Screening and Identification of Newly Isolated Basic Red 9-Degrading Bacteria from Textile Wastewater and Their Ability to Produce Medium-Co-Long-Chain-Length Polyhydroxyalkanoates

Newly isolated Basic Red 9-degrading bacteria were isolated from textile wastewater using a pretreatment method. Nine strains were isolated; however, only five strains accumulated polyhydroxyalkanoates (PHAs). Thereafter, PHA-producing strains were identified through 16S rDNA sequencing analysis and phylogenetic evaluation and were found to belong to Enterobacter with 100% identification. The five isolated strains were incubated with a PHAs-producing medium containing 100 mg/l Basic Red 9 (BR9) to study decolorization efficiency, and PHAs production. Enterobacter sp. strains TS3 and TS1L effectively decolorized the BR9 dye with degradation rates of 63.43% and 79.15%, respectively. PHAs production from TS3 and TS1L was also observed to be 75.34% and 72.32% of dry cell weight (DCW), respectively. Furthermore, Enterobacter sp. strains TS3 and TS1L accumulated medium-co-long-chain-length PHAs (mcl-co-lcl PHAs). This is the first report using Enterobacter strains to degrade BR9 dyes from textile wastewater and to assess their ability to produce mcl-co-lcl PHAs.