo University of Agriculture, Tokyo, Japan. (1) Corresponding author. E-mail: <60070001@nodai.ac.jp> J. Am. Soc. Brew. Chem. 67(4):229-234, 2009.

Despite serving important roles in the production of vanilla aroma, lactic acid bacteria are regarded as contaminants in spirit mash. We isolated the lactic acid bacteria that convert ferulic acid to 4-vinyl guaiacol (4-VG), purified their reactive enzyme, and examined their characteristics. The study showed that bound carboxyl was converted to carbon dioxide when ferulic acid was converted to 4-VG. The results demonstrated that pH was increased by this conversion and that the bromothymol blue contained in the ferulic acid changed from yellow to blue. Lactic acid bacteria producing high levels of ferulic acid decarboxylase (strain C18), identified as Lactobacillus paracasei, were isolated and selected from awamori mash. Chromatography was used to purify the ferulic acid decarboxylase, a C18-strain–produced monomer protein with a molecular mass of 47.9 kDa. Optimum conditions for production were pH 3 and 60°C. The rho-coumaric acid decarboxylase identified in this study differed from the products of other L. plantarum strains in that the optimum temperature was 30°C and the optimum pH was 5.5–6.0. Metal ions such as Cu(^2+) and Fe(^2+) activated the enzyme. Keywords: rho-Coumaric acid, Ferulic acid decarboxylase, Lactic acid bacteria, Lactobacillus paracasei, 4-Vinyl guaiacol

A pesar de que sirve un papel importante en la producción de aroma de vainilla, las bacterias del ácido láctico son consideradas como contaminantes en mosto espíritu. Se aislaron las bacterias del ácido láctico que convierten el ácido ferúlico a 4-vinilo guayacol (4-VG), purificadó la enzima reactiva, y examinó sus características. El estudio mostró que carboxilo unido se convierte en dióxido de carbono cuando el ácido ferúlico se convirtió en 4-VG. Los resultados demostraron que el pH se incrementó en esta conversión y que el azul de bromotimol contenidos en el ácido ferúlico cambiado de amarillo a azul. Las bacterias ácido lácticas producir altos niveles de la decarboxilasa del ácido ferúlico (C18 cepa), identificadas como Lactobacillus paracasei, fueron aislados y seleccionados del mosto awamori. Cromatografía se usa para purificar la decarboxilasa del ácido ferúlico, un C18-cepa-producida proteína monómero con un peso molecular de 47.9 kDa. Las condiciones óptimas para la producción fueron pH 3 y 60°C. El rho-decarboxilasa del ácido cumárico identificados en este estudio difiere de los productos de otras cepas de L. plantarum en que la temperatura óptima es de 30°C y el pH óptimo es 5.5–6.0. Los iones metálicos, tales como Cu(^2+) y Fe(^2+) activa la enzima. Palabras claves: Bacterias del ácido láctico, rho-Cumárico, Decarboxilasa del ácido ferúlico, Lactobacillus paracasei, 4-Vinilo guayacol