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Optimization of the sonication extraction method of Hibiscus tiliaceus L. flowers
Maria Inês Soares Melecchi1, Valéria Flores Péres, Cláudio Dariva
1Chemistry Institute, UFRGS, Porto Alegre, RS, av. Bento Gonçalves, 9500, CEP 91501-960, RS, Brazil.
Abstract:
The influence of several experimental parameters on the ultrasonic extraction of Hibiscus tiliaceus L. flowers were investigated: extraction time, solvent polarity, sample amount, solvent volume and sample particle size. It was concluded that the most influential variables were extraction time and solvent polarity. The optimized procedure employed 5 g of ground flowers, 150 mL of methanol and 140 min of extraction. The extracts were fractionated using preparative silica columns and the resulting fractions were analyzed by GC/MS. Some saturated hydrocarbons, fatty acids, fatty acid methyl esters, phytosterols, and vitamin E were identified in the plant extracts.

