scholarly journals Marine microalgae co-cultured with floc-forming bacterium: Insight into growth and lipid productivity

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e11217
Author(s):  
Chin Sze Yee ◽  
Victor Tosin Okomoda ◽  
Fakriah Hashim ◽  
Khor Waiho ◽  
Siti Rozaimah Sheikh Abdullah ◽  
...  
Keyword(s):  
Cell Density ◽  
Chlorella Vulgaris ◽  
Lipid Content ◽  
Lipid Accumulation ◽  
Axenic Culture ◽  
Cell Number ◽  
The Other ◽  
Biomass Growth ◽  
Microalgae Biomass ◽  
Insight Into

This study investigated the effect of co-culturing microalgae with a floc-forming bacterium. Of the six microalgae isolated from a biofloc sample, only Thalassiosira weissflogii, Chlamydomonas sp. and Chlorella vulgaris were propagated successfully in Conway medium. Hence, these species were selected for the experiment comparing microalgae axenic culture and co-culture with the floc-forming bacterium, Bacillus infantis. Results obtained showed that the co-culture had higher microalgae biomass compared to the axenic culture. A similar trend was also observed concerning the lipid content of the microalgae-bacterium co-cultures. The cell number of B. infantis co-cultured with T. weissflogii increased during the exponential stage until the sixth day, but the other microalgae species experienced a significant early reduction in cell density of the bacteria at the exponential stage. This study represents the first attempt at co-culturing microalgae with B. infantis, a floc-forming bacterium, and observed increased biomass growth and lipid accumulation compared to the axenic culture.

Simultaneous enhancement of microalgae biomass growth and lipid accumulation under continuous aeration with 15% CO2

RSC Advances ◽  
2015 ◽  
Vol 5 (63) ◽  
pp. 50851-50858 ◽  
Author(s):  
Yun Huang ◽  
Jun Cheng ◽  
Hongxiang Lu ◽  
Rui Huang ◽  
Junhu Zhou ◽  
...  
Keyword(s):  
Lipid Accumulation ◽  
Nitrogen Deprivation ◽  
Biomass Growth ◽  
Microalgae Biomass

Continuous aeration with 15% CO2 induced nitrogen deprivation during Chlorella PY-ZU1 cultivation, thus simultaneously promoting biomass (2.78 g L−1) and lipid (47.04%) production.

scholarly journals Fast media optimization for mixotrophic cultivation of Chlorella vulgaris

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Valerie C. A. Ward ◽  
Lars Rehmann
Keyword(s):  
Cell Density ◽  
Lipid Content ◽  
Lipid Accumulation ◽  
Accumulation Rate ◽  
Lipid Production ◽  
Total Lipid Content ◽  
Mixotrophic Cultivation ◽  
Cell Weight ◽  
Dry Cell Weight ◽  
Dry Cell

AbstractMicroalgae can accumulate large proportions of their dry cell weight as storage lipids when grown under appropriate nutrient limiting conditions. While a high ratio of carbon to nitrogen is often cited as the primary mode of triggering lipid accumulation in microalgae, fast optimization strategies to increase lipid production for mixotrophic cultivation have been difficult to developed due to the low cell densities of algal cultures, and consequently the limited amount of biomass available for compositional analysis. Response surface methodologies provide a power tool for assessing complex relationships such as the interaction between the carbon source and nitrogen source. A 15 run Box-Behnken design performed in shaker flasks was effective in studying the effect of carbon, nitrogen, and magnesium on the growth rate, maximum cell density, lipid accumulation rate, and glucose consumption rate. Using end-point dry cell weight and total lipid content as assessed by direct transesterification to FAME, numerical optimization resulted in a significant increase in lipid content from 18.5 ± 0.76% to 37.6 ± 0.12% and a cell density of 5.3 ± 0.1 g/L to 6.1 ± 0.1 g/L between the centre point of the design and the optimized culture conditions. The presented optimization process required less than 2 weeks to complete, was simple, and resulted in an overall lipid productivity of 383 mg/L·d.

