title: In situ enrichment of folate by microorganisms in beta-glucan rich oat and barley matrices.
abstract: The objective was to study folate production of yeast strains, bacteria isolated from oat bran, and selected lactic acid bacteria as well as one propionibacterium in oat and barley based models. Simultaneously, we aimed at sustaining the stability of viscosity, representing the physicochemical state of beta-glucan. Total folate contents were determined microbiologically and vitamers for selected samples by UHPLC. Folate in yeast cells comprised mainly 5-methyltetrahydrofolate and tetrahydrofolate. Folate production by microbes in YPD medium was different to that in cereal fermentations where vitamers included 5-methyltetrahydrofolate, 5,10-methenyltetrahydrofolate and formylated derivatives. Microbes producing significant amounts of folate without affecting viscosity were Saccharomyces cerevisiae ALKO743 and Candida milleri ABM4949 among yeasts and Pseudomonas sp. ON8 and Janthinobacterium sp. RB4 among bacteria. Net folate production was up to 120 ng/g after 24 h fermentation and could increase during 2-week storage. Glucose addition increased the proportion of 5-methyltetrahydrofolate. Streptococcus thermophilus ABM5097, Lactobacillus reuteri, and Propionibacterium sp. ABM5378 produced folate but in lower concentrations. Both endogenous and added microbes contribute to folate enhancement. Selection of microbes with folate producing capability and limited hydrolytic activity will enable the development of products rich in folate and beta-glucan.
authors.affiliation: Department of Food and Environmental Sciences, University of Helsinki, P.O. Box 27, FIN-00014, Finland. Electronic address: susanna.kariluoto@helsinki.fi.
authors.forename: Susanna
authors.initials: S
authors.lastname: Kariluoto
authors.affiliation: Department of Food and Environmental Sciences, University of Helsinki, P.O. Box 27, FIN-00014, Finland.
authors.forename: Minnamari
authors.initials: M
authors.lastname: Edelmann
authors.affiliation: Department of Food and Environmental Sciences, University of Helsinki, P.O. Box 27, FIN-00014, Finland.
authors.forename: Laura
authors.initials: L
authors.lastname: Nyström
authors.affiliation: Department of Food and Environmental Sciences, University of Helsinki, P.O. Box 27, FIN-00014, Finland.
authors.forename: Tuula
authors.initials: T
authors.lastname: Sontag-Strohm
authors.affiliation: Department of Food and Environmental Sciences, University of Helsinki, P.O. Box 27, FIN-00014, Finland.
authors.forename: Hannu
authors.initials: H
authors.lastname: Salovaara
authors.affiliation: Department of Food and Environmental Sciences, University of Helsinki, P.O. Box 27, FIN-00014, Finland.
authors.forename: Reetta
authors.initials: R
authors.lastname: Kivelä
authors.affiliation: Department of Biological Sciences, University of Helsinki, P.O. Box 56, FIN-00014, Finland.
authors.forename: Mirkka
authors.initials: M
authors.lastname: Herranen
authors.affiliation: Department of Biological Sciences, University of Helsinki, P.O. Box 56, FIN-00014, Finland.
authors.forename: Matti
authors.initials: M
authors.lastname: Korhola
authors.affiliation: Department of Food and Environmental Sciences, University of Helsinki, P.O. Box 27, FIN-00014, Finland.
authors.forename: Vieno
authors.initials: V
authors.lastname: Piironen
mesh_terms: D018554:Avena / Q000382:microbiology*; D005285:Fermentation; D005492:Folic Acid / Q000032:analysis / Q000096:biosynthesis*; D005516:Food Microbiology; D001467:Hordeum / Q000382:microbiology*; D014783:Viscosity; D015003:Yeasts / Q000201:enzymology / Q000378:metabolism*; D047071:beta-Glucans
chemical_list: D047071:beta-Glucans; C067858:beta-glucan, (1-3)(1-4)-; D005492:Folic Acid
keywords: Barley; Beta-glucan; Fermentation; Folate; Oat; Viscosity