1. Bruna Ferreira Silva Chemistry Institute Federal University of Goiás
Environmental Health and Safety 2016 Conference
Analysis of some chemical elements in marine microalgae for biodiesel production and other uses
Bruna Ferreira Silva
Chemistry Institute
Federal University of Goiás
Valencia - Spain
October, 2016

3. Outline Introduction Objective Materials and Methods
Microalgae cultivation and sampling
Light microscopy
Biomass Digestion
ICP-OES analysis
Chemometric analysis
Results and Discussion
Chemical elements in marine microalgae
Conclusion
Comments & Questions

4. Introduction Microalgae Base of aquatic food chain Variable uses
Plants similarities
Variable uses
Food industry
Bioremediation
Bioproducts
Biofuels
Variety of aquatic environments
Different microalgae metal profile

5. Introduction Biochemical and mineral content
Elements uptake for growth (bioaccumulation)
Cell Adsorption (biosorption)
Influence in microalgae use
Marine Microalgae for biodiesel
Lipids and fatty acid productivity (↑)
Replace diesel, petroleum, natural gas and coal
More resistance to environmental changes
Large seawater availability
Do not compete with crops

6. Objetives
Determine 26 chemical elements found in the biomass of marine microalgae, with potential to produce biodiesel, mainly by direct conversion of the biomass into biofuel;
Identify promising species, regarding their chemical element profile;
Find relations between taxonomic group and biosorption or bioaccumulation ability of species;
Find relations between biomass elements content and cultivation medium;

7. Microalgae cultivation and sampling;
Experimental Methods
Microalgae cultivation and sampling;
Light microscopy;
Biomass digestion;
ICP-OES analysis;
Chemometric analysis.

8. Microalgae cultivation medium (Conway)
Microalgae Species
(No floculant; no washing process; lyophilization)
Cyanobacteria
Aphanothece sp.
Planktolyngbia limnetica
Planktothrix isothrix
Romeria gracilis
Synechococcus sp.(1)
Synechococcus sp. (2)
Synechococcus sp.(3)
Synechocystis aquatilis (1)
Synechocystis aquatilis (2)
Synechocystis aquatilis (3)
Synechocystis sp. (1)
Synechocystis sp. (2)
Chlorophyceae
Chlorophyceae N. I. (1)
Chlorophyceae N. I. (2)
Chlorophyceae N. I. (3)
Dynoflagellate
Amphidinium carterae
Diatom
Achnanthes sp. (1)
Achnanthes sp. (2)
Amphora sp. (1)
Amphora sp. (2)
Biddulphia sp.
Biddulphia sp. cf longicruris
Biddulphia sp. cf. aurita
Chaetoceros simplex
Cylindrotheca closterium (1)
Cylindrotheca closterium (2)
Diatom N. I.
Entomoneis alata
Navicula sp. (1)
Navicula sp. (2)
Navicula sp (3)
Phaeodactylum tricornutum
Thalassiosira sp. (1)
Thalassiosira sp. (2)
Thalassiosira sp. (3)
Thalassiosira sp. (4)

9. Light Microscopy Biomass Digestion Samples selected at random;
100 mg biomass
Digestor
Volumetric Flask 25 mL
Precipitate in Eppendorf
Solution in Bottles
3 mL HNO3 70% metal ultrapure
Programação
S1: 330W – 5’
S2: 800W – 8’
S3: - 0W – 7’
Samples selected at random;
Zeiss Optics Microscope, model Axioskop2 – triocular;
Dryed biomass and rehydrated biomass with 0,85% NaCl solution.
Image capture of both conditions.

10. Chemical Elements Analysis by ICP-OES
ICP-OES Thermo Fisher Scientific model iCAP 6300
Calibration curve - 8 standard
LOD and LOQ calculated
Parameter
Condition
Auxiliary gas (argon)
0,5 L/min
Radiofrequency (RF) Power
1250 W
Pump rate
50 RPM
Nebulizer gas (argon)
0,18 MPa

11. Chemical Elements Analysis by ICP-OES
Emission Lines (nm)

12. Chemometric Analysis
PCA performed on Octave v Software for Windows;
Data autoescaled
Correlation Analysis performed on Microsoft Excel 2010, with suplement Data Analysis.

13. Results and Discussion
Method
LOQs (0,04 to 2,64, except Bi, Na and P >5,9 mg/Kg)
r (0,99813 a 0,99999)
Sensitivity and Linearity
 Analysis time
Chemical elements profile
Cellular affinity
Seawater quality

14. Results and Discussion

15. Results and Discussion
Adicionado
Quantificado Al X B Ba Be Bi Ca Cd Co Cr Cu Fe K Li Mg Mn Mo Na Ni P Pb Sn Sr Ti Tl V Zn
Results and Discussion
Microalgae as bioremediators
Bioindicators of contamined environments?
Water analysis x Microalgae analysis
Presence x Quantity

16. Results and Discussion
Range:
12,9 a 36,3%
Same gender
Na:
50 a 88%
Strains:
Amphora sp. (1)
Biddulphia sp.
Navicula sp. (3)
P.limnetica
Synechococcs sp. (1)

17. Results and Discussion
Cristals whithin the cels
Pearson’s correlation coeficients
Fe-Ti 0,96
Fe-Al 0,86
Al-Ti 0,85
Al-P 0,75
B-Mg 0,73
P-Pb 0,72
Ni-V 0,70
Na-P -0,71

18. Conclusions
Microalgae biomass showed high inorganic content for a biodiesel production feedstock, (12.9% to 36.3% mass of analyzed elements per dry biomass);
Then the use of microalgae as bioindicators of contaminated environments is indicated;
Navicula species showed toxic elements in their biomasses, such as Ba and Pb, which point their use in wastewater treatment;
most of the microalgae elements profiled were macroelements, Na >> Mg > K ≥ Ca > P, which are natural seawater components.

19. Questions?

20. Contact: Bruna Ferreira Silva
Thank You!
Agradecimentos
Contact: Bruna Ferreira Silva