Isolation, Identification and Metabolic Characteristics of a Heterotrophic Denitrifying Sulfur Bacterial Strain

Abstract

Organics,sulfide and nitrogen compounds in industrial wastewater are significant challenges for wastewater treatment. These pollutants could be removed simultaneously from wastewater treatment system using biological technologies. In this study, a heterotrophic denitrifying sulfur bacterial strain HDD1 was isolated from wastewater treatment bioreactor. Strain HDD1 was identified as Thauera sp. based on the 16S rRNA gene phylogenetic analysis and physiological characteristics. Acetate and sulfide could be utilized as electron donors and nitrate as electron acceptor for respiration in Thauera sp. HDD1. The acetate (300 mg·L-1), sulfide (200 mg·L-1) and nitrate (487 mg·L-1) were completely metabolized and removed within 15 hours. The main product of sulfide oxidation was elemental sulfur as identified by scanning electron microscope and energy dispersive spectrometer. These results suggest that the newly isolated Thauera sp. HDD1 could be used for simultaneous industrial wastewater treatment and elemental sulfur resource recovery.