Assessment of different carbohydrates as exogenous carbon source in cultivation of cyanobacteria

Abstract

Glucose is the substrate most widely used as exogenous carbon source for heterotrophic cultivation of cyanobacteria. Due to limited information about the use of different carbohydrates as carbon sources to support cyanobacterial heterotrophic metabolism, the objective of this work was to evaluate different monosaccharides (arabinose, fructose, galactose, glucose, mannose and xylose), disaccharides (lactose, maltose, sucrose and trehalose) and polysaccharides (carboxymethylcellulose, cassava starch, Hi-maize(®), maltodextrin Corn Globe 1805(®) and xylan) as exogenous carbon source for heterotrophic culture of cyanobacterium Phormidium sp. The batch cultivation using fructose as organic carbon source resulted in the highest (p < 0.05) cell biomass (5,540 mg/L) in parallel with the highest (p < 0.05) substrate yield coefficient (0.67 mg(biomass)/mg(fructose)). Mannose was the carbon source with the highest (p < 0.05) substrate consumption rate (3,185.7 mg/L/day) and maltodextrin was the carbohydrate with major potential to produce biomass (1,072.8 mg(biomass)/L/day) and lipids (160.8 mg(lipids)/L/day). Qualitatively, the fatty acid profiles of the lipid extract from Phormidium sp. showed predominance of saturated chains for the cultures grown with most of the carbon sources, with the exception of the ones grown with xylose and maltodextrin.

Avaliação De Diferentes Amidos Como Substrato Para O Cultivo Heterotrófico De Microalga

“…A presença de maiores concentrações de amilopectina, nos amidos de mandioca favorece o desempenho microalgal, uma vez que as reservas endógenas destes micro-organismos são constituídas do chamado amido cianofíceo, que é composto por α-1,4-glucana, com composição simular ao glicogênio e a amilopectina presente nos amidos de plantas superiores (Francisco et al, 2014). Neste sentido, as células de cianobactérias já estão previamente aclimatadas ao substrato, o que resulta em desempenhos superiores dos cultivos baseados em amidos com elevadas proporções de amilopectina.…”

THIRD GENERATION BIODIESEL PRODUCTION FROM MICROALGAE Phormidium autumnale

“…The culture medium consisted of BG11 synthetic medium modified and supplemented with different concentrations of sucrose to obtain carbon/nitrogen ratios (C/N) of 20, 30, 40, 50, 60, 70 and 80. The concentration of sucrose was adjusted stoichiometrically (Francisco et al, 2014).…”

“…According to Li et al (2007), biodiesel 3G may in turn be produced by microalgae that use sucrose as the substrate, making it a more profitable alternative than ethanol from sugar cane. Additionally, Francisco et al (2014), in a survey of potential carbon sources for microalgae production, identified sucrose as a suitable substrate to support heterotrophic microalgae cultivation. The heterotrophic microalgae possess structurally specific mechanisms for active transport of sucrose into the cell.…”

PRODUÇÃO E EXTRAÇÃO DE Β-Caroteno EM CULTIVO HETEROTROFICO DE MICROALGA PHORMIDIUM SP.

“…As culturas foram realizadas em reator de biorreator bolhas (Francisco et al, 2014), operando em regime de batelada utilizando 2,0 L de água residual como meio de cultura. As condições experimentais foram as seguintes: concentração inicial do inóculo de 100 mg/L, a temperatura de 26 ºC, o pH 7,6, a razão de carbono/nitrogênio de 30 (ajustado com glicose), na ausência de luz e um tempo de residência de 168 horas.…”