Extração e separação do carotenoide luteína através da cromatografia líquida de alta eficiência

Abstract

Chemistry contributes to the production of numerous fundamental products for humanity, and currently, the production of these compounds takes environmental sustainability into account, that is, it aims to use techniques and methodologies that reduce or eliminate the use of solvents, reagents, or the generation of by-products harmful to human health or the environment. Among these compounds are the carotenoids, a group of pigments that plays a fundamental role in human health, being able to highlight their effect on the immune response, intracellular communication, and the fight against diseases related to aging. Emphasis should be given to lutein, a carotenoid presents in fruits and vegetables that is used in the food industry as a dye and has a potential biological activity in the prevention of cancer, cardiovascular disease, and retinal degeneration. The natural industrial source of this carotenoid is the flowers of the marigold (Tagetes erecta L.) that have low lutein content. One of the sources for obtaining lutein and several other carotenoids are microalgae, organisms with great biotechnology potential that can be grown in controlled environments or open tanks in the presence of sunlight or artificial light. To obtain lutein through microalgae it is necessary to promote an extraction by breaking the cell wall, followed by purification. The most used extraction method is solvent extraction and because carotenoids are fat-soluble, it is common to carry out saponification to remove lipids that may interfere with their extraction with nonpolar solvents. After extraction, carotenoids are separated by high-performance liquid chromatography (HPLC). Given the health benefits of lutein, associated with the potential of microalgae in the production of this carotenoid, the present project studies analytical methodologies reported in the literature for extracting lutein from microalgae. The methodologies studied involve three crucial processes: cell disruption, saponification, and extraction with an organic solvent. The methods presented by Ceron et al. (2008) and Utomo et al. (2008) report that cell disruption performed through milling results in the best lutein recovery. The saponification procedure often used in the reported studies applies an alkaline agent, such as KOH, in methanolic or ethanolic solution, and Soares et al. (2016) note that the saponification step in ethanolic solution prior to lutein extraction, offers simplification of the chromatographic profile obtained for the carotenoid mixture.