Cadmium-resistant oyster mushrooms from North China for mycoremediation

Macrofungi have been advocated to be a promising remediation material for heavy metal pollution. This study aimed to screen for cadmium(Cd)-tolerant oyster mushroom strains which may be used as biomaterials for Cd remediation in North China. To this end, 43 oyster mushroom strains were collected across North China and subject to Cd inhibition test. Phylogenetic affiliation of the tolerant strains was identified using molecular fingerprinting, and representative Cd-tolerant strains were characterized in terms of their Cd sorption capacity. Two strains, JINONG21 and SUYIN6 affiliated with Pleurotus ostreatus, were found to be highly tolerant to Cd, with a minimal inhibitory concentration of 4 mg L~(-1) Cd and a maximal tolerant concentration of 80 mg L~(-1) Cd under the test conditions. Meanwhile, JINONG21 and SUYIN6 were able to absorb up to 676 mg kg~(-1) and 970 mg kg~(-1) Cd in their mycelia in the culture medium with 20 mg L~(-1) Cd, respectively. In conclusion, the P. ostreatus strains identified in this study presented an outstanding capacity of Cd tolerance and sorption and could be promising biomaterials for Cd remediation in North China.