Polyhydroxybutyrate and hydroxyvalerate production by Bacillus megaterium strain A1 isolated from hydrocarbon‐contaminated soil

Abstract

In this study, we attempted to find an alternative microbial resource as a bioplastic producer. Among all of the isolates, the A1 strain produced 44% poly(β‐hydroxybutyrate) (PHB) in proportion to its dry cell weight. The molecular identification of the 16S RNA gene showed that this bacterium was a strain of Bacillus megaterium with the accession number KC579390. The optimization studies led us to the conclusion that the highest poly(β‐hydroxybutyrate‐co‐hydroxyvalerate) (PHBV) production was 78% when 5% molasses was used as the carbon source at pH 6 and 35°C after 60 h of incubation. Attenuated total reflectance Fourier transform infrared (FTIR) spectroscopy and H‐NMR were used for chemical characterization. Differential scanning calorimetry was used to determine the thermal properties of the PHB and PHBV that were synthesized with sucrose and molasses as carbon sources, respectively. The FTIR spectra of the polymers were characterized by typical absorption bands at 1715–1720 cm−1 for amide‐bound CO bands and 1261–1279 cm−1 for an ester‐bound CO band. The molecular weights of PHB and PHBV synthesized with sucrose and molasses were calculated as 428 and 498 kDa, respectively, according to the viscometric method. This study indicated that the B. megaterium strain A1 is an alternative microbial resource as a bioplastic producer. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40530.

Biosynthesis of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) in Bacillus aryabhattai and cytotoxicity evaluation of PHBV/poly(ethylene glycol) blends

“…The optimum temperature for growth and PHBV accumulation was 31 °C, which was the same as observed during the PHB production studies with this bacterium (Pillai et al 2017a). Besides, Masood et al (2012) and Güngörmedi et al (2014) have also observed that optimum temperature for growth as well as PHA accumulation was in a temperature range of 30-35 °C. The optimum pH for the copolymer production was 7 and the obtained yield showed a significant decreasing trend towards either side of the pH value, which is in agreement with the previous reports on PHBV accumulation in Bacillus spp.…”

“…Reports are also available on the accumulation of copolymers of PHB in several Bacillus spp. when culture medium was supplemented with propionic acid (Güngörmedi et al 2014;Moorkoth and Nampoothiri 2016). B. aryabhattai PHB10 is an environmental bacterial strain accumulating high levels of PHB (Pillai et al 2017a).…”

“…This leads to the copolymer accumulation in bacterial cells. PHBV production in genus Bacillus has been reported previously by supplementing the medium with organic acids (Kumar et al 2006;Güngörmedi et al 2014;Moorkoth and Nampoothiri 2016).…”

Response surface method for polyhydroxybutyrate (PHB) bioplastic accumulation in Bacillus drentensis BP17 using pineapple peel

“…This result is similar to the study of the PHB production from Comamonas sp. [68] and B. megaterium A1 [69]. Acidic pH has no to effect on PHB degradation which is known to depolymerize under alkaline pH conditions [70] and sporulation [71].…”

Designing Novel Interfaces via Surface Functionalization of Short-Chain-Length Polyhydroxyalkanoates

“…). The synthesis of P(3HB-co-3HV) copolymer involves the incorporation of 3HV monomer into the 3HB backbone [12,43,44]. Biopol6 is the trade name that has been producing P(3HB-co-3HV) in a large scale for many years which has been the central PHA marketing strategies by Zeneca and Monsanto [45,46].…”