Tussilago farfara L. is a traditional medicinal plant valued for its potentially health-promoting metabolites. Its herbal raw material has been recognized and used since ancient times and continues to be widely used in traditional medicine. Introducing this plant species to in vitro cultivation is a challenging task, but once the protocol is developed, such cultures can provide an abundant and inexhaustible source of plant material. In this study, we report the successful induction and growth of vigorous T. farfara callus in vitro. Callus induction was achieved on MS solid media with the combination of indole-3-acetic acid (3 mg/L) and benzyl aminopurine (2 mg/L) in darkness, whereas it appeared inefficient under light conditions and in suspension culture. We present a detailed description of callus growth kinetics, morphological analysis, photosynthetic activity, and biochemical parameters (including protein content and photosynthetic pigments) supported by histological studies. Furthermore, we observed the potential for organogenesis and somatic embryogenesis. This method for the in vitro propagation of T. farfara, along with callus culture maintenance, offers a wide range of applications in pharmacy for the production of valuable metabolites. Moreover, it could benefit the environment by reducing the depletion of natural populations of this species and may serve as an alternative strategy for species conservation in light of global warming.

Gene encoding mercuric ion reductase, merA is a crucial component of the mer operon for reduction of nonorganic mercury ions into less toxic form. The merA gene or its fragments are commonly used as a molecular marker of bacterial resistance to mercury. In this study, it was tested whether the merA gene can be considered as a molecular marker of mercury bacterial resistance. For this purpose, the presence of the mer operon in bacteria isolated from the microbiota of Tussilago farfara L. growing in post-industrial mercury-contaminated and non-contaminated areas was verified by merA gene identification. Mercury resistance was determined by analyzing the bacterial growth parameters in standard Luria-Bertani (LB) medium with mercury concentration of 0.01% (w/v) and in medium without mercury addition. The results obtained showed that the merA gene was present in all T. farfara L. bacterial isolates growing in both mercury-contaminated and noncontaminated soils, however, only the isolates from mercury-contaminated areas were able to grow under mercury conditions. Although merA is commonly regarded as a molecular marker of bacterial mercury resistance, results of our research indicate the need for a verification of that statement/thesis and further investigation of bacterial mercury resistance to indicate other its key markers, structures, or mechanisms.

The purpose of this research was to obtain recombinant violaxanthin de-epoxidases (VDEs) from two species. The first one was VDE of Arabidopsis thaliana (L.) Heynh. (WT Columbia strain) (AtVDE) which in vivo catalyzes conversion of violaxanthin (Vx) to zeaxanthin (Zx) via anteraxanthin (Ax). The second one was VDE of Phaeodactylum tricornutum Bohlin, 1897 (CCAP 1055/1 strain) (PtVDE) which is responsible for de-epoxidation of diadinoxanthin (Ddx) to diatoxanthin (Dtx). As the first step of our experiments, open reading frames coding for studied enzymes were amplified and subsequently cloned into pET-15b plasmid. For recombinant proteins production Escherichia coli Origami b strain was used. The molecular weight of the produced enzymes were estimated approximately at 45kDa and 50kDa for AtVDE and PtVDE, respectively. Both enzymes, purified under native conditions by immobilized metal affinity chromatography, displayed comparable activity in assay mixture and converted up to 90% Vx in 10 min in two steps enzymatic de-epoxidation, irrespective of enzyme origin. No statistically significant differences were observed when kinetics of the reactions catalyzed by these enzymes were compared. Putative role of selected amino-acid residues of AtVDE and PtVDE was also considered. The significance of the first time obtained recombinant PtVDE as a useful tool in various comparative investigations of de-epoxidation reactions in main types of xanthophyll cycles existing in nature are also indicated.

Tussilago farfara L. is a traditional medicinal plant valued for its potentially health-promoting metabolites. Its herbal raw material has been recognized and used since ancient times and continues to be widely used in traditional medicine. Introducing these plants to in vitro cultivation is a challenging task, but once the protocol is developed, such cultures can provide an abundant and inexhaustible source of plant material. In this study, we report the successful induction and growth of vigorous T. farfara L. callus in vitro. Callus induction was achieved on solid media in darkness, whereas it appeared inefficient under light conditions and in suspension culture. We present a detailed description of callus growth kinetics, morphological analysis, photosynthetic activity and biochemical parameters (including protein content and photosynthetic pigments) supported by histological studies. Furthermore, we observed potential for organogenesis and somatic embryogenesis. This method for in vitro propagation of T. farfara, along with callus culture maintenance, offers a wide range of applications in pharmacy and could benefit the environment by minimizing the depletion of natural populations of this species.

Medicinal plants remain one of the most important sources of therapeutically relevant compounds for pharmaceutical, nutraceutical, and biotechnological applications. However, the naturally low abundance of many specialized metabolites, considerable phytochemical variability, and increasing environmental pressures continue to limit the sustainable exploitation of plant-derived bioactive compounds. This review summarizes current strategies aimed at identifying, understanding, and enhancing the production of medicinally valuable metabolites while highlighting both biological limitations and emerging technological opportunities. Particular attention is given to the interplay between primary and secondary metabolism and its role in determining biosynthetic efficiency in both natural and engineered systems. Beyond discussing established methodologies, this review adopts a broader perspective by incorporating less frequently addressed aspects, including the influence of climate change on metabolite production, the application of bioinformatics-supported approaches to improve bioprospecting efficiency, and the growing role of nanoparticles as elicitors in plant biotechnology. These topics are considered alongside advances in tissue culture technologies, metabolic engineering, molecular approaches, and systems-level analyses aimed at improving metabolite yield and production stability. Current evidence suggests that no single technological framework is sufficient to address the complexity of medicinal plant metabolism. Hence, rather than presenting individual technologies as isolated solutions to specific biosynthetic bottlenecks, this review emphasizes that medicinal plant metabolism should be considered a highly interconnected system in which environmental, molecular, and physiological factors collectively determine production outcomes.