Liquid Chromatography-Mass Spectrometry-Guided Isolation of Bioactive Solvent Fractions Derived from Oyster (Magallana Bilineata) PowderResidue

Introduction: The slipper-shaped oyster Magallana bilineata, a species commonly farmed in the Philippines, is being processed into oyster extract powder, a shelf-stable product that can be easily incorporated into various food applications. Oyster powder residue, a byproduct of oyster extract processing, is rich in essential amino acids and proteins. Our innovative study, which is the first of its kind, focuses on the potential bioactivity of M. bilineata residue, a promising novel metabolite source with significant biomedical applications. Methods: Our approach, which included solvent extraction, fractionation by octadecyl-silica (ODS) column chromatography, and liquid chromatography-mass spectrometry (LC-MS)-guided profiling of the active fractions, was meticulously designed to be robust and reliable. The crude and active fractions, including those with antimicrobial, antioxidant, and cytotoxic activities, were rigorously studied in bioactivity assays, further ensuring the reliability of our findings. Results: The results indicated that the solvent fractions of oyster M. bilineata residue may contain several bioactive compounds, such as alkaloids, terpenoids, peptides, and cytotoxic macrolides, which are responsible for their notable biological activities. The 80% methanol fraction exhibited better anticancer activity against MCF-7 human breast cancer cells, with an IC50 value of 58.77 ± 1.26 µg/mL, compared to the positive control, cisplatin (97.56 ± 0.31 µg/mL). Moreover, the fractions also exhibited strong antibacterial activities against some pathogenic microorganisms and showed scavenging activity against the diphenyl-1-picrylhydrazyl (DPPH) radical. Discussion: The significant bioactive characteristics exhibited by the methanol fractions may be due to the existence and availability of the essential chemical components within each fraction. Oysters, as filter feeders, can accumulate bioactive compounds from their environment as they actively filter water by absorbing and concentrating a variety of substances, including biologically active ones. Conclusion: Our study has demonstrated the competency of LC-MS profiling in conjunction with bioassays in identifying bioactive components in oyster powder residue. This approach offers a reliable and promising perspective on utilizing waste from oyster processing as a rich and untapped source of bioactive compounds with significant pharmaceutical potential, opening new avenues for research and application.