Jing-Ye Tee , Fiona Seh-Lin Keng , Fong-Lee Ng , Gill Malin , Choon-Weng Lee , Siew-Moi Phang
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引用次数: 0
Abstract
As interest in utilizing microalgae for biophotovoltaics (BPV) grows, assessing the environmental impacts, especially under varying temperatures, becomes crucial. This study examines how temperatures from 25 to 37 °C affect halocarbons emissions and bioelectricity generation by Synechococcus sp. UMACC 371 in a BPV device. Six halocarbons were investigated, with highest emission rates observed for CH3I (49.63 pmol mg−1 day−1) and CHBr3 (65.39 pmol mg−1 day−1). Emissions of iodinated compounds (CH3I, CH2I2) increased at 37 °C and were positively correlated with temperature (r = 0.703 to 0.746, p < 0.01). Lower Fv/Fm value and negative correlations between emissions and Fv/Fm suggest that cell stress increases emissions. CHBr3 and CHBr2Cl emissions were higher at lower temperatures and negatively correlated with temperature (r = −0.627 to −0.912, p < 0.01). Higher Fv/Fm at lower temperatures suggests these emissions were enhanced under optimal conditions rather than temperature stress. The highest specific growth rate and chlorophyll-a content at 37 °C, contributed to the highest power density of 3.94 mW m−2. While temperature showed little correlation with normalized power output, a positive correlation between normalized power density and CH2I2 emission suggests an indirect link. Further studies are needed to understand the connection between halocarbon emissions and bioelectricity generation in BPV. This study reveals that temperature fluctuations affect halocarbon emissions and bioelectricity generation from Synechococcus sp. UMACC 371, addressing the effects of varying temperatures on these processes in tropical microalgae. This is particularly relevant considering the potential widespread deployment of microalgae-based BPV devices in outdoor environments.
期刊介绍:
Algal Research is an international phycology journal covering all areas of emerging technologies in algae biology, biomass production, cultivation, harvesting, extraction, bioproducts, biorefinery, engineering, and econometrics. Algae is defined to include cyanobacteria, microalgae, and protists and symbionts of interest in biotechnology. The journal publishes original research and reviews for the following scope: algal biology, including but not exclusive to: phylogeny, biodiversity, molecular traits, metabolic regulation, and genetic engineering, algal cultivation, e.g. phototrophic systems, heterotrophic systems, and mixotrophic systems, algal harvesting and extraction systems, biotechnology to convert algal biomass and components into biofuels and bioproducts, e.g., nutraceuticals, pharmaceuticals, animal feed, plastics, etc. algal products and their economic assessment