Modulation of lipid metabolism through multiple pathways during oocyte maturation and embryo culture in bovine

Zygote ◽  
2021 ◽  
pp. 1-9
Author(s):  
Clara Slade Oliveira ◽  
Viviane Luzia da Silva Feuchard ◽  
Sheila Costa de Souza Marques ◽  
Naiara Zoccal Saraiva
Keyword(s):  
Lipid Metabolism ◽  
Lipid Content ◽  
Embryo Culture ◽  
Lipid Accumulation ◽  
Time Course ◽  
Cell Number ◽  
Blastocyst Stage ◽  
Multiple Pathway ◽  
Developmental Rates

Abstract Lipid accumulation occurs in cultured embryos and is associated with reduced cryotolerance. Here we report the use of a multiple pathway lipid modulator cocktail (l-carnitine, linoleic acid and forskolin) to improve cryosurvival. First, we stained oocytes and embryos with Oil Red to examine the time course of lipid accumulation during in vitro fertilization (IVF) and embryo culture. Then we evaluated the effects of the lipid modulators cocktail on lipid content, developmental rates and survival after vitrification. In our conditions, lipid accumulation was detected (P < 0.05) at the end of in vitro maturation (IVM) and after 4 days of embryo culture (D4-D5). In experiment 1, we used lipid modulator cocktail during IVM. Reduced (P < 0.05) lipid accumulation was detected in oocytes (Control: 49.9 ± 1.6, Lip. Mod. IVM: 45.0 ± 1.8) but no changes were present at blastocyst stage (Control: 62.4 ± 2.6, Lip. Mod. IVM: 66.8 ± 2.7). Treated oocytes presented decreased (P < 0.05) blastocyst rates and lower (P < 0.05) re-expansion after vitrification. In experiment 2, lipid modulators cocktail was used during embryo culture (from D4–D7 or D6–D7). Treatment had an effect on lipid metabolism, as lipid content was increased (P < 0.05) in D7 blastocysts in treated groups (Control: 52.7 ± 3.1a, D4: 65.9 ± 2.6b, D6: 78.1 ± 2.7b). However, no effect was present for cleavage, blastocyst and cryosurvival rates. No difference was detected in mean cell number comparing the three groups (Control: 78.9 ± 9.6, D4: 82.6 ± 16.5, D6: 68.3 ± 7.8), but apoptosis rate was increased (P < 0.05) in vitrified-warmed blastocysts from treated groups (Control: 14.77*, D4: 22.28, D6: 22.22). We concluded that the combined use of lipid modulators was efficient to promote changes in lipid content of oocytes and embryos in bovine, but those changes did not reflect positively on embryo development or cryosurvival.

scholarly journals Investigation of the Relationship between Bacteria Growth and Lipid Production Cultivating of Microalgae Chlorella Vulgaris in Seafood Wastewater

Energies ◽  
2019 ◽  
Vol 12 (12) ◽  
pp. 2282 ◽  
Author(s):  
Thi Dong Phuong Nguyen ◽  
Duc Huy Nguyen ◽  
Jun Wei Lim ◽  
Chih-Kai Chang ◽  
Hui Yi Leong ◽  
...  
Keyword(s):  
Chlorella Vulgaris ◽  
Lipid Content ◽  
Lipid Accumulation ◽  
Lipid Production ◽  
Oxygen Demand ◽  
Value Added ◽  
Bacteria Growth ◽  
Microalgae Culture ◽  
The Relationship ◽  
Microalgae Growth

Algae biorefinery is gaining much attention for the sustainable production of value-added products (e.g., biofuels, protein supplements etc.) globally. The current study aimed to investigate the relationship between lipid production and bacteria growth by an initial microalgae Chlorella vulgaris density culture in seafood wastewater effluent (SWE). According to our results, the initial C. vulgaris concentration in SWE influenced lipid accumulation. The concentration ranged from 25–35 mg·L−1 which corresponds to SWE’s chemical oxygen demand concentration of 365.67 ± 3.45 mg·L−1. A higher microalgae growth rate and lipid content of 32.15 ± 1.45% was successfully attained. A higher lipid content, approximately double, was observed when compared to the control (16.8 ± 0.5%). Moreover, this study demonstrates that bacteria inhibited microalgae growth as the initial cell density stepped over 35 mg·L−1, which also affected lipid accumulation. This study shows an optimal lipid accumulation attained at moderate Chlorella vulgaris density culture in SWE. Hence, wastewater treatment incorporating microalgae culture could be greatly developed in the future to achieve a greener environment.

