Simultaneous Biosynthesis of Polyhydroxyalkanoates and Extracellular Polymeric Substance (EPS) from Crude Glycerol from Biodiesel Production by Different Bacterial Strains

Abstract

Simultaneous synthesis of polyhydroxyalkanoates (PHAs) and polyglutamic acid (PGA) was investigated in cultures of Cupriavidus necator IPT 026, C. necator IPT 027, C. necator IPT 029, and Bacillus megaterium INCQS 425 strains in a medium containing 2.0 % sucrose or crude glycerol from biodiesel (CGB), in an orbital shaker (35 °C, 180 rpm, 72 h). All the strains tested simultaneously produced PHA and PGA in a medium containing CGB. The C. necator IPT026 culture provided higher molecular mass PHA and PGA (1128.55 and 835.56 kDa, respectively). B. megaterium INCQS 425 promoted PGA production (1.90 g L) with higher crystalline melting temperature (84.04 °C) and higher initial decomposition temperature (247.10 °C). Furthermore, the latter culture promoted the production of medium- and long-chain PHA (0.78 g L) with high crystalline melting temperatures (∼170 °C) and high initial decomposition temperature (307.53 °C) and low degree of crystallinity (20.2 %). These characteristics render these PHAs more appropriate and suitable for processes that require high temperatures, such as extrusion, increasing the possibility of industrial applications, especially in the packaging sector.

Responses of Bacteria from Urban and Desert Soil for Bioplastic Accumulation

“…The biomass from PHA producer strains were subjected to FTIR spectroscopy and for all the strains the peaks were obtained at about 1600 absorbance in both the PHA detection agar supplemented with 2% glucose and 2 % coconut oil as carbon source. The absorbance at these peaks confirms the presence of carboxylic groups, which indicates potential of these strains for bio-plastic production (de Jesus- Assis et al, 2016). The bacterial strains studied in this work are not very well studied, but they have shown promising results for the production of bio-plastic and utilization of lipid carbon source, it has been observed that not a large number of bacteria are able to cleave the ester linkages in the lipids, if a bacterium can break a linkage than it can get a large amount of carbon which is not possible with monosaccharaides or simple disaccharides.…”

Production of butanol and polyhydroxyalkanoate from industrial waste byClostridium beijerinckiiASU10

“…MA03 achieved a considerable amount of intracellular biopolymer (63.6% cell dry weight [CDW]) and final PHB production was 2.9 g L −1 from 2% crude glycerol after 72 hours of cultivation . Zobellella denitrificans utilized crude glycerol (2%) to produce PHA with yield up to 2.82 g L −1 , and those were around fourfold that compared with the amount of PHA produced by Bacillus megaterium INCQS 425 and Cupriavidus necator IPT 027 of 0.78 and 0.33 g L −1 , respectively …”

“…77 Zobellella denitrificans utilized crude glycerol (2%) to produce PHA with yield up to 2.82 g L −1 , and those were around fourfold that compared with the amount of PHA produced by Bacillus megaterium INCQS 425 and Cupriavidus necator IPT 027 of 0.78 and 0.33 g L −1 , respectively. 86 Different concentrations of crude glycerol were used for production of PHA by Bacillus thuringiensis EGU45, whereas the accumulation of PHA inside the bacterial cells increased from 1540 to 3585 mg L −1 by raising the crude glycerol input from 1% to 5%. Meanwhile, the high concentration of crude glycerol (10%) slightly inhibited the production of PHA of 2625 mg L −1 .…”

Caracterização de bactérias halotolerantes isoladas do bioma caatinga e avaliação da produção de biopolímeros.

“…Para começar, o glicerol bruto é gerado como um co-produto na produção de biodiesel, e por cada 10 galões de biodiesel produzido, 1 galão de glicerol bruto é gerado (NARANJO et al, 2013a). Estima-se que até 2016, a produção mundial de biodiesel deve chegar aos 37 bilhões de galões, o que implica uma produção aproximada de 4 bilhões de galões de glicerol bruto (DE JESUS ASSIS et al, 2016b). No Brasil, a mistura de 7% de biodiesel com diesel tornou-se obrigatória em 2014, portanto, a quantidade de biodiesel produzido no Brasil aumentou 241% nos últimos cinco anos, atingindo 9 milhões de galões em 2014 (FABER; FERREIRA-LEITÃO, 2016), sendo este produzido principalmente a partir de soja (ANDRÉ CREMONEZ et al, 2015).…”

“…O custo total de produção de PHB depende do microrganismo (rendimento e produtividade), as fontes de carbono e de nitrogênio (substratos), as condições de fermentação (temperatura, aeração, pH) e os processos de recuperação e purificação(NARANJO et al, 2013b;PRADOS;MAICAS, 2016).Finalmente, os polímeros de PHA podem ser sintetizados por algumas espécies halófilas dos géneros Haloferax,Halococcus, Natronobacterium, Natronococcus, Bacillus, Cupriavidus, Staphylococcus, Micrococcus, Methylobacterium, Paracoccus e Rhodococcus. Dependendo do género, alguns destes microrganismos são capazes de sintetizar, além de PHA, exopolissacarídeos (EPS)(DE JESUS ASSIS et al, 2016a).…”