Bioreduction with immobilized bakers' yeast in hexane using alcohols as an energy source

Naoshima, Yoshinobu; Maeda, J.; Munakata, Y.; Nishiyama, T.; Kamezawa, Makoto; Tachibana, Hojun

doi:10.1039/c39900000964

Cited by 22 publications

(15 citation statements)

References 3 publications

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“…In this latter approach, as shown by Naoshima et al (19) for yeast, the organism is grown first under controlled conditions in an aqueous medium and then immobilized for later use as a biocatalyst in organic media. Even though the cells are not growing, they can remain viable during the course of reaction, thereby providing a means for regenerating depleted cofactors.…”

Section: Introductionmentioning

confidence: 99%

Asymmetric Ketone Reduction with Immobilized Yeast in Hexane: Biocatalyst Deactivation and Regeneration

Griffin

Gainer

Carta

2001

Biotechnology Progress

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There is a need to develop methods for producing enantiomerically pure pharmaceuticals because the racemic mixtures made today will probably not be allowed in the future. Synthetic chiral catalysts are being developed for this purpose, as well as new product separation techniques. Another possible option is to use biocatalysts, such as purified enzymes or whole microbial cells, since these can result in the production of mostly a single enantiomer. This study emphasizes the use of alginate-entrapped yeast cells to catalyze the reduction of ketones as a model system. The emphasis is on the factors that might limit the reactivity of such cells, such as equilibrium conditions, substrate or product inhibition, solvent toxicity, loss of cell viability, or the degradation of intracellular levels of enzymes or cofactors. It was found that there was a progressive loss of catalytic activity of the immobilized yeast cells, which appeared to be mainly associated with a loss of cell viability and a decline of intracellular NAD(H) levels during the reaction. The other factors investigated did not have a large effect. A regeneration scheme was developed in order to replenish the intracellular NAD(H) lost during the reaction, which involved removing the biocatalyst from the reaction and supplying the cells with a nutrient source. This resulted in an increase in the NAD(H) to initial levels and also resulted in a maintenance of the ketone reduction rate over time.

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Section: Introductionmentioning

confidence: 99%

Asymmetric Ketone Reduction with Immobilized Yeast in Hexane: Biocatalyst Deactivation and Regeneration

Griffin

Gainer

Carta

2001

Biotechnology Progress

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“…Por exemplo, pode-se citar a síntese realizada por Mori e Takikawa 11 da (3S,11R)-3,11-dimetil-2-nonacosanona (3), feromônio produzido pelas fêmeas da barata, Blattella germanica (Orthoptera: Blattellidae), ou da (5Z,13S)-5-tetradecen-13-olida (4), sinergista do feromônio de agregação dos besouros do grão, Cryptolestes pusillus (Coleoptera: Cucujidae) (Figura 3) 12 .…”

Section: Figura 1 Enantiômeros Do Sulcatol (1)unclassified

“…Uma mistura de (5S,9S)-5,9-dimetil-heptadecano (10a), principal componente do feromônio sexual do bicho mineiro do café, Leucoptera scitella (Lepidoptera: Lyonetiidae), e seu isômero (5R,9S)-11a foram sintetizados tendo como precursor o (R)-citronelal (12). Este foi obtido através de resolução cinética do citronelal racêmico com fermento de pão, que reduziu seletivamente o enantiômero S-12 levando ao álcool 13.…”

Section: Alcanosunclassified

O emprego de fermento de pão, Saccharomyces cerevisiae, na síntese de feromônios

Baraldi

Corrêa

2004

Quím. Nova

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“…Previous studies have examined the use of immobilized whole cells for biocatalysis in organic solvents (22,23). It has been observed that cell selectivity can be manipulated through the use of specific inhibitors, cell immobilization, and the choice of organic solvent (24)(25)(26).…”

Section: Introductionmentioning

confidence: 99%

Asymmetric Synthesis with Immobilized Yeast in Organic Solvents: Equilibrium Conversion and Effect of Reactant Partitioning on Whole Cell Biocatalysis

Gervais

Carta

Gainer

2003

Biotechnology Progress

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A newly isolated strain of the yeast Saccharomyces cerevisiae is investigated for the biocatalytic reduction of ketones and the oxidation of alcohols in organic solvents. The yeast cells are immobilized by entrapment within calcium alginate beads and are found to possess the ability to stereoselectively reduce prochiral ketones and oxidize chiral alcohols to equilibrium conversions. The effect of reactant partitioning on the initial rate of the reactions is also investigated. The observed initial rates are found to vary inversely with reactant partitioning between the organic solvent and the biocatalyst beads. A kinetic model is developed to describe the initial reaction rate of hexanone reduction as a function of substrate concentration within the alginate beads.

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Bioreduction with immobilized bakers' yeast in hexane using alcohols as an energy source

Cited by 22 publications

References 3 publications

Asymmetric Ketone Reduction with Immobilized Yeast in Hexane: Biocatalyst Deactivation and Regeneration

Asymmetric Ketone Reduction with Immobilized Yeast in Hexane: Biocatalyst Deactivation and Regeneration

O emprego de fermento de pão, Saccharomyces cerevisiae, na síntese de feromônios

Asymmetric Synthesis with Immobilized Yeast in Organic Solvents: Equilibrium Conversion and Effect of Reactant Partitioning on Whole Cell Biocatalysis

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