Extraction Of Natural Pigments From Gardenia Jasminoides J.Ellis Fruit Pulp Using Co2-Expanded Liquids And Direct Sonication

In this work, a carbon dioxide-expanded liquid (CXL) extraction system was used with or without direct sonication for the extraction of highly polar natural pigments (crocin-1 and crocin-2) from Gardenia jasminoides Ellis fruit pulp. The effects of different parameters, including modifiers (ethanol, water, aqueous ethanol), temperature (5-25 degrees C), pressure (8-14 MPa), and sonication time (0-200 s) on extraction concentrations were examined using the CXL system. Aqueous ethanol (50% or 80%, v/v) was selected for the CXL system as a modifier due to its efficiency. The best conditions for extraction were found at 25 degrees C and 10 MPa. The CXE 80% extraction system with direct sonication extracted a significantly higher amount of crocin-1 and crocin-2, 13.63 +/- 0.5 and 0.51 +/- 0.05 mu g/mL, respectively, compared to conventional solid-liquid methanol extraction (10.43 +/- 0.3 and 0.37 +/- 0.02 mu g/mL, respectively). Under these conditions, a water-rich phase, an ethanol-rich phase, and a CO2-rich gas phase coexisted in the high-pressure cell in the CXE 80% extraction system, which was vigorously disrupted by the addition of sonication, resulting in a compressed aqueous ethanol phase and an aqueous ethanol-modified CO2-rich phase, and may have a positive influence on extraction.