title: Improved 1,3-Propanediol Synthesis from Glycerol by the Robust Lactobacillus reuteri Strain DSM 20016.
abstract: Various Lactobacillus reuteri strains were screened for the ability to convert glycerol to 1,3- propanediol (1,3-PDO) in a glycerol-glucose co-fermentation. Only L. reuteri DSM 20016, a well-known probiotic, was able to efficiently carry out this bioconversion. Several process strategies were employed to improve this process. CO(2+) addition to the fermentation medium, led to a high product titer (46 g/l) of 1,3-PDO and to improved biomass synthesis. L. reuteri DSM 20016 produced also ca. 3 μg/g of cell dry weight of vitamin B12, conferring an economic value to the biomass produced in the process. Incidentally, we found that L. reuteri displays the highest resistance to CO(2+) ions ever reported for a microorganism. Two waste materials (crude glycerol from biodiesel industry and spruce hydrolysate from paper industry) alone or in combination were used as feedstocks for the production of 1,3-PDO by L. reuteri DSM 20016. Crude glycerol was efficiently converted into 1,3-PDO although with a lower titer than pure glycerol (-18%). Compared with the fermentation carried out with pure substrates, the 1,3- PDO produced was significantly lower (40.7 vs. 24.2 g/l) using cellulosic hydrolysate and crude glycerol, but strong increases of the maximal biomass produced (+27%) and of the glucose consumption rate (+46%) were found. The results of this study lay the foundation for further investigations to exploit the biotechnological potential of L. reuteri DSM 20016 to produce 1,3-PDO and vitamin B12 using industry byproducts.
authors.affiliation: Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, 70125 Bari, Italy.|CIRCC - Interuniversity Consortium Chemical Reactivity and Catalysis, 70126 Bari, Italy.
authors.forename: Maria Antonietta
authors.initials: MA
authors.lastname: Ricci
authors.affiliation: Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, 70125 Bari, Italy.|CIRCC - Interuniversity Consortium Chemical Reactivity and Catalysis, 70126 Bari, Italy.
authors.forename: Annamaria
authors.initials: A
authors.lastname: Russo
authors.affiliation: Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, 70125 Bari, Italy.|CIRCC - Interuniversity Consortium Chemical Reactivity and Catalysis, 70126 Bari, Italy.
authors.forename: Isabella
authors.initials: I
authors.lastname: Pisano
authors.affiliation: Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, 70125 Bari, Italy.|CIRCC - Interuniversity Consortium Chemical Reactivity and Catalysis, 70126 Bari, Italy.|CNR Institute of Biomembranes and Bioenergetics (IBBE), 70126, Bari, Italy.
authors.forename: Luigi
authors.initials: L
authors.lastname: Palmieri
authors.affiliation: Department of Soil, Plant and Food Science, University of Bari Aldo Moro, 70126 Bari, Italy.
authors.forename: Maria
authors.initials: M
authors.lastname: de Angelis
authors.affiliation: Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, 70125 Bari, Italy.|CIRCC - Interuniversity Consortium Chemical Reactivity and Catalysis, 70126 Bari, Italy.
authors.forename: Gennaro
authors.initials: G
authors.lastname: Agrimi
mesh_terms: D002413:Cations, Divalent / Q000378:metabolism; D003035:Cobalt / Q000378:metabolism; D005285:Fermentation; D005947:Glucose / Q000378:metabolism; D005990:Glycerol / Q000378:metabolism*; D007220:Industrial Waste; D052200:Limosilactobacillus reuteri / Q000378:metabolism*; D011409:Propylene Glycols / Q000378:metabolism*; D014805:Vitamin B 12 / Q000378:metabolism; D014865:Waste Disposal, Fluid / Q000379:methods
chemical_list: D002413:Cations, Divalent; D007220:Industrial Waste; D011409:Propylene Glycols; D003035:Cobalt; C041787:1,3-propanediol; D005947:Glucose; D014805:Vitamin B 12; D005990:Glycerol