Improved production of dibenzocyclooctadiene lignans in the elicited microshoot cultures of Schisandra chinensis (Chinese magnolia vine)

Abstract

Dibenzocyclooctadiene lignans are a specific group of secondary metabolites that occur solely in Schisandra chinensis. The aim of the presented work was to boost the accumulation of lignans in the agitated microshoot cultures of S. chinensis, using different elicitation schemes. The experiments included testing of various concentrations and supplementation times of cadmium chloride (CdCl₂), chitosan (Ch), yeast extract (YeE), methyl jasmonate (MeJa), and permeabilizing agent-dimethylsulfoxide (DMSO). After 30 days, the microshoots were harvested and evaluated for growth parameters and lignan content by LC-DAD method. The analyses showed enhanced production of lignans in the elicited S. chinensis microshoots, whereas the respective media samples contained only trace amounts of the examined compounds (< 5 mg/l). Elicitation with CdCl₂ caused up to 2-fold increase in the total lignan content (max. ca. 730 mg/100 g DW after the addition of 1000 μM CdCl₂ on the tenth day). Experiments with chitosan resulted in up to 1.35-fold increase in lignan concentration (max. ca. 500 mg/100 g DW) after the supplementation with 50 mg/l on the first day and 200 mg/l on the tenth day. High improvement of lignan production was also recorded after YeE elicitation. After the elicitation with 5000 mg/l of YeE on the first day of the growth period, and with 1000 and 3000 mg/l on the 20th day, the lignan production increased to the same degree-about 1.8-fold. The supplementation with 1000 mg/l YeE on the 20th day of the growth cycle was chosen as the optimal elicitation scheme, for the microshoot cultures maintained in Plantform temporary immersion system-the total content of the estimated lignans was equal to 831.6 mg/100 g DW.

Keywords: Abiotic elicitors; Biotic elicitors; Elicitation; In vitro cultures; Schisandra lignan production; Temporary-immersion bioreactor.

Fig. 1

The effect of cadmium chloride on biomass growth in agitated shoot cultures of S. chinensis. a Fresh weight (FW). b Dry weight (DW). c Growth index (Gi). Symbols used: C—control group without cadmium chloride treatment. The cultures were grown for 30 days

Fig. 2

The effect of yeast extract on biomass growth in agitated shoot cultures of S. chinensis. a Fresh weight (FW). b Dry weight (DW). c Growth index (Gi). Symbols used: C—control group without yeast extract treatment. The cultures were grown for 30 days

Fig. 3

The effect of chitosan on biomass growth in agitated shoot cultures of S. chinensis. a Fresh weight (FW). b Dry weight (DW). c Growth index (Gi). Symbols used: C—control group without chitosan treatment, S—control group without chitosan treatment, supplemented with neutralized hydrochloric acid solution. The cultures were grown for 30 days

Fig. 4

The effect of yeast extract (added at 1000 mg/l on day 20) on biomass growth in agitated and bioreactor-grown shoot cultures of S. chinensis. a Fresh weight (FW). b Dry weight (DW). c Growth index (Gi). The cultures were grown for 30 days

Fig. 5

Comparison of reached maximal total contents [mg/100 g DW ± SD] of dibenzocyclooctadine lignans in agitated and bioreactor microshoot cultures of S. chinensis, obtained after optimization of the elicitation process, with their contents in reference plant material—leaves and fruits of soil-grown plant (Szopa et al. 2016b)