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Published on: September 6, 2024
Methanogenic recovery under organic overload using starfish-derived powder
Hyeongyu An1, Juhee Shin2, Ilho Bae1
1Department of Energy System Engineering, Gyeongsang National University, Jinju, Gyeongnam, Republic of Korea.
Frontiers in Microbiology
|July 2, 2026
Summary
Starfish powder effectively buffers and restores anaerobic digestion under starch overload conditions. This biomass valorization offers a sustainable solution for managing starfish populations and improving biogas production.
Area of Science:
- Environmental Science
- Biotechnology
- Waste Management
Background:
- Starfish overpopulation presents ecological and economic challenges.
- Collected starfish biomass is often disposed of via incineration or landfilling.
- Starfish biomass, rich in CaCO3 and biodegradable matter, has potential for valorization in anaerobic digestion (AD).
Purpose of the Study:
- To evaluate the buffering and recovery effects of starfish powder (SF) in starch-induced overloaded anaerobic digestion.
- To assess starfish biomass as a multifunctional additive for improving AD stability and performance.
Main Methods:
- Starfish (Asterina pectinifera and Asterias amurensis) were dried and pulverized.
- Physicochemical properties and theoretical biochemical methane potential (TBMP) were characterized.
- Long-term batch assays compared starch overload alone, CaCO3 supplementation, and SF addition.
Main Results:
- Starfish powder (SF) as a sole substrate yielded 490 mL CH4/g VS (59-73% of TBMP).
- Under starch overload, SF addition enabled recovery of methane production (60-78% of expected yield), unlike CaCO3.
- Microscopy and 16S rRNA sequencing revealed enhanced microbial colonization and shifts in bacterial and methanogenic communities with SF addition.
Conclusions:
- Starfish powder acts as a slow-acting alkalinity source, promoting digester recovery through physicochemical buffering and microbial restructuring.
- SF addition stabilizes overloaded anaerobic digesters, enhancing long-term performance and offering a sustainable waste valorization pathway.
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