Isolation and Structure Elucidation of a New Diterpene Glycoside from Stevia rebaudiana Bertoni

Venkata Sai Prakash Chaturvedula,Srinivasa Rao Meneni

doi:10.5539/jfr.v7n1p70

Abstract

A new minor diterpene glycoside has been isolated from a commercial extract of the leaves of Stevia rebaudiana and its structure was identified as 13-[(2-O-β-D-glucopyranosyl-β-D-glucopyranosyl)oxy] ent-kaur-16-en-19-oic acid-[2-O-(2-O-β-D-glucopyranosyl)-β-D-glucopyranosyl-3-O-b-D-glucopyranosyl-β-D-glucopyranosyl] ester (1) based on extensive NMR (1D and 2D) and mass spectroscopic data, and hydrolysis studies.

Highlights

Recent interest of food and beverage industry towards reduction in calories by introducing natural non-caloric sweeteners into their systems together with the increasing awareness of obesity problem and the health impacts associated with certain artificial sweeteners has driven research focus towards natural high-potency sweeteners
Purification of the commercial extract from the leaves of S. rebaudiana obtained from SinoChem Qingdao Co Ltd, China resulted in the isolation of an additional new diterpenoid glycoside 1 and its structure elucidation has been deduced based on the 1D (1H and 13C NMR), and 2D NMR spectral assignments (TOCSY, HSQC, HMBC) as well as enzymatic and acid hydrolysis studies
The structure elucidation of the novel compound was further supported by high resolution mass spectral data (HRMS), and MS/MS data and hydrolysis studies

Summary

Introduction

Recent interest of food and beverage industry towards reduction in calories by introducing natural non-caloric sweeteners into their systems together with the increasing awareness of obesity problem and the health impacts associated with certain artificial sweeteners has driven research focus towards natural high-potency sweeteners. Stevia rebaudiana (Bertoni) Bertoni, a perennial shrub often referred to as “the sweet Herb of Paraguay” (Mosettig et al, 1963; Mosettig & Nes, 1955) belong to the Asteraceae (Compositae) have been used for decades to sweeten food and beverages in Japan, South America and China. Due to increase in demand for pure steviol glycosides, it is grown commercially in several countries, in Japan, Taiwan, Korea, Thailand and Indonesia. As a part of our continuing research to discover natural sweeteners from the leaves of S. rebaudiana, we have obtained commercial extracts from various suppliers around the World and isolated various new steviol glycosides (Chaturvedula & Zamora, 2014; Chaturvedula 2014; Chaturvedula & Meneni 2016, 2017)

Methods

Results

Conclusion