Utilization of vinasse for the production of polyhydroxybutyrate by Haloarcula marismortui

Abstract

Vinasse, a recalcitrant waste of the ethanol industry was employed for the production of polyhydroxyalkanoate (PHA) by the extremely halophilic archaeon, Haloarcula marismortui in shake flasks. The PHA was recovered by osmotic lysis of the cells and subsequent purification by sodium hypochlorite and organic solvents. Through UV-vis spectroscopy, differential scanning calorimetry, Fourier transform infrared, and nuclear magnetic resonance spectroscopy, the PHA was found to have characteristics very similar to that of the standard polyhydroxybutyrate (PHB) from Sigma. Inhibitory effect of polyphenols contained in vinasse was assessed by a quick and reliable cup-plate agar-diffusion method. Raw vinasse (10%) was utilized leading to accumulation of 23% PHA (of cell dry weight) and following an efficacious pre-treatment process through adsorption on activated carbon, 100% pre-treated vinasse could be utilized leading to 30% accumulation of PHB by H. marismortui. Maximum specific growth rate, specific production rate, and volumetric productivity attained using 10% raw vinasse were comparable to that obtained using a previously reported nutrient deficient medium (NDM), while the values with 100% pre-treated vinasse were higher than that determined using NDM medium. This is the first report of polyhydroxybutyrate production by a halophilic microorganism utilizing vinasse.

Utilization of vinasse for production of poly-3-(hydroxybutyrate-co-hydroxyvalerate) by Haloferax mediterranei

“…One hundred milliliters raw vinasse was adjusted to pH 2.0 and treated with 5.0 g activated carbon (AC) as described in Pramanik et al ([2012]). The AC was removed by centrifugation, the supernatant filtered, neutralized with NaOH/HCl as required and the filtrate characterized as mentioned in the sub-section, “Analytical Methods”.…”

“…Petri plates were prepared containing the growth medium (GM) as suggested by DSMZ, composed of (g/l) NaCl 200.0; MgSO 4 .7H 2 O 20.0; KCl 2.0; casamino acids 5.0; yeast extract 5.0; C 5 H 8 NNaO 4 1.0; Na 3 C 6 H 5 O 7 3.0; FeCl 2 .4H 2 O 0.036; MnCl 2 .4H 2 O 0.00036; pH 7.0-7.2, swabbed with H. mediterranei culture containing 10 8  CFU/ml and further evaluated as described in Pramanik et al ([2012]).…”

“…In our previous article (Pramanik et al [2012]), we provided the first report of PHB production by a halophilic microorganism, Haloarcula marismortui utilizing vinasse. Our long term objective is to expand the possibility of PHA production by other extreme halophiles consuming vinasse.…”

Potential application of a bioemulsifier-producing actinobacterium for treatment of vinasse

“…MC1, including at concentrations where growth of other microorganisms is usually inhibited. Pramanik et al (2012), e.g., reported on the inhibitory effects of vinasse on the growth of the bacterium Haloarcula marismortui at concentrations above 10%. Omar et al (2002) found that nitrogenfixing bacterial strains such as Azospirillum brasiliense, Bacillus polymyxa, and Azotobacter chroococcum were only able to utilize concentrations of 6e15% of vinasse obtained from an Egyptian distillery.…”

PRODUÇÃO DE POLI(3-HIDROXIBUTIRATO) por Cupriavidus necator UTILIZANDO VINHAÇA COMO SUBSTRATO

“…Assim como o residual de material orgânico, ao final do cultivo ainda havia ART disponível no meio, como mostrado na Figura 2 (b). Pramanik et al (2012) utilizaram vinhaça para a produção de P(3HB) a partir de Haloarcula marismortui, um microrganismo halofílico (capaz de crescer em elevadas concentrações de sais) e o acúmulo final de P(3HB) em meio contendo 10 % (v/v) de vinhaça foi de 30 % (m/m) com μ Xrmax de 0,086 h -1 . É importante ressaltar que, apesar do acúmulo de P(3HB) do cultivo apresentado neste trabalho, com estratégia de pulso e limitação em nitrogênio assim como para os autores citados, ter ficado em torno de 30 %, este trabalho utilizou um microrganismo não halofílico e as concentrações de vinhaça avaliadas foram superiores (até 100 %), demonstrando que a bactéria abordada neste estudo, apesar de não ser um microrganismo halofílico, foi capaz de crescer e produzir P(3HB) em meio de cultivo contendo elevadas concentrações de vinhaça.…”