Evaluation of pretreatments for solubilisation of components and recovery of fermentable monosaccharides from microalgae biomass grown in piggery wastewater.

Microalgae-bacteria biomass cultured in wastewater is an interesting renewable material capable of metabolising nutrients from wastes into carbohydrates, proteins, and lipids through photosynthesis. Despite the interest in the valorisation of this biomass to improve the viability of microalgae-based wastewater treatment processes, very scarce research has been devoted to the fractional recovery of its components. This work evaluates the effect of different pretreatments coupled with enzymatic hydrolysis on the solubilisation of biomass components and on the recovery of fermentable monosaccharides (glucose and xylose) from Scenedesmaceae based biomass grown in a thin layer reactor feed with piggery wastewater.

Optimisation of the production of fermentable monosaccharides from algal biomass grown in photobioreactors treating wastewater.

Biomass grown in wastewater treatment photobioreactors is a cheap raw material with high contents of carbohydrates, proteins and lipids. This work studies the production of fermentable monosaccharides from three biomasses grown in piggery wastewater (P), domestic wastewater (W) and synthetic medium (S) by applying chemical pretreatment and enzymatic hydrolysis, using a Taguchi design. ANOVA identified temperature, chemical reagent type and chemical reagent concentration as significant operational parameters.

Effect of pretreatments on biogas production from microalgae biomass grown in pig manure treatment plants.

Methane production from pretreated and raw mixed microalgae biomass grown in pig manure was evaluated. Acid and basic pretreatments provided the highest volatile solids solubilisation (up to 81%) followed by alkaline-peroxide and ultrasounds (23%). Bead milling and steam explosion remarkably increased the methane production rate, although the highest yield (377 mL CH/g SV) was achieved by alkali pretreatment.

Saccharification of microalgae biomass obtained from wastewater treatment by enzymatic hydrolysis. Effect of alkaline-peroxide pretreatment.

An enzymatic method for the carbohydrate hydrolysis of different microalgae biomass cultivated in domestic (DWB) and pig manure (PMWB) wastewaters, at different storage conditions (fresh, freeze-dried and reconstituted), was evaluated. The DWB provided sugars yields between 40 and 63%, although low xylose yields (< 23.5%).

Long-term influence of the presence of a non-aqueous phase on the cell surface hydrophobicity of Pseudomonas in two-phase partitioning bioreactors.

The long-term influence of silicone oil 200 cSt (SO200) and 2, 2, 4, 4, 6, 8, 8-heptamethylnonane (HMN) on the cell surface hydrophobicity (CSH) of a hexane-degrading Pseudomonas aeruginosa strain and a toluene-degrading Pseudomonas putida strain was assessed in two-phase partitioning bioreactors under batch and continuous operation. CSH was evaluated using a modified BATH method based on optical density (CSH(OD)) and colony-forming unit (CSH(CFU)) measurements. In the presence of HMN, P.