Synergism and mutualistic interactions between microalgae and fungi in fungi-microalgae symbiotic system

Junjun Wang; Qinghua Tian; Linlin Cui; Jinju Cheng; Hao Zhou; Yejuan Zhang; Anan Peng; Li Shen

doi:10.1016/j.biortech.2022.127728

Synergism and mutualistic interactions between microalgae and fungi in fungi-microalgae symbiotic system

Bioresour Technol. 2022 Oct:361:127728. doi: 10.1016/j.biortech.2022.127728. Epub 2022 Aug 4.

Authors

Junjun Wang¹, Qinghua Tian¹, Linlin Cui², Jinju Cheng², Hao Zhou², Yejuan Zhang², Anan Peng³, Li Shen⁴

Affiliations

¹ School of Metallurgy and Environment, Central South University, Changsha, Hunan 410083, China.
² School of Minerals Processing and Bioengineering, Central South University, Changsha, Hunan 410083, China.
³ School of Environmental and Chemical Engineering, Foshan University, Foshan 528000, China.
⁴ School of Minerals Processing and Bioengineering, Central South University, Changsha, Hunan 410083, China. Electronic address: lishen@csu.edu.cn.

PMID: 35932943
DOI: 10.1016/j.biortech.2022.127728

Abstract

The method of collecting microalgae using fungal mycelium pellets has attracted widespread attention because of its high efficiency and simplicity. In this study, the interaction in FMSS was explored using Aspergillus fumigatus and Synechocystis sp. PCC6803. Under the conditions of 25-30 °C, pH of 5.0, 160 rpm, a light intensity of 1000 lx, light to darkness ratio of 6:18 h, and glucose concentration of 1.5 g/L, the FMSS had the highest biomass and recovery efficiency. SEM, TEM, and Zeta analysis showed that microalgae can be fixed on the surface of fungal mycelium pellets by the electrostatic attraction (amino, amide, phosphate, hydroxyl, and aldehyde groups) of EPS. The N cycling and CO₂-O₂ cycling promoted the synthesis of amino acids and provided a guarantee for gas exchange, and the intermediate metabolites (CO₃^2- and HCO₃^-/H₂CO₃) satisfied the metabolic activities. The microalgae and fungi worked in coordination each other, which was the mutualistic symbiosis.

Keywords: Aspergillus fumigatus; Electrostatic attraction; Extracellular polymeric substances (EPS); Mutualistic symbiosis; Synechocystis sp. PCC6803.

MeSH terms

Biomass
Fungi
Microalgae* / metabolism
Symbiosis
Synechocystis* / metabolism