High production of poly(3-hydroxybutyrate) from a wildBacillus megateriumBolivian strain

Abstract

Aim: Taking into account that a novel strain of Bacillus megaterium was isolated from Uyuni salt lake (Bolivia) in a previous work, the objectives of this new study were to determine the maximal Poly-3-hydroxybutyrate production potential of B. megaterium strain uyuni S29 in an industrial conventional media, the possibility that the strain accumulates different types of polyhydroxyalkanoates, the cellular morphology during the biosynthesis process and the characterization of the produced biopolymers. Methods and Results: The micro-organism was first tested in a 3-L bioreactor obtaining a high specific growth rate of 1Á64 h À1 . A second fed-batch experiment was carried out in shaking flasks, reaching up to 70% PHB of cell dry mass. The biosynthesized polymers were extracted by two different extraction procedures and characterized. The results showed that all of them were PHB with thermal properties different to the conventional PHB. The micrographs taken by TEM show the different cell morphology during the fermentation process. Conclusions: In this previous study, the strain not only grew properly in the industrial conditions proposed without spore formation, but also produced and accumulated a large content of PHB, never reached before for its genus. Therefore, if the culture conditions can be optimized, the biopolymer production could be increased. Significance and Impact of the Study: The impact of the study has related to the area of the biomaterials and their production. The study provides new data related to the high production of PHB from the wild novel strain B. megaterium uyuni S29, the highest polymer accumulation for the genus Bacillus without spores formation.

Production of Polyhydroxyalkanoate (PHA) Biopolyesters by Extremophiles?

“…Gram-positive thermophile PHA producers: In contrast to the huge number of reports on PHA production by Gram-negative bacteria and archaea, investigation of Gram-positive microbes able to produce PHA efficiently is still manageable, especially regarding the small number of reports on PHA production by extremophile Gram-positive strains [81]. However, PHA produced by Gram-positives is characterized by low levels of LPS causing immunogenic reactions, making them interesting for biomedical applications.…”

“…This strain, originally isolated from the Uyuni salt lake in Bolivia [79], features high capacity of PHB production in typical nutrient media used in industrial biotechnology [80]. The impact of fluctuating salinity on growth and PHB production by this strain was assessed under different NaCl concentrations selected according to the salinities dominant in the strain's natural salt lake environment [81]. The strain displayed astounding adaptability to fluctuating salinity, with best results for growth and PHB accumulation at 45 g/L NaCl.…”

Amylase Producing Bacillus megaterium T04 Isolated in Rach Lang Stream of Vietnam

“…Microorganisms can produce many kinds of products such as lipase (Sekhon et al, 2003), poly (3-hydroxybutyrate) (Rodrıguez-Contreras, 2013), potential proteins (Vary et al, 2007). Among their products, amylases are hydrolases than can breakdown or hydrolysis starch.…”

Simplified recovery process of Ralstonia solanacearum-synthesized polyhydroxyalkanoates via chemical extraction complemented by liquid-liquid phase separation

“…and recombinant Escherichia coli. [6][7][8][9] Ralstonia spp. tend to be more amenable to production on an industrial scale, demonstrating high yields and production rates, 10 accumulating approximately 80% of its dry weight as polymer.…”

“…1,[7][8][9]13 Thus, there is an urgent need for research into the improvement of the polymer extraction process. We believe that this study will contribute to a more practical production, efficient recovery of P(3HB), representing an important contribution to this field of study.…”