Abstract
A growing number of autotrophic microalgae have been found to have extracellular electron transfer (EET) capabilities. However, the mechanism and function of EET pathway in microalgae have not thoroughly investigated. This study presents evidence of direct extracellular electron transfer (DEET) for impressive electricity production by a new type of marine microalgae Nannochloropsis sp. HDY2 in the single and double-chamber photosynthetic microbial fuel cells (PFMCs). The electricity generation of Nannochloropsis sp. is strongly inhibited by photosynthetic inhibitors, suggesting that electrons involved in the extracellular electron transfer (EET) of Nannochloropsis sp. are derived from photosynthesis. The results of dialysis bag and supernatant experiments suggest that Nannochloropsis sp. produce electricity by DEET. The lack of typical redox peaks in cyclic voltammetry (CV) analysis and the appearance of extracellular filamentous component (EFC) around cells support this finding. Under high light conditions, the chlorophyll a and carotenoid content of Nannochloropsis sp. rapidly decreased while the fatty acid synthesis and electricity generation increased, suggesting that the DEET pathway play an active role in the resistance to photooxidation of Nannochloropsis sp. This study provides the first evidence that Nannochloropsis has the capability of performing EET and sheds new light on the positive role of DEET on the environmental adaptation of Nannochloropsis.
| Original language | English |
|---|---|
| Article number | 148636 |
| Journal | Chemical Engineering Journal |
| Volume | 481 |
| DOIs | |
| State | Published - Feb 1 2024 |
Funding
The manuscript preparation for Xiao-Ying Yu was supported by the strategic Laboratory Directed Research and Development (LDRD) of the Physical Sciences Directorate of the Oak Ridge National Laboratory (ORNL). The authors thank Jiyoung Son for technical support in instrument access. ORNL is managed by UT-Battelle, LLC, for the U. S. Department of Energy (DOE) under contract number DE-AC05-00OR22725. This manuscript has been authored by UT-Battelle, LLC under Contract No. DE-AC05-00OR22725 with the U.S. Department of Energy. The United States Government retains and the publisher, by accepting the article for publication, acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes. The Department of Energy will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan (http://energy.gov/downloads/doe-public-access-plan). The project was supported by the National Key Research and Development Program of China (2020YFA0907300), the Open Fund of Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology (LMEES201809), the Guangdong Foundation for Program of Science and Technology Research (2020B1111530002 and 2023B1212060044), the National Natural Science Foundation of China (92251301, U20A20109, 42077044, 41977058 and 42377134), the GDAS' Project of Science and Technology Development (2019GDASYL-0102003, 2019GDASYL-0102002-6, 2021GDASYL-20210103047 and 2022GDASZH-2022010102), the Pearl River Talent Recruitment Program of Guangdong Province (2019QN01L735), the Guangzhou Science and Technology Scheme Project (SL2022A04J00879) and the Guangdong Basic and Applied Basic Research Foundation (2020A1515110446). The manuscript preparation for Xiao-Ying Yu was supported by the strategic Laboratory Directed Research and Development (LDRD) of the Physical Sciences Directorate of the Oak Ridge National Laboratory (ORNL). The authors thank Jiyoung Son for technical support in instrument access. ORNL is managed by UT-Battelle, LLC, for the U. S. Department of Energy (DOE) under contract number DE-AC05-00OR22725. This manuscript has been authored by UT-Battelle, LLC under Contract No. DE-AC05-00OR22725 with the U.S. Department of Energy. The United States Government retains and the publisher, by accepting the article for publication, acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes. The Department of Energy will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan (http://energy.gov/downloads/doe-public-access-plan). The project was supported by the National Key Research and Development Program of China ( 2020YFA0907300 ), the Open Fund of Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology (LMEES201809), the Guangdong Foundation for Program of Science and Technology Research (2020B1111530002 and 2023B1212060044), the National Natural Science Foundation of China (92251301, U20A20109, 42077044, 41977058 and 42377134), the GDAS' Project of Science and Technology Development (2019GDASYL-0102003, 2019GDASYL-0102002-6, 2021GDASYL-20210103047 and 2022GDASZH-2022010102), the Pearl River Talent Recruitment Program of Guangdong Province (2019QN01L735), the Guangzhou Science and Technology Scheme Project (SL2022A04J00879) and the Guangdong Basic and Applied Basic Research Foundation (2020A1515110446).
Keywords
- Direct extracellular electron transfer (DEET)
- Electricity production
- Marine microalgae
- Nannochloropsis sp. HDY2
- ToF-SIMS