9 research outputs found
Influence of storage and pre-sowing treatment of southern sweet-grass seeds on their germination and initial growth of seedlings
Introduction: Southern sweet-grass (Hierochloë australis /Schrad./ Roem. et Schult., Poaceae) is a perennial tuft-grass occurring in North-Eastern part of Europe. Its leaves are collected from wild growing plants as an aromatic raw material used in alcohol industry. Due to overharvest, attempts to introduce the plant into cultivation have been undertaken
In vitro propagation of bastard balm (Melittis melissophyllum L.)
An efficient method for in vitro propagation of bastard balm by enhanced axillary shoot branching has been developed. The material to establish in vitro culture was shoot tips collected from three-year-old plants in May. The shoots obtained from initial explants were placed on MS/B5 medium containing 0.1, 0.5 or 1.0 mg/l BA with 0.01 mg/l NAA or without the auxin. The highest number of shoots per explant was obtained on the medium with 1.0 mg/l BA (3.9 shoots per explant). For the rooting of shoots ½ MS/B5 with IBA (0.25, 0.50 and 1.0 mg/l) medium was used. The medium without plant growth regulators served as a control. The best root regeneration was observed on the medium without IBA (87.1% of cuttings rooted). IBA used in the medium for shoot rooting affected the morphological traits of obtained microcuttings but not affected their weight. Irrespective of auxin concentration in this medium, obtained microcuttings acclimated in ex vitro conditions very well
Spectroscopic Studies on the Molecular Ageing of Serum Albumin
Pathological states in the organism, e.g., renal or hepatic diseases, cataract, dysfunction of coronary artery, diabetes mellitus, and also intensive workout, induce the structural modification of proteins called molecular ageing or N-A isomerization. The aim of this study was to analyze the structural changes of serum albumin caused by alkaline ageing using absorption, spectrofluorescence, and circular dichroism spectroscopy. The N-A isomerization generates significant changes in bovine (BSA) and human (HSA) serum albumin subdomains—the greatest changes were observed close to the tryptophanyl (Trp) and tyrosyl (Tyr) residue regions while a smaller change was observed in phenyloalanine (Phe) environment. Moreover, the changes in the polarity of the Trp neighborhood as well as the impact of the ageing process on α-helix, β-sheet content, and albumin molecule rotation degree have been analyzed. Based on the spectrofluorescence study, the alterations in metoprolol binding affinity to the specific sites that increase the toxicity of the drug were investigated
Energy Efficiency of LEDs during Micropropagation of Helleborus ‘Molly’s White’
For many years, there has been a growing trend toward producing plants using tissue culture, the most efficient method at present. Every year, more and more protocols for micropropagation of economically valuable species are appearing. Many factors influence the regenerating explants under sterile laboratory conditions. One of the most important is light. The aim of the present study was to increase the efficiency of micropropagation of hellebore ‘Molly’s White’ using energy-efficient light-emitting diodes (LEDs), which were compared to traditionally used fluorescent lamps (FLs). To choose the best light and reduce production costs, white, blue or red LEDs with two levels of photosynthetic photon flux density (PPFD), 40 and 70 μmol/m2/s, were used at the multiplication and rooting stages. LED light color has been shown to affect regeneration rate and plant growth in length during micropropagation, while both light parameters (color as well as intensity) affect the length of regenerating shoots and the content of assimilation pigments in plants. The use of white LED light, which gives the highest multiplication rate, at an intensity of 70 μmol/m2/s saves more than 57 kWh during an 8-week micropropagation cycle compared to conventional fluorescent lamps with the same parameters
Morphological and Chemical Traits as Quality Determinants of Common Thyme (Thymus vulgaris L.), on the Example of ‘Standard Winter’ Cultivar
Common thyme is regarded as one of the most important culinary plants. The purpose of the work was to determine the intraspecific variability of common thyme with respect to morphological and chemical characters including the content and composition of essential oil and phenolic compounds in the herb. The objects of the study were 12 clones, vegetatively multiplied from randomly selected individual plants of cultivar ‘Standard Winter’. The morphological observations and harvest of raw materials were carried out in the first year plants’ vegetation. The highest differences between clones were on fresh and dry weight of herb (CV = 0.38 and 0.36, respectively), width of leaves (CV = 0.21), and density of glandular trichomes on the abaxial surface of leaves (CV = 0.29). Examined clones were also differentiated as to the chemical features. Essential oil content (performed by hydrodestillation) and composition (by GC-MS and GC-FID) were determined and they ranged from 2.10 to 4.38 g × 100 g−1 DW. Here, thymol, γ-terpinen, and p-cymen were the dominant compounds. Clone no. 4 was distinctive as to the highest content of essential oil followed by the highest share of thymol (54.59%). The total content of phenolic acids and flavonoids (determined according to PPh 6th) also differed among clones (CV = 0.38 and 0.36, respectively). Using a validated HPLC-DAD method, the following compounds were identified: caffeic, rosmarinic, p-coumaric acids, luteolin 7-O-glucoside, naryngenin, and (−)-epicatechin. Here, rosmarinic acid followed by luteolin 7-O-glucoside were present in the highest amounts (611.47–2675.59 and 46.77–325.11 mg × 100 g−1 DW, respectively). The highest differences between clones were the contents of p-coumaric acid (CV = 0.59), luteolin 7-O-glucoside (CV = 0.50) and rosmarinic acid (CV = 0.40). Such a high range of variability can provide problems with raw material standardization. Nevertheless, it opens possibilities for breeders, whereas individual plants/clones may become valuable components for breeding
Diffuse leptomeningeal glioneuronal tumor in a 4.5-year-old girl : a case report and review of the literature
Synthesis and biological activity of Nα-[4-[N-[(3,4-dihydro-2-methyl-4-oxo-6-quinazolinyl)methyl]-N-propargylamino]phenyl-acetyl]-L-glutamic acid.
2-Deamino-2-methyl-N10-propargyl-5,8-dideazafolic acid (ICI 198583) is a potent inhibitor of thymidylate synthase. Its analogue, Nα-[4-[N-[(3,4-dihydro-2-methyl-4-oxo-6-quinazolinyl)methyl]-N-propargylamino]phenylacetyl]-L-glutamic acid, containing p-aminophenylacetic acid residue substituting p-aminobenzoic acid residue, was synthesized. The new analogue exhibited a moderately potent thymidylate synthase inhibition, of linear mixed type vs. the cofactor, N5,10 -methylenetetrahydrofolate. The Ki value of 0.34 μM, determined with a purified recombinant rat hepatoma enzyme, was about 30-fold higher than that reported for inhibition of thymidylate synthase from mouse leukemia L1210 cells by ICI 198583 (Hughes et al., 1990, J. Med. Chem. 33, 3060). Growth of mouse leukemia L5178Y cells was inhibited by the analogue (IC50 = 1.26 μM) 180-fold weaker than by ICI 198583 (IC50 = 6.9 μM)