Molecular Characterization of PHB from Soil Bacterial Isolates

Abstract

PHB is a biopolymer which is produced as intracellular storage granules in most of the bacteria. These granules are having properties similar to properties like plastics, but they are completely biodegradable. This property of biodegradability makes them suitable as replacement to conventional plastics. Although numerous comprehensive studies have been performed on the production strategies of PHB, but most of them use chemically defined medium and genetically modified organisms for production. This causes a hike in production cost and in turn affects the final cost of product. The main reason behind unavailability of bioplastic for commercial use may be the production cost and use of genetically modified organisms for production. In this study, an attempt is taken to synthesize PHB by using bacterial isolates collected from natural habitats by using crude carbon sources like groundnut oil cake, paper pulp, whey, ficus racemosa, molasses, and used engine oil. After comparing the production efficiency, the efficient producers are subjected for 16s rRNA sequencing. The results confirmed that they were Bacillus megaterium (MZ 605042), Bacillus cereus (MZ 605040),, Pseudomonas aeruginosa(MZ 605041), Azotobacter chrococcum(MZ 605044) and Pseudomonas aeruginosa(MZ 605043). The produced PHB was also confirmed by using molecular techniques as FTIR, HPLC, GCMS, LCMS, DSC, 1H-NMR and 13C-NMR. All the graphs were confirmed by matching with that of standard PHB. The biodegradation studies of PHB were accomplished by using a liquid broth and a solid agar medium and it was observed that in both conditions the PHB is being utilized as carbon source by the microorganisms. newlineKeywords: PHB, bioplastic, 16s rRNA sequencing, FTIR, HPLC, GC-MS, LC-MS, DSC, 1H-NMR and 13C-NMR. newline