scholarly journals The Effect of Chromium on Photosynthesis and Lipid Accumulation in Two Chlorophyte Microalgae

2021 ◽  
Author(s):  
Khawaja Muhammad Imran Bashir ◽  
Hyeon-Jun Lee ◽  
Sana Mansoor ◽  
Alexander Jahn ◽  
Man-Gi Cho
Keyword(s):  
Lipid Content ◽  
Lipid Accumulation ◽  
Culture Medium ◽  
Dry Weight ◽  
Cell Number ◽  
Gravimetric Analysis ◽  
Growth Responses ◽  
Photosynthetic Inhibition ◽  
Negative Effect ◽  
The Impact

Heavy metals have adverse effects on microalgae growth and metabolism. Photosynthesis and lipid profile are quite sensitive to heavy metal toxicity. The impact of chromium (Cr) on growth and photosynthetic activity of Dictyosphaerium pulchellum and Micractinium pusillum exposed to different concentrations (0 &ndash; 500 &mu;g L-1) was investigated for 11 days. The influence of Cr on cell density and cell number followed similar trends, indicating a possible correlation among these growth responses. A significant (p &amp;lt; 0.05) increase in lipid content was observed with the increasing concentration of Cr however, growth was suppressed at higher concentrations exceeding 100 &mu;g L-1. Addition of Cr in the cell culture medium showed a negative effect on quantum yield (Fv/Fm) and a photosynthetic inhibition of &amp;gt; 65% was noted in both species at 500 &mu;g L-1. However, the lipid gravimetric analysis presented inner cell lipid content up to 36% and 30% of dry weight biomass for D. pulchellum and M. pusillum, respectively. The effects of chromium on growth and lipid accumulation in both microalgae species was concentration and exposure time dependent. This shows that an appropriate concentration of chromium in culture medium could be beneficial for higher lipid accumulation in freshwater eukaryotic microalgae species.

scholarly journals Oxygen-Dependent Regulation of Bacterial Lipid Production

2015 ◽  
Vol 197 (9) ◽  
pp. 1649-1658 ◽  
Author(s):  
Kimberly C. Lemmer ◽  
Alice C. Dohnalkova ◽  
Daniel R. Noguera ◽  
Timothy J. Donohue
Keyword(s):  
Fatty Acid ◽  
Rhodobacter Sphaeroides ◽  
Lipid Content ◽  
Lipid Accumulation ◽  
Fatty Acid Content ◽  
Photosynthetic Pigment ◽  
Photosynthetic Apparatus ◽  
Content Type ◽  
Fuels And Chemicals ◽  
Insight Into

ABSTRACTUnderstanding the mechanisms of lipid accumulation in microorganisms is important for several reasons. In addition to providing insight into assembly of biological membranes, lipid accumulation has important applications in the production of renewable fuels and chemicals. The photosynthetic bacteriumRhodobacter sphaeroidesis an attractive organism to study lipid accumulation, as it has the ability to increase membrane production at low O2tensions. Under these conditions,R. sphaeroidesdevelops invaginations of the cytoplasmic membrane to increase its membrane surface area for housing of the membrane-bound components of its photosynthetic apparatus. Here we use fatty acid levels as a reporter of membrane lipid content. We show that, under low-O2and anaerobic conditions, the total fatty acid content per cell increases 3-fold. We also find that the increases in the amount of fatty acid and photosynthetic pigment per cell are correlated as O2tensions or light intensity are changed. To ask if lipid and pigment accumulation were genetically separable, we analyzed strains with mutations in known photosynthetic regulatory pathways. While a strain lacking AppA failed to induce photosynthetic pigment-protein complex accumulation, it increased fatty acid content under low-O2conditions. We also found that an intact PrrBA pathway is required for low-O2-induced fatty acid accumulation. Our findings suggest a previously unknown role ofR. sphaeroidestranscriptional regulators in increasing fatty acid and phospholipid accumulation in response to decreased O2tension.IMPORTANCELipids serve important functions in living systems, either as structural components of membranes or as a form of carbon storage. Understanding the mechanisms of lipid accumulation in microorganisms is important for providing insight into the assembly of biological membranes and additionally has important applications in the production of renewable fuels and chemicals. In this study, we investigate the ability ofRhodobacter sphaeroidesto increase membrane production at low O2tensions in order to house its photosynthetic apparatus. We demonstrate that this bacterium has a mechanism to increase lipid content in response to decreased O2tension and identify a transcription factor necessary for this response. This is significant because it identifies a transcriptional regulatory pathway that can increase microbial lipid content.

