Biorefining Brazilian Green Propolis: An Eco-Friendly Approach Based on a Sequential High-Pressure Extraction for Recovering High-Added-Value Compounds

Molecules. 2025 Jan 6;30(1):189. doi: 10.3390/molecules30010189.

Abstract

Propolis is a valuable natural resource for extracting various beneficial compounds. This study explores a sustainable extraction approach for Brazilian green propolis. First, supercritical fluid extraction (SFE) process parameters were optimized (co-solvent: 21.11% v/v CPME, and temperature: 60 °C) to maximize yield, total phenolic content (TPC), antioxidant capacity, and LOX (lipoxygenase) inhibitory activity. GC-MS analysis identified 40 metabolites in SFE extracts, including fatty acids, terpenoids, phenolics, and sterols. After selecting the optimum SFE process parameters, a sequential high-pressure extraction (HPE) approach was developed, comprising SFE, pressurized liquid extraction (PLE) with EtOH/H2O, and subcritical water extraction (SWE). This process was compared to a similar sequential extraction using low-pressure extractions (LPE) with a Soxhlet extractor. The HPE process achieved a significantly higher overall yield (80.86%) than LPE (71.43%). SFE showed higher selectivity, resulting in a lower carbohydrate content in the non-polar fraction, and PLE extracted nearly twice the protein amount of LPE-2. Despite the HPE selectivity, LPE extracts exhibited better acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and LOX inhibition, demonstrating that the neuroprotective and anti-inflammatory activity of the extracts may be associated with a symbiosis of a set of compounds. Finally, a comprehensive greenness assessment revealed that the HPE process proved more sustainable and aligned with green chemistry principles than the LPE method.

Keywords: bio-based solvent; environmental impact; natural products; phytochemicals; process optimization.

MeSH terms

  • Antioxidants* / chemistry
  • Antioxidants* / isolation & purification
  • Antioxidants* / pharmacology
  • Brazil
  • Chromatography, Supercritical Fluid* / methods
  • Gas Chromatography-Mass Spectrometry
  • Green Chemistry Technology
  • Lipoxygenase Inhibitors / chemistry
  • Lipoxygenase Inhibitors / isolation & purification
  • Lipoxygenase Inhibitors / pharmacology
  • Phenols / chemistry
  • Phenols / isolation & purification
  • Pressure
  • Propolis* / chemistry

Substances

  • Propolis
  • Antioxidants
  • Phenols
  • Lipoxygenase Inhibitors