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

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.