A Bird in the Hand Isn’t Good for Long

2018 ◽  
Vol 65 (1) ◽  
pp. 23-31 ◽  
Author(s):  
Stefan Scherbaum ◽  
Simon Frisch ◽  
Maja Dshemuchadse
Keyword(s):  
Decision Making ◽  
Cognitive Control ◽  
The Other ◽  
Decision Task ◽  
Short Term ◽  
Additional Time ◽  
Control Processes ◽  
Folk Wisdom ◽  
Study Participants ◽  
Insight Into

Abstract. Folk wisdom tells us that additional time to make a decision helps us to refrain from the first impulse to take the bird in the hand. However, the question why the time to decide plays an important role is still unanswered. Here we distinguish two explanations, one based on a bias in value accumulation that has to be overcome with time, the other based on cognitive control processes that need time to set in. In an intertemporal decision task, we use mouse tracking to study participants’ responses to options’ values and delays which were presented sequentially. We find that the information about options’ delays does indeed lead to an immediate bias that is controlled afterwards, matching the prediction of control processes needed to counter initial impulses. Hence, by using a dynamic measure, we provide insight into the processes underlying short-term oriented choices in intertemporal decision making.

Correlational Methods for Analysis of Dance Movements

2011 ◽  
Vol 29 (supplement) ◽  
pp. 283-304 ◽  
Author(s):  
Timothy R. Brick ◽  
Steven M. Boker
Keyword(s):  
Motion Capture ◽  
Mirror Symmetry ◽  
Cross Correlation ◽  
The Other ◽  
Free Form ◽  
Motion Capture Data ◽  
Complex Interactions ◽  
Dance Movements ◽  
Time Lagged ◽  
Insight Into

Among the qualities that distinguish dance from other types of human behavior and interaction are the creation and breaking of synchrony and symmetry. The combination of symmetry and synchrony can provide complex interactions. For example, two dancers might make very different movements, slowing each time the other sped up: a mirror symmetry of velocity. Examining patterns of synchrony and symmetry can provide insight into both the artistic nature of the dance, and the nature of the perceptions and responses of the dancers. However, such complex symmetries are often difficult to quantify. This paper presents three methods – Generalized Local Linear Approximation, Time-lagged Autocorrelation, and Windowed Cross-correlation – for the exploration of symmetry and synchrony in motion-capture data as is it applied to dance and illustrate these with examples from a study of free-form dance. Combined, these techniques provide powerful tools for the examination of the structure of symmetry and synchrony in dance.

Marx, Silk Poems, and the Pretext of Qualities

2020 ◽  
Vol 151 (1) ◽  
pp. 96-126
Author(s):  
Kathryn Crim
Keyword(s):  
The Other ◽  
Use Value ◽  
Working Day ◽  
The One ◽  
Insight Into

Karl Marx’s comments on silk manufacture in “The Working Day” chapter of Capital, volume 1, demonstrate how “quality”—usually associated with “use value”—has been mobilized by capital to naturalize industrialized labor. Putting his insight into conversation with a recent multimedia poetic project, Jen Bervin’s Silk Poems (2016–17), this essay examines the homology between, on the one hand, poetry’s avowed task of fitting form to content and, on the other, the ideology of labor that fits specific bodies to certain materials and tasks.

Sign in / Sign up

Export Citation Format

Share Document