Optimization of the culture conditions for production of Polyhydroxyalkanoate and its characterization from a new Bacillus cereus sp. BNPI-92 strain, isolated from plastic waste dumping yard.

The aim of this study was to optimize the culture conditions for production, recovery and characterization of polyhydroxyalkanoate (PHA) from potential Bacillus cereus strain BNPI-92. Cost effective carbon sources such as crude oil (CO), rice bran (RB), sugar cane molasses (SCM) and wheat bran (WB) were evaluated for PHA production using the isolate. Higher cell dry weight (CDW) (g/L), PHA concentration (P conc.) (g/L) PHA contents (PC) (%) and PHA synthesis rate (PSR) were obtained from Glucose (60.67% w/v) as a carbon source at 37 °C and pH 7 using Taguchi DOE methods. The polymer was characterized by FTIR and its functional groups (C=O) (1719.41 cm-1 wavenumber) was a characteristic feature of PHB polymer. For 1HNMR, signals of methyne (CH) (5.28 ppm), methylene (-CH2-) (2.45 ppm) and methyl (CH3) (1.27 ppm) and copolymers were predicted. Copolymers such as P (3HB-co-3 HV) and P(3HB-co-3HHX) i.e. characteristic feature of PHB were obtained from a sample of glucose, WB, and RB, respectively. XRD pattern also confirmed the presence of PHA. The major compounds obtained from GC/MS analysis of the polymer recovered from the isolate BNP-92 were 2-butenoic acid, methyl ester (8.6%), ethyl cyclopropanecarboxylate (45.99%), 1-Undecanol (10.18%) which corresponds to and have produced from PHA after thermal degradation.