Rapid Identification of Common Secondary Metabolites of Medicinal Herbs Using High-Performance Liquid Chromatography with Evaporative Light Scattering Detector in Extracts.

Kiran Ali,Saeedur Rahman,Muhammad Noman Khan,Shaheen Faizi,Shaden A M Khalifa,Muhammad Shaiq Ali,Arslan Ali,Hesham R El-Seedi,Syed Ghulam Musharraf

doi:10.3390/metabo11080489

Abstract

The discovery and identification of novel natural products of medicinal importance in the herbal medicine industry becomes a challenge. The complexity of this process can be reduced by dereplication strategies. The current study includes a method based on high-performance liquid chromatography (HPLC), using the evaporative light scattering detector (ELSD) to identify the 12 most common secondary metabolites in plant extracts. Twelve compounds including rutin, taxifolin, quercetin, apigenin, kaempferol, betulinic acid, oleanolic acid, betulin, lupeol, stigmasterol, and β-sitosterol were analyzed simultaneously. The polarity of the compounds varied greatly from highly polar (flavonoids) to non-polar (triterpenes and sterols). This method was also tested for HPLC-DAD and HPLC-ESI-MS/MS analysis. Oleanolic acid and ursolic acid could not be separated in HPLC-ELSD analysis but were differentiated using LC-ESI-MS/MS analysis due to different fragment ions. The regression values (R2 > 0.996) showed good linearity in the range of 50–1000 µg/mL for all compounds. The range of LOD and LOQ values were 7.76–38.30 µg/mL and 23.52–116.06 µg/mL, respectively. %RSD and % trueness values of inter and intraday studies were mostly <10%. This method was applied on 10 species of medicinal plants. The dereplication strategy has the potential to facilitate and shorten the identification process of common secondary metabolites in complex plant extracts.

Highlights

Licensee MDPI, Basel, Switzerland.Herbal products have proven effective for the treatment of various diseases since ancient times and are still a major interest of researchers [1–3]
Employing a screening analysis can be very useful. This is carried out using dereplication, a procedure that helps in the recognition of reported compounds at an early stage, making it easier to discriminate peaks of known compounds from the peaks of interest
We have developed a high-performance liquid chromatography by means of the evaporative light scattering detector (HPLC-ELSD) method for the rapid identification of the most common plant-derived secondary metabolites of both polar and non-polar nature applying the same gradient

Summary

Introduction

Herbal products have proven effective for the treatment of various diseases since ancient times and are still a major interest of researchers [1–3]. This is due to diverse bioactivities of the natural products and their potential as drug leads [1,4–6]. Many of the synthetic drugs have been designed by mimicking the unique structures of natural products, imparting their pharmaceutical properties [1,7,8]. Employing a screening analysis can be very useful. This is carried out using dereplication, a procedure that helps in the recognition of reported compounds at an early stage, making it easier to discriminate peaks of known compounds from the peaks of interest

Methods

Results

Conclusion