Browsing by Keyword "Acetoin"
Now showing 1 - 2 of 2
Results Per Page
Sort Options
Item Efficient production of acetoin by fermentation using the newly isolated mutant strain Lactococcus lactis subsp. lactis CML B4(2017-07) Roncal, Tomás; Caballero, Susana; Díaz de Guereñu, María del Mar; Rincón, Inés; Prieto-Fernández, Soraya; Ochoa-Gómez, Jose R.; Tecnalia Research & Innovation; BIOECONOMÍA Y CO2; TECNOLOGÍA DE MEMBRANAS E INTENSIFICACIÓN DE PROCESOS; TECNOLOGÍAS DE HIDRÓGENO; GENERALWith the aim of applying biotechnology to produce acetoin, a chemical that can be used as an aroma and as a building block for other compounds, several putative mutants with reduced lactic acid synthesis were obtained from a wild-type homolactic strain of L. lactis subjected to chemical mutagenesis. Among these mutants, a strain was isolated, CML B4, that showed reduced lactate dehydrogenase (LDH) and increased NADH oxidase (NOX) activities. Shaken flask cultures of this mutant strain mainly produced acetoin, increasing the levels produced compared to the wild-type strain by 15-fold. A point mutation detected in the ldh gene encoding LDH was probably the genetic defect responsible for this phenotype. In pH-controlled aerobic batch fermentation, the CML B4 strain produced more than 40 gL−1 acetoin, which was increased by up to 59 gL−1 in fed-batch fermentations, with yields close to 88 and 74%, respectively, and productivities exceeding 2 gL−1 h−1. These results indicate that this strain could be used industrially as a cell factory for the production of acetoin from bioresources.Item Electrosynthesis of 2,3-butanediol and methyl ethyl ketone from acetoin in flow cells(2019) Ochoa-Gómez, José R.; Fernández-Carretero, Francisco; Río-Pérez, Francisca; García-Luis, Alberto; Roncal, Tomás; García-Suárez, Eduardo J.; Tecnalia Research & Innovation; TECNOLOGÍAS DE HIDRÓGENO; BIOECONOMÍA Y CO2Acetoin could shortly become a platform molecule due to current progress in fermentation technology, the megatrend for shifting from an oil-based economy to one based on biomass, the quest for green manufacturing processes and its two highly reactive carbonyl and hydroxyl moieties. In this paper, the successful electro-conversion of acetoin into two valuable chemicals, 2,3-butandiol (2,3-BD) and methyl ethyl ketone (MEK), at constant electrical current in aqueous phase at room temperature using both divided and undivided 20 cm2 filter-press flow cells under experimental conditions suitable for industrial production is reported. Cathode material is the key parameter to drive the electroreduction towards one or another chemical. 2,3-BD is the major chemical produced by electrohydrogenation when low hydrogen overvoltage cathodes, such as Pt and Ni, of high surface area obtained by PVD coating on a carbon gas diffusion layer are used, while MEK is the principal product produced by electrohydrogenolysis when high hydrogen overvoltage cathodes, such as graphite, Pb and Cd foils, are employed. 2,3-BD and MEK can be obtained, respectively, in 92.8% and 85.7% selectivities, 71.7% and 80.4% current efficiencies, with 1.21 and 1.08 kg.h-1.m-2 productivities and power consumptions of 2.94 and 4.1 kWh.kg-1 using undivided cells and aqueous K2HPO4 electrolysis media at pHs of 3.6 and 5.5. The reported electroconversion of acetoin is highly flexible because 2,3-BD and MEK can be produced by changing just the cathode but using the same cell, with the same electrolyte at the same current density.