Mechanistic insights of Cystobasidium slooffiae JSUX1: Yeast-derived microbial fuel cells and conversion of organic wastes to electricity

Jamile Mohammadi Moradian; Amjad Ali; Gang Pei

Authors

Jamile Mohammadi Moradian Department of Thermal Science and Energy Engineering, University of Science and Technology of China, Hefei, Anhui, China https://orcid.org/0000-0001-5753-6867
Amjad Ali Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Materials Science and Engineering, Nanjing Forestry University, Nanjing, Jiangsu, China https://orcid.org/0000-0001-7112-4922
Gang Pei Department of Thermal Science and Energy Engineering, University of Science and Technology of China, Hefei, Anhui, China https://orcid.org/0000-0002-1718-4227

Keywords:

Microbial fuel cells, Yeast, Cystobasidium slooffiae, Electricity, Biohydrogen, Extracellular electron transfer, Untreated lignocellulosic biomass, Xylose

Abstract

The pursuit of sustainable energy from abundant and renewable waste biomass has positioned microbial fuel cells (MFCs) as a capable technology. While bacterial MFCs are widely studied, yeast-based MFCs offer advantages in safety, ease of handling, and broader substrate utilization. The recent discovery and characterization of the exoelectrogenic yeast Cystobasidium slooffiae JSUX1 have opened new avenues for direct biomass-to-energy conversion. This review synthesizes recent advancements in leveraging C. slooffiae JSUX1 for efficient electricity and hydrogen production from pentose sugars and raw lignocellulosic biomass. We delve into the unique extracellular electron transfer mechanisms employed by this strain, notably its secretion of riboflavin and the newly identified role of humic acid-iron complexes (Fe-HA) derived from biomass degradation. C. slooffiae JSUX1 MFCs achieved peak power densities up to ≈152 mW/m2 and hydrogen yields ≈41 L/m3 (with engineered anodes), roughly double the baseline values of 67 mW/m2 and 16 L/m3 . We further analyze applied strategies for enhancing MFCs’ performance through anode engineering, including yeast-induced reduced graphene oxide hydrogels and polyaniline nanofiber anodes. These anode modifications significantly improved anode conductivity, microbial adhesion, and interfacial charge transfer, leading to a dramatic boost in simultaneous power and hydrogen output. This review consolidates the mechanistic understanding of C. slooffiae JSUX1 and situates it within broader yeast-MFC research trends, outlining its potential as a new biocatalyst for developing waste-valorizing bioelectrochemical systems.