Carotenoids are important pigments that presents several applications in pharmaceutical, cosmetic and food industries either as colorants or antioxidants. However their extraction is performed with solvents such as hexane, methanol and ethyl acetate depending on the polarity of the carotenoid to be extracted, causing an environmental and health impact. Due to these disadvantages, alternative extraction techniques have been searched such as supercritical fluids, mainly CO2, because is a gas with low environmental impact, because of its gaseous state it can permeate better the cell wall and cell membrane than organic solvents; thus improving the amount of carotenoid extracted. In this research carotenoids from marine actinobacteria Gordonia sp. were extracted with solvents (a mixture of dichloromethane:methanol:acetone) and with supercritical CO2 followed by their characterization and quantification with FT-IR, NMR, HPLC-DAD at 450 nm and ESI-MS, antioxidant activity against radical DPPH was also evaluated in both extracts using HPLC-DAD at 517 nm. It can be seen in the FT-IR spectra as well as in the chromatograms of both extracts that they present the same signals regarding FT-IR and the same compounds in the case of HPLC-DAD where it can be seen also in the chromatogram that the amount of carotenoids increased from 1.80 mcg/mL with solvent extraction to 3.36 mcg/mL when extracted with supercritical CO2 . The maximum absorption at 475,470 and 465 nm in the three compounds detected allow to demonstrate the presence of carbonyl groups within the molecule. The NMR signals correspond probably to carotenoids with glycosidic bonds, while the ESI-MS allowed the determination of astacen glycosides derivatives. Supercritical CO2 extract presented a better antioxidant activity (52.97%) than the solvent extract (36.34%). Extraction with supercritical CO2 allowed to improve the carotenoid content, as well as the antioxidant activity of the pigment.

Extracción de carotenoides microbianos con CO2 supercrítico

LatinXChem

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.