Enhancement of stevioside production by using biotechnological approach in in vitro culture of Stevia rebaudiana

Meltem Bayraktar,Aynur Gürel,Bärbel Röck-Okuyucu,Fatih Karabey,Elmira Nazi̇ri̇,İsmail Hakki Akgun,Erdal Bedi̇r

doi:10.21448/ijsm.496724

Abstract

Stevia rebaudiana Bertoni, which is an important plant for the food and health sector, contains calorie-free natural sweet-tasting steviol glycosides (SGs). In the present study, the effects of different elicitors [methyl jasmonate (MeJA), salicylic acid (SA), or chitosan (CHI)] on the in vitro production of stevioside and rebaudioside A were carried out. For this purpose, 3-week-old in vitro plantlets were transferred into 250 mL flasks containing liquid woody plant medium (WPM) supplemented with MeJA, SA, or CHI at different concentrations (0, 50, 100, or 200 µM), and were exposed to these elicitors for 2 weeks. A HPLC method was developed to quantify the aforementioned SGs in the cultivated plantlets and all of the elicitor types and concentrations resulted in an increase in stevioside production ranged between 2.87 mg/g dry weight (DW) (Control) and 50.07 mg/g DW (100 µM MeJA). The highest number of shoot, node, leaf, leaf length, and biomass accumulation and shoot length were observed with application of 100 µM CHI and control, respectively. The present findings open new perspectives for increasing the stevioside production using a plant tissue culture system.

Highlights

Stevia rebaudiana (Bertoni), native to the eastern Paraguayan rainforests, is a member of the family Asteraceae
We found that because of long exposure time, salicylic acid (SA) and MeJA effected the shoot growth negatively; with the concentrations of 50 μM MeJA and 100 μM SA, we obtained approximately an 8-fold increase in the stevioside content when compared to the control
In vitro clonally propagated plantlets obtained from single seed descent seedlings of S. rebaudiana in the Bioengineering Department of Ege University were used as the plant material

Summary

Introduction

Stevia rebaudiana (Bertoni), native to the eastern Paraguayan rainforests, is a member of the family Asteraceae. The 2 major SGs are stevioside and rebaudioside A, while other lower-concentration SGs include steviolbioside, rebaudioside B, C, D, E, F, and dulcoside A [5, 6]. These SGs, due to their intense sweetness, have become an attractive sugar alternative in the food industry [7] as well as in the health sector. Due to these benefits, increasing the production of SGs and understanding their mechanism are of great interest

Objectives

Methods

Results