Dereplication of Natural Products Using Mass Spectrometry Integrated Approach

Abstract

Plant metabolites can act as drugs for the treatment of a variety of diseases due to their unique skeletal features. A large number of plant metabolites are used as drugs for the treatment of many diseases. The structural diversity of these plant metabolites formed by complex enzymatically controlled pathways is still not fully explored. Moreover, to preserve the medicinally important plant species and their sustainability, the quantity of plant material has been limited to the analytical level. Therefore, sensitive and high-throughput dereplication methods are required for better, unambiguous and high-throughput analysis of natural products in complex mixtures. We have developed a high-throughput dereplication strategy for the unambiguous identification of different classes of natural products through LC-ESI-MS/MS in plant extract and in herbal formulations using an integrated approach which includes several confirmatory steps such as exact masses measurement, diagnostic fragment ions, database search, and isotopic pattern. Based on this integrated approach, we have recently investigated different classes of natural products including withanolides (steroidal lactones), pregnane-type steroidal alkaloids, Buxus steroidal alkaloids and many more by using electrospray ionization quadrupole time-of-flight mass spectrometry (ESI-QTOF-MS/MS) and LC-QQQ-MS analysis. Moreover, we have also developed a LC-ESI-MS/MS database of unique natural products.