Different Pathogenic Fungal Species on the Fruit Body and the Stalk of Auricularia polytricha

Abstract

Auricularia polytricha (Jew’s ear) is an important edible fungus in Taiwan. After being processed, the stalks are often used as fertilizer for plant growth. Recently, we developed techniques to extract and purify polysaccharides from the fruit body and stalk of A. polytricha for use as raw materials in the development of value-added products. However, to prevent food toxin-related diseases, we evaluated the microbial contamination, especially that from other fungal species, during A. polytricha processing. Fungal isolates were collected from the A. polytricha fruit body and stalk. PCR amplification of the ITS region was performed, and the PCR products were subjected to restriction endonuclease Sau3A to differentiate the PCR products. The purified PCR products were sequenced and compared with the NCBI database with the BLAST program. The possible fungal species were identified as Mucor irregularis, Mucor fusiformis, and Trichoderma longibrachiatum from the fruit body and Hypocrea koningii, Rhodotorula mucilaginosa, and Coprinellus radians with two genotyoes from the stalk. In conclusion, the fungal species on the fruit body and the stalk were different. Some of these fungi are human pathogens, and a few may be used as biocontrol agents in crop production.