Urvija Apparao¹, Veena Gayathri Krishnaswamy^1,

Polyhydroxyalkanoates (PHAs) are polymers which are produced and degraded by many strains of bacteria. They have properties similar to polypropylene, which is a commonly used petrochemical-based plastic. In the present study, five different bacterial strains were isolated from rubber plantation area, of which only one isolate (U1) was able to produce PHA. Screening for PHA was done by Sudan Black B staining and Nile Blue A staining. The strain U1 produced PHA when cultivated in media with different carbon and nitrogen sources, and the optimal carbon-nitrogen source combinations for PHA production was found. PHA extraction was carried out by sodium hypochlorite digestion method. 16S rRNA analysis showed that the PHA-producing bacterium had maximum sequence similarity with Klebsiella pneumoniae. PHA was analysed by UV spectrophotometry and characteristic functional groups were identified by FTIR spectroscopy. In this study, Klebsiella pneumoniae has shown an ability to produce PHAs using different substrates in acidic and halophilic conditions. Therefore, by optimising the process of production, Klebsiella pneumoniae can be used to produce bioplastics in commercially significant amounts.

Polyhydroxyalkonate (PHA), moderately halotolerant, bacterial strain, bioplastics, biopolymer