The effect of high-intensity ultrasound on cell disruption and lipid extraction from high-solids viscous slurries of Nannochloropsis sp. biomass

Yao, Shunyu; Mettu, Srinivas; Law, Sam Q.K.; Ashokkumar, Muthupandian; Martin, Gael M.

doi:10.1016/j.algal.2018.09.004

Cited by 49 publications

(27 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This effect has yet to be studied directly, although recently we observed that the high-shear viscosity of a 20% solids Nannochloropsis sp. slurry increased 3-fold following ultrasonic cell rupture [6].…”

Section: Introductionmentioning

confidence: 97%

“…Processing partially dewatered suspensions can address this challenge by avoiding energy-intensive thermal drying and minimising capital costs [3,4]. Hence, there is an emphasis on using high-solids slurries during both cell rupture and lipid extraction [1,[3][4][5][6][7]. Slurries around 20-25% solids (the typical limit of physical dewatering) are optimal for lowering the specific energy consumption per unit dry mass of algae processed or unit of lipid produced [3,4].…”

Section: Introductionmentioning

confidence: 99%

“…For example, recently it was shown that high-solids slurries of the marine microalgae Nannochloropsis sp. can be efficiently ruptured using a high-pressure homogeniser (HPH) [7] or high-intensity ultrasonicators [6] in viscous slurries of up to 25 and 20% solids, respectively. In the latter study, it was found that the high-shear viscosity of a slurry of intact Nannochloropsis sp.…”

Section: Introductionmentioning

confidence: 99%

“…In the latter study, it was found that the high-shear viscosity of a slurry of intact Nannochloropsis sp. cells increased by more than two orders of magnitude (from 85 to about 15,000 mPa.s) when the solids concentration was increased from 20 to 25%, limiting the effectiveness of ultrasonic rupture [6]. Such a high viscosity also introduces significant challenges for pumping and processing the slurries.…”

Section: Introductionmentioning

confidence: 99%

“…For example, in the case of hard-to-rupture cells like Nannochloropsis sp., slurries are incubated to weaken the cell walls and then mechanically ruptured by high-pressure homogenisation (Fig. 1) to allow extraction of the lipids [6,7,24,25]. Alternatively, pulsed electric fields can be used to permeabilise the cells for the recovery of proteins [21].…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Rheological properties of concentrated slurries of harvested, incubated and ruptured Nannochloropsis sp. cells

et al. 2019

Self Cite

View full text Add to dashboard Cite

Biorefining of microalgae biomass requires processing of high-solids (> 10%) slurries. To date there is little knowledge of how processes for weakening and rupturing microalgae cells affect the rheological properties of these materials. To fill this gap in the literature, the rheological properties of concentrated slurries of marine microalgae Nannochloropsis sp. were investigated as a function of processing and solids concentration (12, 20 and 24% w/w). Freshly harvested, incubated (autolysed), and high-pressure homogenised (HPH) slurries were found to be shear thinning up to a shear rate of approximately 200 s − 1. Viscosity increases were far more prominent for partially processed versus unprocessed algal pastes at the higher concentrations. Slurry viscosity as a function of cell volume fraction could not be fitted to the Krieger-Dougherty model due to a network structure resulting from extracellular polymeric substances (EPS) and the intracellular cell components released during incubation and cell rupture. The 24% slurry, which was near the close packing limit, was much more viscous than the less concentrated slurries when comprising whole cells (i.e. harvested and incubated slurries). Cell rupture by HPH completely altered the characteristics of the slurry, increasing the viscosity of even the less concentrated slurries, and producing irreversible shear thinning behaviour. The magnitude of the increases in viscosities and the irreversible shear thinning behaviour observed in this study, have significant implications for processing and optimising the solids concentration of algal slurries.

show abstract

Section: Introductionmentioning

confidence: 97%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Rheological properties of concentrated slurries of harvested, incubated and ruptured Nannochloropsis sp. cells

et al. 2019

Self Cite

View full text Add to dashboard Cite

show abstract

Effect of processing on protein solubility of Chlorella sorokiniana dispersions

Li,

Mejdahl,

Jørgensen

et al. 2024

Sustainable Food Proteins

View full text Add to dashboard Cite

Potential exists in the utilization of Chlorella biomass as a source for food ingredients, due to an increased demands for more environmentally friendly sources of high‐quality proteins. This study investigated the protein solubility of white Chlorella sorokiniana dry powders, containing either whole cells or homogenized cells as a function of pH. The effect of different cell disruption methods was evaluated. The results demonstrated that protein solubility can be improved by resuspending the powder at alkaline pH (pH 8). The highest solubility was achieved for the homogenized powder, which reached approximately 18% protein at pH 8 compared to a value of 8% at its original pH (pH 4.6). High intensity ultrasonication and high‐pressure homogenization increased protein extraction efficiency, while pre‐heating at 40°C did not have any significant effects. Overall, the results demonstrate how the design of the processing can aid in ensuring higher protein solubility, and contribute to facilitating the potential utilization of chlorella biomass as a protein source.

show abstract

Catalytic Hydrothermal Liquefaction of Algal Biomass for Diesel Like Bio-Crude Oil

Roy,

Sinha,

Roy

2024

Environmental Science and Engineering

View full text Add to dashboard Cite

The effect of high-intensity ultrasound on cell disruption and lipid extraction from high-solids viscous slurries of Nannochloropsis sp. biomass

Cited by 49 publications

References 42 publications

Rheological properties of concentrated slurries of harvested, incubated and ruptured Nannochloropsis sp. cells

Rheological properties of concentrated slurries of harvested, incubated and ruptured Nannochloropsis sp. cells

Effect of processing on protein solubility of Chlorella sorokiniana dispersions

Catalytic Hydrothermal Liquefaction of Algal Biomass for Diesel Like Bio-Crude Oil

Contact Info

Product

Resources

About