Screening and identification of the nitrite-degrading Aspergillus parasiticus JFS

Abstract:

[Objective] Our purpose is to screen the strains that degrade the nitrite. [Methods] We screened the target strains on plate with nitrite selective medium from more than 20 samples such as water, soil and deadwood. We tested the ability of the target strains degrades nitrite by the method of hydrochloric acid naphthalene ethylenediamine. Cadmium column reduction method and test paper method were used to detect the metabolic product of nitrite in the strains. We identified the target strains by morphological characteristics, hyphal and conidial morphology and homology of ITS rDNA sequence and β-Tubulin gene sequence and Calmodulin gene sequence. [Results] We obtained a biodegradable nitrite strains JFS. The strains JFS has a strong ability to degrade nitrite and degrade nitrite to non-toxic nitrate and NH4+. Even concentration of nitrite up to 20% in medium, it also grows very well. According to the morphology, the requirement to culture medium, the 3 gene sequences and phylogenetic studies, the strains JFS belongs to the Aspergillus parasiticus. We identified it as Aspergillus parasiticus. [Conclusion] The strains JFS has a strong ability to degrade nitrite.