Monday, April 19, 2010
LL Conference Facility (Hilton Clearwater Beach)
Microalgae are a promising source of carbon neutral and renewable biofuels due to their advantages of higher photosynthetic efficiency, higher biomass production and faster growth compared to other energy crops. Chlorella vulgaris has been considered as a potential raw material for bioethanol production because it can accumulate high starch content in its biomass.
The overall objective of this work was to compare selected methodologies for starch determination in C. vulgaris. Two methods were based on starch extraction with perchloric acid, and the other one consisted in using starch-digesting enzymes. The colorimetric reagent used for both perchloric acid methods was anthrone.
Microalgae were cultivated at 30ºC in 0.5 L photobioreactors containing a working volume of 0.4 L. Light intensity was approximately 100 µmol m-2 s-1 at the surface of the photobioreactor. The growth medium based on the elementary composition of algal biomass had the following initial composition (mg L−1): 1,100 (NH2)2CO, 237 KH2PO4, 204 MgSO4·7H2O, 40 C10H12O8N2NaFe, 88 CaCl2, 0.83 H3BO3, 0.95 CuSO4·5H2O, 3.3 MnCl2·4H2O, 0.17 (NH4)6Mo7O24·4H2O, 2.7 ZnSO4·7H2O, 0.6 CoSO4·7H2O and 0.014 NH4VO3 in distilled water.
Starch content in C. vulgaris determined by perchloric acid methods did not show significant differences with that obtained by the α-amylase-amyloglucosidase method.
It was concluded that the method using 30% HClO4 during 15 min at 25ºC can be considered as a reliable and shortened procedure suitable for the rapid measurement of starch content in C. vulgaris.
The overall objective of this work was to compare selected methodologies for starch determination in C. vulgaris. Two methods were based on starch extraction with perchloric acid, and the other one consisted in using starch-digesting enzymes. The colorimetric reagent used for both perchloric acid methods was anthrone.
Microalgae were cultivated at 30ºC in 0.5 L photobioreactors containing a working volume of 0.4 L. Light intensity was approximately 100 µmol m-2 s-1 at the surface of the photobioreactor. The growth medium based on the elementary composition of algal biomass had the following initial composition (mg L−1): 1,100 (NH2)2CO, 237 KH2PO4, 204 MgSO4·7H2O, 40 C10H12O8N2NaFe, 88 CaCl2, 0.83 H3BO3, 0.95 CuSO4·5H2O, 3.3 MnCl2·4H2O, 0.17 (NH4)6Mo7O24·4H2O, 2.7 ZnSO4·7H2O, 0.6 CoSO4·7H2O and 0.014 NH4VO3 in distilled water.
Starch content in C. vulgaris determined by perchloric acid methods did not show significant differences with that obtained by the α-amylase-amyloglucosidase method.
It was concluded that the method using 30% HClO4 during 15 min at 25ºC can be considered as a reliable and shortened procedure suitable for the rapid measurement of starch content in C. vulgaris.