Accumulation of anthraquinones in Morinda citrifolia cell suspensions

Abstract

Cell suspensions of Morinda citrifolia were cultivated in a B5-medium containing 4% sucrose as the sole carbon source and 1 mg 1-1 naphthyl acetic acid (NAA) or 1 mg 1-1 2,4-dichloro-phenoxyacetic acid (2,4-D). Both auxins were able to support growth but only in the presence of NAA anthraquinone production was observed. 2,4-D inhibited the production in NAA cultures. Anthraquinone synthesis took place in the growth and the stationary phase and amounts of 0.2--43.4 mmol (about 100-200 mg) g-1 dry weight could be reached.Under both growth conditions sucrose was hydrolyzed extracellularly by invertase. From the resulting monosaccharides, glucose was taken up preferentially and an appreciable uptake of fructose only took place when medium glucose was exhausted. Sugar uptake rates were similar when cells were grown in NAA and in 2,4-D medium but the intracellular sugar contents (expressed on a dry weight basis) differed considerably. The presence of sucrose, glucose and fructose was demonstrated under both growth conditions. The amounts of sucrose and glucose were much lower in the 2,4-D cells than in the NAA-cells especially during the growth phase. Fructose contents were low and comparable, while in NAA cells an unknown sugar (possibly the sugar moiety of the glycosylated anthraquinones) was observed especially at the end of the growth phase and in the stationary phase. The differences in sugar concentrations were even larger due to the lower water contents of the NAA cells.Respiration of 2,4-D cells was much higher than that of NAA cells during the growth phase. A sharp increase in sugar contents (mainly sucrose) occurred in the 2,4-D cells at the end of the growth phase and corresponded with the fall in respiratory activity.A possible correlation between the lack of production of anthraquinones in 2,4-D cells and a less efficient growth metabolism in these cells is discussed.Abbreviations: AQ -anthraquinones, 2,4-D -2,4-dichloro-phenoxy-acetic acid, DW -dry weight, FW -fresh weight, NAA -, naphthyl acetic acid, pCPO -p-chloro-phenoxy-acetic acid

Anthraquinones from in vitro root culture of Morinda royoc L.

“…2c and 3c). One possible explanation is that replenishment of the medium in each subculture maintains the concentrations of ammonium at high level, which can inhibit the growth of the roots (George 1993). All these findings are in agreement with the results reported by Bulgakov et al (2002) which showed that total AQ production (mg l -1 of the medium) in Rubia cordifolia transgenic cultures was higher when a decrease of fresh biomass accumulation of the transgenic cultures was obtained.…”

Alkaloid production in Vernonia cinerea: Callus, cell suspension and root cultures

“…Similar results were reported by DeEknamkul and Ellis [21] where maximum rate of synthesis of rosamirinic acid in Salvia officinalis cell cultures occurred on addition of NAA. It is always desirable to use morphologically undifferentiated cells for the production of useful metabolites compared to intact plants [22]. In the present study, alkaloid contents in callus and suspension culture was higher than in the aerial parts of the plant.…”