Prospective pathway for a green and enhanced friedelin production through supercritical fluid extraction of Quercus cerris cork

authors	Sen, A; de Melo, MMR; Silvestre, AJD; Pereira, H; Silva, CM
nationality	International
journal	JOURNAL OF SUPERCRITICAL FLUIDS
author keywords	Cork; Friedelin; Modeling; Quercus cerris; Supercritical fluid extraction
keywords	EUCALYPTUS-GLOBULUS BARK; RESPONSE-SURFACE METHODOLOGY; TRITERPENIC ACIDS; CHEMICAL-COMPOSITION; CARBON-DIOXIDE; BY-PRODUCTS; EXPERIMENTAL-DESIGN; SUBER L.; CO2; OPTIMIZATION
abstract	Supercritical fluid extraction (SFE) was applied for the first time to Quercus cerris cork, and compared with Soxhlet with dichloromethane (DCM). Novel triterpenes, viz. betulin and squalene, and beta-sitosterol were identified for the first time in the lipophilic extracts. The SFE at 300 bar and 40-80 degrees C provided extracts much richer in friedelin-the major compound from both SFE and DCM extracts - with concentrations up to 40.6 wt%, against 26.0 wt% for DCM. The SFE yields ranged between 0.97 and 1.81 wt% with pure CO2, and attained 2.83 wt% when ethanol was introduced as cosolvent (10 wt%). In this case, however, the friedelin concentration dropped significantly due to the additional removal of non-target compounds. In general, the experimental data and their trends were in accordance with the theoretical predictions of kinetic and equilibrium properties estimated in this work for the friedelin/SC-CO2 system. This study demonstrates that the SFE of Q cerris cork arises as a prospective pathway for a green and enhanced friedelin production process under the biorefinery concept. (C) 2014 Elsevier B.V. All rights reserved.
publisher	ELSEVIER SCIENCE BV
issn	0896-8446
year published	2015
volume	97
beginning page	247
ending page	255
digital object identifier (doi)	10.1016/j.supflu.2014.12.008
web of science category	Chemistry, Physical; Engineering, Chemical
subject category	Chemistry; Engineering
unique article identifier	WOS:000348952800029