Multisolvent metabolite profiling of coffee waste by UHPLC-HRMS/MS and molecular networking.

Summary

Using UHPLC-HRMS/MS, GC-MS, multivariate statistics, and molecular networking, this study shows that solvent polarity and raw material origin (green beans vs spent grounds; Arabica vs Robusta) dictate recovery of specific bioactives from coffee waste. Non-polar solvents favor lipids/sterols (especially from SCG), while ethanol enriches hydrophilic antioxidants like chlorogenic acid from GB, providing a roadmap for sustainable cosmetic ingredient development.

Key Findings

• Non-polar solvents recovered fatty acids and sterols preferentially, especially from spent coffee grounds.
• Ethanol extracted higher levels of hydrophilic antioxidants, including chlorogenic acid, particularly from green beans.
• PCoA and Random Forest showed solvent polarity and material origin drive metabolite variation and classification.
• Molecular networking visualized structurally related metabolite clusters and solvent/material-associated distributions.

Clinical Implications

While preclinical, the workflow informs selection of sustainable extracts for cosmeceutical development (e.g., antioxidant-enriched vs lipid-rich fractions), streamlining safety and efficacy testing pipelines.

Limitations

• No direct bioactivity assays; cosmetic efficacy remains to be validated
• Limited to five solvents and specific Arabica/Robusta materials; generalizability to other wastes uncertain

Future Directions

Link chemical profiles to bioactivity and safety, standardize extraction protocols, and evaluate scalability and lifecycle impacts for cosmetic-grade ingredients.