Anaerobic degradation of sorbic acid by sulfate-reducing and fermenting bacteria: pentanone-2 and isopentanone-2 as byproducts

Abstract

Strictly anaerobic bacteria were enriched and isolated from freshwater sediment sources in the presence and absence of sulfate with sorbic acid as sole source of carbon and energy. Strain WoSol, a Gram-negative vibrioid sulfate-reducing bacterium which was assigned to the species Desulfoarculus (formerly Desulfovibrio) baarsii oxidized sorbic acid completely to CO2 with concomitant stoichiometric reduction of sulfate to sulfide. This strain also oxidized a wide variety of fatty acids and other organic compounds. A Gram-negative rod-shaped fermenting bacterium, strain AmSol, fermented sorbic acid stoichiometrically to about equal amounts of acetate and butyrate. At concentrations higher than 10 mM, sorbic acid fermentation led to the production of pentanone-2 and isopentanone-2 (3-methyl-2-butanone) as byproducts. Strain AmSol fermented also crotonate and 3-hydroxybutyrate to acetate and butyrate, and hexoses to acetate, ethanol, hydrogen, and formate. The guanine-plus-cytosine content of the DNA was 41.8 + 1.0 mol%. Sorbic acid at concentrations higher than 5 mM inhibited growth of this strain while strain WoSol tolerated sorbic acid up to 10 mM concentration.

Microbial succession during the degradation of bioplastic in coastal marine sediment favors sulfate reducing microorganisms

“…Desulfoarculaceae is also underrepresented in the literature, with only five described genera and eight r e p r e s e n t a t i v e g e n o m e s i n N C B I . I s o l a t e s f r o m Desulfarculaceae are strictly anaerobic (Kuever, 2014) and capable of degrading a variety of complex carbon sources including pyruvate (Davidova et al, 2016), benzoate (An and Picardal, 2014), sorbate (Schnell et al, 1991), and 3hydroxybutyrate (Schnell et al, 1991), the latter of which is the building block of common PHAs. This suggests that members of Desulfarulaceae may be utilizing PHA as a carbon source and their enrichment during the later stages of the experiment could have been facilitated by substrate pitting and the creation of anoxic microenvironments.…”

Synthesis and Characterization of Ferric Sorbate and Aluminum Sorbate as Antifouling Pigments for Marine Paints

“…Potassium sorbate is a salt of ( E , E )-2,4-hexadienoic acid that is used widely as a food preservative to inhibit the growth of bacteria, mold, yeasts, and fungi (Figure ). This compound is a cheap and biodegradable commercial chemical classified as “generally regarded as safe” by the U.S. Food and Drug Administration. , Potassium sorbate showed good antisettlement activity at concentrations that were not acutely toxic to barnacle larvae (therapeutic ratio = 3.71), and the effect was reversible, demonstrating that the compound acts via a nontoxic mechanism …”

“…This compound is a cheap and biodegradable commercial chemical classified as "generally regarded as safe" by the U.S. Food and Drug Administration. 19,20 Potassium sorbate showed good antisettlement activity at concentrations that were not acutely toxic to barnacle larvae (therapeutic ratio = 3.71), and the effect was reversible, demonstrating that the compound acts via a nontoxic mechanism. 15 Potassium sorbate is highly soluble in water.…”

The Flavouring Phytochemical 2-Pentanone Reduces Prostaglandin Production and COX-2 Expression in Colon Cancer Cells

“…40,41) In addition, anaeorbic bacteria isolated from fresh water sediment can produce 2-pentanone as a byproduct of sorbic acid degradation. 42) Furthermore, 2-pentanone has been identified as a volatile fragment from cholesterol autoxidation and as one of many volatile compounds de- 43,44) Taken together there is major evidence that 2-pentanone is frequently occurring in food of different kinds and hence we were interested in investigating the potential anti-inflammatory effects of this compound. The aim with the present study was to investigate whether the flavouring compound 2-pentanone exhibits any COX-2 inhibitory effects in vitro.…”