A Critical Cross-Species Comparison of Pollen from Nelumbo nucifera Gaertn. vs. Nymphaea lotus L. for Authentication of Thai Medicinal Herbal Tea.

Duangjai Tungmunnithum,Jean-Philippe Blondeau,Samantha Drouet,Sullivan Renouard,Christophe Hano

doi:10.3390/plants9070921

Abstract

“Bau Luang” or Nelumbo nucifera Gaertn. is an aquatic medicinal herb that has been used as a component of traditional medicines, medicinal products, and herbal tea for good health, particularly in Asia. The stamen of N. nucifera is an important part of this medicinal plant that is used in the form of dried and/or powdered stamens for herbal tea as well as the main ingredient of some traditional remedies. However, there is another aquatic herb called “Bau Sai” or Nymphaea lotus L. that is distributed in similar locations. Living plants of these two aquatic species may be classified according to their morphology, but the dried and powdered stamens of these two medicinal species are difficult to distinguish. The major reason of adulteration is the higher price of Bau Luang stamen. As a result, various methods of authentication, such as pollen micromorphology evaluation using scanning electron microscopy (SEM) analysis, bioinformatics analysis of two nuclear and plastic DNA markers, phytochemical stamen profiling, and Fourier transform infrared (FTIR) analysis of stamen plant material authentication from Bau Luang and Bau Sai, have been used in this present research in order to avoid some adulteration and/or misuse between the dried stamens of Bau Luang and Bau Sai. These results showed that the micro-morphology of pollen (size of pollen grain, number of apertures, and surface ornamentation) from the SEM analysis, some phytochemical compounds and the FTIR sporopollenin-to-protein ratio signal analysis are potential tools for authentication and identification of these two medicinal plants from their dried-stamen materials. This model of investigation may also be used to distinguish dried plant material from other problematic plant groups.

Highlights

The stamen of Nelumbo nucifera Gaertn. is one of the important ingredients of traditional medicines in Asian countries, e.g., China, Thailand, Japan, and India
Authentication methods are needed to clearly authenticate dried plant material from these two medicinal plant species. This present study aims to evaluate different botanical, molecular, and chemical approaches to propose some effective tools for the authentication the dried plant material from these two species using their stamens
The chalcones have already shown their usefulness in establishing evolutionary and systematic connections between plants [22], so we propose that the chalcononaringenin derivative detected here in the N. lotus could be the preferred authentication marker

Summary

Introduction

The stamen of Nelumbo nucifera Gaertn. is one of the important ingredients of traditional medicines in Asian countries, e.g., China, Thailand, Japan, and India. Is one of the important ingredients of traditional medicines in Asian countries, e.g., China, Thailand, Japan, and India. It has been used as an herbal tea for health benefits including boosting the body’s immune system and improving circulation. According to the lack of research on the bioactive molecule and the pharmacological activity and safety of “Bau Sai,” there are no herbal teas made from this species in the market. These two aquatic medicinal plants can be distinguished by the morphological characteristics of living plants. Dried specimens of these medicinal herbs ( the stamens) are difficult to distinguish

Methods

Results

Conclusion