ISOLATION OF SULFUR OXIDIZING BATERIA FROM PIGGERY WASTES IN SOME PROVINCES OF THE MEKONG DELTA

Abstract

Hydrogen sulfide (H₂S) is a toxic gas and produces offensive rotte egg-like odor when it is present in the air. The aim of this study was to isolate and selection of sulfur oxidizing bacteria from piggery wastes for H₂S removal. The results showed that 49 sulfur oxidizing bacteria isolates were isolated from sediments and wastewater of piggery farms in Vinh Long, Dong Thap, Hau Giang, Soc Trang provinces and Can Tho city. Among them, two isolates T5 and T11 had higher sulfur oxidizing activity than the rest of isolates with sulfate concentration was 150 mg/l after 10 days inoculation. Preliminary application of sulfur oxidizing capacity on piggery wastewater revealed that two isolates T5 and T11 could reduce pH and increase sulfate concentration (T5 and T11 isolates reached 38.64 and 22.52 mg SO₄^2-/l respectively), accompanied with cell growth after 6 days inoculation. Based on their morphological, physiological, biochemical characterization, PCR and 16S rRNA partial sequencing demonstrated that isolate T5 had identity with Acinetobacter sp. 98.08% and T11 had identity with Klebsiella sp. (96.60%) on GenBank.