Characterization and in vitro antiparasitic activities of plant extracts containing natural and modified proanthocyanidins

Iqbal Bin Imran

This dissertation focuses on proanthocyanidins (PAs) that are plant specialized metabolites with numerous industrial applications. The study investigated the susceptibility of natural PAs to modification by alkaline oxidation. The UHPLC-DAD-MS/MS method was used to analyze oxidized and non-oxidized PA-rich plant extracts from multiple plant species. The results revealed that the various structural features of PAs can be used to predict their susceptibility to oxidation. The orbitrap ultra-high-resolution tandem mass spectrometric analyses of the compounds revealed the complex structures and various reactions within the PA classes. The study also investigated the in vitro antiparasitic effects of various PA-rich extracts (original and oxidized) against Ascaris suum nematodes. The modifications of the PAs in the plant extracts significantly increased their antiparasitic activity. The study provides insights on how plant PAs can be chemically modified to create novel industrial and pharmaceutical products.

Overall, the oxidation of PAs is important in many plant-related research areas, such as ecology, physiology, food, feed, and medicine. Understanding this process allows us to get vital insights that will enrich these domains and pave the way for future research. Furthermore, the rapid and simple oxidation procedure enables large-scale production of modified PAs, which can be studied to determine their potential application in developing novel anthelmintic drugs.