The use of ultrasound in the extraction of Ilex paraguariensis leaves: A comparison with maceration

Chemistry Institute, UFRGS, Porto Alegre, av. Bento Gonçalves, 9500, CEP: 91501-960 RS, Brazil.
Ultrasonics Sonochemistry (Impact Factor: 3.82). 02/2007; 14(1):6-12. DOI: 10.1016/j.ultsonch.2005.11.007
Source: PubMed

ABSTRACT The objective of this work is to discuss the main parameters that influence the sonication extraction of Ilex paraguariensis leaves. For this purpose, the extraction time, solvent polarity, solvent volume, sample mass and particle size were evaluated. Results showed that the main variable affecting the extraction process was the solvent polarity. Though in a less extent, temperature and extraction time also demonstrated to be important parameters, while the other variables did not present a significant influence on the extraction yield. The extracts at the optimized condition were compared with those obtained by maceration, in terms of mass yield and chemical composition. The major compounds identified in the extracts were caffeine and palmitic acid. Some saturated hydrocarbons such as fatty acids, fatty acid methyl esters, phytosterols, and theobromine were also identified in the fractions.

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