Presence of Acetogenins in Starches and Pectins Extracted from Soursop (Annona muricata L.) Fruits

Acetogenins are lipidic polyketides with antioxidant, antimicrobial, cytotoxic, and antitumor properties, mainly found in the roots, stems, bark, leaves, and fruits (particularly the seeds) of Annonaceae species. Previous studies have identified acetogenins in the peel and pulp of soursop (Annona muricata L.) fruits. In this research, acetogenins present in starch and pectin extracted from these fruits were analyzed and identified, given their potential importance in the pharmaceutical and possibly in the food industries. The objective was to identify and quantify acetogenins in starch and pectin of soursop fruits. Extraction of both polysaccharides was performed using conventional and ultrasound-assisted methods, obtaining two types of pastes (white and brown). These were characterized by Fourier Transform Infrared Spectroscopy (FTIR). Methanolic extracts from the pastes were analyzed by thin-layer chromatography and open-column fractionation. Acetogenins were identified and quantified by high-performance liquid chromatography (HPLC). The compounds identified were pseudoannonacin and anonacin. In pectin, the concentration (μg g−1 of dry basis P/A) of pseudoannonacin was 340.06 (conventional) and 452.80 (ultrasound-assisted), while for anonacin it was 302.29 (conventional) and 397.23 (ultrasound-assisted). In starch, the concentration (μg g−1 of dry basis P/A) of pseudoannonacin was 20.72 (conventional) and 21.60 (ultrasound-assisted), whereas anonacin showed concentrations of 1.63 (conventional) and 3.12 (ultrasound-assisted). These results confirm the presence of anonacin and pseudoannonacin in both starch and pectin of soursop fruits, with pseudoannonacin being the most abundant acetogenin detected.