Vanillin production from ferulic acid with Pseudomonas fluorescens BF13-1p4

Dal Bello, Elena (2013) Vanillin production from ferulic acid with Pseudomonas fluorescens BF13-1p4 , [Dissertation thesis], Alma Mater Studiorum Università di Bologna. Dottorato di ricerca in Biologia cellulare, molecolare e industriale/cellular, molecular and industrial biology: progetto n. 3 Microbiologia e biotecnologie industriali, 25 Ciclo. DOI 10.6092/unibo/amsdottorato/5482.
Documenti full-text disponibili:
Documento PDF (English) - Richiede un lettore di PDF come Xpdf o Adobe Acrobat Reader
Download (2MB) | Anteprima


Bioconversion of ferulic acid to vanillin represents an attractive opportunity for replacing synthetic vanillin with a bio-based product, that can be label “natural”, according to current food regulations. Ferulic acid is an abundant phenolic compound in cereals processing by-products, such as wheat bran, where it is linked to the cell wall constituents. In this work, the possibility of producing vanillin from ferulic acid released enzymatically from wheat bran was investigated by using resting cells of Pseudomonas fluorescens strain BF13-1p4 carrying an insertional inactivation of vdh gene and ech and fcs BF13 genes on a low copy number plasmid. Process parameters were optimized both for the biomass production phase and the bioconversion phase using food-grade ferulic acid as substrate and the approach of changing one variable while fixing the others at a certain level followed by the response surface methodology (RSM). Under optimized conditions, vanillin up to 8.46 mM (1.4 g/L) was achieved, whereas highest productivity was 0.53 mmoles vanillin L-1 h-1). Cocktails of a number of commercial enzyme (amylases, xylanases, proteases, feruloyl esterases) combined with bran pre-treatment with steam explosion and instant controlled pressure drop technology were then tested for the release of ferulic acid from wheat bran. The highest ferulic acid release was limited to 15-20 % of the ferulic acid occurring in bran, depending on the treatment conditions. Ferulic acid 1 mM in enzymatic hydrolyzates could be bioconverted into vanillin with molar yield (55.1%) and selectivity (68%) comparable to those obtained with food-grade ferulic acid after purification from reducing sugars with a non polar adsorption resin. Further improvement of ferulic acid recovery from wheat bran is however required to make more attractive the production of natural vanillin from this by-product.

Tipologia del documento
Tesi di dottorato
Dal Bello, Elena
Dottorato di ricerca
Scuola di dottorato
Scienze biologiche, biomediche e biotecnologiche
Settore disciplinare
Settore concorsuale
Parole chiave
Biovanillin, ferulic acid, Pseudomonas, bioconversion, wheat bran, agro-industrial by-products
Data di discussione
17 Maggio 2013

Altri metadati

Statistica sui download

Gestione del documento: Visualizza la tesi