Brazilian green propolis extracts obtained by conventional processes and by processes at high pressure with supercritical carbon dioxide, ethanol and water

- Green propolis extracts were obtained by conventional and by high pressure processes.
- There were obtained Artepillin C enriched extracts.
- The best yields of phenolics compounds were obtained using scCO2 with co-solvent.
- All extracts showed high antioxidant activity.

Extracts of green propolis were obtained by conventional process at atmospheric pressure and at high pressure using supercritical carbon dioxide (scCO2) as solvent and, ethanol and water and its mixtures as solvents or as CO2 co-solvents. All extracts were evaluated with regards to the total phenol content, total flavonoids, Artepillin C, p-Coumaric Acid and Kaempferide and also was evaluated the antioxidant activity, and in vitro antimicrobial activity. The highest overall extraction yields were 53.5% in the three-step sequential extraction at high pressure and 44.7% at low pressure in a Soxhlet extractor. All extracts showed high antioxidant activity and presented antimicrobial activity. The highest levels of phenols of 222 mg GAE/g extract, of flavonoids of 67.0 mg CE/g extract, of artepillin C of 62.4 mg Artepillin C/g extract and high antioxidant activity were obtained in the ethanolic extract (80%) of the second stage of the two-step sequential process.

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