Search

24 p.-7 fig., Epigenetic modifications play a vital role in the preservation of genome integrity and in the regulation of gene expression. DNA methylation, one of the key mechanisms of epigenetic control, impacts growth, development, stress response and adaptability of all organisms, including plants. The detection of DNA methylation marks is crucial for understanding the mechanisms underlying these processes and for developing strategies to improve productivity and stress resistance of crop plants. There are different methods for detecting plant DNA methylation, such as bisulfite sequencing, methylation-sensitive amplified polymorphism, genome-wide DNA methylation analysis, methylated DNA immunoprecipitation sequencing, reduced representation bisulfite sequencing, MS and immuno-based techniques. These profiling approaches vary in many aspects, including DNA input, resolution, genomic region coverage, and bioinformatics analysis. Selecting an appropriate methylation screening approach requires an understanding of all these techniques. This review provides an overview of DNA methylation profiling methods in crop plants, along with comparisons of the efficacy of these techniques between model and crop plants. The strengths and limitations of each methodological approach are outlined, and the importance of considering both technical and biological factors are highlighted. Additionally, methods for modulating DNA methylation in model and crop species are presented. Overall, this review will assist scientists in making informed decisions when selecting an appropriate DNA methylation profiling method., This publication is supported by COST (European Cooperation in Science and Technology) through grant CA19125 awarded to the COST Action 'Epigenetic mechanisms of crop adaptation to climate change' (EPI-CATCH), grant number CA19125 (https://www.epicatch.eu)".

The plant kingdom produces an overwhelming number of structurally diverse specialised metabolites. One of the less studied groups of specialised metabolites are flavonoid dimers known as biflavonoids, which consist of two identical or non-identical flavonoid units. They exhibit higher bioactivity than their monomeric subunits and are considered potential drugs in the pharmaceutical industry and potential antioxidants and antimicrobials in the food industry. However, it remains unclear why some plant species produce dimeric structures of flavonoids, under what conditions, and what role biflavonoids play in plant growth and development. In our project, we address such limitations by studying biflavonoids in Ginkgo biloba L., a so-called "living fossil" and a plant widely used in traditional medicine. It is one of the most characteristic plants. It possesses a number of fascinating characteristics, including a large genome, outstanding resistance/tolerance to abiotic and biotic stresses, and dioecious reproduction, making it an ideal model species for biological studies. Its great tolerance to adverse environmental conditions is demonstrated by the fact that Ginko trees growing within 1-2 kilometres of Hiroshima since the atomic bomb explosion in 1945 were among the few living things in the area that survived the blast and were soon healthy again. This poster will provide an overview of the structure and biological activity of biflavonoids and explain why G. biloba is an ideal model for studying biflavonoids. We will also present the preliminary results of the recently launched project "Biflavonoids role in plants: Ginkgo biloba L. as a model system", funded by the Croatian Science Foundation (HRZZ- UIP-2019-04-1018).

Flavonoids exist as aglycones, glycosides, or dimeric forms called biflavonoids. Biflavonoids presence is commonly reported in plants used in traditional and modern medicine, indicating their potential health benefits. Biflavonoids are not present in all plant species, but are found only in some species. One of them is ginkgo (Ginkgo biloba L.), a well-known medicinal plant used in traditional and Western medicine. Unfortunately, most phytochemical studies published on ginkgo in recent years have neglected biflavonoids as important bioactive components that have come into scientific focus as important health-promoting compounds. So, the aim of this work was to conduct a comprehensive literature review on the presence of biflavonoids in ginkgo and to summarize data on the chemistry, diversity, and biological factors affecting their presence in ginkgo, as well as their bioactive and health-related properties. To date, the presence of 13 biflavonoids in ginkgo has been demonstrated, of which amentoflavone, bilobetin, sciadopitysin, ginkgetin, and isoginkgetin are the most common. Their role in plants remains unknown, but their bioactivity and potential role in treating human health are better understood and are associated with antioxidant, anticancer, antiviral, antibacterial, antifungal, and anti-inflammatory activities, as well as their potential role in treating cardiovascular, metabolic, and neurodegenerative diseases.

The ginkgo (Ginkgo biloba L.) is the only living dioecious species in the Ginkgoaceae family. It is characterized by a large genome and high stress tolerance, including abiotic and biotic stresses and dioecious reproduction. Ginkgo trees, often more than 200 years old, are found as ornamental plants in many European cities. The leaves and fruits have been used in medicine for several centuries and the best known beneficial effect is on cognitive ailments. Its good stress tolerance and medicinal use may be related to the presence of various phytochemicals, as biosynthesis and diversity of specific metabolites are crucial for survival in a stressful environment. The biologically active compounds in ginkgo are from the group of flavonoids, terpenoids, alkylphenols and alkylphenolic acids, carboxylic acids, lignans, proanthocyanidins, polyprenols, and polysaccharides. To date, more than one hundred flavonoids with unique structures have been identified. In a GinkoBiFlav project (HRZZ-UIP -2019-04-1018), we focus on biflavonoids in ginkgo. Biflavonoids are flavonoid dimers consisting of two identical or non-identical flavonoid units linked in a symmetrical or asymmetrical manner. Although they have biological activity, their role in plants is unknown. Recently, we have summarized literature data on the diversity, presence, and biological activity of biflavonoids in ginkgo, which we will present. We will also discuss other research directions that could elucidate the role of biflavonoids in ginkgo, possibly related to adaptation to a changing environment.

Medicinal plants are highly valued for their bioactive compounds and acquisition of these compounds often includes an unregulated exploitation of natural populations. In vitro culture offers conditions to grow plants that are independent of season, geography, climate and can contribute to establishment of uniform or even novel medicinal compounds. Additionally, in vitro culture offers methods for enhancement of secondary metabolite production (elicitation). Elicitation is considered as one of the most cost- effective technique for improvement of metabolite production through application of elicitors. Elicitors include abiotic and biotic compounds that include inorganic salts, phytohormones such methyl jasmonate, Salicylic acid, brassinosteroids, bacterial extracts, yeast extracts and fungal elicitors. The continuous improvement of transcriptomics enables use of in vitro culture for engineering and production of target compounds.

The very first report on the phenolic composition of aerial parts of Aconitum lycoctonum L., a species belonging to the toxic Aconitum genus, is presented here. Aerial parts were subjected to the extraction with four different solvents and analyzed via LC-MS/MS for the content of phenolic acids and flavonoids. Furthermore, isolated extracts were tested for antimicrobial and antioxidant activities. Ethanolic extracts of both flowers and vegetative parts (leaves and stems) were found to be the richest in the phenolic compounds, following the water extracts. Ethanolic extract of flowers was very rich in flavonoid apigenin, while high levels of salicylic and 4-hydroxybenzoic acids were found in the same extract of leaves and stems. On contrary, water extract contained significant amounts of kaempferol and rosmarinic acid. All extracts showed potent antioxidant activity, which is correlated with the content of phenolics. The antimicrobial assay showed that all extracts, except aqueous, were quite potent against all microbial organisms tested.