Multidimensional interaction mechanisms and engineering applications of microalgae-fungal microorganism symbiotic systems

Yong Zhang; Yang Shen; Yining Gu; Yuan Yao; Meihan Liu; Yike He; Qiuzhen Wang; Yong Zhang; Yang Shen; Yining Gu; Yuan Yao; Meihan Liu; Yike He; Qiuzhen Wang

doi:10.3934/microbiol.2026013

AIMS Microbiology

2026, Volume 12, Issue 2: 298-320. doi: 10.3934/microbiol.2026013

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Review

Multidimensional interaction mechanisms and engineering applications of microalgae-fungal microorganism symbiotic systems

1.
Qinhuangdao Marine Center, the Ministry of Natural Resources, Qinhuangdao, 066000, China
2.
Marine Ecological Restoration and Smart Ocean Engineering Research Center of Hebei Province, Qinhuangdao, 066000, China
3.
The Eighth Geological Brigade, Hebei Geological Prospecting Bureau, Qinhuangdao, 066000, China
4.
Ocean College, Hebei Agricultural University, Qinhuangdao, 066000, China
These authors contribute equally to this work.

Received: 30 March 2026 Revised: 17 May 2026 Accepted: 21 May 2026 Published: 25 May 2026

The symbiotic system of microalgae and fungal microorganisms, such as filamentous fungi, yeasts, and lichen-forming fungi, holds great potential in the fields of environmental remediation and bioresource development. Yet, it faces bottlenecks, including unclear symbiotic mechanisms, high energy consumption for biomass harvesting, poor adaptability to complex wastewater, and insufficient system integration. In this review, we systematically summarized the research progress on microalgae-fungi symbiotic systems in terms of germplasm resource exploration, multifaceted interaction mechanisms, and engineering applications. In particular, we focused on the core advantages of fungal pellet-assisted bioflocculation technology in overcoming the energy bottleneck of biomass harvesting, as well as its optimization strategies. The comprehensive performance of this system in wastewater purification, bioenergy accumulation, and high-value metabolite production was also evaluated. By integrating fundamental mechanisms with engineering application outcomes, we aimed to provide theoretical support and technical guidance for the construction of efficient, stable, and sustainable microalgae-fungi biorefinery platforms. Furthermore, we seek to facilitate the translation of this technology from laboratory research to industrial application.
- microalgae,
- filamentous fungi,
- yeasts,
- wastewater treatment,
- bio-flocculation,
- biorefinery
Citation: Yong Zhang, Yang Shen, Yining Gu, Yuan Yao, Meihan Liu, Yike He, Qiuzhen Wang. Multidimensional interaction mechanisms and engineering applications of microalgae-fungal microorganism symbiotic systems[J]. AIMS Microbiology, 2026, 12(2): 298-320. doi: 10.3934/microbiol.2026013

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Abstract

The symbiotic system of microalgae and fungal microorganisms, such as filamentous fungi, yeasts, and lichen-forming fungi, holds great potential in the fields of environmental remediation and bioresource development. Yet, it faces bottlenecks, including unclear symbiotic mechanisms, high energy consumption for biomass harvesting, poor adaptability to complex wastewater, and insufficient system integration. In this review, we systematically summarized the research progress on microalgae-fungi symbiotic systems in terms of germplasm resource exploration, multifaceted interaction mechanisms, and engineering applications. In particular, we focused on the core advantages of fungal pellet-assisted bioflocculation technology in overcoming the energy bottleneck of biomass harvesting, as well as its optimization strategies. The comprehensive performance of this system in wastewater purification, bioenergy accumulation, and high-value metabolite production was also evaluated. By integrating fundamental mechanisms with engineering application outcomes, we aimed to provide theoretical support and technical guidance for the construction of efficient, stable, and sustainable microalgae-fungi biorefinery platforms. Furthermore, we seek to facilitate the translation of this technology from laboratory research to industrial application.

Acknowledgments

This research was funded by the Open Fund of Marine Ecological Restoration and Smart Ocean Engineering Research Center of Hebei Province (HBMESO2502), Qinhuangdao Key R&D Science and Technology Support Project (202501A090), the Science and Technology Project of Hebei Education Department (BJ2025089), and the Basal Research Fund of Higher Education Institutions in Hebei Province (KY2023087).

Conflict of interest

The authors declare no conflict of interest.

Author contributions

Yong Zhang: Writing–original draft, Writing–review & editing. Yang Shen: Writing–original draft, Writing–review & editing. Yining Gu: Writing–original draft. Meihan Liu: Writing–original draft. Yuan Yao: Writing–review & editing. Yike He: Funding acquisition, Conceptualization, Writing–original draft, Writing–review & editing. Qiuzhen Wang: Funding acquisition, Writing–original draft, Conceptualization, Writing–review & editing.

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