Growth response and mycoremediation of heavy metals by fungus Pleurotus sp.

Heavy metal contamination (HMs) in water and soil is the most serious problem caused by industrial and mining processes and other human activities. Mycoremediation is a biotechnology that employs fungi to remove toxic contaminants from the environment in an efficient and cost-effective manner. Pleurotus spp. have been shown to either increase plant growth on metal-contaminated soils by providing more nutrients or by reducing metal toxicity. Pleurotus species (J. Lange), a mushroom that can be eaten, has been observed growing on plantations of wood trees in Kerman's orchards. P. sp. was the subject of this study, which examined the effects of different concentrations of various heavy metals Cobalt (Co), Copper (Cu), and Nickel (Ni) (0, 15, 30, 45, and 60 mg/L) on fungal colony diameters, mycelial dry weights, accumulation of heavy metals, and antioxidative enzymes. The findings revealed that P. sp. was more tolerant of Co than other metals, so the fungus grew more in the presence of low concentrations of Co and Cu. However, even at concentrations as low as 15 mg/L, Ni greatly inhibited the growth of biomass and colony diameter. Heavy metals increased the activity of superoxide dismutases (SOD) and catalase (CAT) up to 45 mg/L, but an increase in metal concentration above 45 mg/L resulted in a significant decrease in SOD. Metals in mycelium also increased as the concentrations of these heavy metals increased.

Automated summary

Heavy metal contamination in water and soil is a serious issue caused by industrial and mining activities, and mycoremediation using fungi has been shown to be efficient in removing toxic contaminants. Pleurotus species have been found to be more tolerant to cobalt and copper compared to nickel, with nickel concentrations inhibiting fungal growth even at low levels. The study also showed that heavy metals increased the activity of antioxidative enzymes in fungi but resulted in decreased growth and increased metal accumulation at higher concentrations.