ABSTRACT
Aims@#Microbiota endogenous to oleaginous plants have attracted special attention in recent years for their biotechnological potentials and applications including the production of biodegradable biopolyester poly(3- hydroxybutyrate) [P(3HB)] as an alternative to thermoplastics. The present study is aimed to screen the endophytic bacteria of selected oleaginous plants such as Arachis hypogaea L., Brassica napus L., Brassica nigra L., Helianthus annuus L., Ricinus communis L. and Sesamum indicum L. for the production of P(3HB). @*Methodology and results@#Bacteria endogenous to the oleaginous plants were isolated from surface sterilized healthy tissues following sterilization with 70% ethanol and 0.5% sodium hypochlorite and screened for P(3HB) production in mineral salts medium. Nile blue A staining method was used for detection of intracellular P(3HB), while the accumulated biopolyester was quantified spectrophotometrically following chemical conversion to chrotonic acid by treating with sulfuric acid. Five potent P(3HB) accumulating isolates have been selected and identified as Cellulosimicrobium cellulans AHS 01 (KX458038), Beijerinckia fluminensis AHR 02 (KX458039), Exiguobacterium acetylicum BNL 103 (KX458037), Bacillus toyonensis BNS 102 (KX458036) and Bacillus cereus RCL 02 (KX458035) based on morphological, physio-biochemical and 16S rDNA sequence analysis. These endogenously growing bacterial isolates accumulated intracellular biopolyester accounting 43-62% of their cell dry weight (CDW) when grown in mineral salts medium supplemented with yeast extract. Intracellular accumulation of P(3HB) by these isolates have also been confirmed by FTIR spectral analysis of lyophilized cell mass and 1HNMR spectra of the extracted polymer. @*Conclusion, significance and impact of study@#These findings, first of its kind point to exploration of endogenous bacterial communities of oil-producing plants as a potential bioresource for production of P(3HB) bioplastics in a sustainable manner.