A novel mycelial pellet applied to remove polycyclic aromatic hydrocarbons: High adsorption performance & its mechanisms

• Published in: The Science of the total environment 2024-04, Vol.922, p.171201-171201, Article 171201
• Main Authors: Zou, Jia Jie, Dai, Chaomeng, Hu, Jiajun, Tong, Wang Kai, Gao, Min-tian, Zhang, Yalei, Leong, Kah Hon, Fu, Rongbing, Zhou, Lang
• Format: Article
• Language: English
• Subjects: adsorbents; Adsorption; anthracenes; biosorbents; Biosorption; Biosorption mechanism; cost effectiveness; environment; Extracellular polymeric substances; fluorenes; humic acids; hydrophobicity; mass transfer; molecular weight; Mycelial pellets; Mycelium; Penicillium; Penicillium thomii; phenanthrenes; Polycyclic aromatic hydrocarbons; Polycyclic Aromatic Hydrocarbons - analysis; polymers; Pyrenes; reaction kinetics; salt concentration; toxicity
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2024.171201

Mycelial pellets formed by Penicillium thomii ZJJ were applied as efficient biosorbents for the removal of polycyclic aromatic hydrocarbons (PAHs), which are a type of ubiquitous harmful hydrophobic pollutants. The live mycelial pellets were able to remove 93.48 % of pyrene at a concentration of 100 mg/L within 48 h, demonstrating a maximum adsorption capacity of 285.63 mg/g. Meanwhile, the heat-killed one also achieved a removal rate of 65.01 %. Among the six typical PAHs (pyrene, phenanthrene, fluorene, anthracene, fluoranthene, benzo[a]pyrene), the mycelial pellets preferentially adsorbed the high molecular weight PAHs, which also have higher toxicity, resulting in higher removal efficiency. The experimental results showed that the biosorption of mycelial pellets was mainly a spontaneous physical adsorption process that occurred as a monolayer on a homogeneous surface, with mass transfer being the key rate-limiting step. The main adsorption sites on the surface of mycelia were carboxyl and N-containing groups. Extracellular polymeric substances (EPS) produced by mycelial pellets could enhance adsorption, and its coupling with dead mycelia could achieve basically the same removal effect to that of living one. It can be concluded that biosorption by mycelial pellets occurred due to the influence of electrostatic and hydrophobic interactions, consisting of five steps. Furthermore, the potential applicability of mycelial pellets has been investigated considering diverse factors. The mycelia showed high environmental tolerance, which could effectively remove pyrene across a wide range of pH and salt concentration. And pellets diameters and humic acid concentration had a significant effect on microbial adsorption effect. Based on a cost-effectiveness analysis, mycelium pellets were found to be a low-cost adsorbent. The research outcomes facilitate a thorough comprehension of the adsorption process of pyrene by mycelial pellets and their relevant applications, proposing a cost-effective method without potential environmental issues (heat-killed mycelial pellets plus EPS) to removal PAHs. [Display omitted] •A novel strain, Penicillium thomii ZJJ was isolated from soil.•It showed excellent biosorption capacity and high tolerance to six typical PAHs.•In the presence of multiple PAHs, the strain first adsorbed highest toxic PAHs.•Max adsorption capacities of live or dead strain were 286 and 199 mg/g, respectively.•EPS can synergize with live or dead mycelial pelle