Epicuticular wax variability of Juniperus deltoides R.P. Adams from the central Balkan – Ecology and chemophenetics

Phytochemistry and Micromorphology of Epicuticular Waxes in Four Juniper Species With Fragmented Distribution in the Balkans

The cuticle is important in the interaction between the plant and its environment, especially in the dry areas. Four species of junipers from the section Sabina wild growing in the Balkans were selected to study leaf wax composition using GC/MS and GC-FID and its surface morphology under SEM to understand the correlation between the distribution and/or habitat of these species and their cuticles. SEM micrographs showed continuous, smooth epicuticular layers with crusts in all species but with a species-specific distribution of different 3D crystalloid types and different cuticle thickness. n-C33 alkane was the most abundant compound, followed by n-C29, n-C31, and n-C35, depending on the species and the site. The average chain length (N) was the lowest in J. phoenicea, but with the greatest dispersion around it. At the same time, the two most continental species (J. foetidissima and J. excelsa) show the N with the lowest dispersion around it. The statistical analyses confirmed the significance of climate on the evolution of the specific epicuticular wax composition in studied junipers.

Clinopodium L. Taxa from the Balkans-Are There Unique Leaf Micromorphological and Phytochemical Patterns?

The concept of the genus Clinopodium L. has changed considerably since its first description. Most of the currently accepted species of the genus have traditionally been treated as separate genera in the group Satureja sensu lato: Clinopodium L., Calamintha sensu Miller or Moench, and Acinos sensu Miller or Moench. This study aimed to gain a better insight into the species diversity of Clinopodium L. from the Balkans by analyzing the taxa that have traditionally been placed in separate genera. The alkane profile and the micromorphological characteristics of the leaves are analyzed. The leaves are visualized using scanning electron microscopy, and alkanes are isolated using n-hexane as a solvent and analyzed using gas chromatography/mass spectrometry. The alkane profile showed the differentiation of the Acinos-group from the other taxa based on the dominant n-C31, while most of the other taxa contained n-C33 as the dominant alkane. The micromorphological features also showed clear differences between the previously recognized genera, especially in the capitate trichomes. The results showed that micromorphological patterns are highly variable in certain groups of the genus Clinopodium.

Morphological and phylogenetic features of the Crimean population of Juniperus deltoides R.P. Adams

Juniperus deltoides is a relict species from the Tertiary Period. It is a typical representative of the Mediterranean group of the section Juniperus. It is included in the Red Books of the Republic of Crimea and the city of Sevastopol. Until recently, it was believed that a population of J. oxycedrus grew in Crimea. Currently, J. deltoides is described as a cryptic species, morphologically difficult to distinguish from J. oxycedrus. As a result, it became necessary to conduct a series of detailed studies to determine the morphological and phylogenetic features of the Crimean cryptic population in order to identify it as being one of the species of the cryptic pair. The studies were carried out in two stages: at the first stage, the morphological features of the vegetative and generative organs and their difference from J. oxycedrus were determined; the second stage included genetic research. The length of the needles of the Crimean population is 12.94 ± 0.19 mm, which corresponds to the Eastern Italian population of J. deltoides. At the same time, the width of the needles is 1.39 ± 0.02 mm, which is typical of the Portuguese population of J. oxycedrus. The dimensions of the cones are d1 (conditional height) = 7.54 ± 0.14 mm, and d2 (conditional width) = 9.11 ± 0.09 mm, which is more in line with J. deltoides. The shapes of the cones are very diverse. Some individuals have cones, the covering scales of which are visually indistinguishable, and their tops are completely fused. A similar phenomenon is characteristic of the Western Mediterranean populations of J. oxycedrus. Morphological analysis of the vegetative and generative organs of J. deltoides showed that when these two traits are combined, it is not possible to reliably distinguish between J. deltoides and J. oxycedrus individuals. Nuclear (ITS internal transcribed spacer) and chloroplast (petN-psbM, trnS-trnG) non-coding regions of the genome were used for genetic analysis. Studies have shown that the nuclear regions of genes have greater variability than chloroplast regions. The sequences obtained in this work formed a clade with J. deltoides samples 9430 and 9431 (BAYLU) growing in Turkey, which makes it possible to assign the samples studied to J. deltoides.

Interactions between Natural Products-A Review

Plant-based natural products have been used as a source for therapeutics since the dawn of civilization. According to the World Health Organization (WHO), more than 80% of the world's population relies on traditional medicine for their primary healthcare. Numerous natural extracts, widely known in Traditional Chinese Medicine, Indian Ayurveda medicine and other practices, have led to the modern discovery and development of new drugs. Plants continuously interact with their environment, producing new compounds and ever-changing combinations of existing ones. Interestingly, some of the compounds have shown lower therapeutic activity in comparison to the extract they were isolated from. These findings suggest that the higher therapeutic activity of the source extract was due to the synergistic effect of several compounds. In other words, the total therapeutic potential of the extract cannot be explained only by the sum of its parts alone. In traditional medicine, most herbal remedies are based on a mixture of plants, and it is the interaction between different constituents that amplifies their therapeutic potential. Considering the significant influence traditional medicine has on human healthcare, knowing and studying the synergistic effect of compounds is paramount in designing smart therapeutic agents.

Leaf surfaces and neolithization - the case of Arundo donax L

Arundo donax L. (Arundinoideae subfamily, Poaceae family) is a sub-tropical and temperate climate reed that grows in arid and semi-arid environmental conditions, from eastern China to the Mediterranean basin, suggesting potential adaptations at the epicuticular level. A thorough physical-chemical examination of the adaxial and abaxial surfaces of A. donax leaf was performed herein in an attempt to track such chemophenetic adaptations. This sort of approach is of the utmost importance for the current debate about the hypothetical invasiveness of this species in the Mediterranean basin versus its natural colonization along the Plio-Pleistocene period. We concluded that the leaf surfaces contain, apart from stomata, prickles, and long, thin trichomes, and silicon-rich tetralobate phytolits. Chemically, the dominating elements in the leaf ashes are oxygen and potassium; minor amounts of calcium, silicon, magnesium, phosphorous, sulphur, and chlorine were also detected. In both surfaces the epicuticular waxes (whose density is higher in the adaxial surface than in the abaxial surface) form randomly orientated platelets, with irregular shape and variable size, and aggregated rodlets with variable diameter around the stomata. In the case of green mature leaves, the dominating organic compounds of the epicuticular waxes of both surfaces are triterpenoids. Both surfaces feature identical hydrophobic behaviour, and exhibit the same total transmittance, total reflectance, and absorption of incident light. The above findings suggest easy growth of the plant, remarkable epidermic robustness of the leaf, and control of water loss. These chemophenetic characteristics and human influence support a neolithization process of this species along the Mediterranean basin.