Specificity of Growth and Synthesis of Secondary Metabolites in Cultures in vitro Digitalis lanata Ehrh.

Abstract

Rhizogenic, callus, and suspension cultures in vitro were obtained for Digitalis lanata and their growth, cytophysiological and biochemical characteristics were investigated. The obtained cultures were characterized by good growth characteristics (growth indexes I in the range of 5–13). Suspension cell culture had a specific growth rate μ within 0.2–0.3 days–1 and it was characterized by a two-phase growth curve (growth retardation during the exponential phase). In the obtained cultures, a study of the qualitative and quantitative composition of secondary metabolites by UPLC-ESI-MS and HPLC-ESI-MS showed the absence of cardiac glycosides. At the same time, phenylethanoids and steroidal glycosides of the furostanol type were found in all studied cultures. The total content of phenylethanoids in callus and suspension cultures was approximately 0.5% of the dry biomass. Based on the results of mass spectrometry, ten phenylethanoid structures, including digiciliside A, digiciliside B, maxoside, purpureaside E, and their methyl derivatives and isomers, and also seven furostanol glycosides with aglycones tigogenin and gitogenin were identified. It has been shown that the composition of secondary metabolites depends on the degree of cell differentiation: furostanol glycosides were prevalent in a rhizogenic culture consisting mainly of differentiated cells, while the diversity of phenylethanoids significantly increases in callus and suspension cell cultures consisting of dedifferentiated cells. The results of the study confirm the hypothesis put forward in our previous works about the specificity of secondary metabolism and its high intensity in plant cell cultures.

The Hypoglycemic and Hypocholesterolemic Activity of Dioscorea deltoidea, Tribulus terrestris and Panax japonicus Cell Culture Biomass in Rats with High-Fat Diet-Induced Obesity

“…However, the phytochemical composition of such biomass may be altered compared to their respective donor plants. This, for example, was the case in the Digitalis lanata cell culture which contained a complex mixture of phenylethanoid compounds, including digiciliside A, digiciliside B, maxoside, purpureaside E, and their methyl derivatives and isomers, as well as seven furostanol glycosides with aglycones tigogenin and gitogenin but not cardiac glycosides that are major bioactive metabolites of the plants [ 68 ]. Phytoecdysteroid composition in the cell cultures of Ajuga turkestanica was narrowed compared to hairy roots or whole plants while a number of phenylpropanoids were detected in callus cultures [ 69 , 70 ].…”

Selection of a Digitalis purpurea Cell Line with Improved Bioconversion Capacity of Hydroquinone into Arbutin

“…A better growth is justified at certain inoculum densities depending on plant species, culture conditions, as well as on the specific surface area of the cells and the dispersed nature of cell suspensions, which can make them more prone to leakage of key growth factors/cellular contents to medium [37]. However, similar inoculum/culture medium ratios (10-12.5% v/v) were reported as optimum in the related Digitalis lanata species [43,44].…”