Estudo da qualidade e da foto-degradação dos óleos essenciais comerciais de capim limão (Cymbopogon citratus)

Abstract

In order to evaluate the quality of Lemongrass (Cymbopogon citratus) essential oils available in the national market, related to their photodegradation, or their preparation mode and storage conditions, we sought to conduct laboratory tests, checking the results of their respective physicochemical characteristics. Essential oils are compounds provided with terpenes and several other components that in presence of light and temperature, they react, degrading, losing their major components that provide the main sensory and physical characteristics of the oil. Were acquired 6 random samples, obtained in different regions of the national market. The samples were subjected to characterization tests (relative density, refractive index, UV - VIS and GC/MS spectrometry) as well as a standard sample for comparison, extracted and stored under appropriate conditions at the Federal Technological University of Paraná - Toledo campus. A large discrepancy was observed in samples 2, 3, 4 and 6, having low refractive index and high density, and chemicals composition of these oils when compared with that described in the literature. The samples 2, 3, 4, 5 and 6 were out of the ideal standards for these constituents. The sample 1, together with the standard sample, were within the standards reported in medical literature, being closer to the purity specification, containing 0,929 and 0,922 of density, 1,488 and 1,487 of refractive index respectively to sample 1 and standard sample. To major constituents was found 39,42% of Neral and 50,49 of Geranial, to sample 1, to standard sample was found 32,93% of Neral and 43,94% of Geranial. With the present study was evident despite the differences in the composition of the essential oil as well as its instability to the light , a form of proper packaging is required , avoiding his descaracterization.