Chromenes from Ageratum conyzoides: Steam distillation, supercritical extraction, and mathematical modeling

ABSTRACT

The chromenes extraction processes from Ageratum conyzoides by steam distillation and supercritical fluid extraction (SFE) were studied. Essential oil was extracted by saturated steam at 1.0 to 2.0 bar and the SFE was performed at 40ºC and 90 to 200 bar to obtain non-volatile extracts. The essential oil presented two major compounds—precocene I (28.24%) and precocene II (28.55%). At 90 bar, the SFE resulted in higher yield and selectivity for precocene I and II (65.06%). The yield of chromenes varied according to pressure of SFE; however, this behavior was not observed in extracts obtained by steam distillation.

KEYWORDS:

• Precocene
• mass transfer
• HPLC analysis
• GC-MS analysis
• extraction kinetics

Acknowledgements

The authors wish to thank G.V. Ccana-Ccapatinta and S. Kaiser for HPLC support.