Poly(3‐hydroxybutyrate‐co‐3‐hydroxyvalerate) production from biodiesel by‐product and propionic acid by mutant strains of Pandoraea sp.

Abstract

Pandoraea sp. MA03 wild type strain was subjected to UV mutation to obtain mutants unable to grow on propionic acid (PA) but still able to produce poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(3HB-co-3HV)] from glycerol and PA at high 3HV yields. In shake flask experiments, mutant prp25 was selected from 52 mutants affected in the propionate metabolism exhibiting a conversion rate of PA into 3HV units of 0.78 g g . The use of crude glycerol (CG) plus PA or valeric acid resulted in a copolymer with 3HV contents varying from 21.9 to 30 mol% and 22.2 to 36.7 mol%, respectively. Fed-batch fermentations were performed using CG and PA and reached a 3HV yield of 1.16 g g , which is 86% of the maximum theoretical yield. Nitrogen limitation was a key parameter for polymer accumulation reaching up to 63.7% content and 18.1 mol% of 3HV. Henceforth, mutant prp25 is revealed as an additional alternative to minimize costs and support the P(3HB-co-3HV) production from biodiesel by-products. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:1077-1084, 2017.

Polyhydroxyalkanoate synthesis based on glycerol and implementation of the process under conditions of pilot production

“…To date, the synthesis of PHAs (mainly P(3HB) but also copolymers P(3HB/3HV), P(3HB/4HB)) has been studied under different cultivation conditions on a mineral salt medium containing glycerol by natural strains of various taxa: Methylobacterium rhodesianum [5], Methylobacterium extorquens [39], Cupriavidus necator [28], Paracoccus denitrificans [28], Pseudomonas oleovorans [3], Pseudomonas corrugate [3], Burkholderia cepacia [49], Caldimonas manganoxidans [17], as well as mutant microorganisms, for example, Cupriavidus necator DSM 545 [7,8], Pandoraea sp. prp25 [13] and recombinant strains Ralstonia eutropha KNK-DCD1 [42], E.coli CT106 [30] (Table 1). Processes were described that were implemented in shake flask сultures and fed-batch cultures in fermenters from 2.0 to 10-15 L; as well as a scaled process of P(3HB) synthesis by Burkholderia cepacia ATCC 17759 at a culture volume of 200 L [49].…”

Recent Progress in Polyhydroxyalkanoates‐Based Copolymers for Biomedical Applications

“…However, despite its excellent material performances for kinds of applications, the high production costs make it prohibitive. Raw materials are the main expense in production costs . Therefore, using inexpensive raw materials and developing high‐yield bacterial strains are very important for producing PHBV.…”

Prospective Biodegradable Plastics from Biomass Conversion Processes

“…A glucose-affected mutant of Cupriavidus necator, former Ralstonia eutropha and a traditional PHA-producing strain, is able to accumulate PHB from crude glycerol [85]. Additionally, new wild bacterial strains have been isolated from the environment such as Pandoraea sp., which is able not only to produce PHAs from crude glycerol but also from sugarcane molasses and waste cooking oil, although the best polymer yields were obtained from crude glycerol [24].…”

“…Moreover, the biofuel byproducts have been a source of chemicals. Crude glycerol from transesterification of fats and oils, a byproduct of biodiesel industry, has been a promising feedstock to obtain a high diversity of products from microbial cultivation, which may be mentioned as 1,3-propanediol, dihydroxyacetone, succinic acid, propionic acid, ethanol, citric acid, biosurfactants, and bioplastics [15][16][17][18][19][20][21][22][23][24]. Lignocellulose hydrolysates are not only a source of the second-generation ethanol but also a feedstock of a multitude of chemicals such as xylose, mannose, galactose, acetic acid, ethylene, propylene, butadiene, xylitol, phenols, glucaric acid, glutamic acid, aspartic acid, syringols, eugenol, toluene, xylene, styrene, and others [14,[25][26][27][28][29][30][31][32][33].…”