Sustainable agriceuticals: Alkaline solubilization and acid precipitation (ASAP) effectively isolate mangosteen pericarps xanthones with high bioactivity

Fruit peels and seeds, like those of mangosteen, are agricultural wastes but are rich in bioactive secondary metabolites such as polyphenolic compounds, which are highly valuable for functional food ingredients. However, the current industrial extraction processes for these compounds rely heavily on organic solvents, which are neither cost-effective nor environmentally friendly. To address these issues, an organic solvent-free method called alkaline solubilization and acid precipitation (ASAP) was developed for extracting xanthones from mangosteen pericarp. Chemical composition analysis using 1 H NMR and HPLC revealed that the ASAP extract (MP-P) could isolate α-mangostin close to 90 percent (89.94 %) purity, compared to 33.91 % by conventional organic solvent extract (MP-O) and only 0.39 % in the DI water extract (MP-W). Furthermore, garcinone D, γ-mangostin, 8-deoxygartanin and 9-hydroxycalabaxanthone were also successfully obtained using the ASAP extraction method. Additionally, MP-P exhibited superior pancreatic α-amylase inhibition activity and anti-inflammatory effects in the RAW 264.7 cell model relative to MP-O and MP-W. Our method makes it possible to reclaim xanthones from mangosteen pericarps in a green and cost-effective manner. • Solvent-free ASAP method enables green xanthones extraction from mangosteen pericarps. • ASAP method achieved α-mangostin extraction with 89.94 % purity. • MP-P shows higher α-amylase inhibition activity than solvent-based extracts. • MP-P exhibits superior anti-inflammatory effects in RAW 264.7 cells over MP-O and MP-W.