Investigation of dynamic accumulation and regularity of nine glycosides and saccharides in Rehmannia glutinosa by rapid quantitative analysis technology

Abstract

† These authors contributed equally to this work.In the process of planting and harvesting of Rehmannia glutinosa, only the underground part is used, and a large number of stems and leaves that are considered non-medicinal parts are usually discarded. Recent studies have shown that the chemical components in the leaves are similar to those identified in the roots. In this study, we selected leaves and roots from Rehmannia glutinosa at different growth stages and leaves from different cultivation regions to investigate the dynamic accumulation of three kinds of glycosides (catalpol, acteoside, and ajugol), six kinds of carbohydrates (rhamnose, fructose, sucrose, melibiose, stachyose, and verbascose), and acidic and neutral polysaccharides via rapid quantitative analysis technology, including ultra high performance liquid chromatography triple quadrupole tandem mass spectrometry, high-performance liquid chromatography, and UV spectroscopy. The results showed that the Rehmannia glutinosa leaves also contained higher content of catalpol (3.81∼24.51 mg/g), ajugol (0.55∼10.23 mg/g), acteoside (1.34∼21.16 mg/g), monosaccharide/ oligosaccharides (7.71∼120.73 mg/g), and polysaccharides (5.63∼15.57%). In this study, we developed a new rapid and simple method for determination to clarify the distribution and dynamic accumulation of nine glycosides and saccharides in Rehmannia glutinosa leaves to provide a scientific basis for the discovery, development, and utilization of the resource value of Rehmannia glutinosa leaves.

Optimisation for simultaneous determination of iridoid glycosides and oligosaccharides in Radix Rehmannia by microwave assisted extraction and HILIC‐UHPLC‐TQ‐MS/MS

“…Our results indicated ajugol, catalpol, sucrose, raffinose and stachyose as important discriminators between crude and processed Radix Rehmanniae. These components may be responsible for the differing therapeutic effects of crude and processed Radix Rehmanniae and therefore could be used as quality markers of Radix Rehmanniae …”

“…Reversed‐phase high‐performance liquid chromatography (RP‐HPLC) with ultraviolet (UV) and mass spectrometry (MS) detection have been developed for the determination of iridoid glycosides in Radix Rehmanniae . Due to the high hydrophilicity and lack of chromophore and fluorophore groups in the structures, analysis of oligosaccharides using the earlier‐mentioned methods always encounters great difficulty.…”

“…In view of this, Xu et al . developed two separate methods to determine glycosides by ultra‐high‐performance liquid chromatography (UHPLC)‐TQ‐MS/MS and saccharides by HPLC‐ELSD in Radix Rehmanniae …”

“…Reversed-phase high-performance liquid chromatography (RP-HPLC) with ultraviolet (UV) and mass spectrometry (MS) detection have been developed for the determination of iridoid glycosides in Radix Rehmanniae. [7][8][9] Due to the high hydrophilicity and lack of chromophore and fluorophore groups in the structures, analysis of oligosaccharides using the earlier-mentioned methods always encounters great difficulty. Hydrophilic interaction liquid chromatography (HILIC) is a method of choice for the separation of oligosaccharides by providing specific retention of highly hydrophilic compounds that are usually poorly retained in RP-HPLC.…”

“…8 Sample preparation is often the rate-limiting step in the overall analysis process. It was reported that extraction of iridoid glycosides and oligosaccharides from Radix Rehmanniae was usually achieved by ultrasonic extraction with an extraction time of 1-3 h. 8,13 As an efficient and widely used extraction technique, microwave-assisted extraction (MAE) offers much shorter extraction time, less solvent consumption, higher extraction efficiency and sample throughput than ultrasonic extraction. 14,15 Up to now, the use of MAE for the extraction of iridoid glycosides and oligosaccharides from Radix Rehmanniae has not been reported.…”