Isolation and molecular identification of the bacteria involved in removing phosphate from industrial wastewater

Phosphate is one of the most important contaminants entering recipient waters (rivers, lakes, and seas) by wastewater disposal and causative agent of eutrophication due to the enrichment of aquatic ecosystems. In bioremediation process, the phosphate-removing bacteria accumulate polyphosphate intracellularly and take it away from the environment. The objective of this study was to isolate and identify the bacteria which remove phosphate from industrial wastewater.
In this study, phosphate-removing bacteria were isolated from wastewaters of Aq Qlala industrial park of Golestan province. The isolates were identified based on the creation of clear zone in the bacterial lawn, leading to phosphate removal on the specific agar plate Seperb. Finally, the isolates were identified by macroscopical, microscopical, biochemical, and molecular methods.
Findings: In total, 3 out of 30 isolates had high ability in phosphate removal regarding their large clear zone on agar. Molecular identification of isolates by 16S rDNA typing method indicated that the isolates belong to the genera Brevundimonas, Ochrobactrum, Exiguobacterium.
Variance analysis using SAS 9.2 software indicated a significant difference in phosphate removal by the isolates. The obtained results demonstrated that the isolates are highly efficient in phosphate removing from wastewater and they are suitable candidates for bioremediation along with other methods.