Enhancing xylose and glucose utilization as well as solvent production using a simplified three-electrode potentiostat s
- PDF / 876,154 Bytes
- 7 Pages / 595.276 x 790.866 pts Page_size
- 12 Downloads / 157 Views
ENVIRONMENTAL MICROBIOLOGY - ORIGINAL PAPER
Enhancing xylose and glucose utilization as well as solvent production using a simplified three‑electrode potentiostat system during Clostridium fermentation Jovan Popovic1 · Kevin T. Finneran2 Received: 14 August 2020 / Accepted: 17 September 2020 © Society for Industrial Microbiology and Biotechnology 2020
Abstract A simple potentiostat was constructed as a strategy to enhance solvent production in a mediatorless and oxygen-exposed fermentation inoculated with the aerotolerant strain Clostridium sp. C10. Elevated n-butanol and acetone titers were recorded in all fermentations with either glucose or xylose in the presence of electrodes poised at + 500 mV (+ 814 mV vs SHE) relative to cells plus substrate only controls. Respective butanol titers and volumetric butanol productivities in studies performed with 30 g/L glucose or 30 g/L xylose were 1.67 and 2.27 times and 1.90 and 6.13 times greater in the presence of electrodes compared to controls. Glucose and xylose utilization in the presence of electrodes was 61 and 125% greater than no-electrode controls, respectively. Increasing substrate concentrations to 60 g/L decreased the butanol yields relative to the studies performed at 30 g/L. These data suggest that it may be more efficient to alter reactor reduction potential than increase substrate concentration for solvent output during industrial fermentations, which favors higher yield with few additional inputs.
Introduction Bioelectrochemical systems (BES) are frequently applied to biological processes as a strategy to elucidate or control dynamics in microbial electrophysiology, but the cost prohibitive nature of most BES acts as a barrier to more extensive proliferation of this tool, particularly in industrial applications. Research groups have previously investigated the development and implementation of low-cost, open source electrochemical systems with great success in applications such as cyclic voltammetry and microbial respirometry [6, 29]. However, the feasibility of applying simple BES as a strategy to enhance native microbial metabolism is still not well understood, and additional investigation is warranted. Previous data suggest that anodic electron Electronic supplementary material The online version of this article (https://doi.org/10.1007/s10295-020-02313-4) contains supplementary material, which is available to authorized users. * Kevin T. Finneran [email protected] 1
Naval Facilities Engineering and Expeditionary Warfare Center, Port Hueneme, CA, USA
Department of Environmental Engineering and Earth Sciences, Clemson University, Clemson, SC, USA
2
stripping enhances cellular bioenergetics in both prokaryotes and eukaryotes, likely by generating thermodynamically favorable metabolic intermediates and by acting as a solidstate surrogate for terminal electron accepting processes or as an electron sink alternative to molecular hydrogen [19, 20, 32, 34]. Electron-mediated enhancement of metabolite production has been studied extensively [12,
Data Loading...
