Abstract: The abiotic elicitation is one of the methods for
increasing the secondary metabolites production in plant tissue
cultures and it seems to be more effective than traditional strategies.
This study verified the use of silver nitrate as elicitor to enhance
flavonolignans and flavonoid taxifolin production in suspension
culture of Sylibum marianum (L.) Gaertn. Silver nitrate in various
concentrations (5.887.10-3 mol/L, 5.887.10-4 mol/L, 5.887.10-5
mol/L) was used as elicitor. The content of secondary metabolites in
cell suspension cultures was determined by high performance liquid
chromatography. The samples were taken after 6, 12, 24, 48, 72 and
168 hours of treatment. The highest content of taxifolin production
(2.2 mg.g-1) in cell suspension culture of Silybum marianum (L.)
Gaertn. was detected after silver nitrate (5.887.10-4 mol/L) treatment
and 72 h application. Flavonolignans such as silybinA, silybin B,
silydianin, silychristin, isosilybin A, isosilybin B were not produced
by cell suspension culture of S. marianum after elicitor treatment.
Our results show that the secondarymetabolites could be released
from S. marianum cells into the nutrient medium by changed
permeability of cell wall.
Abstract: Lawsone is a pigment that occurs naturally in plants.
It has been used as a skin and hair dye for a long time. Moreover, its
different biological activities have been reported. The present study
focused on the effect of lawsone on a plant cell model represented by
tobacco BY-2 cell suspension culture, which is used as a model
comparable with the HeLa cells. It has been shown that lawsone
inhibits the cell growth in the concentration-dependent manner. In
addition, changes in DNA methylation level have been determined.
We observed decreasing level of DNA methylation in the presence of
increasing concentrations of lawsone. These results were
accompanied with overproduction of reactive oxygen species (ROS).
Since epigenetic modifications can be caused by different stress
factors, there could be a connection between the changes in the level
of DNA methylation and ROS production caused by lawsone.